Dual polarization optical projection systems and methods

Abstract

A dual polarization optical projection system and method combines images from first and second image sources. The first image source includes a first array of image pixels wherein the first image source generates a first pixel image having a first polarization. The second image source includes a second array of image pixels wherein the second image source generates a second pixel image having a second polarization orthogonal to the first polarization. The first pixel image having the first polarization is combined with the second pixel image having the second polarization to form a combined pixel image. Each pixel of the combined pixel image corresponds to a combination of a first pixel from the first array of image pixels having the first polarization and a second pixel from the second array of image pixels having the second polarization.

That which is claimed:  
     
         1 . A dual polarization optical projection system, comprising: 
 a first image source comprising a first array of image pixels wherein said first image source generates a first pixel image having a first polarization;    a second image source comprising a second array of image pixels wherein said second image source generates a second pixel image having a second polarization orthogonal to said first polarization; and    combining means for combining said first pixel image having said first polarization with said second pixel image having said second polarization to form a combined pixel image, such that each pixel of said combined pixel image corresponds to a combination of a first pixel from said first array of image pixels having said first polarization and a second pixel from said second array of image pixels having said second polarization.    
     
     
         2 . A dual polarization optical projection system according to    claim 1    wherein said first and second pixel images comprise the same image so that the combined pixel image has an increased intensity.  
     
     
         3 . A dual polarization optical projection system according to    claim 1    wherein said first and second pixel images comprise different images so that the combined pixel image is a three-dimensional image.  
     
     
         4 . A dual polarization optical projection system according to    claim 1    wherein said first and second pixel images comprise the same image, offset from one another by a sub-pixel, so that the combined pixel image is of higher resolution than said first and second pixel images.  
     
     
         5 . A dual polarization optical projection system according to    claim 1    wherein each of said first and second image sources comprises a respective reflective liquid crystal display.  
     
     
         6 . A dual polarization optical projection system according to    claim 1    wherein each of said first and second image sources comprises a respective transmissive liquid crystal display.  
     
     
         7 . A dual polarization optical projection system according to    claim 1    wherein each of said first and second image sources comprises a respective liquid crystal layer and an image generator for generating an image on said liquid crystal layer.  
     
     
         8 . A dual polarization optical projection system according to    claim 1    further comprising: 
 constant angular separation hemispherical projecting means, for projecting said combined pixel image into a hemispherical projection having constant angular separation among adjacent pixels, such that said dual polarization optical projection system projects said combined pixel image onto hemispherical surfaces of varying radii without requiring spatial distortion correction of said first and second arrays of image pixels.  
 
     
     
         9 . A dual polarization optical projection system according to    claim 8    further comprising: 
 a dome including a truncated spherical inner dome surface, said constant angular separation hemispherical projecting means being mounted at the center of said dome to radially project said combined pixel image onto said inner dome surface.  
 
     
     
         10 . A dual polarization optical projection system according to    claim 1    further comprising: 
 means for projecting said combined pixel image from said combining means onto a hemispherical surface at a projection angle of at least 160 degrees; and  
 means for tilting at least part of said projecting means, such that said projecting means projects said combined pixel image in one of a plurality of selectable positions.  
 
     
     
         11 . A dual polarization optical projection system according to    claim 1    wherein each of said first and second pixel images has a common image size, said projection system further comprising: 
 a projection lens assembly which projects said combined pixel image onto a hemispherical surface at a projection angle of at least 160 degrees, said lens assembly being spaced apart from said first and second image sources by a separation distance which is at least six times said image size.  
 
     
     
         12 . A dual polarization optical projection system according to    claim 1    further comprising: 
 a first filter adjacent said first image source, said first filter comprising a first color portion adjacent a first pixel of said first image source which selectively passes a first color of light, and a second color portion adjacent a second pixel of said first image source which selectively passes a second color of light; and  
 a second filter adjacent said second image source, said second filter comprising a first color portion adjacent a first pixel of said second image source which selectively passes said first color of light, and a second color portion adjacent a second pixel of said second image source which selectively passes said second color of light so that said combined pixel image includes said first and second colors.  
 
