What does mm mean in CCTV?

pu1. If mm is large, you can see the video narrow and close, and if mm is small, you can see the video far and wide

2017-11-23

OK

pu2. Depending on the purpose, it can be considered wide-angle (~45mm), standard (6~10mm), and telephoto (12~16mm)

2017-11-23

OK

pu3. It means the angle of view, and depending on the region, the type of view is determined, but the angle of view varies depending on the sensor used

2017-11-23

OK

pu4. 3~4mm wide-angle lens: wide-range monitoring
6-8 mm standard lens: cash counter, bank, etc
12~16mm Telephoto lens: Detailed monitoring of vehicle license plate, front of safe, etc
HD-class CCTV, manual zoom lens: wide range, narrow range

2017-11-23

OK