ok. you're not talking about the aspect ratio of the senors are you?cube said:Thanks, but that article doesn't say why these sensors are called like that.
It's not even that. The sensors are specified in different formats, 1/2-inch, 1/3, 1/5 etc. Nominally this is supposed to be the diagonal measurement of the active imaging area, but in real life the active areas are much smaller than that. The number is really to help manufacturers match up lenses with sensors. There is a little table at Micron with typical nominal and actual sizes.oblomow said:ok. you're not talking about the aspect ratio of the senors are you?
Why are you CCD specs from a manufacturer. Maybe it is the sensor package, the part that needs to be soldered to a board.cube said:Google "2/3 inch sensor 11mm", for example.
Or has the answer already been found? I got lost somewhere in the middle of the thread.Sensors are often referred to with a "type" designation using imperial fractions such as 1/1.8" or 2/3" which are larger than the actual sensor diameters. The type designation 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 the usable area of this imaging plane was approximately two thirds of the designated size. This designation has clearly stuck (although it should have been thrown out long ago). There appears to be no specific mathematical relationship between the diameter of the imaging circle and the sensor size, although it is always roughly two thirds.