About IR Light
How IR Illuminators Work With Security Cameras
IR Illuminators provide IR light that enables true Day/Night day Security Cameras to capture clear images at night or in low-light. Infrared light is invisible to the human eye. True Day/Night security cameras are sensitive to IR light and can use it to capture images. Adding infrared light to a scene significantly improves the cameras performance in low light.
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The Visible Light & Infrared Light Spectrums
We can see the world around us because objects reflect light that our eyes can see and interpret as images. Light is electromagnetic radiation ranging from ultra-violet to the far infrared. The human eye only sees a portion of the full light spectrum, from about 400nm to 700nm.
Infrared Improves Security Camera Performance in Low-Light
At night or in other low light conditions 400-700nm light is lacking. Although humans cannot see infrared light beyond 700nm wavelength, camera sensors can. Adding 850nm infrared light to a scene significantly improves the cameras performance in low-light or at night.
The IR Illuminator emits light in the infrared range of the electromagnetic radiation spectrum. With IR light, a scene that still looks dark to the human eye, is visible for security cameras with nighttime capabilities. The IR Illuminator’s LEDs act like a spot lights for the camera while remaining invisible to the naked eye.
Light in the infrared spectrum has many advantages, it is invisible to humans so does not cause light pollution in areas where visible light would be obtrusive. Perpetrators often are not aware that they are being observed because it appears dark to their eyes. Images captured using infrared light are Black & White. Only white light has the wavelengths (400nm to 700nm) that our eyes see as color.
SCENE captured with security video camera in NIGHT mode with no IR light added.
