Solar Sensor

(or sun sensor), an instrument, usually of the optoelectronic type, that determines the angle of deviation of an axis of some instrument, aircraft, or space vehicle from the direction of the sun. Solar sensors are used in the orientation of astronomical instruments, in the solution of navigational problems in aviation and spaceflight, and as attitude sensors in some orientation systems. The design of a solar sensor depends on the requirements imposed on it with respect to, for example, accuracy, reliability, speed of response, and size of region viewed.