Projection displays: New technologies, challenges, and applications

摘要

The achievable color gamut and light output of projection displays based on light-emitting diodes (LEDs), phosphor conversion, and lasers are discussed. The color appearance phenomena, color-fulness, and the Helmholtz-Kohlrausch effect are discussed in the context of LED and laser illumination of projection displays, as well as some pitfalls concerning the interpretation of the Helmholtz-Kohlrausch effect. Also the laser speckle phenomenon and the characterization of it are addressed. The importance of both the American National Standards Institute (ANSI) contrast and the sequential contrast of projectors, as well as the discrepancy between measured and perceived contrasts, are explained. Visibility criteria for contouring artifacts are explained and compared with new emerging electro-optical transfer functions that are more adapted to this issue. Stereoscopic solutions and early prototypes of autostereoscopic multi-view, super multi-view projection displays, and electro-holographic displays are discussed as well as the limiting factors of these systems in the context of display resolution, and LED and laser light sources.