In this thesis, single-panel sequential-color liquid crystal on silicon (LCOS) projector using LED lamps was presented. This kind of projector can be very small and is an ideal display for mobile devices. Power consumption and optical efficiency are two important criteria of this kind of mobile projectors. A specific electronic subsystem was designed to drive this sequential-color LCOS microdisplay with low power consumption. A secondary optics for the LED lamps was developed to improve the optical efficiency of the projector....[ Read more ]

In this thesis, single-panel sequential-color liquid crystal on silicon (LCOS) projector using LED lamps was presented. This kind of projector can be very small and is an ideal display for mobile devices. Power consumption and optical efficiency are two important criteria of this kind of mobile projectors. A specific electronic subsystem was designed to drive this sequential-color LCOS microdisplay with low power consumption. A secondary optics for the LED lamps was developed to improve the optical efficiency of the projector.

Conventional sequential-color projectors employed red, green, and blue (RGB) color sequential to render color projection. In this thesis, I firstly developed an electronic subsystem to drive the LCOS microdisplay in RGB sequence. I further developed a red, green, blue and white (RGBW) color sequence to render a brighter color projection. The RGBW color sequence running at 240 Hz could improved the optical efficiency by 30%, compared with the color break up observed on the 180 Hz RGB color sequence.

A secondary optics was designed to focus the LED light onto the small LCOS panel. Different secondary optics in the form of compound parabolic concentrators (CPCs) were designed and analyzed. The custom-designed CPC presented the best efficiency up to 80%. Moreover, 35% of light could fall into F#2.0 of the optical system.

A 0.59-inch diagonal LCOS with a resolution of 800x600 pixel, Super Video Graphics Array (SVGA) and 185 lumens (lm) RGB LEDs were used to implement this sequential-color LCOS projector. As for RGB color sequence, a 3 lm projector was obtained. As for RGBW color sequence, a 3.9 lm projector was obtained.