||The lens of the camera determines the angle of view and the focus of the captured image. There are many different lens options.
||A system feature that allows the alarm dialer to take complete control of the house telephone system in the event of an alarm. This is intended to prevent an intruder from disabling the alarm system phone dialer by simply taking a phone off hook.
||A common term often used for the security zone wiring circuit. Such a zone might have multiple switches forming one continuous loop.
||Refers to very dim lighting, even 'normal' darkness. Complete darkness is 0 lux. Infared cameras work well in very low light conditions.
||Refers to the amount of light required for a camera to capture a good image. Infared cameras have very low lux.