CCTV cameras primarily use infrared (IR) waves, especially for night vision capabilities.
Infrared light, which is invisible to the human eye, allows CCTV cameras to capture images in low-light or completely dark environments. While visible light cameras are also used, IR is crucial for 24/7 surveillance.
Here's a breakdown:
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Infrared (IR) Light: This is the most common type of wave used, particularly for night vision. IR cameras emit infrared light, which bounces off objects and is then captured by the camera's sensor. This allows for clear images even in complete darkness. Within the electromagnetic spectrum, infrared waves have frequencies above microwaves and just below red visible light.
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Visible Light Cameras: Some CCTV cameras operate using visible light, similar to standard digital cameras. However, these cameras require sufficient ambient light to function effectively.
In summary, while some CCTV cameras use visible light, the use of infrared light is essential for providing reliable surveillance, especially at night or in poorly lit conditions.
