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Federal Communications Commission; controls also wireless camera system as one of the commercial broadcasting systems.


Focal Length = (Distance to subject / Width of subject) x 4.5mm

For example, if you want to watch a subject of 5.5ft width at 10ft distance with a 1/3" CCD camera, you will need a 8.0mm FL lens. That is, 10ft / 5.5ft x 4.5mm = 8.18mm . A 8.0mm FL lens mounted on 1/3" CCD camera will cover the subject you want to watch.

Optical or lens speed. Smaller f-number means faster lens.

Optical Speed is about how fast a lens collects lights and is defined by the f-number like f/1.2, f/2.0, etc. This speed is determined by the Focal Length (FL) and the Diameter (D) of a lens; f-number = FL/D.

In conclusion, the lower the f-number, the more lights reaching the camera sensor and the better the video picture. The f-numbers are usually marked at the iris rings of lenses.


Frames per second.


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