WI series is a range of optical windows designed to protect telecentric lenses and collimated illuminators. Material spatter and other hazards such as dust or debris might in fact damage the lens or result in optical performance degradation. These plano-plano windows effectively shield telecentric lenses from the outside environment without affecting the quality of your imaging system because they do not cause changes in optical magnification. WI series is also compatible with CMMR mirrors, preserving the delicate optical surfaces from dust or other hazardous particles. Each window is complemented by its own CMWF holder which features a precise tightening knob that allows for easy and secure clamping. CMWF holders are needed to mount WI protective windows in front of telecentric lenses and must be ordered separately.