Patent ID: 11965869
Assignee: nan
Field: Measurement (Instruments)
Classification: CPC G | IPC G

Claim 13:
14. The method according to claim 9, wherein the photodetector is selected from the group comprising a photodiode and a phototransistor, the detection module further comprises a collimator coupled to the photodetector, and the controller module comprises a processing unit, a preprocessing amplifier, a lock in amplifier and a gain and filter stage, the processing unit selected from the group comprising a single core processing unit, a microcontroller, an application-specific integrated circuit (ASIC), a field programmable gate array (FPGA) and a programmable logic device (PLD), the lock in amplifier configured to pass a portion of each of the detection electrical signals, the portion having a fundamental frequency corresponding to a fundamental frequency of the excitation control signal.