Most lenses on the market are designed for the visible range of the light, the part that humans can see. These are wavelengths between about 420nm and 720nm. It means the lens can focus clearly during the day, the image will become blurred at night. 

Because the wavelength of infrared light and visible light is different, the focus of the two kinds of light through the lens is different, and the image plane formed is different.

Real IR correction lenses can be clearly image during the day and night.

Lumens can offer 12MP IR correction lenses for ANPR(automatic number plate recognition).

35mm IR correction lens, F/1.6, 420nm

35mm IR correction lens, F1.6, 850nm

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