     
     
         13 . A dual polarization optical projection system according to    claim 1    further comprising: 
 a multi-color light source which provides light having a first color to said first and second image sources during a first predetermined time period and which provides light having a second color to said first and second image sources during a second predetermined time period so that said combined pixel image includes said first color during said first predetermined time period and includes said second color during said second predetermined time period.  
 
     
     
         14 . A dual polarization optical projection system according to    claim 1    further comprising: 
 a single color light source which provides light having a single color to said first and second image sources.  
 
     
     
         15 . A dual polarization projection system comprising: 
 a source of light which projects a first polarized light having a first polarization along a first light path, and which projects a second polarized light having a second polarization orthogonal to said first polarization along a second light path;    a first image source including a first array of image pixels in said first light path which selectively rotates a polarization vector of said first polarized light in response to an intensity of the image pixels;    a second image source including a second array of image pixels in said second light path which selectively rotates a polarization vector of said second polarized light in response to an intensity of the image pixels;    first polarizing filter means in said first light path, downstream of said first image source, for attenuating light from said first light path as a function of polarization;    second polarizing filter means in said second light path, downstream of said second image source, for attenuating light from said second light path as a function of polarization; and    combining means for combining light from said first and second attenuated light paths into a combined light path.    
     
     
         16 . A dual polarization projection system according to    claim 15    wherein said source of polarized light includes; 
 a high intensity source of randomly polarized light; and  
 a polarizing beam splitter which projects said first polarized light having said first polarization along said first light path to said first image source, and which projects said second polarized light having said second polarization along said second light path to said second image source.  
 
     
     
         17 . A dual polarization projection system according to    claim 15    further comprising: 
 a lens assembly in said combined light path downstream of said combining means which projects light from said combined light path onto a hemispherical surface at a projection angle of at least 160 degrees.  
 
     
     
         18 . A dual polarization projection system according to    claim 17    wherein said lens assembly comprises: 
 a collimating lens assembly in said combined light path downstream of said combiner; and  
 a meniscus lens assembly in said combined light path downstream of said collimating lens assembly, to project the collimated light into an angular projection of at least 160 degrees.  
 
     
     
         19 . A dual polarization projection system according to    claim 18    wherein said collimating lens assembly comprises at least three lenses arranged along said optical path, each of said lenses including an index of refraction and a dispersion, each of the three lenses having a common ratio of index of refraction to dispersion.  
     
     
         20 . A dual polarization projection system, according to    claim 17    wherein said lens assembly projects said combined array of image pixels into a hemispherical projection having constant angular separation among adjacent pixels, such that said hemispherical optical projection system projects said array of pixels onto hemispherical surfaces of varying radii without requiring spatial distortion correction of said array of image pixels.  
     
     
         21 . A dual polarization optical projection system according to    claim 15    wherein said first and second image sources each comprise a respective reflective liquid crystal display.  
     
     
         22 . A dual polarization optical projection system according to    claim 15    wherein said first and second image sources each comprise a respective transmissive liquid crystal display.  
     
     
         23 . A dual polarization optical projection system according to    claim 15    wherein said first and second image sources each comprise a respective liquid crystal layer and-image generator for generating an image on said liquid crystal layer.  
     
     
         24 . A dual polarization optical projection system according to    claim 15    further comprising: 
 a dome including a truncated spherical inner dome surface, and a lens assembly mounted at the center of said dome to radially project said combined array of pixels onto said inner dome surface.  
 
     
     
         25 . A dual polarization optical projection system according to    claim 24    further comprising: 
 means for tilting at least part of said lens assembly, such that said optical projection system projects said combined array of pixels onto a plurality of selectable positions on said inner dome surface.  
 
     
     
         26 . A dual polarization optical projection system according to    claim 24    wherein each of said arrays of image pixels has an image size, and wherein said lens assembly is spaced apart from each of said image sources by a separation distance which is at least six times said image size.  
     
