Abstract:
A pixelated image display system comprising: a first panel including an array of pixel elements, each pixel element partially masked by an opaque region; one or more additional panels, each additional panel including an array of pixel elements, each pixel element partially masked by an opaque region; means for directing a different subset of pixel data from an image dataset to each the panel to control the pixel elements of each panel; and means for aligning and projecting interleaved pixel elements, in at least one of the horizontal and vertical directions, from each panel onto a screen to form a pixelated image.

Description:
FIELD OF THE INVENTION 
     The present invention relates to the field of projected pixelated displays; more specifically, it relates to a method and an apparatus for increasing the resolution of projected pixelated images. 
     BACKGROUND OF THE INVENTION 
     In a pixelated display system, light is either, depending upon the type of display panel used by the system, reflected from the display panel or passed through the display panel, directed through an optical system and projected on a screen to form an image. Each display panel includes an array of pixel elements that either selectively reflect the light onto or away from the optical system in the case of a reflected light system, or selectively block or transmit light in the case of a transmissive system. The array elements are controlled based on electronic data created from the original image, the image being broken into equal area pixels, the number of pixels being equal to the number of pixel elements in the display panel. 
     The resolution of a given display panel is limited by the number of discrete pixel elements of the display panel. For example, a “1280 by 1024” display can deliver no more than 1280 pixel elements horizontally and no more than 1024 lines of pixel elements vertically. Ultimately, the number of pixels in a given display panel is limited by the physical size of each pixel element in the display panel. Currently, to increase the resolution of a projected image either the display screen must be in increased in size or the pixel element size must be reduced in order to increase the pixel density. Both these solutions present problems. As the size of display panels increases, size, weight and power consumption become issues as well as manufacturability and cost. Reduction of pixel element size is limited by semiconductor technology and becomes progressively more expensive as pixel size decreases. Further, a higher density of pixels results in less output per pixel and produces a projected image with reduced overall light output and poor contrast. 
     SUMMARY OF THE INVENTION 
     A first aspect of the present invention is a pixelated image display system comprising: a first panel including an array of pixel elements, each pixel element partially masked by an opaque region; one or more additional panels, each additional panel including an array of pixel elements, each pixel element partially masked by an opaque region; means for directing a different subset of pixel data from an image dataset to each panel to control the pixel elements of each panel; and means for aligning and projecting interleaved pixel elements, in at least one of the horizontal and vertical directions, from each panel onto a screen to form a pixelated image. 
     A second aspect of the present invention is a pixelated image display apparatus comprising: a first panel comprising an array of pixel elements and a mask having opaque regions and transparent regions overlaying the array, each pixel element partially masked by a portion of one of the opaque regions of the mask; one or more additional panels, each additional panel comprising an array of pixel elements and a mask having opaque regions and transparent regions overlaying the array, each pixel element partially masked by a portion of one of the opaque regions of the mask; and means to interleave images of each panel and project the resultant interleaved image. 
     A third aspect of the present invention is a method of forming a pixelated image comprising: providing a first panel comprising an array of pixel elements and a mask having opaque regions and transparent regions overlaying the array, each pixel element partially masked by a portion of one of the opaque regions of the mask; providing one or more additional panels, each additional panel comprising an array of pixel elements and a mask having opaque and transparent regions overlaying the array, each pixel element partially masked by a portion of one of the opaque regions of the mask; and projecting an interleaved images of the images formed on each panel. 
    
    
     BRIEF DESCRIPTION OF DRAWINGS 
     The features of the invention are set forth in the appended claims. The invention itself, however, will be best understood by reference to the following detailed description of an illustrative embodiment when read in conjunction with the accompanying drawings, wherein: 
     FIG. 1A is a schematic diagram of a first pixel array according to the present invention; 
     FIG. 1B is a schematic diagram of a first array mask according to the present invention; 
     FIG. 1C is a schematic diagram of a first display panel according to the present invention; 
     FIG. 2A is a schematic diagram of a second pixel array according to the present invention; 
     FIG. 2B is a schematic diagram of a second array mask according to the present invention; 
     FIG. 2C is a schematic diagram of a second display panel according to the present invention; 
     FIG. 3 is a schematic diagram of a projected image according to the present invention; 
     FIG. 4 is a schematic perspective view of a projected display system incorporating display panels in accordance with the present invention; 
     FIG. 5A is a detailed schematic diagram illustrating formation of increased resolution projected pixels according to a first embodiment of the present invention; 
     FIG. 5B is a detailed schematic diagram illustrating formation of increased resolution projected pixels according to a second embodiment of the present invention; 
     FIG. 6A is a detailed schematic diagram illustrating formation of increased resolution projected pixels according to a third embodiment of the present invention; 
     FIG. 6B is a detailed schematic diagram illustrating formation of increased resolution projected pixels according to a fourth embodiment of the present invention; 
     FIG. 7 is a detailed schematic diagram illustrating formation of increased resolution projected pixels according to a fifth embodiment of the present invention; and 
     FIG. 8 is a detailed schematic diagram of single pixel element of a display panel according to a sixth embodiment of the present invention. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     FIGS. 1A-1C,  2 A- 2 C and  3  illustrate the basic principle of the present invention and form the first embodiment of the present invention. 
