Liquid crystal panel and viewfinder for video camera and projection display using liquid crystal panel

• US 5,469,278 A
• Filed: 11/18/1994
• Issued: 11/21/1995
• Est. Priority Date: 09/25/1992
• Status: Expired due to Fees

• Current Assignee: Matsushita Electric Industrial Company Limited (Panasonic Holdings Corporation)
• Original Assignee: Matsushita Electric Industrial Company Limited (Panasonic Holdings Corporation)
• Inventors: Takahara, Hiroshi, Ohmae, Hideki
• Primary Examiner(s): Sikes, William L.
• Assistant Examiner(s): MAI, HUY KIM
• Application Number:
  US08/345,364
• Time in Patent Office: 368 Days
• Field of Search: 359/59, 359/40, 359/41, 359/51, 359/54, 359/68, 359/67, 359/71, 358/60, 353/82, 354/100, 354/102
• US Class Current: 349/86
• CPC Class Codes: G02F 1/1334 based on polymer dispersed liquid crystals, e.g. microencapsulated liquid crystals
• CPC Class Codes: G02F 1/133512 Light shielding layers, e.g. black matrix G02F1/136209 takes precedence
• CPC Class Codes: G02F 1/133514 Colour filters
• CPC Class Codes: G02F 1/1362 Active matrix addressed cells G02F1/134336, G02F1/134363 take precedence
• CPC Class Codes: G02F 1/13756 the liquid crystal selectively assuming a light-scattering state G02F1/1334, G02F1/13718 take precedence
• CPC Class Codes: H04N 23/63 by using electronic viewfinders
• CPC Class Codes: H04N 9/3105 for displaying all colours simultaneously, e.g. by using two or more electronic spatial light modulators simultaneous projection in colour photography G03B33/10; beam splitting or combining systems per se G02B27/10
• CPC Class Codes: H04N 9/312 Driving therefor driving of electronic spatial light modulators in displays other than projection devices G09G3/34, G09G3/36; control of liquid crystal elements G02F1/133; control of micromechanical modulators G02B26/08
• 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 9/317 Convergence or focusing systems electronic adjustment of convergence H04N9/3185; convergence or focusing arrangements for cathode ray tubes H04N9/28; means for automatic focusing of projectors not peculiar to the presence of an electronic spatial light modulator G03B21/53

Abstract

A liquid crystal panel includes a liquid crystal/polymer composite between two substrates, one of which having a matrix of pixel electrodes. A mosaic color filter of red, green and blue is provided above counterelectrodes or pixel electrodes. The average pore size of the resin component or of the diameter of liquid crystal droplets in the composite is selected according to the color of the color filter. The average of pore sizes is the largest for red, and the smallest for blue. The average of pore sizes of the resin on the switching elements and on the signal lines is smaller than that on the pixel electrodes. This liquid crystal display panel is used as a light bulb for a projection type television system. This liquid crystal display panel is also used as a viewfinder of a video camera.

Claims

1. A liquid crystal panel comprising:

a first substrate having pixel electrodes arranged as a matrix;

a second substrate having a counterelectrode; and

a liquid crystal/polymer composite consisting of a liquid crystal component and a polymer component, said composite being interposed between said first and second electrode substrates, and said composite comprising of a first region and a second region defined on each of said pixel electrodes, an average pore size of said polymer component in said first region being different from that of said second region.

2. The liquid crystal panel according to claim 1, wherein said polymer component included in said liquid crystal/polymer composite comprises an ultra-violet ray setting resin.

3. The liquid crystal panel according to claim 1, further comprising:

switching elements formed on said first substrate each arranged for a pixel electrode and signal lines for applying signals to the switching elements and the pixel electrodes; and

shading films applied to said switching elements.

4. The liquid crystal panel according to claim 3, said liquid crystal/polymer composite further comprising third regions defined between said pixel electrodes, wherein an average pore size in said first and second regions is larger than that in said third regions.

5. The liquid crystal panel according to claim 1, said liquid crystal/polymer composite further comprising third regions defined between said pixel electrodes, wherein an average pore size in said first and second regions is larger than that in said third regions.

6. A liquid crystal panel comprising:

a first substrate having pixel electrodes arranged as a matrix;

a second substrate having a counterelectrode; and

a liquid crystal/polymer composite consisting of a liquid crystal component and a polymer component;

said composite being interposed between said first and second electrode substrates, and said composite comprising first regions defined on said pixel electrodes and second regions defined between said pixel electrodes, an average pore size in said first regions being larger than that in said second regions.

7. The liquid crystal panel according to claim 6, further comprising a color filter provided above said first or second substrate, wherein said color filter has red regions, green regions, and blue regions, each of said regions being arranged in correspondence to one of said pixel electrodes, an average pore size of said polymer component provided above said red regions being larger than that above said green regions, or above said blue regions.

8. The liquid crystal panel according to claim 6, wherein said polymer component included in said liquid crystal/polymer composite comprises an ultra-violet ray setting resin.

9. The liquid crystal panel according to claim 6, wherein an average pore size of said polymer component in said second regions is smaller than that in said first regions and is equal to or less than a wavelength of the incident light into said liquid crystal/polymer composite.

10. The liquid crystal panel according to claim 6, further comprising:

switching elements arranged on said first substrate for each pixel and signal lines for applying signals to the switching elements and the pixel electrodes; and

shading films applied to said switching elements.

