text:
Baker, James Letter: 1940 April 5th
Date: April 5th 1940
I have been to Brighton and had a wonderful time. Down there they have an ice rink which is in operation continuously throughout the year. They have a league of six teams, two of which played on the Sunday I was there. Of course I went to see them and enjoyed watching the game although it seemed very slow and tame in comparison to the game which we play because they are not allowed to body check. When the Army teams play (there are six of them and the Pats have one of the best) the crowds get some real excitement. There have been more minutes of fights on the ice than there have been minutes of hockey played. At one fight in London which lasted thirty-five minutes, nineteen players were all on the ice at one time. Even the officers in charge of each team and finally the crowd joined in and had a grand melee. A special squad of policemen had to be called in to stop the fight which threatened to develop into a riot. So you see we have transplanted our national sport over here with a vengeance. The game at Brighton between the Pats and Medicos was a very good one and also a very funny one. About two hundred officers and doctors from the RAMC and the RCAMC were there as well as a few of our officers. About the middle of the second period, one of our men got cut rather badly over the eye by a flying stick.. He was down on the ice bleeding pretty freely and all the players grouped around him offering help and or sympathy or whatever they do when someone is hurt. The crowd was hushed, tensely waiting and cramming forward in their seats to see what had happened when suddenly - in that deathly stillness, one of our officers yelled at the top of his voice: "Is there a doctor in the house?"
And you should have heard the roar which nearly raised the roof off as the crowd burst out laughing, for as I said before there were only about two hundred doctors present. If Hitler could have heard that laugh, he would know just how "downhearted and glum" the British people are.
Brighton is a beautiful place. I will always remember my first view of it in daylight. I had arrived in the blackout and of course had no idea what the town was like. When I awoke the next morning what a sight met my eager gaze! The beautiful golden sunlight was streaming down through a hole in the clouds lighting up the snow-white cliffs to the east and glimmering on the silver sea which lay in idolization at their feet, the grassy black smoke plume from an old British freighter obscured the horizon while near at hand, the smoke from a thousand chimney pots danced lazily upward into the quiet air. Everything was so still and peaceful! War seemed a million miles away instead of only a couple of hundred there across the Channel.
Down below me in the streets the hustle and stir of another day was just beginning. Two women were standing in the doorway of their shops gossiping busily, their voices drifted up to me amidst the clatter of bottles in the milkman's cart bumping along over the cobblestones and the banging a man was making, taking down his store shutters farther along the street.
Later that morning I went for a stroll along the justly "Promenade", a paved walk built in three terraces lined with shops, amusement halls, bathing pools, boating pools, flower gardens, aquariums, bathing machines, (O yes, there are still bathing machines at Brighton) and a thousand and one other amusing, exciting or interesting things. Photographers snapped my picture every few yards and then tried to sell the prints back to me for sixpence a dozen; old women hawked their wares, raising their raucous voices in blood-curdling shrieks far worse than any war whoop a blood-curdling Indian ever raised; sideshow barkers continuously invited the crowds to "stop inside and see Emma - the world's fattest woman" and "Beau Brugnel - the world's ugliest man" or some other equally fascinating creature; tiny cars raced around a wooden platform bumping into each other while shrill screams of laughter came from their happy carefree occupants at each head-on collision; tiny motor boats raced madly over the surface of the boating pool; the crowd in front of the aquarium roared with laughter at the sight of the fishes being fed; the shooting galleries added their measure to this bedlam of noise.
And superimposed over it all was the drone of the Coast Patrol continuously passing and re-passing overhead: for Great Britain is at war and the increasing watch must go on night and day no matter how civilians choose to amuse themselves.
How great was the contrast between this bustle and bedlam and the tranquillity and peacefulness which surrounded me the next day when I visited the Tudor Close - an old Inn which is advertised as "The Most Beautiful Inn in Sussex": and indeed it is worthy of the superlative. It is situated a fifteen minute bus ride from Brighton in the quaint old-fashioned village of Rottindean - right in the midst of the beautiful rolling "Downs" of Southern England. To look at it from the outside one would never dream that it is a fully modernized and comfortable hotel. It was at one time an old cowshed until someone with ideas and the money to carry them out, remodeled it. A long, low, rambling, ivy-covered building in the form of a hollow square with steely sloping gables, tiled roofs and round, square, twisted, oval (indeed every imaginably) shaped chimneys - all smoking merrily. Tiny, leaded windows with diamond-shaped panes and green glass confronted me when I stepped off the bus.
I walked up the magnificent carriage drive which swept up to the huge oaken door with gleaming brass handle and hinges. The door opened before me at the touch of an unseen hand and I walked through the portal into a completely new (or rather old) world, for - although there are carpets inches thick on the floors, central heating and running hot and cold water in every bedroom, the atmosphere of Tudorism has been so effectively maintained in the decorations and furnishings that I almost expected to meet Sir Walter Raleigh and Queen Elizabeth 1 around the next corner of the passage, or see the pages and waiters dressed in vari-colored ruffs and jerkins. But I regret to say they were dressed in conventional white coats and black ties and neither Sir Walter nor Queen Elizabeth were in evidence the day I was there.
The whole atmosphere of the place is a delightful blend of the ancient medieval and the ultra-modern. In every room was some old, strange or beautiful object to get excited about. It was like a treasure hunt. In one room I found an oil painting of a very beautiful lady so life-like it seemed about to walk out of the canvas and mingle with us, in the next an intricately carved fire screen caught my eye and held my attention, in the next, a Royal Charter framed in oak and written in Olde Englishe was the treasure. Following that, a huge four postered bed with heavy silk hangings - drawn to reveal snowy white pillow cases, sheets and a beautiful hand-embroidered silken coverlet. And so on through the whole place. Treasure after treasure until my eyes could not grasp the wonder of all the beautiful things seen.
At last I came to the crowning feature of this wonderful place. A superb old fashioned English rose garden with tame pigeons (so tame that they ate right out of my hand) strutting up and down the shady walks, a huge elm tree casting its benevolent shade in one corner, a magnificent weeping willow in the centre and beds of flowers scattered all about. The daffodils, snowdrops and crocuses were all in bloom at the time of my visit and formed a riotous counterpane of color spread over the green turf. Hideous gargoyles - wonderful examples of hand carving, leered down from the gables, birds sang in the elm tree, the pigeons cooed - their soft voices blending harmoniously with the drowsy hum of the bees busily visiting each lovely flower in turn. It was so beautiful and peaceful, so restful to sit in the shade and contemplate that old building which has stood there for centuries: defying both the power of storm and decay. Again how very far away the hideous turmoil of war seemed that glorious afternoon. Yet I had only to glance down at my khaki uniform to realize that if it hadn't been for it - war, I would never have been here to discover for myself this absolute "treasure".
Well I guess that is all for now. I haven't been to London to stay yet, but I have to go up sometime soon so will try to describe what I see there in my next few letters.
Love to all,


text:
Learning from a System Outage, Our First Hackdays and Engineering Team News
Sep 7, 2016 11 min read Reports
Sunil Sadasivan Team Buffer
Buffer Engineering Report
Last month's report
All Engineering reports
All Buffer reports
Requests for buffer.com
Avg. response for buffer.com
Requests for api.bufferapp.com
Avg. response for api.bufferapp.com
88.1 ms
Bugs & Quality
2 S1 (severity 1) bug reports – 2 closed 100% (In July: 9 S1 Bug reports – 6 closed 66%)
24 S2 (severity 2) reports – 17 Closed 71% (In July: 38 S2 reports – 23 Closed 61%)
Welcome to this month's engineering and innovation report! I'm happy to share we've been making steady progress on key fronts at Buffer. Really excited to share the highlights with you all.
The TL;DR
We're excited to welcome our newest Android Developer! We've also moved a few team members around after closing our Buffercelerator product, Rocket.
After some downtime on Friday, August 19th, we discussed the "5 Whys" to find the root cause and we've instituted several changes because of our findings.
Our data team adjusted our monthly recurring revenue model and it has given us a lot more confidence in our accuracy.
This new model came as a result of two intensive "Hackdays," where the data team focused exclusively on a single project for 48 hours. More results and reflections below!
Team Updates: Teammate moves, new career path framework
We're excited that Joe has accepted our offer to join the team full-time as an Android developer! He's already done some incredible things at Buffer; check his great work on our Android Style guide.
Two other team changes happened this month as well. Rocket, our first Buffercelerator project, has decided to not continue.
This means that Phil has joined us on the main Buffer product again. He'll working with the Growth team to help push out experiments and optimize the value for our users.
Steve, who was also an engineer (previously product designer) in the Growth team, has joined the product engineering team and also help out on engineering tasks for the marketing team.
