US5040098A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Backlight for an electronic display
Assignee: Fujitsu Kasei Ltd
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Filing: 1990-04-11
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Granted: 1991-08-13
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Expires: 2010-04-11
Abstract
Abstract A backlight having a reflection plate, a diffusion plate, a transparent light guide plate held between the diffusion plate and the reflection plate and having a reflection and diffusion surface adjacent to the reflection plate and a recessed light emitting surface adjacent to the diffusion plate, so that a space is defined between the recessed light emitting surface and the bottom surface of the diffusion plate adjacent thereto, a holder connected to the diffusion plate to define accommodation spaces between the opposite ends of the transparent light guide plate and the holder, and line light sources located in the accommodation spaces.
Inventors
- 👤 Akira Tanaka
- 👤 Shinpei Nagatani
- 👤 Masahiro Tomatsu
- 👤 Kazumasa Kaiwa
- 👤 Kazuaki Yamagishi
- 👤 Katsumi Yashiro
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 06:55
CPC Classifications
G; G09; G09F; G09F13/00; G09F13/04; G02; G02B; G02B6/00; G02B6/0001; G02B6/0011; G02B6/0013; G02B6/0015; G02B6/002; G02B6/0033; G02B6/0035; G02B6/0045; G02B6/0046; G09F13/0409; G02B6/0023; G02B6/0031; G02B6/005; G02B6/0051
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
136 words
A backlight, comprising: a reflection plate; a diffusion plate; a transparent light guide plate held between the diffusion plate and the reflection plate, said light guide plate having rounded light receiving surfaces on opposite ends thereof, having a reflection and diffusion surface adjacent to the reflection plate, and having a recessed light emitting surface adjacent to the diffusion plate, wherein a space is defined between the recessed light emitting surface and a bottom surface of the diffusion plate adjacent thereto; a holder connected to the diffusion plate wherein said rounded light receiving surfaces and said holder define accommodation spaces in the transparent light guide plate; and line light sources located in the accommodation spaces wherein the line light sources are surrounded by the holder and the rounded light receiving surfaces of the transparent light guide plate.
Claim 2
Dependent Claim
136 words
A backlight, comprising: a reflection plate; a diffusion plate; a transparent light guide plate held between the diffusion plate and the reflection plate, said light guide plate having rounded light receiving surfaces on opposite ends thereof, having a reflection and diffusion surface adjacent to the reflection plate, and having a recessed light emitting surface adjacent to the diffusion plate, wherein a space is defined between the recessed light emitting surface and a bottom surface of the diffusion plate adjacent thereto; a holder connected to the diffusion plate wherein said rounded light receiving surfaces and said holder define accommodation spaces in the transparent light guide plate; and line light sources located in the accommodation spaces wherein the line light sources are surrounded by the holder and the rounded light receiving surfaces of the transparent light guide plate.
Claim 3
Dependent Claim
24 words
A backlight according to claim 1, wherein said holder has inner reflection surface portions facing the line light sources and defining the accommodation spaces.
Claim 4
Dependent Claim
18 words
A backlight according to claim 2, wherein said recessed light emitting surface has a generally V-shape cross section.
Claim 5
Dependent Claim
28 words
A backlight according to claim 3, wherein, in said generally V-shaped light emitting surface, an apex of a V-shape in cross section is located at the center thereof.
Claim 6
Dependent Claim
19 words
A backlight according to claim 4, wherein said inner reflection surface portions of the holder are smoothly rounded surfaces.
Claim 7
Dependent Claim
15 words
A backlight according to claim 1, wherein said line light sources are cold cathode tubes.
Claim 8
Dependent Claim
15 words
A backlight according to claim 1, wherein said line light sources are hot cathode tubes.
Claim 9
Dependent Claim
31 words
A backlight according to claim 1, wherein the reflection and diffusion surface of the transparent light guide plate adjacent to the reflection plate is subjected to a rough finish surface treatment.
Claim 10
Dependent Claim
29 words
A backlight according to claim 1, wherein the space between the diffusion plate and the recessed light emitting surface of the transparent light guide plate is an air space.
Claim 11
Dependent Claim
138 words
A backlight, comprising: a reflection plate; a diffusion plate; a transparent light guide plate held between the diffusion plate and the reflection plate, said light guide plate having a rounded light receiving surface on one end, and having a reflection and diffusion surface adjacent to the reflection plate, and having a recessed light emitting surface adjacent to the diffusion plate, wherein a space is defined between the recessed light emitting surface and a bottom surface of the diffusion plate adjacent thereto; a holder connected to the diffusion plate wherein said rounded light receiving surface and said holder defines an accommodation space on the transparent light guide plate; and line light source located in the accommodation space wherein the line light source is surrounded by the holder and the rounded light receiving surface of the transparent light guide plate.
Claim 12
Dependent Claim
138 words
A backlight, comprising: a reflection plate; a diffusion plate; a transparent light guide plate held between the diffusion plate and the reflection plate, said light guide plate having a rounded light receiving surface on one end, and having a reflection and diffusion surface adjacent to the reflection plate, and having a recessed light emitting surface adjacent to the diffusion plate, wherein a space is defined between the recessed light emitting surface and a bottom surface of the diffusion plate adjacent thereto; a holder connected to the diffusion plate wherein said rounded light receiving surface and said holder defines an accommodation space on the transparent light guide plate; and line light source located in the accommodation space wherein the line light source is surrounded by the holder and the rounded light receiving surface of the transparent light guide plate.
Claim 13
Dependent Claim
25 words
A backlight according to claim 10, wherein said holder has an inner reflection surface portion facing the line light source and defining the accommodation space.
Claim 14
Dependent Claim
20 words
A backlight according to claim 10, wherein said inner reflection surface portion of the holder is a smoothly rounded surface.
Claim 15
Dependent Claim
18 words
A backlight according to claim 12 wherein said recessed light emitting surface has an eccentric V-shape cross section.
Claim 16
Dependent Claim
32 words
A backlight according to claim 13, wherein said eccentric V-shaped emitting surface has an apex of a V-shape thereof located closer to the end thereof that is far from the accommodation space.
Claim 17
Dependent Claim
29 words
A backlight according to claim 14, wherein the space between the diffusion plate and the recessed light emitting surface of the transparent light guide plate is an air space.
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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) | 1994-08-12 | 1995-02-11 | 1995-08-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1998-08-12 | 1999-02-11 | 1999-08-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2002-08-12 | 2003-02-11 | 2003-08-13 | $7700.00 | Window Closed / Lapsed |