     FIG. 1A is a schematic diagram of a first pixel array according to the present invention. In FIG. 1A, a first array  100  includes a multiplicity of equally sized pixel elements  105  arranged in rows  110  and columns  115 . First array  100  has a length “L” and a width “W.” There are 2X−1 columns  115  in the “W” or horizontal direction and Y rows  110  in the “L” or vertical direction. Each pixel  105  has a first vertical edge  120  and an opposite second vertical edge  125 . Columns  115  are numbered sequentially by odd integers in the “W” direction and rows  110  are numbered sequentially by integers in the “L” direction. First array  100  may be a transmissive array such as a transmissive liquid crystal display (TLCD) or a reflective array such as a deformable mirror device (DMD), liquid crystal on silicon (LCOS) device or a reflective liquid crystal display (RLCD). 
     FIG. 1B is a schematic diagram of a first array mask according to the present invention. In FIG. 1B, a first mask  130  includes a multiplicity of opaque regions  135 , equally spaced apart and interspersed by transparent regions  140 . First mask  130  also has a length “L” and a width “W.” Both opaque regions  135  and transparent regions  140  extend in the “L” direction and in the present example, form a vertical stripe pattern starting with a transparent region  140 . Each opaque region  135  has a first vertical edge  145  and an opposite second vertical edge  150 . One transparent region  140  and an adjacent opaque region  135  form a transparent/opaque region pair  155 . Each transparent/opaque region pair  155  is the same width as each column  115 . 
     FIG. 1C is a schematic diagram of a first display panel according to the present invention. In FIG. 1C, first mask  130  of FIG. 1B is overlaid on first array  100  of FIG. 1A to form a first panel  160 . First panel  160  also has a length “L” and a width “W.” Each opaque region  135  of first mask  130  covers a portion of each column  115  of first array  100 , the second vertical edge  150  of each opaque region  135  being aligned to the second vertical edge  125  of the pixel elements  105  in column  115  so as to expose only a portion of each pixel  105  though transparent regions  140 . 
     FIG. 2A is a schematic diagram of a second pixel array according to the present invention. In FIG. 2A, a second array  200  includes a multiplicity of equally pixel elements  205  arranged in rows  210  and columns  215 . The size of pixel elements  205  is the same as the size of pixel elements  105  of FIG.  1 A. First array  200  also has a length “L” and a width “W.” There are 2X columns  215  in the “W” or horizontal direction and Y rows  210  in the “L” or vertical direction. Each pixel  205  has a first vertical edge  220  and an opposite second vertical edge  225 . Columns  215  are numbered sequentially by even integers in the “W” direction and rows  210  are numbered sequentially by integers in the “L” direction. Second array  200  may be a transmissive array such as a transmissive liquid crystal display (TLCD) or a reflective array such as a deformable mirror device (DMD), liquid crystal on silicon (LCOS) device or a reflective liquid crystal display (RLCD). 
     FIG. 2B is a schematic diagram of a second array mask according to the present invention. In FIG. 2B, a second mask  230  includes a multiplicity of opaque regions  235 , equally spaced apart and interspersed by transparent regions  240 . First mask  230  also has a length “L” and a width “W.” Both opaque regions  235  and transparent regions  240  extend in the “L” direction and in the present example, form a vertical stripe pattern starting with an opaque region  235 . Each opaque region  235  has a first vertical edge  245  and an opposite second vertical edge  250 . One opaque region  235  and an adjacent transparent region  240  form an opaque/transparent region pair  255 . Each opaque/transparent region pair  255  is the same width as each column  215 . 
