Linear displacement sensor

摘要

A linear displacement sensor includes a plurality of nested, telescoping sections extending between two end pieces. One end piece includes a light source such as an infrared light emitting diode (emitter), and the other end includes a light sensitive device such as a phototransistor (receiver). At least one disk having a centrally disposed aperture is secured to one of the sections and reduces and limits stray or incident light within the sensor which is reflected inside the sensor and would otherwise impinge upon the receiver. Improved accuracy and linearity is provided by this device.