Night cameras leverage infrared (IR) technology to capture images in low-light or no-light conditions. They don't "see" in the dark like humans do; instead, they utilize a different spectrum of light.
Understanding Infrared Light
Infrared (IR) light is invisible to the human eye, existing just beyond the visible red light spectrum. Many objects emit some level of IR radiation, even in complete darkness. This heat signature is what night cameras detect.
How Night Vision Cameras Function:
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Infrared Illumination: As stated in the reference, many night cameras use infrared LEDs (light-emitting diodes). These LEDs emit invisible IR light, effectively illuminating the scene. This is crucial for capturing images in extremely dark environments.
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Image Sensor: The camera’s sensor is specifically designed to be highly sensitive to infrared light. This sensor converts the infrared light into an electrical signal.
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Signal Processing: The electrical signal is then processed by the camera's electronics. This processing enhances the image, converting the infrared data into a visible image on a display screen or recording device.
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Image Display: The final result is an image displayed on the camera's monitor, showing the scene as if illuminated, even if it's completely dark to the human eye. The image often appears in shades of green or gray, reflecting the intensity of infrared radiation detected.
Types of Night Vision:
While IR-illuminated cameras are common, other night vision technologies exist, but they are beyond the scope of this answer.
