Nonlinear Correction Method for Si Photodiode Detectors and Its Application to the Electro-Optical Measurement for the PDLC Film

A corrected measurement method was investigated for the silicon (Si) photodiode detector (SPD). The measured transmittance error between the SPD and the light power meter (LPM) occurs and depends on the incident light power. In our work, the nonlinear empirical formula was derived from the measured results of the SPD and LPM. In addition, the formula was used to correct the measuring results of the polymer-dispersed liquid crystal, and the corrected results are identical to those of the LPM. The experimental results further show that the SPD is faster than the LPM when measuring electro-optical response. As a result, the corrected method is reliable for detecting a fast response by the SPD.