Using Chromaticity Error Minimisation for Fast Camera Spectral Responsivity Measurement

摘要

Measuring the spectral responsivity of a camera using a monochromator is time-consuming and expensive. This work evaluates a fast responsivity measurement method, where diffraction spectrum images are captured and then used for estimating camera responsivity. An error was noticed in the previously proposed measurement method that was caused by spectroradiome-ter measurement errors and vignetting effects from the camera's lens and sensor. Therefore, a correction step using chromaticity error minimisation is presented to adjust the initial responsivity estimate. It requires a chart to be captured under a known illumination. The chromaticity error of the improved procedure is approximately one order of magnitude smaller than the original error. This enhanced method was employed to create a dataset of spectral responsivities for machine vision, photographic, and movie cameras, which is presented here.