P-72: A Chromatic Focal Shift Measurement System for 3-Panel LCOS Color Management

The chromatic focal shift (CFS) phenomenon will reduce the quality of 3‐panel LCOS rear projection display system. The phenomenon is caused by the imaging position difference of different light wavelengths passing through the projection lens of rear projection display. In this paper, an instrument was designed and five auto‐focus algorithms were adopted for measuring the positions of CFS. The results will be discussed and compared to each other. They will provide sufficient data to correct the back focal length when aligning the position of a panel, and then optimizing the image quality in 3‐panel rear projection display, which is critical in color focusing for its high resolution.