In August, we were pumped to see Katie move into a new role as an engineering manager. She's already had a huge influence p on the management side. Niel, Katie and Sunil now hold regular weekly syncs to ensure we build a great engineering team and processes.
New Buffer engineering career path framework
One of the key challenges of our current salary formula is the ambiguity of experience levels. It is often tough to decide how and where to place people in these levels. This leads to ambiguity in how engineers can grow in their careers and what this means for their professional development and salary. There's also huge potential that this leads to bias and pay inequity.
It felt like a key time for us to address this challenge head on.
Katie and Niel, getting advice from team members, industry influencers and outside companies, have been working on this for the past month and aim to have this rolled out to the team in September. Excited to share more on this soon.
A "5 Whys" on our system-wide downtime
On August 19, we experienced the largest system-wide outage of the Buffer application in over a year. An engineer merged a pull request that had an unindexed database query in a critical path. This wasn't deployed, which is usual development protocol. Another team member deployed to buffer.com many hours later. We experienced database slowness and customers started seeing Mongo errors on buffer.com.
Reverts solved the problem, though figuring out the root cause took a few hours to pin down. Although the original pull request had gone through a code review, it was not specifically reviewed by someone who could take a look at possible performance implications. The fact that we have many developers working on a system with a single point of failure is a key motivating factor for our efforts to move Buffer to a service oriented architecture.
When we have down time or any serious occurrence at Buffer, we don't point fingers but instead try to look at it as an opportunity to improve. We use a process called the 5 Whys. This allows us to pinpoint process changes to prevent these things from happening again.
Our end conclusion was that there seems to be inconsistent education around working with databases at scale and constructing proper database indexes.
Since this discovery, we've worked to put more visibility on this for the team, as well as make sure that we improve our pull request and code review flows to bring in the right people to review core changes.
A few team members are trying to push our visibility/process even further with apps like Danger. We've also added much more fine-grained monitoring and alerting of database stats using Datadog so that team members will have a clearer picture of what part of the system is failing.
Service oriented architecture update
The push to move Buffer to a more service oriented architecture (SOA) has gone really well this month. We now have around 20 docker containers running in production on Kubernetes 1.3. These services handle 1.49 million requests per week.
We've recently standardized our logging framework for these services, so that when developers build services, they won't have to re-invent the wheel. Steven led the charge here using a sidecar container approach with Fluentd, AWS Kinesis and Elasticsearch. It's currently working at 12k records/hour, this will increase quite a bit over the next few months.
The next challenge on the SOA front will be to figure out how to share and synchronize data across different separate services. We built a proof-of-concept service which uses AWS Kinesis to stream data of Buffer button counts to a separate service. We'll likely explore this more in September and experiment with how we want to scale data and stream processing/PubSub with tools like Apache Kafka and AWS Kinesis.
Improved monitoring and alerting
As Buffer has grown, our systems have become a lot more complex, with many separate databases, servers and services.
We've signed on to Datadog for fully monitoring our infrastructure this month. Before Datadog, we relied on AWS Cloudwatch and New Relic. We were really happy with what Datadog provides, making it much easier to dig in any specific metrics across the entirety of Buffer services. We've set up monitoring on database performance, instance health, service latency, and much more. We also now use ElastAlert to alert on Elasticsearch log events.
We're excited to keep the SOA momentum high going into September. Tigran is busy moving workers that process analytics data from our legacy system to Kubernetes. We're starting with a small percentage, but hope to move fast and be running 50+ of these workers in containers within a couple weeks.
We're also working on a project to break down our widgets infrastructure. We hope to move our video.buffer.com service and eventually Buffer buttons away from dedicated servers and on to the Kubernetes cluster.
Improved 'on-the-hour' posting times
Earlier this month Colin noticed a trend of increased delays for users posting to social networks on the hour. We typically see spikes here as many users prefer to post status updates specifically on the hour, like 8 am sharp.
This triggered us to rework our broadcaster service workers (the logic that posts status updates to services like Facebook/Twitter) to be on dedicated instances instead of shared with other workers.
Here you can see for posts due at 8 am, we'd have ~1,200 posts broadcasted with a delay of 90 seconds or more.
August 3rd 2016:
Our customers expect posts to go out at the time specified, so this was unacceptable. You can also see further delay on posts specified after the hour, like 8:01–8:02am.
After re-working our broadcasters infrastructure here's how things look today:
August 29th 2016:
Now 95% of updates are sent out to services immediately, within the minute specified. We still see about 5% take longer than 60 seconds, so we'll look to improve this further. (This oftentimes can be due to an post that has a large image or video attached.)
Mobile: Speedier iOS; Android style guide
Update by Andy Yates
iOS: Speed update; preparing for 'dark mode'
With iOS 10 around the corner, most of our iOS attention has shifted to getting things ready for all of the new features and UI adjustments that brings.
We also wanted to speed up some of our most-used screens: Buffer and Analytics tables. With so many different elements possible in each cell, it's always been a challenge to keep things scrolling at 60 frames-per-second. We were often seeing slowness and frame drops, especially with more complicated update cells.
Facebook open-sourced a neat little project they use to keep things scrolling smoothly called AsyncDisplayKit. It's been implemented into Pinterest and 4,500+ other apps on the App Store – and now Buffer!
This video shows the current queue that's live in the App Store on the left, with the newly recoded version on the right. You'll notice less skipped frames along with less scroll indicator jumping with iOS calculating the cell heights.
/content/images/wp-content/uploads/2016/09/Async.mp4
Along with these changes we've had the chance to do some future-proofing to allow our updates to display in grids, which will be useful for some upcoming explorations for including Instagram grid views.
We've also spent a bit of time improving how we style the app. Wit rumors about Dark Mode coming to iOS with the introduction of the iPhone 7, we want to make sure we're in a good position to introduce something very quickly. If it doesn't get introduced, we'll join some excellent apps on the store which have introduced dark modes like Tweetbot, Twitter etc.
Android: New coding patterns; upgraded testing
With more hands on Android now, we can start making our whole development process more future proof.
Both our Composer and Queue are ripe for some new ideas and improvements. We are introducing to both a Reactive Coding Style through RxJava, which should helps us simplify the complex logic.
Together with RxJava we are introducing a coding pattern called MVP – Model View Presenter. This will decouple dependencies and help make everything more reliable, solve bugs we currently have and also make it much easier in the future to just jump in and see whats happening in a certain part of the app.
We've also improved the whole process of testing and building our app. Together with our new Android Style guide, we've worked a lot to improve our Jenkins deployment workflow. Jenkins will check every pull request for styling and run a suite of tests. If all is green, Jenkins builds an apk to use for Quality Analysis later on.
We also introduced a Open Source Plugin called "Danger" to our workflows. This helps us keep a great coding culture inside our repos. It warns us in case pull requests get too big, or if a certain pull request has no assignee yet. The rules can basically go as far as you wish.
Example of 2 simples rules:
As a last step, all release builds will run Espresso Tests on different devices through the device farm from Firebase. These are automated tests to click through the app following a script we write for each part and see if all is still functioning.
Data: Hackdays, new MRR model
Update by Michael Erasmus
New MRR model increases confidence
The data analytics team has been focused on providing support to the Product, Happiness and Marketing teams, improving models, data tools and dashboards as well as experimenting with ways to spur creativity and innovation using data.
We've mostly finished up auditing all revenue data for accuracy and building out new MRR movement models. Through auditing, we realized we were missing Stripe Event data, which has caused us to consistently overreport MRR by around 25k.
After switching to a new data pipeline set up by the systems team, we have a lot more confidence in the MRR numbers.
In addition we've built a new MRR movement model that can help us break overall MRR changes down into its components, such as new business, upgrades/downgrades, churn, etc, segmented by plan.
We've already found this to be super helpful. Recently we noticed a slight uptick in MRR and were able to attribute the effects to an experiment on the growth team.
We also brought in new, super accurate revenue forecasts. With this, we can get a good sense of where MRR will be at a certain date in the future within a range of confidence intervals, as well as predict when we will hit a certain amount in MRR.
Marketing data and dashboards, improved GA tracking
We've recently renewed our focus on marketing and data. We've improved some of the dashboards and metrics used by the marketing team, such as metrics around the effect of marketing on trial starts, how our content marketing affected visits and signups, as well as starting work on a greater marketing funnel.
We made some improvements in our Google Analytics tracking in order to make use of funnels and make better data decisions.
Finally, we started some work on measuring and analyzing some of our community work, such as tracking customers whom we've sent swag to.
Innovation and Education: "This Week in Data"
This month, we started a weekly discourse (our version of email) sent to the whole company: This week in data. The idea is to share interesting knowledge and useful learnings from data with the rest of the team.
