Coaxial Ultra-short Focus And Large Aperture Projection Lens Design

Ultra-short-focus projection is an important direction of projection display in recent years.It is characterized by the ability to deliver larger images within a shorter distance.Because of its short projection distance,it can save space and largely overcome the problem.The problem of glare when the ordinary projector works,and it also solves the problem of the speaker blocking the picture perfectly,and increases the space for people to interact with the screen.In the future,it will be in elevator advertisement,home projection display,hotel projection display,business meeting,etc.There is a large market for applications.This kind of ultra-short focal projection lens relies on ultra-short-focus projection objective lens.The ultra-short focal objective lens has been studied by many people.Most of them use folding projection objective lens to realize ultra-short projection distance to project large images.The shaft-type optical path structure is used to design an ultra-short-focus lens with a throw ratio of 0.37.The technical difficulty of ultra-short-throw projection is to maintain a high overall projected picture brightness on the premise of ensuring image sharpness.In this paper,by using the non-imaging light cone theory to optimize the projection lens system,a large relative aperture projection lens of 1/1.35 is designed.This lens can be used for DMD chip-based projection system,and its large relative numerical aperture ensures that the projector has a very high High overall optical efficiency.The paper first introduces the high cost of processing and assembly and the maintenance of modern folding-back ultra-short-focus projection lens.Then,a super-coaxial ultra-short-focus large-aperture projection lens is successfully designed by the coaxial transmission imaging design method.Based on the PW aberration theory of predecessors,this paper combines the methods of modern optical design software optimization to successfully construct the initial structure,and then adjusts the initial structure in the optical simulation software according to the primary aberration theory.At the same time,to get an initial structure that can be used for optimization,and to further optimise the obstacles for the next step.Then,the method of controlling the light is used to optimize the lens.According to the requirements of the provided optical design indicators,the problems in the optimization are solved one by one,and an initial structure in which all the optical index parameters are qualified is quickly designed.After detailed tolerance analysis of the designed lens system,the results show that the tolerance performance is superior,the yield is high,and the energizing performance of the lens of the lens is also judged.The result shows that the lens lens has good processing performance.