Research Of Infrared Imaging Optical System With Image Scanning Mechanism

In recent years,scanning technology has received increasingly widespread application in various fields.Traditional scanning system relies on the drive provided by slewing mechanism to realize the scanning process,which usually results in large body and complicated structure.For the need of miniaturization and compactness,an infrared imaging optical system of image-space scanning mechanism is designed.This system combines the instantaneous field of view(IFOV)with the spatial scanning which allows the expansion of the field of view.Thus large-field-of-view-scan is realized,also featuring small radial size and compact structure as well as other functions.The system consists of three parts,including front objective lens set,relay lens set and tertiary imaging lens set.The movement of swing mirror enables the system to achieve large-field-of-view-scan.It is on this basis that the performance of the system is studied.The operating waveband of this scanning system is 3.7~4.8?m,the scanning field of view 15°,the value of F~#/2.0,the external dimension?190mm×260mm and the cold stop distance19.8mm.This system can be widely used in systems that require miniaturization.The theory of dynamic optics is employed to analyze the relationship between the object and image of the system.Specifically,the relationship between the object and image at the presence of swing mirror's one-dimensional movement in an ideal state and two-dimensional movement with the consideration of error margin are presented respectively.It is also concluded that the image rotates and skews if a trace of rotation towards another direction is introduced during the movement of swing mirror.