Design Of The Telescope System For The Zoom Eyepiece With Inverted Image Function

The application of the variable magnification telescope system becomes more and more popular and widely spread,for some of the harsh environments,the variable magnification telescope system that needs to be sealed will often integrate the inverted image and zoom into the eyepiece,which will be more favorable to make the entire telescope system realize a sealed design.This paper presents the design results of a Kepler-type telescope system consisting of an objective lens and a three-group zoom eyepiece with image-reversing function.Through the analysis of the initial structure of the objective lens and zoom eyepiece of the telephoto system,the ZEMAX software was used to optimizing the initial structure of the selected objective lens and the zoom eyepiece respectively.The obtained telescope system can achieve a zoom of 6-24 times.The objective lens field is 1.75°-7° and the focal length is 240 mm.The field of view of the zoom eyepiece is 40.3° and the zoom range is-10 to-40 mm.The transfer function curve,distortion,and chromatic aberration of magnification are all in accordance with the design requirements of the visual optical system.According to the theory of dynamic optics,the cam curve of the zoom eyepiece was designed by the Matlab software can make the eyepiece image surface stable during the zooming and the focus adjustment is smooth.The tolerances of the designed objective lens and zoom eyepiece were analyzed.At the same time,the feasibility of the even aspherical optical process of the design was analyzed.Through the analysis of the overall tolerance and process,it is finally determined that the design result is reasonable and has certain practical value.