Abstract: An optical encoder assembly including at least one light source or emitter element, at least one light detector or sensor element, at least one code member including a plurality of code elements arranged along a track extending along a plane with the emitter element and the sensor element positioned on a first side of the plane, and a reflector element positioned on an opposite second side of the plane and including a reflective surface having one or more collimating reflective surface features that reflect light emitted from the emitter element to the code element and on to the sensor element.

Abstract: A vertical cavity surface emitting laser (VCSEL) operable as a signal emitter and a silicon photodetector adapted for receiving light signals co-mounted in a common canister. Also containable is a four lead header and an isolating ceramic spacer. The canister can be electrically connected to a first lead from the header. The isolating ceramic spacer is adapted for mounting of the VCSEL above the level of the photodetector within the can. The VCSEL is electrically connectable to a second and third lead from the header and the photodetector is electrically connectable to the second and a fourth lead from the header. Co-packaging of a VCSEL and photodetector in common device canisters can yield about a 20:1 contrast ratio between an object's presence in front of the sensing system. A small pattern necessary for high accuracy is provided by the system and no barrier is necessary between the emitter and detector.