In order to eliminate the influence of the physical characteristics of the intrinsic dark current of the Positive-Negative (PN) junction in the Photoelectric Detector (PD), the detection accuracy of the PD can be improved at the same time of enhancing the detection range of the detector power and widening the detector working environment temperature. In this paper, a set of dark current compensation algorithms is designed to calibrate the PDs.

Firstly, we analyze the physical characteristics of the photodiode and the hardware circuit design of the PD to establish a mathematical model between the photogenerated current and the optical power. Then we correct the curve relationship between the optical power and the Analog Digital Convert (ADC) value of the photogenerated voltage through the mathematical model, so as to achieve the power compensation by removing the influence of the dark current power at the specific temperature point. Next, by studying the temperature characteristics of dark current, we calculate the power required to compensate for dark current under a limited number of temperature conditions. By fitting these few temperature points, we extend the compensation to a broader temperature range, thereby achieving dark current temperature compensation. Lastly, a temperature-controlled testing platform is established, utilizing an Optical Switch (OS) to regulate the incident optical power on the photodiode. The real-time incident optical power on the PD is recorded through an optical power meter. This setup allows for testing the accuracy of the PD under various temperature conditions and incident optical power levels.

The experiments show that the working temperature can be widened from －5～55 ℃ to －40～80 ℃ and the minimum detection power can be reduced from －40 to －68 dBm by using the algorithm to calibrate the photo-detector. Under the aforementioned operating temperature and detection range, the software algorithm calculates the accuracy error between the reported optical power and the actual detected optical power to be within ±1 dB.

After calibrating the PD with this algorithm, the effects of dark current and noise can be eliminated, and the detection power range and detection accuracy can be improved in a wide temperature range.