     FIG. 2C is a schematic diagram of a second display panel according to the present invention. In FIG. 2C, second mask  230  of FIG. 2B is overlaid on second array  200  of FIG. 2A to form a second panel  260 . Second panel  260  also has a length “L” and a width “W.” Each opaque region  235  of second mask  230  covers a portion of each column  215  of second array  200 , the first vertical edge  245  of each opaque region  235  being aligned to the second vertical edge  225  of the pixel elements  205  in the column  215  below so as to expose only a portion of each pixel  205  though transparent regions  240 . 
     FIG. 3 is a schematic diagram of a projected image according to the present invention. First and second panels  160  and  260  of FIGS. 1C and 2C respectively, are used in a projection system, an example of which is illustrated in FIG.  4  and described infra, to produce an interleaved image  300 . In FIG. 3, interleaved image  300  includes a multiplicity of equally sized pixels  305  arranged in rows  310  and columns  315 . Interleaved image  300  has a length “ML” and a width “MW,” where M is a magnification factor applied to “L” and “W” that may be less than, equal to, or greater than one. There are 2X columns  315  in the “MW” or horizontal direction and Y rows  310  in the “ML” or vertical direction. Pixels in odd number columns  315  have been projected from first panel  160  (see FIG. 1C) and pixels in even number columns have been projected from second panel  260  (see FIG.  2 C). 
     Interleaved image  300  has twice as many pixels in the horizontal direction has would have been obtained by projecting either first panel  160  alone or second panel  260  alone. The total brightness of each pixel  305  is half that of pixels that would be formed by projecting either pixel elements  105  alone (see FIG. 1A) or pixel elements  205  alone (see FIG.  2 A), but since there are twice as many pixels  305 , the brightness of interleaved image  300  is the same as would have been obtained by projecting either first panel  160  alone or second panel  260  alone. 
     FIG. 4 is a schematic perspective view of a projected display system incorporating display panels in accordance with the present invention. In FIG. 4, display system  400  includes an image dataset  405 , electronics  410 , first and second light sources  415  and  420 , optionally first and second color wheels  425  and  430 , first and second panels  160  and  260  and first and second lenses  435  and  440  producing interleaved image  300  on screen  445 . 
     In the present example, image dataset  405  contains a single pixelated frame (for a still picture) or a series of pixelated frames (for a video picture) having Y vertical and 2X horizontal pixels per frame. Each frame of data is split by electronics  410  into an odd data stream  450  containing only the odd columns of pixels and an even data stream  454  containing only the even columns of pixels. Odd data stream  450  controls pixel elements  105  in first panel  160  and even data stream  455  controls pixel elements  205  in second panel  260 . 
     Light from first light source  415 , shining on first panel  160  is reflected by first panel  160  and focused by first lens  435  on screen  445  to produce a first portion of interleaved image  300 . Light from second light source  420 , shining on second panel  260  is reflected by second panel  260  and focused by second lens  440  on screen  445  to produce the second half of interleaved image  300 . The half images are interleaved as illustrated in FIG.  3  and described supra, to produce a complete frame. 
     Optional first and second color wheels  425  and  430  may be used to produce color images from a dataset having three sets of data (red, blue and green) sequentially sent to first and second panels  160  and  260  by electronics  410 . Alternatively, color may be obtained by using six panels in pairs of first panels  160  and second panels  260 , sending appropriate data streams to each panel, and optically focusing the light reflected by each panel onto screen  445 . 
     A transmitted light system may be substituted when first and second panels are transmissive rather than reflective by positioning the light sources behind the panels so that the light is blocked by opaque pixel elements and light passing through transparent pixel elements is then focused on the screen. The present embodiment may be applied to the vertical direction instead of the horizontal, as one skilled in the art will recognize. 
     FIG. 5A is a detailed schematic diagram illustrating formation of increased resolution projected pixels according to the first embodiment of the present invention. In FIG. 5A, on first panel  160  (see FIG.  1 C), pixel element  105  is partially masked by opaque region  135  and exposed through transparent region  140  of first mask  130  (see FIG.  1 B). Transparent region  140  and opaque region  135  meet along virtual reference line  165 . Pixel element  105  has a width “W1” and a width “W2” of pixel element  105  is exposed. “W2”=“W1”/2. 
     On second panel  260  (see FIG.  2 C), pixel element  205  is partially masked by opaque region  235  and exposed through transparent region  240  of second mask  230  (see FIG.  2 B). Transparent region  240  and opaque region  235  meet along virtual reference line  265 . Pixel element  205  also has a width “W1” and a width “W2” of pixel element  205  is exposed. “W2”=“W1”/2 
     Pixel element  105  is projected to form pixel  305 A and pixel element  205  is projected to form pixel  305 B, the projection is done in a manner to superimpose virtual reference line  165  over virtual reference line  265  to produce virtual reference line  365 . 
