Abstract: An optical switch of the push button type for producing a variable control signal which is proportional to the position of the push button includes a housing, having a first interior wall and a second interior wall, and a push button which extends into the interior of the housing from the exterior thereof. The push button includes a body portion disposed within the housing for movement though each of a plurality of positions, whereby changes in the position of the push button cause proportional changes in an output voltage produced by the switch. A stationary light shield is fixedly disposed within the housing between the body portion of the push button and the first interior wall of the housing, where the shield also includes a plurality of apertures. Light emitting means are disposed within the housing and between the stationary light shield and the first interior wall. Light responsive means are fixedly disposed between the stationary light shield and the body portion of the push button.

Abstract: An improved optical encoder with a simplified construction for reliable component alignment and enhanced resolution is disclosed. The encoder includes a housing with locating points, such as studs and shelves, integrally formed on inner surfaces of the housing. The locating points reliably fix the X, Y and Z axis orientation between a light detector and light source assembly. The light source assembly preferably comprises two light detectors on a single board to increase resolution. Additional features of the invention include a sealed housing and a code wheel having two concentric tracks of transmissive slots that are circumferentially offset from each other and an external cable strain relief assembly.