The paper describes a formation principle of the trajectory measuring array and its corresponding survey theory. The implementation of this photoelectric trajectory measuring system and the hardware design of its computer control system are mainly discussed

including algorithm and programming steps. Every independent subsystem not only works by itself

but also forms an array system according to the demand. In light of the distinction of the useful signal

it is unnecessary to use an A/D converter. The tests have shown that this system is of practical value.