We also had our first set of Hackdays, in which we blocked off two days to work on anything we wanted and team up however we choose.
We ended up having a ton of fun and completed some amazing mini-projects, some of which have already been valuable for our day-to-day work.
Hackdays were rewarding and fulfilling — there was an awesome energy and camaraderie. We were all amazed by how much we could accomplish in a short period of time.
We would definitely try this again, perhaps even once a quarter. It was cool to see how a hackathon could work in a distributed team (perhaps you'll see this as a blog post soon!)
Data models and tools
We've continued building more powerful and robust tools to scale out our data analysis, as well as better models on of our data. We have completed work to host our internal data analysis framework; dataparrot to run on our Kubernetes cluster, and make it easy to deploy using jenkins.
This means that an analyst can take any ad-hoc data analysis or data modeling job, and run it on as a job, on a scheduled basis as new data flows in.
As you can see, a lot happens nowadays at Buffer in just one month. We're really happy with how August went, and we hope to keep the momentum high going into September.
Is there anything you'd love to learn more about? Anything we could share more of? We'd love to hear from you in the comments!
Check out more reports from August 2016:
People Ops
Shareholder Update: Q2 2020 and July
Buffer in Q2 2018: Our 9th retreat, GDPR compliance, and being named one of Inc's Best Workplaces for 2018
Buffer in Q1 2018: Kicking Off The New Year With Momentum
Buffer in Q4 2017: Profit Sharing, Reflecting on 2017, and Ending the Year With Rest

redpajama_set_name: RedPajamaCommonCrawl


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Encore Boston Harbor warns of furloughs as statewide recreation curfew begins
Updated: 10:25 AM EST Nov 6, 2020
WCVB
Encore Boston Harbor in Everett
SOURCE: WCVB
Encore Boston Harbor is warning that up to 1,000 employees could face furloughs as a statewide curfew for many businesses takes effect. New executive orders issued by Gov. Charlie Baker in response to the surging number of COVID-19 cases took effect Friday. Those include a 9:30 p.m. closing time for numerous business types, including indoor recreation. A company spokesperson confirmed that executives were trying to determine the impact of the mandatory overnight closure and considering between 670 and 1,000 furloughs."The governor of Massachusetts issued a directive limiting the operating hours of certain businesses, including restaurants and casinos, effective Nov. 6, 2020. Encore Boston Harbor may modify its operations as a result of this directive. We are currently unable to determine when these measures will be lifted," parent company Wynn Resorts wrote in a third quarter report issued Thursday. Encore was closed from March 15 through July 10 because of the pandemic. It reopened with numerous changes and restrictions on the gaming floor and throughout the resort. Some food and beverage outlets remain closed.
EVERETT, Mass. —
Encore Boston Harbor is warning that up to 1,000 employees could face furloughs as a statewide curfew for many businesses takes effect.
New executive orders issued by Gov. Charlie Baker in response to the surging number of COVID-19 cases took effect Friday. Those include a 9:30 p.m. closing time for numerous business types, including indoor recreation.
A company spokesperson confirmed that executives were trying to determine the impact of the mandatory overnight closure and considering between 670 and 1,000 furloughs.
"The governor of Massachusetts issued a directive limiting the operating hours of certain businesses, including restaurants and casinos, effective Nov. 6, 2020. Encore Boston Harbor may modify its operations as a result of this directive. We are currently unable to determine when these measures will be lifted," parent company Wynn Resorts wrote in a =" target="_blank">third quarter report issued Thursday.
Encore was closed from March 15 through July 10 because of the pandemic. It reopened with numerous changes and restrictions on the gaming floor and throughout the resort. Some food and beverage outlets remain closed.


text:
Pennsylvania School District Apologizes For Threatening To Put Children In Foster Care Over Unpaid Lunch Debt
Tim BoyleGetty Images
Connor Perrett
A school district in Pennsylvania apologized this week after sending a letter to parents earlier in the month threatening to place children in foster care if school lunch debts went unpaid, according to NPR.
The Wyoming Valley West School District in Pennsylvania also said it decided to accept a donation in the amount of $22,000 from a local CEO who offered to pay off the outstanding lunch debt. As NPR noted, the district had previously refused to accept donations to pay for the school lunches.
Per a previous report from The Inquisitr, the Pennsylvania school district sent letters to about 40 parents threatening to take them to court, which could potentially result in placing their children in foster care unless the parents paid the students' outstanding lunch debt.
As The Inquisitr noted, the letter faced harsh criticism for its tone. A person in charge of the school district's federal programs agreed that the letter was "over the top and should not have been sent out." The school board vice president said that he thought that the letter was "cringe worthy," per The Inquisitr.
Data from Census Reporter showed that 14 percent of individuals in the school district's boundaries lived at or below the poverty line, which is 10 percent higher than the rate in the rest of the state.
In an undated letter from the Pennsylvania school district, which is about three hours north of Philadelphia, the district apologized for the tone of its initial letter.
"It wasn't the intention of the district to harm or inconvenience any of the families of our school district," the letter said.
Todd Carmichael, CEO of Philadelphia-based La Colombe Coffee, offered pay late lunch bills of families that were threatened with foster care. https://t.co/roiQ2cpU66
— USA TODAY Money (@USATODAYmoney) July 23, 2019
The letter also outlined that the school board had decided to accept a donation by Todd Carmichael, who is the CEO of La Colombe Coffee Roasters in Philadelphia, per Heavy. According to Heavy, Carmichael said he was inspired to help because he received free lunches in school as a child.
Carmichael describes himself as an activist, and as Heavy notes, said he once was arrested as a college student for a protest in the '80s he organized against South African apartheid.
The new letter from the district also said that it now qualified for the Community Eligibility Program, and that all students enrolled in the district's schools would receive free breakfast and lunch for the next five years regardless of parent income.
Pennsylvania State Sen. Katie Muth, a Democrat, weighed in on Twitter on Tuesday prior to the school board's reversal on Carmichael's donation, and thanked him for his offer.
"Todd Carmichael understands the boost that services like food assistance had on his life and is trying to do his part to pay it forward," Muth wrote in a series of tweets that culminated with her shaming the school board president for initially rejecting the offer to pay off the school debt.


text:
Justia Patents Specified Output Coupling DeviceUS Patent for Light emitting semiconductor device Patent (Patent # 9,036,678)
Light emitting semiconductor device
Jul 27, 2010 - JDS Uniphase Corporation
A fiber coupled semiconductor device and a method of manufacturing of such a device are disclosed. The method provides an improved stability of optical coupling during assembly of the device, whereby a higher optical power levels and higher overall efficiency of the fiber coupled device can be achieved. The improvement is achieved by attaching the optical fiber to a vertical mounting surface of a fiber mount. The platform holding the semiconductor chip and the optical fiber can be mounted onto a spacer mounted on a base. The spacer has an area smaller than the area of the platform, for mechanical decoupling of thermally induced deformation of the base from a deformation of the platform of the semiconductor device. Optionally, attaching the fiber mount to a submount of the semiconductor chip further improves thermal stability of the packaged device.
Latest JDS Uniphase Corporation Patents:
UPGRADING A PROGRAMMABLE LOGIC GATE ARRAY IN AN IN-SERVICE PLUGGABLE TRANSCEIVER
METAL-DIELECTRIC OPTICAL FILTER, SENSOR DEVICE, AND FABRICATION METHOD
BIDIRECTIONAL LONG CAVITY SEMICONDUCTOR LASER FOR IMPROVED POWER AND EFFICIENCY
Provision of frames or borders around pigment flakes for covert security applications
Reconfigurable optical add/drop multiplexor and optical switching node
The present invention claims priority from U.S. Provisional Patent Application No. 61/229,171, filed Jul. 28, 2009, which is incorporated herein by reference.
The present invention relates to light-emitting semiconductor devices, and in particular to assembly and a thermal packaging of fiber-coupled light-emitting semiconductor devices.
Light-emitting semiconductor devices, such as laser diodes, laser diode arrays, and light emitting diodes (LEDs), are frequently used in conjunction with optical fibers for delivering emitted light to external objects. The efficiency of optical coupling between a semiconductor chip and an optical delivery fiber must be maintained during normal operation of the fiber coupled semiconductor device. The efficiency of optical coupling must also be maintained during assembly and packaging of the fiber coupled semiconductor device, to maximize light generation efficiency of the manufactured device.
A light emitting area of most semiconductor chips is quite small, measuring only a few microns in a direction perpendicular to a plane of thin film layers of the semiconductor device. Generally, small size of the light emitting area is a good, desirable property of a light source, because it is associated with high brightness of the source, allowing the light from the source to be tightly focused, for example. To preserve the brightness of the semiconductor source, it is preferable to use optical fibers having small core diameter. Due to small dimensions of the light emitting area and the small fiber core diameter, the optical fiber has to be precisely aligned to the semiconductor chip. Furthermore, to maintain the emitted power level over a lifetime of the device, the precise alignment between the optical fiber and the semiconductor chip must be maintained over the lifetime of the device.
