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EP0708568A1 Expired / Lapsed EP ⏱️ 0.0 years remaining

Projection-type color display device

Assignee: Sharp Corp
•
Filing: 1995-10-02
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Granted: —
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Expires: 2015-10-02
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Abstract

Abstract The projection-type color display device of the invention includes: a white light source (1); a splitting means (4) for splitting white light emitted from the white light source into a first, a second, and a third beam having respectively different wavelength regions; a modulation means (8) for modulating the first, the second and the third beams; an irradiation means (4) for irradiating the first, the second and the third beams onto a principal surface of the modulation means at respectively different angles; and a projection means (10) for projecting the first, the second and the third beams modulated by the modulation means. In the projection-type color display device, the first beam includes a color beam having a weakest intensity among the beams in three primary colors contained in the white light; and a direction of the first beam incident onto the principal surface of the modulation means is closer to a normal of the principal surface of the modulation means as compared with the second and the third beams.

Inventors

  • 👤 Naoyuki Tanaka
  • 👤 Hiroshi Hamada
  • 👤 Hiroshi Nakanishi
  • 👤 Hideki Ohshima

Bibliographic Details

Application Number —
Jurisdiction EP
Data Source google_patents
Last Synchronized 2026-11-09 13:42
CPC Classifications
G; G02; G02B; G02B27/00; G02B27/10; G02B27/14; G02B27/148; G02F; G02F1/00; G02F1/01; G02F1/13; G09; G09F; G09F9/00; G09F9/30; G09F9/35; H; H04; H04N; H04N9/00; H04N9/12; H04N9/31; H04N9/3102; H04N9/3105; H04N9/3108; G02F1/133; G02F1/1333; G02F1/1335; G02F1/1336; G02F1/133621; G02F1/133623

Claims Analysis

Total Claims: 7
Claim 1
Independent Claim 156 words
A projection-type color display device comprising: a white light source; a splitting means for splitting white light emitted from the white light source into a first, a second, and a third beam having respectively different wavelength regions; a modulation means for modulating the first, the second and the third beams; an irradiation means for irradiating the first, the second and the third beams onto a principal surface of the modulation means at respectively different angles; and a projection means for projecting the first, the second and the third beams modulated by the modulation means, wherein the first beam includes a color beam having a weakest intensity among the beams in three primary colors contained in the white light; and a direction of the first beam incident onto the principal surface of the modulation means is closer to a normal of the principal surface of the modulation means as compared with the second and the third beams.
Claim 2
Dependent Claim 77 words
A projection-type color display device according to claim 1, wherein the modulation means comprises a first, a second and a third pixel and a microlens disposed so as to correspond to the first, the second and the third pixels; the first, the second and the third beams are irradiated onto the microlens at respectively different angles; and the first, the second and the third beams are incident onto the first, the second and the third pixels, respectively.
Claim 3
Dependent Claim 53 words
A projection-type color display device according to claim 1, wherein the projection means is a projection lens having an F value of a number N, and the number N is larger than 1/(2 ˙ tan θ' max ), where θ' max is a maximum angle of the beam outgoing from the modulation means.
Claim 4
Dependent Claim 36 words
A projection-type color display device according to claim 1, wherein the white light source is a metal halide lamp, and the first beam is red, the second beam is blue and the third beam is green.
Claim 5
Dependent Claim 35 words
A projection-type color display device according to claim 1, wherein the white light source is a halogen lamp, and the first beam is blue, the second beam is red and the third beam is green.
Claim 6
Dependent Claim 93 words
A projection-type color display device according to claim 1, wherein the splitting means includes a first, a second and a third dichroic mirror; the first dichroic mirror receives the white light and reflects at least one of the second and third beams; the second dichroic mirror receives light transmitted through the first dichroic mirror and reflects the first beam; and the third dichroic mirror receives light transmitted through the second dichroic mirror, reflects one of the second and third beams, which has transmitted the second dichroic mirror, and functions as the irradiation means.
Claim 7
Dependent Claim 97 words
A display device comprising splitting means (4) for splitting light from a light source (1) into at least two beams and directing the beams onto a modulation means (8); wherein the beams contain light of different wavelengths to one another; and wherein the splitting means (4) is arranged to direct the beams onto an input surface of the modulation means (8) so that the angle between the normal of the input surface of the modulation means and the beam having the lowest intensity is smaller than the angle between the normal and the or each other beam.

References Cited (Backward Citations)

EP0060072A1 Cited
JPS59230383A Cited
JPS62127768A Cited
WO1989006417A1 Cited
EP0465171A2 Cited
JPH0460538A Cited
FR2699688A1 Cited
EP0633702A1 Cited

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