Optical display system and method with optical shifting of pixel position including conversion of pixel layout to form delta to stripe pattern by time base multiplexing

• US 20020075202A1
• Filed: 06/05/2001
• Published: 06/20/2002
• Est. Priority Date: 10/25/1994
• Status: Abandoned Application

• Current Assignee: James L. Fergason
• Original Assignee: James L. Fergason
• Inventors: Fergason, James L.
• Application Number:
  US09/874,820
• Publication Number:
  US 20020075202A1
• Time in Patent Office: Days
• US Class Current: 345/32
• CPC Class Codes: G02B 27/283 used for beam splitting or combining
• CPC Class Codes: G02B 5/3083 Birefringent or phase retarding elements G02B5/3008, G02B5/3016 take precedence; systems for polarisation control G02B27/286; manufacturing phase modulating patterns by lithographic processes G03F7/001
• CPC Class Codes: G02F 1/13363 Birefringent elements, e.g. for optical compensation
• CPC Class Codes: G02F 1/133638 Waveplates, i.e. plates with a retardation value of lambda/n
• CPC Class Codes: G02F 1/1347 Arrangement of liquid crystal layers or cells in which the final condition of one light beam is achieved by the addition of the effects of two or more layers or cells
• CPC Class Codes: G02F 2203/62 Switchable arrangements whereby the element being usually not switchable
• CPC Class Codes: G02F 2413/02 Number of plates being 2
• CPC Class Codes: G02F 2413/04 Number of plates greater than or equal to 4
• CPC Class Codes: G02F 2413/08 with a particular optical axis orientation
• CPC Class Codes: G09G 2310/0235 Field-sequential colour display
• CPC Class Codes: G09G 2310/0237 Switching ON and OFF the backlight within one frame
• CPC Class Codes: G09G 2320/0626 for control of overall brightness
• CPC Class Codes: G09G 2360/144 the light being ambient light
• CPC Class Codes: G09G 2360/16 Calculation or use of calculated indices related to luminance levels in display data
• CPC Class Codes: G09G 3/001 using specific devices not provided for in groups G09G3/02 - G09G3/36, e.g. using an intermediate record carrier such as a film slide; Projection systems; Display of non-alphanumerical information, solely or in combination with alphanumerical information, e.g. digital display on projected diapositive as background slide projectors per se G03B23/00 = 42 HP
• CPC Class Codes: G09G 3/007 Use of pixel shift techniques, e.g. by mechanical shift of the physical pixels or by optical shift of the perceived pixels
• CPC Class Codes: G09G 3/2044 using dithering
• CPC Class Codes: G09G 3/2055 the pattern being varied in time
• CPC Class Codes: G09G 3/3406 Control of illumination source illumination devices structurally associated with liquid crystal cells G02F1/1336
• CPC Class Codes: G09G 3/3648 using an active matrix G09G3/367 - G09G3/3696 take precedence
• CPC Class Codes: H01J 2229/8926 : Active components, e.g. LCD's, indicators, illuminators and moving devices
• CPC Class Codes: H01J 29/89 : Optical or photographic arrangements structurally combined or co-operating with the vessel H01J29/866 and H01J29/868 take precedence
• CPC Class Codes: H04N 13/305 : using lenticular lenses, e.g. arrangements of cylindrical lenses
• CPC Class Codes: H04N 13/31 : using parallax barriers
• CPC Class Codes: H04N 13/324 : Colour aspects
• CPC Class Codes: H04N 13/341 : using temporal multiplexing
• CPC Class Codes: H04N 13/344 : with head-mounted left-right displays
• CPC Class Codes: H04N 13/363 : using image projection screens volumetric display H04N13/388
• CPC Class Codes: H04N 13/395 : with depth sampling, i.e. the volume being constructed from a stack or sequence of 2D image planes
• CPC Class Codes: H04N 13/398 : Synchronisation thereof; Control thereof
• CPC Class Codes: H04N 5/66 : Transforming electric information into light information scanning details H04N3/00
• CPC Class Codes: H04N 5/7441 : the modulator being an array of liquid crystal cells
• CPC Class Codes: H04N 5/7491 : of head mounted projectors
• CPC Class Codes: H04N 9/30 : using solid-state colour display devices
• CPC Class Codes: H04N 9/3102 : using two-dimensional electronic spatial light modulators micromechanical modulators as such G02B26/0833; liquid crystal modulators as such G02F1/13
• CPC Class Codes: H04N 9/3155 : for controlling the light source light source control per se H05B35/00 – H05B47/00; control of an illumination source for displays in general G09G3/3406
• CPC Class Codes: H04N 9/3167 : for polarizing the light beam polarizing optical systems per se G02B27/28
• CPC Class Codes: H04N 9/3173 : wherein the projection device is specially adapted for enhanced portability
• CPC Class Codes: H04N 9/3188 : Scale or resolution adjustment scaling in general G06T3/40; resolution modifying circuits for displays in general G09G5/391

Abstract

An optical display system and method selectively displaces delta triad pixels vertically. The first raster line of picture information is removed from the video signal, and each subsequent raster line of picture information (data) is displaced upward. Next, the entire picture is optically displaced down by a distance equal to one vertical pixel pitch placing the picture back in its original vertical position, but horizontal position of the pixels has changed. Thus picture information is displaced horizontally a distance equal to one and one half times horizontal pixel pitch. Odd pixel rows are displaced in one direction, and even pixel rows are displaced in the opposite direction. The technique can be used to double pixel density and, thus, resolution, in the horizontal direction by the selective shifting technique and coordination with the input video signals. Two views of a picture alternate at the frame rate fast enough to fuse them into a single image, and two successive frames are combined over time to act as a single super frame. This is time based multiplexing of a spatial pattern. Thus, a composite picture is formed using a strip pixel pattern with twice the horizontal pixel density of the original delta pattern. The triads in the first half of this super frame may partially overlap the triads in the second half of the super frame. This technique can be applied to either progressive or interlace scan formats.

Claims

1. A method of displaying an image, comprising:

displaying an unshifted image in a first time interval between a time t₀ and a time t₁;

displaying a first shifted image in a second time interval between the time t₁ and a time t₂, wherein the first shifted image is vertically displaced by one-half of a pixel height relative to the unshifted image;

displaying a second shifted image in a third time interval between the time t₂ and a time t₃, wherein the second shifted image is vertically displaced by the pixel height relative to the unshifted image; and

displaying a third shifted image in a fourth time interval between the time t₃ and a time t₄, wherein the second shifted image is vertically displaced by one and one-half times the pixel height relative to the unshifted image;

wherein the shifted images are shifted by selectively sending signals to a one-pixel-height polarization rotating device and to a one-half-pixel height polarization rotating device, and wherein the polarization rotating devices are calcite crystals.