Referring to FIG. 1, a prior-art fiber-coupled laser diode assembly 10 is shown. The laser diode assembly 10 has been disclosed by Ziari et al. in U.S. Pat. No. 6,758,610 assigned to JDS Uniphase corporation and incorporated herein by reference. The laser diode assembly 10 includes a base 11, a laser chip submount 12, a laser chip 13, a fiber sub-mount 14 including a top section 14A, and an optical fiber 15. The submounts 12 and 14 are affixed to the base 11 with solder layers 16, and the laser chip 13 is affixed to the laser chip submount 12 with the solder layer 16. A solder bead 17 is used to connect the optical fiber 15 to the fiber submount 14. The fiber 15 is metalized to have a metallization layer 18 for improving wettability of the optical fiber 15 by the metal solder material of the bead 17. The top section 14A has low thermal conductivity to serve as a thermal barrier during soldering operation. A front surface 19 of the optical fiber 15 is lensed to improve fiber coupling efficiency.
The optical fiber 15 is aligned to the laser chip 13 using a precision translation stage, not shown. During alignment, the laser chip 13 is energized to produce light, and the optical power of light coupled into the optical fiber 15 is measured. The optical fiber 15 is translated using the translation stage until the coupled optical power is maximized. Then, the melted bead 17 is applied to fix the fiber position. During the cooling down, however, the thermally induced stresses in the submounts 12 and 14, the laser chip 13, and the optical fiber 15 misalign the fiber 15, which results in a loss of some optical power coupled into the optical fiber 15.
Further, disadvantageously, the fiber coupling efficiency of the laser diode assembly 10 is dependent on the ambient temperature even in cases when the laser diode assembly 10 is temperature stabilized using a thermoelectric cooler (TEC). The TEC is not shown in FIG. 1. To remove the heat from the laser diode assembly 10, the base 11 is attached to a top surface of the TEC, and a bottom surface of the TEC is connected to an external heat sink, not shown. When the ambient temperature is different from the temperature of the base 11 of the laser diode assembly 10, the inside and the outside surfaces of the TEC are at different temperatures. The temperature difference results in deformation of the inside TEC surface on which the base 11 is mounted, which causes the base 11 of the laser diode assembly 10 to deform. The deformation of the base 11 results in misalignment of the optical fiber 15 relative to the laser diode chip 13, which results in a reduction of optical fiber coupling efficiency, leading to a reduction of output optical power and the conversion efficiency of the laser diode assembly 10.
Massey in U.S. Pat. No. 7,293,922, which is incorporated herein by reference, discloses a so called "laser hammering" method, which can be used to make fine adjustments of alignment of soldered optical fibers. By way of example, laser hammering can be used to align the fiber 15 to the laser diode chip 13 after cooling down of the solder bead 17, to mitigate the loss of the coupling efficiency due to the thermally induced stresses in the submounts 12 and 14 created upon cooling of the assembly. This approach requires expensive equipment and is limited in its ability to restore the lost coupling efficiency due to somewhat random nature of the effect of the laser pulses.
In U.S. Pat. No. 5,682,453, incorporated herein by reference, Daniel et al. disclose a method of bonding optical elements using glass-based bonding compounds including glass particles and a binding agent. When heat is applied, the binding agent burns away leaving the glass particles fused together. The heat may be applied using a laser. Disadvantageously, a considerable amount of heat needs to be applied locally to melt or at least "soften" the glass particles, so they can be fused together. Local heating is known to create an internal mechanical stress in a system.
In U.S. Pat. No. 6,075,914, incorporated herein by reference, Yeandle discloses an apparatus for connecting an optical fiber to an optical device. In the apparatus of Yeandle, the optical fiber is secured at a location remote from the fiber tip, and the fiber tip is placed in a V-groove to define its position. The heating of the fiber tip is thus avoided. Disadvantageously, this method is limited to passive fiber alignment, which is generally applicable for aligning multimode fibers having a relatively large core diameter.
In U.S. Pat. Nos. 6,734,517 and 7,030,422, incorporated herein by reference, Miyokawa et al. disclose a semiconductor laser diode module constructed so as to reduce the temperature dependence of the fiber coupling efficiency. In the semiconductor laser diode module of Miyokawa et al., the material of a base for supporting a laser chip is selected to match that of a fiber holder. Further, the fiber holder has two parts, one of which is mounted to the base and the other supports the fiber ferrule. The part that is mounted to the base is shaped so that it does not interfere with the laser diode mounting region of the base. Disadvantageously, the module of Miyokawa et al. is rather complex, requiring many laser welding spots to affix all the parts of all the holder elements.
It is a goal of the present invention to provide a simple and inexpensive fiber coupled semiconductor device, in which the fiber coupling efficiency exhibits no substantial decrease both at the aligning/packaging stage and during normal operation. It is also a goal of the invention to provide a method of assembly of such a device.
In accordance with the invention there is provided a method of assembly of a semiconductor device, comprising:
(a) providing a semiconductor device subassembly including a platform and a semiconductor chip extending in a first plane, the semiconductor chip thermally coupled to the platform for removing heat from the semiconductor chip;
(b) attaching a fiber mount to the semiconductor device subassembly, the fiber mount having a fiber mounting plane;
(c) optically coupling an optical fiber to the semiconductor chip for receiving light therefrom, wherein the optical fiber extends parallel to the fiber mounting plane;
wherein step (c) includes attaching the optical fiber to the fiber mount, so that the first plane is perpendicular to the fiber mounting plane, whereby a change of the optical coupling upon attaching the optical fiber to the fiber mount is lessened.
In accordance with another aspect of the invention there is further provided an assembly comprising:
a semiconductor device subassembly including a platform and a semiconductor chip extending in a first plane, the semiconductor chip thermally coupled to the platform for removing heat from the semiconductor chip;
a fiber mount attached to the semiconductor device subassembly, the fiber mount having a fiber mounting plane; and
an optical fiber attached to the fiber mount in the fiber mounting plane and optically coupled to the semiconductor chip for receiving light therefrom, wherein the optical fiber extends parallel to the fiber mounting plane;
wherein the first plane is perpendicular to the fiber mounting plane, whereby a dependence of the optical coupling between the semiconductor chip and the optical fiber on temperature of the assembly is lessened.
In one embodiment, the platform is mounted on a spacer mounted on a base. A platform mounting area is smaller than a total area of a bottom surface of the platform, to reduce sensitivity of fiber alignment to a deformation of the base. In another embodiment, the semiconductor device chip is mounted on a submount. The fiber mount can be attached directly to the submount, to reduce sensitivity of fiber alignment to a deformation of the platform.
In one embodiment, the semiconductor chip is a diode laser chip. The invention can also be applied to packaging of other devices, such as light emitting diodes, for example.
Exemplary embodiments will now be described in conjunction with the drawings in which:
FIG. 1 is a side view of a prior-art fiber-coupled laser diode assembly;
FIGS. 2A and 2B are side cross-sectional views of two embodiments of a semiconductor device assembly of the invention;
FIG. 3 is a three-dimensional view of the assembly of FIG. 2A;
FIG. 4A is an isometric view of the assembly of FIG. 2A showing attachment of a lensed optical fiber to a vertical plane;
FIG. 4B is a frontal view the lensed optical fiber of FIG. 4A;
FIG. 4C is a magnified isometric view of the assembly of FIG. 2A;
FIG. 4D is a dependence of optical coupling efficiency on fiber tip offset in the assembly of FIG. 2A;
FIG. 4E is a measured change of optical coupling efficiency during assembly of a number of prototypes of the semiconductor device of FIG. 2A;
FIG. 5A is a three-dimensional view of the laser diode assembly of FIG. 2B mounted on a thermo-electric cooler (TEC) showing, in exaggerated form, a deformation of the TEC;
FIG. 5B is a three-dimensional view of the laser diode assembly of FIG. 5A packaged into a butterfly package;
FIG. 6 a side cross-sectional view of a semiconductor device assembly of the invention having fiber mount attached to the laser diode chip submount; and
FIG. 7 is a side view of the semiconductor device assembly of FIG. 6 mounted on a thermo-electric cooler assembly.
While the present teachings are described in conjunction with various embodiments and examples, it is not intended that the present teachings be limited to such embodiments. On the contrary, the present teachings encompass various alternatives, modifications and equivalents, as will be appreciated by those of skill in the art.
