Abstract: A calibration assembly employs a thermoelectric cooler to provide a calibration temperature for one calibration flag and a different calibration temperature for a second calibration flag. Either calibration flag is immediately available for insertion into the optical path when calibration of the thermal imaging device is required. Consequently, the time required to calibrate a thermal imaging device within a thermal imaging system is greatly reduced.

Abstract: A calibration assembly employs a thermoelectric cooler to provide a calibration temperature for one calibration flag and a different calibration temperature for a second calibration flag. Either calibration flag is immediately available for insertion into the optical path when calibration of the thermal imaging device is required. Consequently, the time required to calibrate a thermal imaging device within a thermal imaging system is greatly reduced.

Abstract: A door latch actuator operates a latch bolt assembly of a door. The door latch actuator employs a spring latch plunger and a dead latch plunger mounted in a housing that has a latch cavity sized to receive the spring latch bolt and the dead latch bolt pin. The spring latch plunger engages and retracts under the pressure of the spring latch bolt, and the dead latch plunger engages the dead latch bolt pin. A drive operates the plungers to first withdraw the dead latch plunger to allow the dead latch bolt pin to move to an enabling position for the spring latch bolt. Next, the drive advances the spring latch plunger and thereby the spring latch bolt in moved to a release position and the door may be opened. The drive is preferably a rotary drive using a motor driven crank and pin system. Sensors are provided to detect the position of the system. The method of the invention encompasses the operative steps of this door latch actuator, and the method can include timing steps.