11. A viewfinder for a video camera comprising:

a light source;

converging means for converging a light emitted from said light source into a parallel light;

a liquid crystal panel for modulating light output from said light converging means, said liquid crystal panel comprising;

a first substrate having pixel electrodes arranged as a matrix;

a second substrate having a counterelectrode;

a liquid crystal/polymer composite consisting of a liquid crystal component and a polymer component, said composite being interposed between said first and second electrode substrates, and said composite comprising first regions defined on said pixel electrodes and second regions defined between said first regions on said pixel electrodes, an average pore size in said first regions being larger than that in said second regions, and an average pore size of said polymer component in said second region being smaller than that in said first regions and being equal to or less than a wavelength of the incident light into said liquid crystal/polymer composite.

12. The viewfinder according to claim 11, further comprising:

a magnification means for magnifying a display image formed by said liquid crystal panel, said light converging means causing light emitted from said light source to arrive through said liquid crystal panel at a position where an observer can see the magnified display image; and

an eyepiece cover for fixing an eye point of an observer, said eyepiece cover being arranged between said magnification means and a position where said observer can see the light or between said liquid crystal panel and said position.

13. The viewfinder according to claim 11, wherein said convergency lens is a plano-convex lens having a plane surface thereof facing said light source;

said light source comprising a light emitting element and a pin hole plate, said pin hole plate being arranged so that light emitted from the light emitting element radiates through the pin hole.

14. The viewfinder according to claim 11, further comprising a color filter provided above said first or second substrate, wherein said color filter has red regions, green regions, and blue regions, each of said regions being arranged in correspondence to one of said pixel electrodes, an average pore size of said polymer component above the red regions being larger than that above said green regions, or above said blue regions.

15. The viewfinder according to claim 11, wherein switching elements arranged for each pixel and signal lines for applying signals to the switching elements and the pixel electrodes are formed on said first substrate, and shading films are applied to said switching elements.

16. A projection display system comprising:

a light source;

a liquid crystal panel comprising;

a first substrate having pixel electrodes arranged as a matrix;

a second substrate having a counterelectrode; and

a liquid crystal/polymer composite consisting of a liquid crystal component and a polymer component, said composite being interposed between said first and second electrode substrates, and said composite consisting of a first region and a second region defined on each of said pixel electrodes, an average pore size of said polymer component in said first regions being different from that of said second regions;

an optical system comprising a plurality of optical components for introducing a light emitted by said light source to said liquid crystal panel;

a drive means for applying signals to said liquid crystal panel to display an image; and

a projection lens for projecting the light modulated by said display panel.

17. The projection display system according to claim 16, further comprising dichroic mirror dividing light emitted by said light source into three light beams of three wavelengths of blue, green, and red, wherein said liquid crystal panel is arranged for each of optical paths of said three wavelengths.

18. A projection display system comprising:

a light source;

a liquid crystal panel comprising;

a first substrate having pixel electrodes arranged as a matrix;

a second substrate having a counterelectrode; and

a liquid crystal/polymer composite consisting of a liquid crystal component and a polymer component, said composite being interposed between said first and second electrode substrates, and said composite comprising first regions defined on said pixel electrodes and second regions defined between said pixel electrodes, wherein an average pore size in said first regions is larger than that in said second regions;

an optical system comprising a plurality of optical components for introducing light emitted by said light source to said liquid crystal panel;

a drive means for applying signals to said liquid crystal panel to display an image; and

a projection means for projecting light modulated by said display panel.

19. The projection display system according to claim 18, wherein switching elements arranged for each pixel and signal lines for applying signals to said switching elements and said pixel electrodes are formed on said first substrate, and shading films are applied to said switching elements.

20. The projection display system according to claim 18, further comprising a dichroic mirror for dividing light emitted by said light source into three light beams of wavelengths of blue, green, and red, and two additional liquid crystal panels, wherein said liquid crystal panel and two additional liquid crystal panels are arranged so that one panel is disposed in each of the optical paths of said three wavelengths.

21. The projection display system according to claim 20, wherein projection means are provided for each of said liquid crystal panels and said projection means are arranged so that optical images modulated by said liquid crystal panels are projected at the same position on a screen.

22. A liquid crystal panel comprising:

a first substrate having pixel electrodes arranged as a simple matrix;

a second substrate having a second electrode; and

a liquid crystal/polymer composite consisting of a liquid crystal component and a polymer component, said composite being interposed between said first and second substrates;

wherein an average pore size of said polymer component in first regions over the pixel electrodes is larger than that of said polymer component in second regions defined between the first regions.

23. The liquid crystal panel according to claim 22, wherein the average pore size of said polymer component in said first region is between 1 and 2 μ

m.

24. A liquid crystal panel comprising:

a first substrate having pixel electrodes arranged as a matrix, switching elements arranged for each pixel and signal lines for applying signals to the switching elements and the pixel electrodes;

a second substrate having a counterelectrode;

a liquid crystal/polymer composite consisting of a liquid crystal component and a polymer component, said composite being interposed between said first and second electrode substrates; and

shading films applied to said switching elements;

wherein an average pore size of said polymer component in regions over the pixel electrodes is larger than that of said polymer component existing between the regions.