Referring to FIG. 2A, a semiconductor device assembly 20A of the present invention includes a semiconductor device subassembly 23, a fiber mount 26 attached to the semiconductor device subassembly 23, and an optical fiber 27 attached to the fiber mount 26. The semiconductor device subassembly 23 includes a platform 24, a submount 28 mounted on the platform 24, and a semiconductor chip 25 mounted on the submount 28. The semiconductor chip 25 is thermally coupled to the platform 24 through the submount 28. The semiconductor chip 25 is optically coupled to the optical fiber 27 to receive light from an active layer, not shown, of the semiconductor chip 25. The submount 28 is optional. When a submount is not used, the semiconductor chip 25 is mounted directly on the platform 24.
The active layer of the semiconductor chip 25 extends in a plane, which is perpendicular to a mounting plane of the optical fiber 27. For example, in the side view of FIG. 2A, the plane of the active layer is horizontal, and the fiber mounting plane is vertical, that is, parallel to the plane of FIG. 2A. The vertical mounting of the optical fiber 27 reduces thermal dependence of the optical coupling between the horizontally mounted semiconductor chip 25 and the optical fiber 27. An explanation of this advantageous effect will be given further below.
The semiconductor chip 25 is preferably a laser diode chip, but it can be any other type of a semiconductor chip that emits or amplifies light, for example a light-emitting diode (LED) chip or an optical semiconductor amplifier (OSA) chip. The fiber 27 is preferably a lensed optical fiber having an anamorphic fiber lens at its tip for improving optical coupling between the semiconductor chip 25 and the fiber 27. A separate lens can also be used. Alternatively, the fiber 27 can be butt-coupled to the semiconductor chip 25.
Turning to FIG. 2B, a mounted semiconductor device assembly 20B of the present invention includes the semiconductor device assembly 20A mounted on a spacer 22 mounted on a base 21. The bottom surface of the platform 24 includes a mounting area in contact with the spacer 22. The mounting area of the platform 24 is smaller than a total area of the bottom surface of the platform 24, such that a deformation of the base 21 does not impart, or at least reduces, a deformation of the platform 24. For example, a length of the mounting area of the platform 24 on the spacer 22 can be between 30% and 80% of a total length of the bottom surface of the platform 24. The lengths are measured in a direction of a length of the optical fiber 27. This is sufficient to reduce the deformation of the platform 24. As a result, sensitivity of the optical coupling between the semiconductor chip 25 and the optical fiber 27 to a deformation of the base 21 is lessened. Since the deformation of the base 21 is caused by a change of ambient temperature, as explained above, the sensitivity of the optical coupling to ambient temperature changes is also lessened.
In one embodiment, a length of the mounting area of the submount 28 on the platform 24 is between 30% and 80% of the length of the mounting area of the platform 24 on the spacer 22. These lengths are also measured in the direction of the length of the optical fiber 27. It is also desirable that the submount mounting area be disposed directly over the platform mounting area, as shown in FIG. 2B. Both of these structural features result in lessening of mechanical stress at the semiconductor chip 25 and improve optical stability.
The spacer 22 is preferably made of a material with high thermal conductivity, such as aluminum nitride or copper. By way of example, the thermal conductivity of the spacer 22 can be greater than 200 W/m*K, but preferably between 200 W/m*K and 400 W/m*K. The base 21 can be made of an inexpensive steel, although other materials can also be used.
Referring again to FIG. 2B, the semiconductor device assembly 20B can be manufactured by providing the base 21 and the spacer 22, mounting the spacer 22 on the base 21, and mounting the platform 24 on the spacer 22 so that the platform mounting area is smaller than a total area of the bottom surface of the platform 24 as explained above. The spacer 22 can be mounted first to the platform 24 or to the base 21.
Referring now to FIG. 3, a packaged semiconductor device assembly 30 includes the semiconductor device assembly 20A mounted on a thermoelectric cooler (TEC) 31 and packaged into a butterfly package 32 having a fiber feedthrough 33 and electrodes 34 for feeding electrical connections to the semiconductor chip 25 and the TEC 31 through the butterfly package 32 to an external controller of the laser diode assembly 30.
Referring now to FIGS. 4A to 4C, the semiconductor chip 25 is disposed in the XZ plane, as XYZ coordinate system 40 indicates. The optical fiber 27 is attached to a vertical surface 41 of the fiber mount 26, disposed in the YZ plane. Thus, the plane of the active layer of the semiconductor device 25 is perpendicular to the plane of the vertical mounting surface 41, to which the optical fiber 27 is mounted. This geometry of fiber attachment results in improved stability of optical coupling during the assembly process, for the following reason.
The optical fiber 27 is attached, preferably using an ultraviolet curable (UV curable) epoxy 42, to the vertical surface 41. When the fiber 27 is attached, it bends somewhat in the XZ plane due to shrinking of the UV epoxy 42 upon cure, as well as due to thermal mismatches between the fiber 27, the fiber mount 26, and the cured UV epoxy 42. The bending results in movement of a tip of the fiber 27 along the X axis. If the fiber 27 were attached to a horizontal surface (parallel to the XZ plane), as is common in the prior art and as is in fact shown on the prior-art FIG. 1, then the fiber tip would be moving along the Y axis. However, moving along the Y axis results in a bigger decrease of the fiber coupling efficiency, because the spot size of the light emitting area of the semiconductor chip 25 is almost always smaller in the Y-direction than in the X-direction. Therefore, mounting the fiber 27 to the vertical surface 41 of the fiber mount 26 results in an improvement of stability of the optical coupling in the semiconductor device assembly 20A. Advantageously, the improved stability is observed not only during building of the semiconductor device assembly 20A, but also during normal operation of the semiconductor device assembly 20A or the mounted semiconductor assembly 20B.
Referring specifically to FIG. 4B, the optical fiber 27 is preferably a lensed optical fiber having an anamorphic fiber lens 27A at its tip for improving the coupling efficiency. The fiber lens 27A is preferably anamorphic because, as noted above, the semiconductor chip 25 has an anamorphic light field, which needs to be coupled into the round optical fiber 27. The anamorphic fiber lens 27A has mutually orthogonal first and second optical planes parallel to the XZ and YZ planes. The focal length of the anamorphic fiber lens 27A in the first plane is generally different from the focal length in the second plane.
The anamorphic fiber lens 27A is preferably a chisel lens or an angle chisel lens or a biconic lens. The angle chisel lens can have a focusing power in both optical planes or only in one optical plane. A cylindrical lens is also considered to be an anamorphic lens. Furthermore, a non-anamorphic fiber lens, such as a less expensive conical lens formed at the fiber tip, can also be used in place of the anamorphic fiber lens 27A.
Referring now to FIG. 4D, measured normalized optical coupling efficiency is graphed as a function of a lateral offset of the lensed fiber tip 27A in the semiconductor device assembly 20A. For this particular example, an angle chisel lens was used. A bell-shaped function 43 corresponding to the X-offset of the lensed fiber tip 27A is wider than a bell-shaped function 44 corresponding to the Y-offset of the lensed fiber tip 27A. As explained above, mounting of the optical fiber 27 to the vertical surface 41 of the fiber mount 26 results in fiber predominantly shifting in the X-direction and not in the Y-direction. Due to the fact that the X-offset function 43 is not as steep as the Y-offset function 44, the stability of optical coupling of the fiber 27 to the semiconductor chip 25 is improved when the optical fiber 27 is attached to a vertical surface, such as the vertical surface 41 of the fiber mount 26.
The fiber 27 is actively aligned by holding the fiber 27 with mechanical tweezers, not shown, to achieve maximum coupling of the light emitted by the semiconductor chip 25 into the fiber. Once the desired position is obtained, the UV curable epoxy fluid 42 is dispensed between the fiber 27 and the fiber mount 26.
The UV epoxy 42 is cured using a UV light source. For improved uniformity of curing, the fiber mount 26 can be made out of a material substantially transparent to UV light emitted by the UV light source. Herein, the phrase "substantially transparent" is taken to mean transparent enough, so that the UV epoxy 42 is uniformly cured. For example, the fiber mount 26 can be made out of a borosilicate glass having a 90% transparency at a wavelength of 360 nm.
Upon UV curing the UV epoxy 42, the fiber 27 is released from the tweezers, and the semiconductor device assembly 20A is preferably post-cured at an elevated temperature. It is crucial that at this step the fiber coupling does not change; for this reason, an epoxy with low shrinkage upon cure (less than 1% of shrinkage), and low coefficient of thermal expansion (6 ppm/° C. to 20 ppm/° C.) should preferably be used. During the post-cure, the temperature should be ramped up slowly, for example at a rate of 0.5 to 2.0 degrees per minute.
