Temperature compensation means for a radiometer

摘要

A radiometer for detecting and measuring components of luminescence and reflected light contained in a light beam from a target which included means for sensing the temperature of an optical filter in the radiometer and for adjusting the angular position of the mount which carries the filter in response to the sensed temperature to thereby retune the filter to its center frequency when changes in temperature occur. Longitudinal movement of an adjustment rod changes the angular position of the mount. A micrometer means manually moves the rod in one embodiment while a motor moves the rod in a second embodiment. The rod carries a means for sensing the longitudinal position of the rod (hence the rotational position of the mount) and generates a signal representative thereof. A means on the mount senses the temperature of the filter and generates a signal representative thereof. The temperature and position signals are compared by a processing circuitry which outputs an error signal if the position of the mount does not match a predetermined temperature signal. This error signal the (1) directly operates a control mechanism to move the adjustment rod which rotates the mount to a new angular position to retune the center frequency of the filter or (2) is fed to a visual indicator, which is brought back to a desired reference point by rotating the micrometer.