     The first embodiment of the present invention may be applied to the vertical direction instead of the horizontal, as one skilled in the art will recognize. 
     FIG. 5B is a detailed schematic diagram illustrating formation of increased resolution projected pixels according to a second embodiment of the present invention. In FIG. 5B, on first panel  160  (see FIG.  1 C), pixel element  105  is partially masked by opaque region  135  and exposed through transparent region  140 . Opaque region  135  and transparent region  140  are separated by a transition region  170  centered on virtual reference line  165 . Transition region  170  is graded from opaque (optical density of opaque region  135 ) to transparent (optical density of transparent region  140 ) in the “A” direction. The optical density of transition region  170  along virtual reference line  165  is half of the sum of the optical density of opaque region  135  and the optical density of transparent region  140 . Transparent region  140  and opaque region  135  are equally spaced from virtual reference line  165 . 
     A second transition region  172 A is located along an edge  174 A of transparent region  140  and is half as wide as transition region  170 . Transition region  172 A is graded from transparent (optical density of transparent region  140 ) an optical density equal to half of the sum of the optical density of opaque region  135  and the optical density of transparent region  140  in the “B” direction. 
     A third transition region  172 B is located along an edge  174 B of opaque region  135  and is half as wide as transition region  170 . Transition region  172 B is graded from opaque (optical density of opaque region  135 ) to an optical density equal to half of the sum of the optical density of opaque region  135  and the optical density of transparent region  140  in the “C” direction. 
     Transition regions  170 ,  172 A and  172 B and all subsequently described transition regions are fabricated as part of the corresponding mask along with the opaque regions or alternatively may be fabricated on a second mask applied to the array. Pixel element  105  has a width “W1” and a width “W3” of pixel element  105  is exposed. Transition region  170  has a width “W4.” “W4” maybe between about 0 to 20% of “W1.” “W2”=(“W3”+“W4”/2)=“W1”/2. 
     On second panel  260  (see FIG.  2 C), pixel element  205  is partially masked by opaque region  235  and exposed through transparent region. Opaque region  235  and transparent region  240  are separated by a transition region  270  centered on virtual reference line  265 . Transition region  270  is graded from opaque (optical density of opaque region  235 ) to transparent (optical density of transparent region  240 ) in the “D” direction. The optical density of transition region  270  along virtual reference line  265  is half of the sum of the optical density of opaque region  235  and the optical density of transparent region  240 . Transparent region  240  and opaque region  235  are equally spaced from virtual reference line  265 . 
     A second transition region  272 A is located along an edge  274 A of transparent region  240  and is half as wide as transition region  270 . Transition region  272 A is graded from transparent (optical density of transparent region  240 ) an optical density equal to half of the sum of the optical density of opaque region  235  and the optical density of transparent region  240  in the “E” direction. 
     A third transition region  272 B is located along an edge  274 B of opaque region  235  and is half as wide as transition region  270 . Transition region  272 B is graded from opaque (optical density of opaque region  235 ) to an optical density equal to half of the sum of the optical density of opaque region  235  and the optical density of transparent region  240  in the “F” direction. 
     Transition region  270  has a width “W4.” “W4” may be between about 0 to 20% of “W1.” The “B” direction is the opposite direction from the “A” direction. “W2”=(“W3”+“W4”/2)=“W1”/2. 
     Pixel element  105  is projected to form pixel  305 A and pixel element  205  is projected to form pixel  305 B, the projection is done in a manner to superimpose virtual reference line  165  over virtual reference line  265  to produce virtual reference line  365 . Pixel  305 A overlaps pixel  305 B in overlap regions  320 ,  322 A and  322 B. The overlap region minimizes frame distortion caused by misalignment of the optical projection system. 
     The second embodiment of the present invention may be applied to the vertical direction instead of the horizontal, as one skilled in the art will recognize. 
     The third and fourth embodiments of the present invention address the situation where pixel elements contain non-reflective or non-transmissive mechanical support or circuit substructures. 