According to one embodiment of the invention, the UV curing is preferably performed at an elevated temperature higher than ambient temperature, for example between 35° C. and 70° C., preferably at 65° C., for increasing the resulting glass transition temperature of the cured UV epoxy 42 so that its glass transition temperature of the cured UV epoxy 42 exceeds the ambient temperature before releasing the tweezers. It is further preferable to match thermal expansion coefficient of the fiber mount 26 to a thermal expansion coefficient of the semiconductor device subassembly 23 to within 5 ppm/° C., for reducing a change of the optical coupling upon curing of the UV epoxy 42 at the elevated temperature. For example, when the thermal expansion coefficient of the semiconductor device subassembly 23 is 4 ppm/° C., the fiber mount 26 should preferably have a thermal expansion coefficient of less than 9 ppm/° C.
Turning to FIG. 4E, the results of measuring stability of optical coupling in a number of manufactured prototypes of the semiconductor device assembly 20A are presented. In FIG. 4E, a normalized change of coupled optical power is plotted for the "Pre-Align", "Post-Epoxy Dispense", "Post UV Cure", Post Heat Cure", "Post Fiber Seal", and "Post Lid Seal" stages of the assembly. It is seen that the biggest drop of the coupled optical power occurs upon UV curing. Nonetheless, in approximately 50% of cases, the coupled power increased somewhat upon the post-cure, probably due to release of internal stresses. The overall coupled optical power drop was less than 9%, being less than 5% in most cases. In comparison, the power drop after post cure was greater than 20% in the case where the fiber 27 was epoxied to a top surface of the fiber mount 26, as is normally done in the prior art. The results shown in FIG. 4E demonstrate that mounting the optical fiber 27 according to the present invention resulted in the optical coupling stability improvement of at least 4 times in most cases (from 20% to 5% coupled optical power drop), and at least 2 times in all cases (from 20% to 9% coupled optical power drop).
Referring now to FIG. 5A, a mounted semiconductor device assembly 50A includes the mounted semiconductor device assembly 20B of FIG. 2B, having the spacer 22, the platform 24, the submount 28, the semiconductor device chip 25, the fiber mount 26, and the optical fiber 27. A thermoelectric cooler (TEC) 59 is an alternative embodiment of the base 21. The TEC 59 is mounted on an external heat sink 58. The TEC 59 is required to maintain the semiconductor device chip 25 at a working temperature, and the external heat sink 58 is required to remove the heat released during TEC operation. The TEC 59 is shown deformed due to the temperature difference created by TEC operation, as explained above. The deformation of the TEC 59 is exaggerated to illustrate the advantage of using the spacer 22 to make sure that the platform 24 is not deformed upon deformation of the TEC 59, whereby sensitivity of the optical coupling between the semiconductor chip 25 and the optical fiber 27 to deformation of the TEC 59 is lessened.
Turning to FIG. 5B, a packaged laser diode assembly 50B includes the mounted semiconductor device assembly 50A of FIG. 5A and a butterfly package 51 (only partially seen in FIG. 5) for enclosing the semiconductor device assembly 50A, wirebonds 52 for providing necessary electrical connections, and electrodes 53 connected to the wirebonds 52, for feeding the electrical connections through the butterfly package 51 to an external controller of the laser diode assembly 50B. The TEC 59 is attached to the butterfly package 51. The butterfly package 51 is an alternative embodiment of the heat sink 58 of FIG. 5A.
Referring to FIG. 6, a semiconductor device assembly 60 has the same elements as the semiconductor device assembly 20A of FIG. 4A. One difference between the semiconductor assemblies 20A and 60 is that in the semiconductor device assembly 60, the fiber mount 26 is attached to the laser diode chip submount 28 and not to the platform 24, i.e. suspended above and separate from the platform 24. This additionally improves thermal stability of the optical coupling, because the deformation of the platform 24 has practically no impact on the position of the fiber mount 26. Preferably, the optical fiber 27 is mounted to the vertical side 41 of the fiber mount 26. Further, preferably, the optical fiber is lensed, having the anamorphic lens 27A at its tip. The spacer 22 and the base 21 are optional elements of the semiconductor device assembly 60. The platform 24 can be mounted directly into a package, such as the butterfly package 51 of FIG. 5B, or onto the TEC 59 placed inside the butterfly package 51. In one embodiment, the platform 24 is an integral part of the enclosure, in which case the spacer 22 and the base 21 may not be required.
Turning now to FIG. 7, a packaged semiconductor device assembly 70 of the invention includes the semiconductor device assembly 60 of FIG. 6. A TEC 72 is an alternative embodiment of the base 21 in FIG. 6. The TEC 72 has an upper plate 73, a plurality of Peltier elements 74, and a bottom plate 75. The TEC 72 is mounted within a hermetic package 71 having a hermetic feedthrough 76 for the optical fiber 27 and hermetic electrical feedthroughs 77 for the electrical contacts. The fiber mount 26 is connected to the submount 28. The optical fiber 27 is attached to the fiber mount 26 preferably using a UV curable epoxy. Using the UV curable epoxy is advantageous because it allows one to quickly attach elements together without heating. Of course, other types of epoxies can be used, as well as glass or metal soldering or brazing. The hermetic package 71 can be used for packaging of other embodiments of semiconductor devices of the invention, such as the semiconductor devices 20A, 20B, 30, and 50A. A non-hermetic package can also be used.
When the optional submount 28 is used in the semiconductor device assemblies 20A, 20B, 30, 50A, 50B, 60, or 70, the submount 28 can be first mounted to the semiconductor chip 25 and then to the platform 24, or the other way around. For the semiconductor device assemblies 60 and 70, the fiber mount 26 is attached to the submount 28. In general, the components of the semiconductor device assemblies 20A, 20B, 30, 50A, 50B, 60, and 70 can be affixed together using epoxying, soldering, brazing, laser welding, or any other attachment method suitable for the materials used.
1. A method of assembly of a semiconductor device, comprising:
(a) providing a semiconductor device subassembly having a chip mounting surface and including a platform and a semiconductor chip mounted flat on the chip mounting surface and thermally coupled to the platform for removing heat from the semiconductor chip;
(b) attaching a fiber mount to the semiconductor device subassembly, the fiber mount having a planar fiber mounting surface;
(c) optically coupling an optical fiber to the semiconductor chip for receiving light therefrom, wherein the optical fiber extends lengthwise parallel to the fiber mounting surface and the chip mounting surface; and
(d) attaching a bare section of the optical fiber directly to the fiber mounting surface,
wherein the fiber mounting surface is disposed perpendicular to the chip mounting surface, whereby a change of the optical coupling upon attaching the optical fiber to the fiber mount is lessened.
2. The method of claim 1, wherein step (d) includes epoxying the bare section of the optical fiber directly to the fiber mounting surface.
3. The method of claim 2, wherein step (d) includes curing a UV curable epoxy with a UV light source.
4. The method of claim 3, wherein the fiber mount is substantially transparent to UV light emitted by the UV light source.
5. The method of claim 3, wherein in step (d) includes heating the UV curable epoxy to an elevated temperature higher than ambient temperature, for increasing a glass transition temperature of the UV curable epoxy.
6. The method of claim 5, wherein the UV curable epoxy is heated to a temperature between 35° C. and 70° C.
7. The method of claim 5, including matching a coefficient of thermal expansion of the fiber mount to a coefficient of thermal expansion of the semiconductor device subassembly to within 5 ppm/° C., for reducing a change of the optical coupling upon curing of the UV curable epoxy at the elevated temperature.
8. The method of claim 1, wherein step (a) includes
(i) providing a submount including a top surface comprising the chip mounting surface, and a bottom surface disposed opposite the top surface, the bottom surface having a submount mounting area;
(ii) mounting the semiconductor chip directly on the chip mounting surface of the submount;
(iii) mounting the submount mounting area directly on the platform, for supporting the semiconductor chip and for thermally coupling the semiconductor chip to the platform;
wherein in step (b), the fiber mount is attached directly to the submount, whereby sensitivity of the optical coupling between the semiconductor chip and the optical fiber to deformation of the platform is lessened.
9. The method of claim 8, wherein the platform has a bottom surface with a platform mounting area, the method further including
(e) providing a thermoelectric cooler and a spacer;
(f) mounting the spacer on a top surface of the thermoelectric cooler; and
(g) mounting the platform mounting area on the spacer, so that the platform mounting area is smaller than each of: a total area of the bottom surface of the platform; and a total area of the top surface of the thermoelectric cooler, whereby sensitivity of the optical coupling between the semiconductor chip and the optical fiber to deformation of the thermoelectric cooler is lessened.
10. The method of claim 9, wherein in step (g), the platform mounting area and the bottom surface of the platform each have a length in a direction of a length of the optical fiber, wherein the length of the platform mounting area is between 30% and 80% of the length of the bottom surface of the platform.
