Patent US5587816A successfully refreshed from Google Patents.
US5587816A
Expired / Lapsed
US
⏱️ 0.0 years remaining
LCD device including an illumination device having a polarized light separating sheet between a light guide and the display
Assignee: AGC Inc
•
Filing: 1995-10-19
•
Granted: 1996-12-24
•
Expires: 2015-10-19
Abstract
Abstract An illumination device for a direct viewing type display element comprising a flat light guide; a light source set such that light is incident on a side portion of said flat light guide; a polarized light separating flat set on a first side of a light emitting side of the flat light guide for transmitting a p polarized light component and reflecting at least a portion of an s polarized light component with respect to a light ray substantially having a predetermined direction of incidence; and a light reflecting sheet disposed on a second side opposite to said light emitting side of the flat light guide in parallel with the light emitting site.
Inventors
- 👤 Tomoki Gunjima
- 👤 Yoshiharu Ooi
- 👤 Masao Ozeki
- 👤 Hiroaki Ito
- 👤 Hiroshi Hasebe
- 👤 Tetsuro Matsumoto
- 👤 Yutaka Nakagawa
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 04:44
CPC Classifications
G; G02; G02B; G02B6/00; G02B6/0001; G02B6/0011; G02B6/0033; G02B6/0056; G02F; G02F1/00; G02F1/01; G02F1/13; G02F1/133; F; F21; F21V; F21V9/00; F21V9/14; G02F1/1333; G02F1/1335; G02F1/1336; G02F1/13362; G02B6/0035; G02B6/0038; G02B6/005; G02B6/0053; G02B6/0055; G02F1/133528; G02F1/13355; G02F1/133615
Claims Analysis
Total Claims: 22
Claim 1
Independent Claim
168 words
An illumination device for a direct viewing type display element, comprising: a flat light guide; a light source set such that light is incident on a side portion of said flat light guide; a polarized light separating sheet set on a light emitting side of the flat light guide for transmitting a p polarized light component and reflecting at least a portion of an s polarized light component with respect to a light ray substantially having a predetermined direction of incidence; and a light reflecting sheet disposed on another side opposite to and facing said light emitting side of the flat light guide in parallel with the emitting side, said light reflecting sheet converting said portion of s polarized light component reflected by said polarized light separating sheet into p polarized light and reflecting the converted p polarized light to said polarized light separating sheet for transmission of the converted p polarized light through said polarized light separating sheet in overlapping relationship with the p polarized light component.
Claim 2
Dependent Claim
168 words
An illumination device for a direct viewing type display element, comprising: a flat light guide; a light source set such that light is incident on a side portion of said flat light guide; a polarized light separating sheet set on a light emitting side of the flat light guide for transmitting a p polarized light component and reflecting at least a portion of an s polarized light component with respect to a light ray substantially having a predetermined direction of incidence; and a light reflecting sheet disposed on another side opposite to and facing said light emitting side of the flat light guide in parallel with the emitting side, said light reflecting sheet converting said portion of s polarized light component reflected by said polarized light separating sheet into p polarized light and reflecting the converted p polarized light to said polarized light separating sheet for transmission of the converted p polarized light through said polarized light separating sheet in overlapping relationship with the p polarized light component.
Claim 3
Dependent Claim
47 words
The illumination device for a direct viewing type display element according to claim 1, wherein the polarized light separating sheet is comprising a multi-layered structure wherein light transmitting media having a relatively large refractive index and light transmitting media having a relatively small refractive index are laminated.
Claim 4
Dependent Claim
51 words
The illumination device for a direct viewing type display element according to claim 1, wherein the polarized light separating sheet comprises a transparent supporter and at least one dielectric thin film laminated on said transparent supportor having a thickness which is equal to or smaller than a wavelength of visible light.
Claim 5
Dependent Claim
32 words
The illumination device for a direct viewing type display element according to claim 1, wherein the polarized light separating sheet comprises a plurality of laminated transparent polymer layers having different refractive indices.
Claim 6
Dependent Claim
66 words
A liquid crystal display device, wherein the illumination device according to claim 1 is disposed on a rear side of a direct viewing type liquid crystal display element such that a principle polarization direction of emitted light from the illumination device substantially agrees with a direction of an optical axis of polarization of a polarizing sheet on a light-incident side of a liquid crystal display element.
Claim 7
Dependent Claim
59 words
The liquid crystal display device according to claim 5 further comprising: a light deflecting means disposed between the polarized light separating sheet and the liquid crystal display element for deflecting a direction of a light ray maximizing a light intensity among light distributing directions to a direction substantially perpendicular to a display face of the liquid crystal display element.
Claim 8
Dependent Claim
36 words
The liquid crystal display device according to claim 5, further comprising: a means for rotating polarization direction disposed between the illumination device and the liquid crystal display element for rotating the principle direction of emitted light.
Claim 9
Dependent Claim
122 words
An illumination device for a direct viewing type display element, comprising: a flat light emitting means for emitting a diffused light including a first polarized light component having a first direction of polarization and a second polarized light component having a second direction of polarization perpendicular to the first direction of polarization; and a polarized light converting and emitting means disposed in an optical path of a light emitted from said flat light emitting means for emitting said first polarized light component and for emitting, in overlapping relationship with the emitted first polarized light component, at least a portion of said second polarized light component after selectively converting said portion of said second polarized light component into the first polarized light component.
