Day-night cameras are essential for surveillance and security, providing high-quality images in various lighting conditions. The IR-cut filter is a critical component, ensuring accurate color reproduction during the day and enhanced sensitivity in low light. During daylight, the IR-cut filter filters out unwanted infrared radiation, allowing realistic color images. In night mode, the filter is deactivated, increasing sensitivity to light for clear images in low light. The IR-cut filter is crucial for day-night cameras, ensuring high-quality images in all lighting conditions.
To create realistic color images, color CCD or CMOS cameras use infrared (IR) cut-off filters. IR filters can efficiently block visible light, allowing only the red portion of the light spectrum to pass through. Infrared filters can transfer around 700nm to 900nm within certain visible light spectrum’s “near infrared” band, which ranges from 700nm to 2500nm. When employing such filters, you could change a tree’s green foliage to white or darken the sky above, just like you would if you were using an old film, to create unique photographs. This can be accomplished using either absorption or reflection optical techniques. A unique type of optical glass is used to create absorption filters because it can absorb near-infrared light. Infrared light is efficiently reflected using reflection-type filters, which are short-pass interference filters. Typically, CMOS cameras employ reflecting IR filters, while CCD cameras utilize adsorbing filters.
