초록 ▼

An illumination system for a flat panel micro-display device includes a flat panel edge lit lightguide having a polarizing layer on a major surface and a polarization rotator and reflector proximate to an edge face of the lightguide. The polarization rotator changes the polarization state of light t

An illumination system for a flat panel micro-display device includes a flat panel edge lit lightguide having a polarizing layer on a major surface and a polarization rotator and reflector proximate to an edge face of the lightguide. The polarization rotator changes the polarization state of light that is initially reflected from the polarization layer to a desired polarization state from an undesired polarization state and the reflector reflects the light back to the polarization layer. The rotated and reflected light propagating within the lightguide passes though the polarizing layer and illuminates a LCD panel of the micro-display. The combination of the polarization rotator and the reflector provide a controlled system in which most of the initially reflected light is utilized to illuminate the LCD panel. In an embodiment, the polarizing layer is a polarizing film that passes P polarized incoming light and reflects S polarized incoming light, the polarization rotator is a quarter wave plate that rotates light by a quarter wave, and the reflector is a mirror that reflects light without changing the polarization state of the light.

대표청구항 ▼

1. An illumination system for a display device comprising:a lightguide having a first major surface opposite a second major surface and a first edge face opposite a second edge face, said first edge face being positioned to receive light from a light source; a polarizing system proximate to said sec

1. An illumination system for a display device comprising:a lightguide having a first major surface opposite a second major surface and a first edge face opposite a second edge face, said first edge face being positioned to receive light from a light source; a polarizing system proximate to said second major surface which passes a first portion of said light having a desired polarization state to a reflective liquid crystal display panel and which reflects a second portion of said light having an undesired polarization state; and means, integrated with said lightguide, for reflecting said second portion of said light at said second edge face and for rotating the polarization state of said second portion of said light from said undesired polarization state to said desired polarization state, wherein said second portion of said light having said desired polarization state is incident on said polarizing system and is passed to said reflective liquid crystal display panel.