Snapshot high dynamic range imaging based on adjustable attenuation microarray mask

Abstract

High Dynamic Range Imaging Based on Attenuation Microarray Mask has broad application prospects due to its good real-time performance and small size. But at the current level of craftsmanship, it is hard to fabricate a microattenuation array mask whose attenuation rate is adjustable. This leads to the fact that the imaging dynamic range cannot adapt to changes in scene brightness in most cases. To this end, this paper proposes a novel imaging system whose dynamic range can adaptively change according to the brightness of the scene. The core components are the micro polarization array mask mounted on the CMOS surface and the on-sensor rotatable linear polarizer in front of the lens. By controlling the rotation angle of the polarizer placed before the lens, the CMOS pixel exposure can be precisely controlled. Therefore, the imaging system dynamic range can be adjusted adaptively according to the scene brightness. Through horizontal comparison with Sony’s multi-quadrant polarization chip, we determined the optimal parameters of the multi-quadrant micro-polarization array mask for extending the dynamic range. The experimental results show that the imaging performance remains consistently good even when the dynamic range of the photographed scene is large, and the dynamic range of the device can be adapted to the dynamic range of the shooting scene, so that the image after shooting and processing can always show sufficient details. By rotating the polarizer in front of the lens to a specific angle, the high dynamic imaging of the scene can be significantly improved.