Photoelectric detector system for tracking moving targets - uses continuously scanned light barriers to provide positional coordinates

摘要

The photoelectric detector is for tracking rapidly moving objects such as missiles, and consists of a coordinate plotter comprising two or more optical systems. Each system is constructed in the form of a light-curtain detector, each of which comprises a light source (2) whose beam is focused on to a rotating multiple mirror (3) placed in the focal point of a parabolic reflector (5). Between the lens and the revolving mirror is a semi-reflecting mirror (7) and photo-detector (8). At the far end of the scanned area is a triple reflector (6) from which the scanning beam is reflected back via the optical system to the photo-electric detector. The electrical output of the latter is fed to an electronic processor. The time difference between the reference point and the instant at which an object interrupts the beam, serves as a positional coordinate.