A day and night camera is a

security camera A closed-circuit television camera is a type of surveillance camera that transmits video signals to a specific set of monitors or video recording devices, rather than broadcasting the video over public airwaves. The term "closed-circuit televisi ...

that can see the picture during the day hours, when there is enough sunlight, and during the night in total darkness or minimum illumination. A day and night camera has special lenses that allow

infrared Infrared (IR; sometimes called infrared light) is electromagnetic radiation (EMR) with wavelengths longer than that of visible light but shorter than microwaves. The infrared spectral band begins with the waves that are just longer than those ...

emission produced by infrared

LED A light-emitting diode (LED) is a semiconductor device that emits light when current flows through it. Electrons in the semiconductor recombine with electron holes, releasing energy in the form of photons. The color of the light (corresp ...

s and reflected from objects to go through and reach a CCD or CMOS chip inside the camera. As a result, the end user can see picture in total darkness at the distance of infrared emission produced by LEDs. A day and night camera can have infrared LEDs mounted on its housing or can accept the emission, produced by an infrared turret. Day and night cameras often have modifications in their

digital signal processor A digital signal processor (DSP) is a specialized microprocessor chip, with its architecture optimized for the operational needs of digital signal processing. DSPs are fabricated on metal–oxide–semiconductor (MOS) integrated circuit chips. ...

(DSP) that compensates for the difference in illumination between day and night modes. HDR technology may also be used in more expensive models to compensate for the difference in illumination between shaded and lighted areas of surveillance.

References

{{Reflist Security technology

See also

References