     FIG. 6A is a detailed schematic diagram illustrating formation of increased resolution projected pixels according to a third embodiment of the present invention. In FIG. 6A, on first panel  160  (see FIG.  1 C), pixel element  105  is partially masked by first and second opaque regions  135 A and  135 B and exposed through transparent region  140 . Transparent region  140  straddles virtual reference line  165  and is located between first and second opaque regions  135 A and  135 B. An edge  175 A of first opaque region  135 A is aligned with a first edge  180 A of pixel element  105  and an edge  175 B of second opaque region  135 B is aligned with a second and opposite edge  180 B of pixel element  135 B. Pixel element  105  has a width “W1” and a width “W2” of pixel element  105  is exposed. “W2”=“W1”/2. In the present example, a substructure  185  of pixel element  105  is masked by opaque region  135 A. 
     On second panel  260  (see FIG.  2 C), pixel element  205  is partially masked by opaque region  235  and exposed through transparent region  240 . Transparent region  240  straddles virtual reference line  265  and is located between first and second opaque regions  235 A and  235 B. An edge  275 A of first opaque region  235 A is aligned with a first edge  280 A of pixel element  205  and an edge  275 B of second opaque region  235 B is aligned with a second and opposite edge  280 B of pixel element  205 . Pixel element  205  also has a width “W1” and a width “W2” of pixel element  205  is exposed. “W2”=“W1”/2. In the present example, a substructure  285  of pixel element  205  is masked by opaque region  235 A. 
     Pixel element  105  is projected to form pixel  305 A and pixel element  205  is projected to form pixel  305 B, the projection is done in a manner such that transparent pixels  305 A and  305 B abut along a virtual reference line  365 . Virtual reference line  165  is positioned by optical-mechanical means to be midway between virtual reference line  365  and an outer edge  370 A of pixel  305 A and virtual reference line  265  is positioned by optical-mechanical means to be midway between virtual reference line  365  and an outer edge  370 B of pixel  305 B. 
     The third embodiment of the present invention may be applied to the vertical direction instead of the horizontal, as one skilled in the art will recognize. 
     FIG. 6B is a detailed schematic diagram illustrating formation of increased resolution projected pixels according to a fourth embodiment of the present invention. In FIG. 6B, on first panel  160  (see FIG.  1 C), pixel element  105  is partially masked by first and second opaque-regions  135 A and  135 B and exposed through transparent region  140 . Transparent region  140  straddles virtual reference line  165  and is located between first and second opaque regions  135 A and  135 B. An edge  175 A of first opaque region  135 A is aligned with a first edge  180 A of pixel element  105 . An edge  175 B of second opaque region  135 B is aligned with a second and opposite edge  180 B of pixel element  135 B. First and second opaque region  135 A and  135 B are separated from transparent region  140  by first and second transition regions  170 A and  170 B respectively. First and second transition regions  170 A and  170 B are graded from opaque (optical density of opaque regions  135 A and  135 B) to transparent (optical density of transparent region  140 ) in the “A” direction. The optical density of first and second transition regions  170 A and  170 B along virtual reference lines  190 A and  190 B respectively is half of the sum of the optical density of first and second opaque region  135 A and  135 B and the optical density of transparent region  140 . Transparent region  140  and opaque region  135  are equally spaced from virtual reference line  165 . Pixel element  105  has a width “W1” and a width “W3” of pixel element  105  is exposed. Transition regions  170 A and  170 B each have a width “W4.” “W4” may be between about 0 to 20% of “W1.” “W2”=(“W3”+“W4”/2)=“W1”/2. In the present example, a substructure  185  of pixel element  105  is masked by opaque region  135 A. 
     On second panel  260  (see FIG.  2 C), pixel element  205  is partially masked by first and second opaque regions  235 A and  235 B and exposed through transparent region  240 . Transparent region  240  straddles virtual reference line  265  and is located between first and second opaque regions  235 A and  235 B. An edge  275 A of first opaque region  235 A is aligned with a first edge  280 A of pixel element  205 . An edge  275 B of second opaque region  235 B is aligned with a second and opposite edge  280 B of pixel element  205 . First and second opaque region  235 A and  235 B are separated from transparent region  240  by first and second transition regions  270 A and  270 B respectively. First and second transition regions  270 A and  270 B are graded from opaque (optical density of opaque regions  235 A and  235 B) to transparent (optical density of transparent region  240 ) in the “A” direction. The optical density of first and second transition regions  270 A and  270 B along virtual reference lines  290 A and  190 B respectively is half of the sum of the optical density of first and second opaque region  235 A and  235 B and the optical density of transparent region  240 . Transparent region  240  and opaque region  235  are equally spaced from virtual reference line  265 . Pixel element  205  has a width “W1” and a width “W3” of pixel element  205  is exposed. Transition regions  270 A and  270 B each have a width “W4.” “W4” may be between about 0 to 20% of “W1.” “W2”=(“W3”+“W4”/2)=“W1”/2. In the present example, a substructure  285  of pixel element  205  is masked by opaque region  235 A. 
