High dynamic range imaging detection based on DMD and image sensor

Digital micromirror device(DMD) which is a spatial light modulator, combined with the image sensor, is able to capture the high dynamic range image data and solve the problem of bright and dark target detection. It can extend the optoelectric imaging device's dynamic range to 130 dB or more theoretically. In order to implement the light intensity control at pixel level fast and get the high dynamic image data of the real scene in high quality, a pixel level dimming algorithm, named adaptive spatial area method was proposed. This method based on the slowly change of adjacent pixels in non-edge region, was fast convergence and suitable for driving the DMD. The diming coefficient could be found after N/I times in the worst case. Then a platform, which was controlled by FPGA, was described in the paper, and the timing analysis of the DMD driver was given below. At last, the method was tested on the platform. The results show that the adaptive spatial area method is strong enough to complete the bright and dark target detection in high dynamic range scene. It has high quality in light intensity control and strong adaptability in scenes that have light intensity change of parts.