11. The method of claim 1, wherein step (d) includes glass soldering the bare section of the optical fiber directly to the fiber mounting surface.
12. An assembly comprising:
a semiconductor device subassembly having a chip mounting surface and including a platform and a semiconductor chip mounted flat on the chip mounting surface and thermally coupled to the platform for removing heat from the semiconductor chip;
a fiber mount attached to the semiconductor device subassembly, the fiber mount having a planar fiber mounting surface; and
an optical fiber having a bare fiber section attached directly to the fiber mounting surface and optically coupled to the semiconductor chip for receiving light therefrom, wherein the optical fiber extends lengthwise parallel to the fiber mounting surface and the chip mounting surface;
wherein the fiber mounting surface is disposed perpendicular to the chip mounting surface, whereby a dependence of the optical coupling between the semiconductor chip and the optical fiber on temperature of the assembly is lessened.
13. The assembly of claim 12, wherein the bare fiber section of the optical fiber is attached directly to the fiber mounting surface with an epoxy.
14. The assembly of claim 13, wherein the epoxy is a UV curable epoxy.
15. The assembly of claim 14, wherein the fiber mount is substantially transparent to UV light for curing the UV curable epoxy.
16. The assembly of claim 15, wherein a coefficient of thermal expansion of the fiber mount differs from a coefficient of thermal expansion of the semiconductor device subassembly by less than 5 ppm/° C.
17. The assembly of claim 12, wherein the optical fiber is a lensed optical fiber having an anamorphic fiber lens having mutually orthogonal first and second optical planes parallel to the chip mounting surface and the fiber mounting surface, respectively.
18. The assembly of claim 12, wherein the semiconductor device subassembly further includes a submount including opposed top and bottom surfaces, wherein the top surface includes the chip mounting surface on which the semiconductor chip is mounted, and wherein the bottom surface includes a submount mounting area for mounting the submount directly on the platform, for thermally coupling the semiconductor chip to the platform.
19. The assembly of claim 18, wherein the fiber mount is attached directly to the submount, whereby a dependence of the optical coupling between the semiconductor chip and the optical fiber on temperature of the assembly is lessened.
20. The assembly of claim 19, wherein the platform has a bottom surface with a platform mounting area, the assembly further including a thermoelectric cooler and a spacer mounted on a top surface thereof,
wherein the platform mounting area is mounted on the spacer; and
wherein the platform mounting area is smaller than each of: a total area of the bottom surface of the platform; and a total area of the top surface of the thermoelectric cooler, whereby sensitivity of the optical coupling between the semiconductor chip and the optical fiber to deformation of the thermoelectric cooler is lessened.
21. The assembly of claim 20, wherein the platform mounting area and the bottom surface of the platform each have a length in a direction of a length of the optical fiber, wherein the length of the platform mounting area is between 30% and 80% of the length of the bottom surface of the platform.
22. The assembly of claim 21, wherein the submount mounting area is disposed over the platform mounting area.
23. The assembly of claim 12, wherein the semiconductor chip is a laser diode chip.
24. The assembly of claim 12, wherein the bare fiber section of the optical fiber is attached directly to the fiber mounting surface with a glass solder.
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Assignee: JDS Uniphase Corporation (Milpitas, CA)
Inventors: Reddy Raju (Fremont, CA), Richard L. Duesterberg (Mountain View, CA), Jay A. Skidmore (San Jose, CA), Prasad Yalamanchili (Santa Clara, CA), Xiangdong Qiu (Cupertino, CA)
Primary Examiner: Julio J Maldonado
Assistant Examiner: Joshua King
Current U.S. Class: Specified Output Coupling Device (372/108); Particular Temperature Control (372/34); Heat Sink (372/36); Integrated Optical Circuit (385/14); Optical Fiber To A Nonfiber Optical Device Connector (385/88); Fiber Holder (i.e., For Single Fiber Or Holding Multiple Single Fibers Together) (385/137); Packaging (e.g., With Mounting, Encapsulating, Etc.) Or Treatment Of Packaged Semiconductor (438/26); Having Additional Optical Element (e.g., Optical Fiber, Etc.) (438/27); With Reflector, Opaque Mask, Or Optical Element (e.g., Lens, Optical Fiber, Index Of Refraction Matching Layer, Luminescent Material Layer, Filter) Integral With Device Or Device Enclosure Or Package (257/98); With Housing Or Encapsulation (257/433); With Provision For Cooling The Housing Or Its Contents (257/712); Assembling Semiconductor Devices, E.g., Packaging , Including Mounting, Encapsulating, Or Treatment Of Packaged Semiconductor (epo) (257/E21.499)
International Classification: H01S 3/08 (20060101); G02B 6/42 (20060101); H01S 5/022 (20060101); H01S 5/024 (20060101);


Arthur Shawcross serial killer who was paroled and went on to kill prostitutes dumping their remains in and around the Genessee Rive. Shawcross died in prison on November 10, 2008. Poem titled 'A Friend'. Signed, "Arthur J. Shawcross".


What does a man my age have to offer the trend-setting generation?
Sir William Osler, in an address given at Johns Hopkins University in 1905, declared men over the age of 60 to be useless. "My second fixed idea is the uselessness of men above 60 years of age, and the incalculable benefit it would be in commercial, political, and professional life, if, as a matter of course, men stopped work at this age."
His remarks created an international furor. An influential physician, Osler was 56 years of age at the time. I don't know if he followed his own advice.
Since I am one year into Uselessness, I have been tempted to feel uncool, outdated, and passed-by. Even in the church, the attention and the agenda is directed by people well under the age of 40. One wonders if Osler was more a prophet than a crank. The race does go, it seems, to the swift and the young.
But I don't need the sight of younger, edgier leaders to feel that way. My body and consciousness whisper their own insults and accusations. When I was young, I clenched my fists and wept when I read Dylan Thomas's lines to his aging father: "Old age should burn and rave at the close of day; / Rage, rage against the dying of the light." Now, I would rage against the dying of the light-if only I could stay awake after 9:00 P.M.
As I write, I'm considering an invitation to attend tonight a beach bonfire and barbecue some male students are terming a "Viking Feast." It's an end-of-the-year, Saturday-before-finals-week celebration. I am honored by the invitation. Scrawled across the top of the invitation: "Ben! You've got to come!"
But I'm nervous about one of the requirements: "NO shirt or shoes." No shirt? I heard somewhere that the reason men my age shouldn't go shirtless in public is that it scares the children and confuses the babies. Dark thoughts now intrude: will it also amuse the young men? And still darker thoughts: who do I think I am, trying to be a shepherd to these young people?
I am overstating the problem. Working with college students has shown me that my advanced age is more a help than a hindrance. Whatever else this generation wants, it wants to know there is such a thing as older people who are reliable, available, and willing to tell the truth.
It wants to be able to trust someone the age of their parents and grandparents. Many have been wounded by infidelity and divorce. Their foundations have been shaken in other ways, too. So many are under-parented: their moms and dads have been ardent supporters of their pursuits in academics, sports, and music, but more as peer wannabes than as elders. They have been more interested in helping their children build a resume than a character. The students I know are looking for mentors.
When I first began to hear God's call to work with students, I thought I was too old for that kind of thing. I was 50, for heaven's sake. Shouldn't I have done that in my twenties instead, when I looked more like I belonged? I have since come to believe that rather than being too old now, I was too young then to be effective-or reliable. You don't ask a fish about the impurities in the water; it's too close to know. I was a child of the Sixties and, though a Christian, a reflexive leftist. I believed much of what was wrong with America could be traced to capitalism and its practitioners. The academic world seemed to me a haven of sanity and purity in an evil world populated by businessmen. I was also a disciple of rock and roll, and a narcissist. I spent too much time talkin' about my generation, hoping to die before I got old, and mistrusting anybody who did.
So what did God have me do for 22 years? Pastor churches filled with business people and some old folks. And then (gasp!) I got old. My attitudes changed in many ways, although I still like rock and roll. It has been good for Ben Patterson to get old. Wisdom doesn't necessarily come with age, but it rarely comes without it. I wasn't wise then, I'm probably not very wise now, but at least I know it in ways I simply could not as a younger pastor.
What is the wisdom in all this? It's greater than having a more nuanced worldview. It is the realization that the ministry I had then and the ministry I have now is solely because of the mercy of God. Completely. Period. My talent and maturity will never be sufficient; only the God I serve is.
