Quote:
Originally Posted by theducks
TV sets were similarly distorted. Originally the CRT was round so 8" was still 8" even at 4:3. But then the tube became rectangular and Diagonal screen measurement still exists to this day  |
And a 2/3rd inch vidicon camera tube (or four thirds) wasn't the diagonal of the image area. It was the outside diameter of the tube, or even the metal ring around the end.
That's refusing to die!
https://en.wikipedia.org/wiki/Four_T...d_aspect_ratio
A Four Thirds of an inch is 33.9mm. The MFT sensor is 22.5mm diagonal.
The diagonal of the later CRTS, even monitors, was to the edge of the tube, so a 17″ CRT was really a 16″ diagonal image. At least the Plasma, LCD, OLED it's the image on monitors, but often phones or tablets use rounded up or down numbers.