Detection system for interruption of optical signal

Abstract

Abstract PURPOSE:To detect the interruption of optical input signal, by comparing the major signal component of the output signal of avalanche photodiode with the double frequency component. CONSTITUTION:The major signal component f0 of the avalanche photodiode 1 output and the double frequency component 2f0 are picked up from the filters 4 and 5, they are integrated at the integrators 6 and 7 respectively, and the outputs are compared at the comparator 8. Further, if the ratio of the f0 component to 2f0 component is almost 1, it is regarded as the interruption of the optical signal, and if the ratio is remarkably different, normal input of optical signal is regarded, allowing to detect the interruption of optical signal.

Inventors

• 👤 Satoshi Ikeuchi

Bibliographic Details