     
         27 . A dual polarization optical projection system according to    claim 15    further comprising: 
 a first filter adjacent said first image source, said first filter comprising a first color portion adjacent a first pixel of said first image source which selectively passes a first color of light, and a second color portion adjacent a second pixel of said first image source which selectively passes a second color of light; and  
 a second filter adjacent said second image source, said second filter comprising a first color portion adjacent a first pixel of said second image source which selectively passes said first color of light, and a second color portion adjacent a second pixel of said second image source which selectively passes said second color of light so that said combined pixel image includes said first and second colors.  
 
     
     
         28 . A dual polarization optical projection system according to    claim 15    further comprising: 
 a multi-color light source which provides light having a first color to said first and second image sources during a first predetermined time period and which provides light having a second color to said first and second image sources during a second predetermined time period so that said combined pixel image includes said first color during said first predetermined time period and includes said second color during said second predetermined time period.  
 
     
     
         29 . A dual polarization optical projection system according to    claim 15    further comprising: 
 a single color light source which provides light having a single color to said first and second image sources.  
 
     
     
         30 . A dual polarization optical projection method, comprising the steps of: 
 generating a first pixel image having a first polarization;    generating a second pixel image having a second polarization orthogonal to said first polarization; and    combining said first pixel image having said first polarization with said second pixel image having said second polarization to form a combined pixel image, such that each pixel of said combined pixel image corresponds to a combination of a first pixel from said first pixel image having said first polarization and a corresponding second pixel from said second pixel image having said second polarization.    
     
     
         31 . A dual polarization optical projection method according to    claim 30    wherein said first and second pixel images comprise the same image so that the combined pixel image has an increased intensity.  
     
     
         32 . A dual polarization optical projection method according to    claim 30    wherein said first and second pixel images comprise different images so that the combined pixel image is a three-dimensional image.  
     
     
         33 . A dual polarization optical projection method according to    claim 30    wherein said first and second pixel image comprise the same image, offset from one another by a sub-pixel, so that the combined pixel image is of higher resolution than said first and second pixel images.  
     
     
         34 . A dual polarization optical projection method according to    claim 30    further comprising the step of: 
 projecting said combined pixel image into a hemispherical projection having constant angular separation among adjacent pixels, such that said dual polarization optical projection method projects said combined pixel image onto hemispherical surfaces of varying radii without requiring spatial distortion correction of said first and second pixel images.  
 
     
     
         35 . A dual polarization optical projection method according to    claim 30    further comprising the steps of: 
 projecting said combined pixel image onto a hemispherical surface at a projection angle of at least 160 degrees; and  
 tilting said combined pixel image in one of a plurality of selectable positions.  
 
     
     
         36 . A dual polarization projection method comprising tile steps of: 
 projecting a first polarized light having a first polarization along a first light path; and    projecting a second polarized light having a second polarization orthogonal to said first polarization along a second light path;    selectively rotating a polarization vector of said first polarized light in response to an intensity of a first array of image pixels;    selectively rotating a polarization vector of said second polarized light in response to an intensity of a second array of image pixels;    attenuating light from said first light path as a function of polarization;    attenuating light from said second light path as a function of polarization; and    combining light from said first and second attenuated light paths into a combined light path.    
     
     
         37 . A dual polarization projection method according to    claim 36    further comprising the step of: 
 projecting light from said combined light path onto a hemispherical surface at a projection angle of at least 160 degrees.  
 
     
     
         38 . A dual polarization projection method, according to    claim 36    further comprising the step of: 
 projecting said combined array of image pixels into a hemispherical projection having constant angular separation among adjacent pixels, to project said array of pixels onto hemispherical surfaces of varying radii without requiring spatial distortion correction of said array of image pixels.  
 
     
     
         39 . A dual polarization optical projection method according to    claim 36    further comprising the step of: 
 tilting at least part of said combined light path onto a plurality of selectable positions on said inner dome surface.