Laser Components DG Inc. has manufactured silicon avalanche photodiodes (APDs) in Phoenix, Ariz., since 2004. The detectors are based on a semiconductor structure developed by the company. Its standard program includes epitaxy and reach-through Si-APDs with an active area diameter of 230 µm and 500 µm. The APD are manufactured on 4-in. wafers and are particularly suited for recognizing small amounts of light, to single photons. These APDs are delivered in TO46 housings (lens caps and integrated filters are optional), on ceramic submounts or in TO-37 cans with built-in thermoelectric coolers. They are mainly used in laser radar systems and biomedical applications. The large-area InGaAs APDs with a diameter of 200 µm are integrated into measurement systems and rangefinders. By using an internal gain of up to 10, small signals in the IR range can be detected and the measuring range of “eye-safe“ distance measurement systems can be increased significantly.