Patent US5274480A successfully refreshed from Google Patents.
US5274480A
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Projection type display apparatus having an aperture stop means including non-circular openings
Assignee: AGC Inc
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Filing: 1991-11-27
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Granted: 1993-12-28
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Expires: 2011-11-27
Abstract
Abstract A projection type display apparatus comprises a light source optical system having an anisotropic luminance distribution, a transparent-scattering type display element for controlling light emitted from the light source optical system and a projection optical system having an aperture which projects the transmitted light, wherein the aperture of the projection optical system is an aperture having a non-circular opening which is disposed in the vicinity of the focal point of the transmitted light of the transparent-scattering type display element.
Inventors
- 👤 Yoshinori Hirai
- 👤 Yoshiharu Ooi
- 👤 Tomoki Gunjima
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 15:05
CPC Classifications
H; H04; H04N; H04N9/00; H04N9/12; H04N9/31; H04N9/3141; H04N9/315
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
115 words
A projection type display apparatus comprising a light source optical system, a transparent-scattering type display element for controlling light emitted from the light source optical system and a projection optical system having an aperture stop means which projects the transmitted light, characterized in that the light source optical system emits a plurality of light fluxes to the transparent-scattering type display element, and the aperture stop means of the projection optical system is an aperture stop means having openings, wherein one or more of the openings have other than a single circular shape, which aperture stop means is disposed in the vicinity of the focal point of the transmitted light of the transparent-scattering type display element.
Claim 2
Dependent Claim
115 words
A projection type display apparatus comprising a light source optical system, a transparent-scattering type display element for controlling light emitted from the light source optical system and a projection optical system having an aperture stop means which projects the transmitted light, characterized in that the light source optical system emits a plurality of light fluxes to the transparent-scattering type display element, and the aperture stop means of the projection optical system is an aperture stop means having openings, wherein one or more of the openings have other than a single circular shape, which aperture stop means is disposed in the vicinity of the focal point of the transmitted light of the transparent-scattering type display element.
Claim 3
Dependent Claim
26 words
The projection type display apparatus according to claim 1, wherein the openings comprise a plurality of non-circular openings which correspond to the plurality of light fluxes.
Claim 4
Dependent Claim
47 words
The projection type display apparatus according to claim 1, wherein the following relation is satisfied: 0.2S.sub.1 <S.sub.B <0.6S.sub.1 ( 2) where S B is the surface area of all the openings and S 1 is the surface area of the smallest circle which includes all the openings.
Claim 5
Dependent Claim
50 words
The projection type display apparatus according to claim 2, wherein the following relation is satisfied: 0.2S.sub.2 <S.sub.C <0.7S.sub.2 ( 3) where S C is the surface area of each of the openings, and S 2 is the surface area of a circle which is circumscribed to each of the openings.
Claim 6
Dependent Claim
53 words
The projection type display apparatus according to claim 2, wherein the shape of each of the openings of the aperture stop means satisfies the relation of: the width of the opening at the central portion of the long axis ≧ the width of the opening at an edge portion of the long axis.
Claim 7
Dependent Claim
23 words
The projection type display apparatus according to claim 5, wherein each of the openings of the aperture stop means has a rectangular shape.
Claim 8
Dependent Claim
21 words
The projection type display apparatus according to claim 5, wherein each of the openings of the aperture stop means is elliptical.
Claim 9
Dependent Claim
40 words
The projection type display apparatus according to claim 5, wherein each of the openings of the aperture stop means has an outer configuration which is formed by putting a circular arc at each of the opposing sides of a rectangle.
Claim 10
Dependent Claim
117 words
The projection type display apparatus according to claim 1, wherein said transparent-scattering type display element is a transparent-scattering type liquid crystal display element which comprises a liquid crystal and solidified matrix composite held between substrates each having an electrode, in which a nematic liquid crystal is dispersed and held in a solidified matrix; the refractive index of the liquid crystal is changed under the condition of application of a voltage in such manner that light is transmitted when the refractive index of the liquid crystal is substantially in coincidence with the refractive index of the solidified matrix in one state, and the light is scattered when the former doesn't coincide with the latter in the other state.
Claim 11
Dependent Claim
20 words
The projection type display apparats of claim 1, wherein each of sad openings have other than a singular circular shape.
Claim 12
Dependent Claim
46 words
The projection type display apparatus of claim 1, consisting of a light source optical system, a single transparent-scattering type display element for controlling light emitted from the light source optical system and a projection optical system having an aperture stop means which projects the transmitted light.
Claim 13
Dependent Claim
31 words
The projection type display apparatus of claim 1, wherein the aperture stop means is disposed between the transparent-scattering type display element and the projection optical system excluding the aperture stop means.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1996-12-27 | 1997-06-28 | 1997-12-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2000-12-27 | 2001-06-28 | 2001-12-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2004-12-27 | 2005-06-28 | 2005-12-28 | $7700.00 | Window Closed / Lapsed |