|Previous news story Next news story| We regularly receive
emails from readers confused as to the actual size of sensor
used in digital cameras. Sensors (CCD / CMOS) are often refered
to with an imperial fraction designation such as 1/1.8" or 2/3",
this measurement actually originates back in the 1950's and the
time of Vidicon tubes. Those who find the specification sheets
for these sensors are then even more confused about the
relationship between the fraction and the actual diagonal size
of the sensor. Inside you'll find an explanation and a table of
common sensor sizes. We'll be adding this information to our
glossary for future reference. The 'Type' designation given to
toady's CCD sensors is that it harks back to a set of standard
sizes given to TV camera tubes in the 50's. These sizes were
typically 1/2", 2/3" etc. The size designation does not define
the diagonal of the sensor area but rather the outer diameter of
the long glass envelope of the tube. Engineers soon discovered
that for various reasons t