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US6612702B1 Expired / Lapsed US ⏱️ 0.0 years remaining

Projection display device

Assignee: Seiko Epson Corp
•
Filing: 1999-02-09
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Granted: 2003-09-02
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Expires: 2019-02-09
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Abstract

Abstract The invention accurately sets a polarization direction of a polarization element, and prevents deterioration of the usage efficiency of the light and a reduction in image contrast. Field lenses are provided on a projection display device. A polarizer is placed on a flat surface of a field lens. The flat surface of the field lens is provided with a reference shape to place the polarizer at the end thereof. The reference shape may be one or more planes provided on the end of the field lens. In addition, the reference shape may be a straight line drawn on the flat surface of the field lens.

Inventors

  • 👤 Tomiyoshi Ushiyama
  • 👤 Akitaka Yajima

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-09 18:08
CPC Classifications
G; G03; G03B; G03B21/00; G03B21/005; G03B21/006

Claims Analysis

Total Claims: 20
Claim 1
Independent Claim 126 words
A projector, comprising: an illumination optical system that emits illuminating light; a light valve that modulates the illuminating light emitted from said illumination optical system to emit a modulated light, the light valve having an incident surface, a projection optical system that projects the modulated light emitted from the light valve, and a lens having a first side, a second side and a peripheral edge, said lens provided on a side of the incident surface of the light valve, when said lens is viewed in a direction along and parallel to an optical axis of said lens at least one part of the peripheral edge of the lens is a straight edge and another part of the peripheral edge of the lens is a curved edge.
Claim 2
Dependent Claim 126 words
A projector, comprising: an illumination optical system that emits illuminating light; a light valve that modulates the illuminating light emitted from said illumination optical system to emit a modulated light, the light valve having an incident surface, a projection optical system that projects the modulated light emitted from the light valve, and a lens having a first side, a second side and a peripheral edge, said lens provided on a side of the incident surface of the light valve, when said lens is viewed in a direction along and parallel to an optical axis of said lens at least one part of the peripheral edge of the lens is a straight edge and another part of the peripheral edge of the lens is a curved edge.
Claim 3
Dependent Claim 25 words
The projector according to claim 1 , wherein the lens has a flat surface and further including a polarization element provided on the flat surface.
Claim 4
Dependent Claim 25 words
The projector according to claim 1 , wherein the lens has a flat surface and further including a dichroic film provided on the flat surface.
Claim 5
Dependent Claim 25 words
A projector according to claim 1 , the straight edge being formed so as to provide the periphery edge of the lens with multiple concavities.
Claim 6
Dependent Claim 25 words
The projector according to claim 4 , wherein the lens has a flat surface and further including a polarization element provided on the flat surface.
Claim 7
Dependent Claim 25 words
The projector according to claim 4 , wherein the lens has a flat surface and further including a dichroic film provided on the flat surface.
Claim 8
Dependent Claim 25 words
A projector according to claim 1 , the straight edge being formed so as to provide the periphery edge of the lens with a concavity.
Claim 9
Dependent Claim 25 words
The projector according to claim 7 , wherein the lens has a flat surface and further including a polarization element provided on the flat surface.
Claim 10
Dependent Claim 25 words
The projector according to claim 7 , wherein the lens has a flat surface and further including a dichroic film provided on the flat surface.
Claim 11
Dependent Claim 191 words
A projector, comprising: an illumination optical system that emits illuminating light; a color light separation section that separates the illuminating light emitted from said illumination optical system into three color light; three light valves that modulate the three color light to emit a modulated light, each of the light valves having an incident surface, three lenses placed on a side of the incident surface of the light valves, each lens having a first side, a second side and a peripheral edge, respectively, at least one of said three lenses having a shape such that when said at least one lens is viewed in a direction along and parallel to an optical axis of said at least one lens at least one part of the peripheral edge of said at least one lens is a straight edge and another part of the peripheral edge of said at least one lens is a curved edge; a color light synthesizing section that synthesizes the modulated light emitted from said three light valves to emit a synthesized light; and a projection optical system that projects the synthesized light emitted from the color light synthesizing section.
Claim 12
Dependent Claim 191 words
A projector, comprising: an illumination optical system that emits illuminating light; a color light separation section that separates the illuminating light emitted from said illumination optical system into three color light; three light valves that modulate the three color light to emit a modulated light, each of the light valves having an incident surface, three lenses placed on a side of the incident surface of the light valves, each lens having a first side, a second side and a peripheral edge, respectively, at least one of said three lenses having a shape such that when said at least one lens is viewed in a direction along and parallel to an optical axis of said at least one lens at least one part of the peripheral edge of said at least one lens is a straight edge and another part of the peripheral edge of said at least one lens is a curved edge; a color light synthesizing section that synthesizes the modulated light emitted from said three light valves to emit a synthesized light; and a projection optical system that projects the synthesized light emitted from the color light synthesizing section.
Claim 13
Dependent Claim 30 words
The projector according to claim 10 , wherein at least one of the three lens has a flat surface and further including a polarization element provided on the flat surface.
Claim 14
Dependent Claim 30 words
The projector according to claim 10 , wherein at least one of the three lenses has a flat surface and further including a dichroic film provided on the flat surface.
Claim 15
Dependent Claim 25 words
A projector according to claim 10 , the straight edge being formed so as to provide the periphery edge of the lens with a concavity.
Claim 16
Dependent Claim 30 words
The projector according to claim 13 , wherein at least one of the three lenses has a flat surface and further including a polarization element provided on the flat surface.
Claim 17
Dependent Claim 30 words
The projector according to claim 13 , wherein at least one of the three lenses has a flat surface and further including a dichroic film provided on the flat surface.
Claim 18
Dependent Claim 25 words
A projector according to claim 10 , the straight edge being formed so as to provide the periphery edge of the lens with multiple concavities.
Claim 19
Dependent Claim 30 words
The projector according to claim 16 , wherein at least one of the three lenses has a flat surface and further including a polarization element provided on the flat surface.
Claim 20
Dependent Claim 30 words
The projector according to claim 16 , wherein at least one of the three lenses has a flat surface and further including a dichroic film provided on the flat surface.

References Cited (Backward Citations)

USH76H Cited
US4917465A Cited
US5117311A Cited
US5825022A Cited
US5325218A Cited
US5835279A Cited
US5743610A Cited
US6144505A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 2006-09-01 2007-03-03 2007-09-02 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2010-09-01 2011-03-03 2011-09-02 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2014-09-01 2015-03-03 2015-09-02 $7700.00 Window Closed / Lapsed

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