Design and feasibility test for directional diffractive optical elements for LCD-based stereoscopic systems

摘要

We introduce the concept of directional diffractive optical elements (DOEs) for LCD backlight illumination for 3D display systems. Stereoscopic images can be obtained by two camera systems. And then, they are displayed at an LCD by interlacing. To generate 3D images, the LCD is programmed to display left and right images of a stereo pair on alternate rows of pixels. The light is diffracted by the DOEs designed for splitting the viewing directions and for adjusting the size of the viewing zones. The lines are spaced with respect to the LCD pixel rows such that the left eye sees all the lines through the odd rows of the LCD, while the right eye sees them through even rows. The DOEs are designed by iterative Fourier transform algorithm for high diffraction efficiency and uniform illumination distribution. For eliminating the twin image noise, the DOEs are designed by eight-quantized levels and synthesized for generating the stereoscopic viewing region. We discuss the design issues of this method and also discuss the advantages of this method over the conventional lenticular method. We will also discuss the initial experiment of the DOE characteristics for this purpose.