Claim 10
Dependent Claim
122 words
An illumination device for a direct viewing type display element, comprising: a flat light emitting means for emitting a diffused light including a first polarized light component having a first direction of polarization and a second polarized light component having a second direction of polarization perpendicular to the first direction of polarization; and a polarized light converting and emitting means disposed in an optical path of a light emitted from said flat light emitting means for emitting said first polarized light component and for emitting, in overlapping relationship with the emitted first polarized light component, at least a portion of said second polarized light component after selectively converting said portion of said second polarized light component into the first polarized light component.
Claim 11
Dependent Claim
167 words
An illumination device for a direct viewing type display element, comprising: a flat light guide; a light source set such that light is incident on a side portion of said flat light guide; a polarized light separating sheet set on a light emitting side of the flat light guide for transmitting a p polarized light component and reflecting at least a portion of an s polarized light component with respect to light rays substantially having a predetermined direction of incidence; and a light reflecting sheet disposed on another side opposite to and facing said light emitting side of the flat light guide in parallel with the emitting side, said light reflecting sheet converting said portion of s polarized light component reflected by said polarized light separating sheet into p polarized light and reflecting the converted p polarized light to said polarized light separating sheet for transmission of the converted p polarized light through said polarized light separating sheet in overlapping relationship with the p polarized light component.
Claim 12
Dependent Claim
167 words
An illumination device for a direct viewing type display element, comprising: a flat light guide; a light source set such that light is incident on a side portion of said flat light guide; a polarized light separating sheet set on a light emitting side of the flat light guide for transmitting a p polarized light component and reflecting at least a portion of an s polarized light component with respect to light rays substantially having a predetermined direction of incidence; and a light reflecting sheet disposed on another side opposite to and facing said light emitting side of the flat light guide in parallel with the emitting side, said light reflecting sheet converting said portion of s polarized light component reflected by said polarized light separating sheet into p polarized light and reflecting the converted p polarized light to said polarized light separating sheet for transmission of the converted p polarized light through said polarized light separating sheet in overlapping relationship with the p polarized light component.
Claim 13
Dependent Claim
51 words
The illumination device for a direct viewing type display element according to claim 9, wherein the polarized light separating sheet comprises a transparent supporter and at least one dielectric thin film laminated on said transparent supporter having a thickness which is equal to or smaller than a wavelength of visible light.
Claim 14
Dependent Claim
58 words
The illumination device for a direct viewing type display element according to claim 9, wherein the polarized light separating sheet is composed of a multi-layer structure including alternately laminated light transmitting media, having a refractive index, n 0 , and other transmitting media, having a refractive index, n 1 , smaller than the refractive index n 0 .
Claim 15
Dependent Claim
42 words
The illumination device for a direct viewing type display element according to claim 9, wherein a λ/4 phase interference plate is provided on the back face of the light guide and a side face of the light guide opposing the light source.
Claim 16
Dependent Claim
42 words
The illumination device for a direct viewing type display element according to claim 10, wherein a λ/4 phase interference plate is provided on the back face of the light guide and a side face of the light guide opposing the light source.
Claim 17
Dependent Claim
27 words
The illumination device for a direct viewing type display element according to claim 9, wherein a prism shape is formed on a surface of the light guide.
Claim 18
Dependent Claim
23 words
The illumination device for a direct viewing type display element according to claim 14, wherein the prism shape is a lenticular lens array.
Claim 19
Dependent Claim
19 words
The illumination device for a direct viewing type display element according to claim 9, further comprising a light deflector.
Claim 20
Dependent Claim
35 words
The illumination device for a direct viewing type display element according to claim 16, wherein a micro lens array or prism array having a lenticular shape or Fresnel shape is employed as the light deflector.
Claim 21
Dependent Claim
144 words
An illumination device for a direct viewing type display element, comprising: a flat light guide; a light source set such that light is incident on a side portion of said flat light guide; a polarized light separating sheet set on a light emitting side of the flat light guide for transmitting a p polarized light component and reflecting at least a portion of an s polarized light component with respect to a light ray substantially having a predetermined direction of incidence; and a light reflecting sheet disposed on another side opposite to and facing said light emitting side of the flat light guide in parallel with the emitting side, wherein said polarized light separating sheet is planar and parallel to the light emitting side of the flat light guide and is set in proximity to the flat light guide in the light emitting direction.
Claim 22
Dependent Claim
144 words
An illumination device for a direct viewing type display element, comprising: a flat light guide; a light source set such that light is incident on a side portion of said flat light guide; a polarized light separating sheet set on a light emitting side of the flat light guide for transmitting a p polarized light component and reflecting at least a portion of an s polarized light component with respect to a light ray substantially having a predetermined direction of incidence; and a light reflecting sheet disposed on another side opposite to and facing said light emitting side of the flat light guide in parallel with the emitting side, wherein said polarized light separating sheet is planar and parallel to the light emitting side of the flat light guide and is set in proximity to the flat light guide in the light emitting direction.
References Cited (Backward Citations)
US4214257A
Cited
US4492449A
Cited
US4646215A
Cited
US4798448A
Cited
US5064276A
Cited
US5042921A
Cited
US5200843A
Cited
US5153752A
Cited
US5101193A
Cited
JPH04184429A
Cited
US5467417A
Cited
US5418631A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1999-12-24 | 2000-06-24 | 2000-12-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2003-12-24 | 2004-06-24 | 2004-12-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2007-12-24 | 2008-06-24 | 2008-12-24 | $7700.00 | Window Closed / Lapsed |