There are several types of imaging sensors with different image size for CCTV cameras, the aspect ratio of CCTV camera are normally 4:3 (H:V) and 16:9 (H:V). The size of camera’s imaging sensor affects the angle of view, with the smaller sensors creating narrower angles of view when used with the same lens.

The format of the lens, however is not related to the angle of view, it merely needs to project an image which will cover the sensor, i.e., the same format of the camera or large. This also means that 1/3” cameras can use the entire range of lenses from 1/3” to 1”, for example, a 1/3” 12mm lens gives the same angle of view as a 2/3” 12mm lens does.

The latter combination also provides increased resolution and picture quality as only the center part of the lens is being used, where the optics can be ground more accurately.