电视图像目标模拟器变焦准直光学系统设计

Design of Zoom Collimator for Television Image Target Simulator

为了使基于数字微镜阵列(DMD)的电视图像目标模拟器满足不同视场成像系统的测试和评估,本文介绍了一种变焦准直投影光学系统的设计。此变焦系统采用二次成像结构,利用透镜组的切换来实现变焦,为了提高像质并简化结构,在设计中引入非球面,光源通过全反射棱镜(TIR)反射到DMD上。光学系统工作在近红外波段,长入瞳距使模拟器变焦系统与导引头光学系统光瞳相匹配,并为导引头、模拟器提供足够的安装空间。在变焦过程中,相对孔径保持不变。光学系统像质满足模拟器使用要求。

Television image target simulator based on the Digital Micromirror Device （DMD） is required to test and evaluate the imaging system of a varying field of view. The design of the zoom collimator for projection is introduced. The zoom system uses a reimaging configuration and switches the lenses to zoom. The aspheric surfaces are used in the optics to improve the image quality and simplify the optics configuration. The light source reflected to the DMD by the Total Internal Reflection prisms （TIR）. The optics operates over the near infrared waveband. The long entrance pupil relief of the zoom system provides the sufficient space to place the simulator and the seeker while matching the pupil of the zoom optics and the seeker optics. The optical system zooms at the constant relative aperture. The performance of the optics meets the requirement of the simulator.