High-Frame-Rate Projection with Thousands of Frames Per Second Based on the Multi-Bit Superimposition Method

The growing need for high-frame-rate projectors in the fields of dynamic projection mapping (DPM) and three-dimensional (3D) displays has increased. Conventional methods allow for an increase in the frame rate to as much as 2,841 frames per second (fps) for 8-bit image projection, using digital light processing (DLP) technology when the minimum digital mirror device (DMD) control time is $44 \mu \mathrm{s}$. However, this rate needs to be further augmented to suit specific applications. In this study, we developed a novel high-frame-rate projection method, which divides the bit depth of an image among multiple projectors and simultaneously projects them in synchronization. The simultaneously projected bit images are superimposed such that a high-bit-depth image is generated within a reduced single-frame duration. Additionally, we devised an optimization process to determine the system parameters necessary for attaining maximum brightness. We constructed a prototype system utilizing two high-frame-rate projectors and validated the feasibility of using our system to project 8-bit images at a rate of 5,600 fps. Furthermore, the quality assessment of our projected image exhibited superior performance in comparison to a dithered image.