为了在室内检测光电测试设备在某种工况下的瞄准线稳定精度、稳定器稳定精度等指标, 需通过平行光管来提供无穷远目标。设计指标要求为: 采用透射式结构, 工作波段400~700nm, D=350mm, 焦距为2.8m, 视场角为3.5°, 全视场内实现复消色差。设计采用柯克三片分离式透镜作为初始结构形式, 根据宽光谱复消色差理论, 选取玻璃材料, 利用校正光学系统色差与二级光谱的条件计算各片透镜的光焦度, 求解光学系统初始结构; 根据大口径宽光谱平行光管像差要求, 引入色球差参数以及消二级光谱参数进行优化, 通过玻璃材料匹配, 实现复消色差。设计结果: 在不引入非球面的情况下, 系统接近理论衍射极限, 全视场波像差RMS值均优于λ/22, 全视场内实现了复消色差, 满足设计指标要求。

In order to test measurement and testing instruments′ items under certain working conditions, such as the accuracy of the line of sight, the stability of the stabilizer, and other indicators, an infinity target needs to be provided by collimator. The collimator specifications are: a transmission structure, a working wavelength of 400~700nm, D=350mm, the focal length of 2.8m, field of view of 3.5°, and the achromatic must be corrected in the full field of view. This design owns highlight point at figuring out the apochromatism optical structure which based on the wide spectrum apochromatic theory,accepted the Cook Three-piece Lens as initial structure to calculate their focal power respectively. According to the requirements of optical system of correcting aberration with large-aperture and wide-spectrum, the chromatic spherical aberration parameters and the secondary spectrum parameters should be introduced, the purpose of apochromatic is achieved through the glass material matching. Design results: No aspherical surface is introduced into the optical system,the image quality is almost reach the theoretical diffraction-limited. The RMS value of full field wavefront aberration is better than λ/22. And the achromatic in the field of view is corrected that meet the design requirements.