高变倍比变焦光学系统设计  

Design of zoom optical system with high zoom ratio

作　　者：姚清华[1] 闫俊岑[1] 

机构地区：[1]长春工业大学,吉林长春130012

出　　处：《应用光学》2015年第5期667-672,共6页Journal of Applied Optics

基　　金：国家自然科学基金(51374040)

摘　　要：设计了一套焦距f′=10mm^500mm的高变倍比变焦光学系统。以正组机械补偿原理为基础,通过高斯光学计算,给出合理的初始结构和高斯解。系统引入2个新型非球面,使系统具有更大的自由度,并有效校正光学系统中的像差,减小系统复杂度,对实现高变倍比变焦系统尤为有利。采用一组双层谐衍射元件来校正长焦所带来的二级光谱,减少了透镜片数,使系统更加紧凑。分析了10mm^500mm焦距情况下系统的调制传递函数曲线,计算出变倍组和补偿组的变化曲线,可以看出满足机械补偿凸轮曲线的变化规律,而且曲线的变化比较平滑,能够实现平稳变焦。在奈奎斯特频率为50lp/mm时,调制传递函数曲线均在0.6以上。A high zoom ratio optical system with f′=10mm^500mm was designed.The initial structure and reasonable Gauss solution were given by Gauss optical computing based on positive mechanical compensation principle.Two novel aspheric surfaces were introduced in this system,which could provide more degrees of freedom for optical design,correct aberration in optical systems effectively,as well as the complexity of system,and this is advantageous for achieving high zoom ratio system.The second order spectrum from telephoto was corrected by a group of double-layer harmonic diffractive element,that could reduce the number of sheets of lens and make the system more compact.The curves of zoom group and the compensating group were simulated,and the modulation transfer function(MTF)curve was analyzed in the case of 10 mm to 500 mm focal length.From the above we can see that,the system can satisfy the change regulation of the mechanical compensation cam curve,the curve is smooth,and a smooth zoom is achieved.When Nyquist frequency is 50lp/mm,the MTF is greater than 0.6,and high quality image is achieved.

关 键 词：光学设计 变焦距镜头 高变倍比 新型非球面 谐衍射元件 

分 类 号：TH74[机械工程—光学工程]