ডিজিটাল মুদ্রার ধারণা প্রথম কে প্রদান করেন ?
ডিজিটাল মুদ্রা
১৯৮৩ সালে ডেভিড চৌম তার গবেষণা পত্রে ডিজিটাল মুদ্রার ধারণা দিয়েছিলেন। ১৯৯০ সালে তিনি ডিজিক্যাশ (DigiCash) একটি ইলেকট্রনিক নগদ সংস্থা (ক্যাশ কোম্পানি) প্রতিষ্ঠা করেন। আমস্টারডামে তার গবেষণার বাণিজ্যিক বিকাশ ঘটানোর জন্য তিনি এটি করেন।
ক্যামেরার ইতিহাস
The concept of digitizing images on scanners, and the concept of digitizing video signals, predate the concept of making still pictures by digitizing signals from an array of discrete sensor elements. Early spy satellites used the extremely complex and expensive method of de-orbit and airborne retrieval of film canisters. Technology was pushed to skip these steps through the use of in-satellite developing and electronic scanning of the film for direct transmission to the ground. The amount of film was still a major limitation, and this was overcome and greatly simplified by the push to develop an electronic image capturing array that could be used instead of film. The first electronic imaging satellite was the KH-11 launched by the NRO in late 1976. It had a charge-coupled device (CCD) array with a resolution of (0.64 megapixels). At Philips Labs in New York, Edward Stupp, Pieter Cath and Zsolt Szilagyi filed for a patent on "All Solid State Radiation Imagers" on 6 September 1968 and constructed a flat-screen target for receiving and storing an optical image on a matrix composed of an array of photodiodes connected to a capacitor to form an array of two terminal devices connected in rows and columns. Their US patent was granted on 10 November 1970. Texas Instruments engineer Willis Adcock designed a filmless camera that was not digital and applied for a patent in 1972, but it is not known whether it was ever built. The Cromemco CYCLOPS introduced as a hobbyist construction project in 1975 was the first digital camera to be interfaced to a microcomputer.