TL-SC3171 Surveillance Camera uses 12 IR (Infrared) LEDs light as a means to produce clear images in the dark and an industrial mechanical ICR (IR Cut-filter Removable) completely filters that light during the day ensuring vivid video as clear as you would see with the naked eye, both functions unavailable on traditional day/night cameras that resulted in poor image quality during both the day and the night. 1/4" progressive scan CMOS sensor Surveillance Camera produces clear and crisp images.