F-Theta scan lens, The lens which works in the vicinity of the focal plane is called scan lens. Under the circumstance of not changing the optical characteristics of the system, it is to change the imaging beam position. The scan lens is used in infrared industry, another name of which is flat field focus lens, or F-Theta lens. Just as its name implies, the scan lens can make all the focal points in the same flat surface.
YAG scan lenses are widely used in YAG laser marking and drilling machine. The lens is also applicable with fiber laser machines. 
YAG scan lens is used in conjunction with XY galvanometer mirror and beam expander to form a two directions scanning system. 
The AR coating is coated on the lens surface to ensure minimal power loss. The scan lens is designed with the industrial standard M85x1 screw thread. So the scan lens is more applicable for all the machines.