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US5959704A Expired / Lapsed US ⏱️ 0.0 years remaining

Display device having diffraction grating

Assignee: Fujitsu Ltd
•
Filing: 1996-10-30
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Granted: 1999-09-28
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Expires: 2016-10-30
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Abstract

Abstract A display device including a diffraction grating from which a diffracted light of the zeroth order and a diffracted light of the first order having different color light components emerge to establish color separation. An array of micro-lenses is arranged on a liquid crystal panel. The liquid crystal panel has a plurality of picture elements and each picture element includes a plurality of color display dots. The color display dots in each picture element are arranged in the vertical relationship and in the order of wavelength of the light. A green light component of diffracted light of the first order is made incident normal to the liquid crystal panel, and the diffracted light of the zeroth order passes through the liquid crystal panel at a greater angle relative to the normal to the liquid crystal panel.

Inventors

  • 👤 Toshihiro Suzuki
  • 👤 Yukio Iigahama
  • 👤 Hisashi Yamaguchi
  • 👤 Takeshi Gotoh
  • 👤 Tetsuya Hamada
  • 👤 Keiji Hayashi
  • 👤 Junji Tomita
  • 👤 Hirokazu Aritake
  • 👤 Tetsuya Kobayashi
  • 👤 Mari Sugawara
  • 👤 Motohiko Fukuhara
  • 👤 Koji Yoshioka
  • 👤 Kazuhiro Takahara

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-09 18:20
CPC Classifications
G; G02; G02F; G02F1/00; G02F1/01; G02F1/13; G02F1/133; G02F1/1333; G02F1/1335; G02F1/1336; G02F1/133621; H; H04; H04N; H04N9/00; H04N9/12; H04N9/31; H04N9/3102; H04N9/3105; H04N9/3108; H04N9/3141; H04N9/315; H04N9/3167

Claims Analysis

Total Claims: 20
Claim 1
Independent Claim 119 words
A projection type display device comprising: a light source; an optical device having an aperture for converting beams of light emerging from said light source into parallel beams, said aperture having a non-circular shape and mutually perpendicular long and short axis directions; a diffraction grating member arranged to receive the light passing through said optical device; a light valve arranged to receive the light passing through the diffraction grating member to modulate the light to form an image; and a projection lens for projecting the image formed by the light valve; wherein said optical device is arranged so that said short axis direction of said aperture is generally parallel to a color separating plane of said diffraction grating member.
Claim 2
Dependent Claim 119 words
A projection type display device comprising: a light source; an optical device having an aperture for converting beams of light emerging from said light source into parallel beams, said aperture having a non-circular shape and mutually perpendicular long and short axis directions; a diffraction grating member arranged to receive the light passing through said optical device; a light valve arranged to receive the light passing through the diffraction grating member to modulate the light to form an image; and a projection lens for projecting the image formed by the light valve; wherein said optical device is arranged so that said short axis direction of said aperture is generally parallel to a color separating plane of said diffraction grating member.
Claim 3
Dependent Claim 46 words
A projection type display device according to claim 1, wherein the light valve comprises a liquid crystal panel and further comprising a polarizer arranged between the optical device and the diffraction grating member and an analyzer arranged between the liquid crystal panel and the projection lens.
Claim 4
Dependent Claim 31 words
A projection type display device according to claim 2, wherein the polarizer is arranged so that a P-polarized light or an S-polarized light is made incident to the diffraction grating member.
Claim 5
Dependent Claim 36 words
A projection type display device according to claim 2, wherein the analyzer comprises a polarizer plate with an anti-reflection coating and is adhered to a substrate of the liquid crystal panel on the light exit side.
Claim 6
Dependent Claim 30 words
A projection type display device according to claim 2, wherein the analyzer is arranged so that the emerging light is a P-polarized light at the emerging interface of the analyzer.
Claim 7
Dependent Claim 32 words
A projection type display device according to claim 5, wherein the analyzer is arranged so that the light is made incident to the emerging interface of the analyzer at the Brewster's angle.
Claim 8
Dependent Claim 37 words
A projection type display device according to claim 2, wherein the analyzer is adhered to a substrate plate of the liquid crystal panel on the light exit side, and a phase plate is adhered to the analyzer.
Claim 9
Dependent Claim 35 words
A projection type display device according to claim 1, wherein the optical device is arranged so that the long axis direction of the aperture is generally parallel to a longer side of a display dot.
Claim 10
Dependent Claim 46 words
A projection type display device according to claim 1, further comprising a polarization separating means for separating the light passing through the optical device into a P-polarized light and an S-polarized light, the P-polarized light and the S-polarized light forming a polarization separating angle (γ) therebetween.
Claim 11
Dependent Claim 28 words
A projection type display device according to claim 9, wherein the P-polarized light and the S-polarized light are made incident to different display dots in the light valve.
Claim 12
Dependent Claim 57 words
A projection type display device according to claim 9, further comprising a polarization converting means for converting one of the P-polarized light and the S-polarized light separated by the polarization separating means into the other polarized light, the non-converted polarized light and the converted polarized light being made incident to different display dots in the light valve.
Claim 13
Dependent Claim 47 words
A projection type display device according to claim 9, wherein at least one of the short axis direction of the aperture, a polarization separating direction of the polarization separating means and a color separating direction of the diffraction grating member is not parallel to the remaining ones.
Claim 14
Dependent Claim 53 words
A projection type display device according to claim 12, wherein the non-parallel arranged one of the directions is the direction having the greatest angle among an apparent field angle (α) of the aperture, a polarization separating angle (γ) of the polarization separating means and a color separating angle of the diffracted grating member.
Claim 15
Dependent Claim 53 words
A projection type display device according to claim 13, wherein the short axis direction of the aperture is generally perpendicular to the polarization separating direction of the polarization separating means, and the polarization separating direction of the polarization separating means is generally parallel to the color separating plane of the diffraction grating member.
Claim 16
Dependent Claim 25 words
A projection type display device according to claim 1, wherein the optical device comprises an image extinguishing lens having said aperture and a collimating lens.
Claim 17
Dependent Claim 27 words
A projection type display device according to claim 15, further comprising a cut filter arranged in the image extinguishing lens for cutting a predetermined range of wavelength.
Claim 18
Dependent Claim 23 words
A projection type display device according to claim 1, further comprising a field lens arranged between the light valve and the projection lens.
Claim 19
Dependent Claim 27 words
A projection type display device according to claim 1, wherein the projection lens comprises an anamorphic lens in which its magnification changes in two mutually perpendicular directions.
Claim 20
Dependent Claim 23 words
A projection type display device according to claim 1, further comprising a shading layer provided for each unit region of the light valve.

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Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 2002-09-27 2003-03-29 2003-09-28 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2006-09-27 2007-03-29 2007-09-28 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2010-09-27 2011-03-29 2011-09-28 $7700.00 Window Closed / Lapsed

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