Abstract: A proximity fuze system includes an optical ranging apparatus, a detonation circuit controlled by the optical ranging apparatus, and an explosive charge detonated by the detonation cirtcuit. The optical ranging apparatus includes a pulsed laser light source for generating target ranging light pulses and optical reference light pulses. A single lens directs ranging pulses to a target and collects reflected light from the target. An optical fiber bundle is used for delaying the optical reference pulses to correspond to a predetermined distance from the target. The optical ranging apparatus includes circuitry for providing a first signal depending upon the light pulses reflected from the target, a second signal depending upon the light pulses from the optical delay fiber bundle, and an output signal when the first and second signals coincide with each other. The output signal occurs when the distance from the target is equal to the predetermined distance form the target.

Abstract: A photodetector useful at long wavelengths where silicon normally is transparent. It includes a photodiode stage which comprises a silicide layer forming a Schottky-barrier junction with a silicon substrate and which is integrated with an amplification stage which uses a silicon transistor adapted to amplify the photovoltaic voltage derived by the photodiode stage. In the preferred embodiment, the silicide layer forms the grid of a permeable base transistor.