US Patent 10054763 Optical position sensing with temperature calibration

In some embodiments, an apparatus for performing temperature-compensated measurement of a position of a lens assembly is attached to an autofocus actuator. In some embodiments, the apparatus includes a light source for emitting light in a first direction. In some embodiments, a measurement sensor is affixed for receiving light reflected from a reflector. In some embodiments, a lateral shield is affixed in a position blocking detection by the measurement sensor of light having been emitted from light source but having not been reflected from the reflector. In some embodiments, a monitoring sensor is affixed in a position relative to the light source to receive light having been emitted from light source but having not been reflected from the reflector. In some embodiments, a transverse shield is affixed in a position blocking detection by the monitoring sensor of light reflected from the reflector.