Techniques for laser beam sensing and profiling using temperature-sensitive structures

A laser beam detector comprising:

• a controller comprising a processor and a memory;
• a thermoelectric cooler comprising a hot side and a cold side, the thermoelectric cooler being operable to receive a series of electrical signals from the controller;
• a heat spreader comprising a cooling surface and in thermal communication with the thermoelectric cooler;
• and
• a temperature-sensitive structure in thermal communication with the heat spreader and configured to receive a laser beam, the temperature-sensitive structure comprising a plurality of thermochromic liquid crystal films, wherein each of the plurality of thermochromic liquid crystal films is characterized by a corresponding operating temperature band, and wherein:
• a region of local heating is produced on the temperature-sensitive structure in response to receiving the laser beam;
• and
• the memory stores instructions that, when executed by the processor, cause the controller to:
• generate the series of electrical signals;
• cause the thermoelectric cooler to transfer heat from the cold side to the hot side;
• and
• maintain temperatures of the region within the corresponding operating temperature band of at least one of the plurality of thermochromic liquid crystal films.