4.0um high-power desktop FP-QCL quantum cascade laser is a continuous light laser developed by LD-PD INC. The output optical power is relatively high, and the collimated output power is several hundred milliwatts, which can meet the light source conditions for mid-infrared testing. In addition, the desktop FP-QCL laser module integrates a driver and temperature control module, and software can be used to control the temperature and working current of the tuning laser, which can make the laser work stably and maintain the accuracy of the measured values.