Lighting system and projector

Abstract

The invention provides a compact, thin, and lightweight lighting system and projector. A lighting system included in a projector according to the present invention is provided with an LED array having LEDs and a reflective plate at the rear side of the LEDs in the light emitting direction, retardation films, a taper rod lens array, a rod lens array, and a reflective polarizing plate.

1 . A lighting system, comprising: 
 at least one light source;    a polarization conversion device that polarizes light from the light source in one direction; and    at least one reflection plate that is disposed at a rear side of the light source in a light emitting direction such that a reflective face of the at least one reflection plate is opposite to the light source;    the polarization conversion device being provided at a light emitting side of the light source, the polarization conversion device having a reflective polarizing plate that transmits polarized light having a predetermined vibration direction and reflects polarized light having vibration directions other than the predetermined vibration direction; and    a retardation film is provided between the light source and the reflective polarizing plate.    
   
   
       2 . The lighting system according to  claim 1 , the retardation film having a nonuniform phase difference.  
   
   
       3 . The lighting system according to  claim 1 , further comprising at least one of a rod and a tubular light guide provided between the light source and the reflective polarizing plate, the tubular light guide having a reflective inner face.  
   
   
       4 . The lighting system according to  claim 1 , the reflective polarizing plate including a grid polarizer having a plurality of reflective elements arranged in a striped pattern at a pitch that is smaller than the wavelength of incident light.  
   
   
       5 . A projector, comprising: 
 the lighting system according to  claim 1 , the lighting system being a planar lighting system including a plurality of the light sources that are arranged in a flat or curved plane and that emit color light beams of different colors in order of time;    a light modulation device including a light valve that is driven in a time division mode in synchronization with emerging timings of color light beams emerging from the light source in order of time; and    a projecting device that projects the light modulated by the light modulation device.    
   
   
       6 . A projector, comprising: 
 a plurality of lighting systems, each of the plurality of lighting systems including the lighting system of  claim 1 , each of the lighting systems being a planar lighting system including a plurality of the light sources that are arranged in a flat plane, the lighting systems emitting color light beams of different colors;    a plurality of light modulation devices including light valves that modulate color light beams emerging from the lighting systems via the polarization devices;    a color combining device that combines the modulated color light from the plurality of light modulation devices; and    a projecting device that projects the light combined by the color combining means.