I've lived long enough to see some happy endings: bodies cured, broken families restored, marriages healed, sinners saved, youths brought home from the far country. My hope in the power of God and the efficacy of prayer is firmer now than ever. I am more relaxed and focused in crisis than I once was. And there have been enough sad, tragic stories to keep me humble in that hope. Tears now come more easily. I have so many poignant, wonderful stories to tell. It goes with the territory. "Middle age makes storytellers of us all," says my friend Dan Taylor. True, the danger for the old is the temptation to garrulousness. But what a splendid temptation!
The wisdom of the long view is also the wisdom of the short view. The time left to live when old is shorter than the time left when young. It is an intense, burning personal reality. When Lou Holtz coached football at the University of Minnesota, he quipped about the Upper Midwest that though it wasn't the end of the world, you could see it from there.
As far as I know, I'm not yet at death's door, but I can see it from here, better than ever. Seeing it is good. I know by experience that seasons come and go, children grow up, dear friends get old and die. Time runs out, and the wise will pray, "Teach us to number our days aright that we may gain a heart of wisdom" (Ps. 90:12).
The wisdom of the short view helps us put the emphasis where it belongs. The Christian ministry is always more about what you let go of than what you hold on to. It's about leaving a godly legacy, about passing on to others the faith handed to us. This is no more true for the old than for the young, but the old have to be very stupid to miss it. Indeed, some are, but I don't want to be one of them. I want to care more for what I can give to those who come after me, than what I can hold on to for myself.
Theologian Karl Barth had this in mind when he wrote that extraordinary section in Church Dogmatics on the vocation of the old. He thought it foolish for the elderly to think that because they are old they may now hold back and play it safe. "As if it were permissible to freeze or solidify at the point where the river of responsibility should flow more torrentially than ever in view of the approaching falls, of the proximity of the coming Judge!"
Just as a river speeds up its pace as it nears the precipice of the falls, so old age is the time to open up to God's call. Why hold back when the time is so short?
I need to tell a story now, about Charles McCoy, a great waterfall rider. I got it from Franklin Graham's book, This One Thing I Do. McCoy was pastoring a Baptist church in Oyster Bay, New York, when at age 72 his denomination mandated his retirement. A life-long bachelor, he had cared for his mother as long as she lived. In his spare time he had earned seven university degrees, including two Ph.D.s, one from Dartmouth, the other from Columbia. But now, at 72, he was being forced out of the pastorate because he was considered too old.
He was depressed. "I just lay on my bed thinking that my life's over, and I haven't really done anything yet. I've been pastor of this church for so many years and nobody really wants me much-what have I done for Christ? I've spent an awful lot of time working for degrees, but what does that count for? I haven't won very many for the Lord."
A week later he met a Christian pastor from India, and on impulse asked him to preach in his church. After the service the Indian brother asked him matter-of-factly to return the favor. Since he had preached for McCoy, would McCoy come to India and preach for him? McCoy told him that he was being forced to retire and move into a home for the elderly down in Florida. But the Indian insisted, informing him that where he came from, people respected a man when his hair turns white. Would he come?
McCoy prayed about it and decided to go. The members of his church were aghast. The young chairman of his deacon board summed up the congregation's attitude: "What if you die in India?" I love McCoy's answer. He told him he reckoned that "it's just as close to heaven from India as it is from Oyster Bay."
He sold or gave away most of his belongings, put what was left in a trunk, and booked a one-way passage to India. It was his first trip out of the United States.
When he arrived in Bombay, he discovered to his horror that his trunk was lost. All he had were the clothes on his back, his wallet, his passport, and the address of missionaries in Bombay he had clipped from a missionary magazine before he left. He asked for directions, got on a bus, and headed for their house. When he got there, he discovered that while he was on the streetcar his wallet and passport had been stolen!
When he knocked on the door of the missionaries' house, he was greeted with a polite smile and a blank look. Not only were they not expecting him, but the man who had invited him to India was still in the U.S. and would probably remain there indefinitely.
What was he going to do now? Unperturbed, McCoy told them he had come to preach and that he would try to make an appointment with the mayor of Bombay the next day. The missionaries warned him that the mayor was very busy and that in all the years they had been missionaries there, they had never been granted an appointment with him.
Nevertheless, McCoy set out for the mayor's office the next day. When the mayor's secretary gave him McCoy's business card, listing all his degrees, he thought McCoy must not be merely a Christian pastor, but someone much more important. Not only did he get an appointment, but the mayor held a tea in his honor, and invited many of the city's influential officials.
Old Dr. McCoy was able to preach to these leaders for half an hour. Among them was the director of India's West Point, the National Defense Academy at Poona. He was so impressed at what he heard that he invited McCoy to preach there.
Thus was launched, at age 72, a brand-new 16-year ministry for Dr. Charles McCoy. Before he died at age 88, this dauntless old man circled the globe preaching the gospel. There is a church in Calcutta today because of his preaching, and a thriving band of Christians in Hong Kong because of his faithful ministry. He never had more than enough money to get him to the next place he needed to go. He died one afternoon in a hotel in Calcutta, resting for a meeting he was to preach at that evening.
Soul clap its hands and sing."


YUHSpace: What is the difference between the inferior labial artery and the horizontal labiomental artery?
What is the difference between the inferior labial artery and the horizontal labiomental artery?
BACKGROUND: The inferior labial artery (ILA) and horizontal labiomental artery (HLA) can be regarded as the main arteries used in the lower lip pedicle for the perioral reconstruction. However, the courses of the ILA and HLA are described in diverse ways, and there is no obvious standard for distinguishing between them. The aim of this study was to elucidate the distribution patterns of the ILA and HLA, and the significance of the HLA in the vascularization of the lower lip. MATERIALS AND METHODS: Sixty-three hemifaces from 18 Korean and 19 Thai cadavers were used in this study. The distribution patterns of the arteries of the lower lip area were classified based on the assumption that the HLA travels in the middle of the lower lip area, while the ILA runs along the lower lip border. The arterial distribution pattern of the HLA was classified into three types (I-III): type I, where the HLA ran horizontally in the lower lip area; type II, where the HLA curved upward to the vermilion border of the lower lip; and type III, where the HLA bifurcated into two branches. The ILA was also classified into three types (A-C): type A, where the ILA was not observed; type B, ILA was ramified from facial artery at the level of mouth corner; and type C, ILA arose from the superior labial artery (SLA) and supplied the lower lip vermillion border. RESULTS: Types I, II, and III were observed in 52.4 % (33/63), 39.7 % (25/63), and 7.9 % (5/63) of cases, respectively; and types A, B, and C were observed in 52.4 % (33/63), 36.5 % (23/63), and 11.1 % (7/63) of cases. Consideration of the two artery classifications together revealed seven types: type IA (14.3 %, 9/63), type IB (28.6 %, 18/63), type IC (9.5 %, 6/63), type IIA (30.2 %, 19/63), type IIB (7.9 %, 5/63), type IIC (1.6 %, 1/63), and type III (7.9 %, 5/63). The distance between the HLA and the midpoint between the mouth corner and the inferior mandibular margin was 0.4 ± 3.1 mm (mean ± SD) inferior to this point. CONCLUSION: The ILA and HLA should be differentiated according to the location of their origin rather than their terminating areas. The HLA could be considered as the main artery supplying the lower lip mucosa.


This method has been devised in the light of joy through the energy of empowerment. Through all other aspects of self experiencing Divinity and personal power we pull energies of ancient realisation through dimensional portals that are being experienced as omnipresence and anchor them in your Being. In other words, we pull in all the powerful aspects of the selves experienced, past and present, re-align them and activate them into the bodies of your higher levels of Transcendence and true experience, so that future experiences are more harmonious and in alignment with the life purpose and sovereign integrity of the self and others. This method (and in fact all other sessions) are devised holographically through laser light telekinetics.


text:
Straighten Up and Fly Right: Long Distance Dispersal and Motor Control in Fruit Flies
Michael Dickinson, California Institute of Technology
Michael Dickinson is the Esther M. and Abe M. Zarem Professor of Bioengineering and Aeronautics at the California Institute of Technology. After receiving his PhD from the University of Washington in 1989, Dr. Dickinson was a faculty member at the University of Chicago, the University of California, Berkeley, and the University of Washington. He joined the faculty at Caltech in 2002. Dr. Dickinson's research studies the neural and biomechanical basis of behavior in the fruit fly, Drosophila, with the goal of building an integrated model of behavior that incorporates an understanding of morphology, neurobiology, muscle physiology, physics, and ecology. Although his research focuses primarily on flight control, Dr. Dickinson is more generally interested in how animals transform sensory information into a code that controls motor output and behavior. His awards and honors include being named a MacArthur Fellow in 2001 and election to the American Academy of Arts and Sciences in 2008. His 2013 TEDxCaltech talk "How a Fly Flies" has over 1.7 million views and has been translated into 26 languages.


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