Chap.2 Lens and Image Sensor Technology
16
ICR
An ICR (IR-cut Filter Removable) is a mechanical shutter design. It is placed between the lens and the image
sensor and is controlled by a motor or an electromagnet (Figure 2.16).
Figure 2.16 Placement of ICR
When the ICR is switched on, it will block infrared light and allow only visible light to pass through. When the ICR is
switched off, infrared light will be allowed and images will turn into black-and-white mode, which is more sensitive
to infrared light (Figure 2.17).
Visible Light
Day
Night
Wave Length (nm)
Wave Length (nm)
Light Transmission
Light Transmission
Ultraviolet
invisible
invisible
Infrared
770
380
380
100
100
770
1000
1000
Wave Length (nm)
380
100
770
1000
Figure 2.17 Operation of ICR in daytime and nighttime
Summary of Contents for IP Surveillance
Page 1: ......