     Pixel element  105  is projected to form pixel  305 A and pixel element  205  is projected to form pixel  305 B, the projection is done in a manner such that transparent pixels  305 A and  305 B abut along a virtual reference line  365 . Virtual reference line  165  is positioned by optical-mechanical means to be midway between virtual reference line  365  and an outer edge  370 A of pixel  305 A and virtual reference line  265  is positioned by optical-mechanical means to be midway between virtual reference line  365  and an outer edge  370 B of pixel  305 B. Pixel  305 A overlaps pixel  305 B in overlap region  320 . The overlap region minimizes frame distortion caused by misalignment of the optical projection system. 
     The fourth embodiment of the present invention may be applied to the vertical direction instead of the horizontal, as one skilled in the art will recognize. 
     FIG. 7 is a detailed schematic diagram illustrating formation of increased resolution projected pixels according to a fifth embodiment of the present invention. In FIG. 7, a first pixel element  500 A on a first panel (not shown) is partially masked by an opaque region  505 A and exposed through a transparent region  510 A. In the present example, clear region  510 A occupies the upper left quadrant of pixel element  500 A and opaque region  505 A occupies the remaining three quadrants. First pixel element  500 A is designated  1 - 1  for first row, first column of the projected image described infra. 
     A second pixel element  500 B on a second panel (not shown) is partially masked by an opaque region  505 B and exposed through a transparent region  510 B. In the present example, clear region  510 B occupies the lower left quadrant of pixel element  500 B and opaque region  505 B occupies the remaining three quadrants. Second pixel element  500 B is designated  1 - 2  for first row, second column of the projected image described infra. 
     A third pixel element  500 C on a third panel (not shown) is partially masked by an opaque region  505 C and exposed through a transparent region  510 C. In the present example, clear region  510 C occupies the upper right quadrant of pixel element  500 C and opaque region  505 C occupies the remaining three quadrants. Third pixel element  500 C is designated  2 - 1  for second row, first column of the projected image described infra. 
     A fourth pixel element  500 D on a fourth panel (not shown) is partially masked by an opaque region  505 D and exposed through a transparent region  510 D. In the present example, clear region  510 D occupies the lower right quadrant of pixel element  500 D and opaque region  505 D occupies the remaining three quadrants. Fourth pixel element  500 D is designated  2 - 2  for second row, second column of the projected image described infra. 
     Pixel elements  500 A,  500 B,  500 C and  500 D have a width “W1” and a length “L1.” Transparent regions  510 A,  510 B,  510 C and  510 D have a width “W2” and a length “L2.” “W2”=“W1”/2 and “L2”=“L1”/2. 
     Light reflected off (or transmitted through) pixel elements  510 A,  510 B,  510 C and  510 D are projected to form pixels  515 A,  515 B,  515 C and  515 D of projected image  520 . Thus, the resolution has been doubled in both the horizontal and vertical directions of interleaved image  520 . 
     FIG. 8 is a detailed schematic diagram of single pixel element of a display panel according to a sixth embodiment of the present invention. In the sixth embodiment a transition region is applied to each pixel element of the fifth embodiment, however only pixel element  500 A is illustrated. Pixel elements  500 B,  500 C and  500 D are treated similarly to pixel element  500 A. In FIG. 8, a transition region  525 A is located between adjacent edges  530 A and  535 A of clear region  510 A and respective opposing adjacent edges  540 A and  545 A of opaque region  505 A. Transparent region  510 A has a width of “W3” and a length of “L3.” Transition region  525 A has a width “W4.” “W4” may be between about 0 to 20% of “W1. “W2”=(“W3”+“W4”/2)=“W1”/2. “L2”=(“L3”+“L4”/2)=“L1”/2. 
     The description of the embodiments of the present invention is given above for the understanding of the present invention. It will be understood that the invention is not limited to the particular embodiments described herein, but is capable of various modifications, rearrangements and substitutions as will now become apparent to those skilled in the art without departing from the scope of the invention. Therefore, it is intended that the following claims cover all such modifications and changes as fall within the true spirit and scope of the invention.