This Auto IRIS VARI-FOCAL lens is called as "IR-Lens" and used for "Day & Night Camera' and "Ultra High Sensitivity Camera". Because of the difference of wavelength distribution between Day and Night (especially with infrared lamp), Standard CCTV lens causes Focus Shift. Our "IR-Lens" solve it with using the special optical materials. Vari-Focal lenses can select the focal length within the specified range like zoom lenses, but focus adjustment is needed after setting of the focal length. They are designed for CS-mount camera, and feature a galvanometric iris system, NO filter and adjustable mount. As the fast F-speed of F1.4 and the density of F360, it makes a high quality picture on a monitor, especially on color, and also compensates bright objects in outdoor use.