Projection type image display device

Abstract

A projection type image display device includes a plurality of image display elements that perform modulation of light rays in accordance with an image signal, a color synthesizing optical element for synthesizing light rays having mutually different wavelength ranges that have been modulated by these image display elements by use of a dichroic membrane, lens groups having a positive refractive power as a whole that are disposed between the image display element and the color synthesizing optical element, and a projection optical system for projecting an image synthesized by the color synthesizing optical element. The projection type image display device further includes a storage circuit for storing data used to correct the brightness irregularity of a projected image, and a brightness irregularity correcting circuit for correcting brightness irregularity of a projected image on the basis of the data stored in the storage circuit.

1 - 5 . (canceled)  
   
   
       6 . A projection type image display device comprising: 
 a plurality of image display elements, each of which modulates light rays in accordance with an image signal;    a color synthesizing optical element comprising a dichroic film including a gradient film in which its thickness varies in a predetermined direction, the color synthesizing optical element synthesizing the light rays modulated by the plurality of image display elements;    a projection optical system projecting the light rays synthesized by the color synthesizing optical element onto a projection surface; and    a signal processing circuit which corrects the image signal by one of each pixel and each pixel area such that brightness irregularity in the predetermined direction of an image projected by the projection optical system is reduced or cancelled,    wherein the signal processing circuit corrects the image signal such that the brightness irregularity, which cannot be corrected by the gradient film, is reduced or cancelled.    
   
   
       7 . The projection type image display device according to  claim 6 , wherein the signal processing circuit corrects the image signal such that the brightness irregularity in the predetermined direction which cannot be corrected by the gradient film is cancelled.  
   
   
       8 . The projection type image display device according to  claim 6 , further comprising a positive refractive lens disposed between the image display elements and the color synthesizing optical element, 
 wherein an incident angle onto the dichroic film of the light rays condensed by the positive refractive lens varies in the predetermined direction.    
   
   
       9 . The projection type image display device according to  claim 6 , wherein the dichroic film reflects a first color light and transmits a second light, the first color light being one of red color light, a green color light and a blue color light with different wavelength regions, and the second color light being one of the other two lights that are not reflected.  
   
   
       10 . A projection type image display device comprising: 
 a plurality of image display elements, each of which modulates light rays in accordance with an image signal;    a color synthesizing optical element comprising a dichroic film including a gradient film in which its refractive index varies in a predetermined direction, the color synthesizing optical element synthesizing the light rays modulated by the plurality of image display elements;    a projection optical system projecting the light rays synthesized by the color synthesizing optical element onto a projection surface; and    a signal processing circuit which corrects the image signal by one of each pixel and each pixel area such that brightness irregularity in the predetermined direction of an image projected by the projection optical system is reduced or cancelled, wherein the signal processing circuit corrects the image signal such that the brightness irregularity, which cannot be corrected by the gradient film, is reduced or cancelled.