星敏感器反射式遮光罩设计

Design of specular baffle of star sensor

星敏感器主要用于探测深黑空间中的恒星,属于微弱信号的检测,视场外的太阳光和地气光是主要的杂散光源。反射式遮光罩表面以镜面反射为主,遵循反射定律,光线易于控制,因此能够通过合理的结构设计使大部分以抑制角入射的杂光返回入射空间,而且与传统遮光罩相比,加工较为容易。详细讨论了反射式遮光罩设计的基本方法,推导了一种改进型反射式遮光罩的设计公式,最后结合某星敏感器进行了仿真验证。结果表明:该遮光罩具有较佳的杂散光抑制能力/体积比,工程可实施性强,能实现观测五等星的目标。

Star sensor is the main device used for imaging the star point in space. The off-axis high- intensity light coming from the sun and earth is the main source that affects the weak signal detection. The specular baffle can reflect most of the stray light out of field back to the outer space by using optimal structure, and following reflection law. Moreover, and it is easy to manufacture compared with conventional baffle. In this paper, the principle of reflection specular baffle design was reviewed, the formula of the improved specular baffle design was deduced and an example of specular baffle design of a star sensor was cited. The results show that the improved specular baffle has smaller size, better attenuation of stay light than the traditional ones, and it provides the intensity level of a visual magnitude of Mv=＋5.