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US4126383A Expired / Lapsed US ⏱️ 0.0 years remaining

Electrooptic display device

Assignee: BBC Brown Boveri AG Switzerland
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Filing: 1977-05-02
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Granted: 1978-11-21
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Expires: 1997-05-02
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Abstract

Abstract An electrooptic display device which can be operated either in the transmission or reflection mode. The display device consists of a liquid crystal display cell and a semitransparent reflector located in or on a circuit board having a light emitting element disposed therein and characterized by at least one light conducting region.

Inventors

  • 👤 Rino Doriguzzi
  • 👤 Markus Egloff
  • 👤 Meinolph Kaufmann
  • 👤 Terry J. Scheffer

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-23 10:23
CPC Classifications
G; G02; G02F; G02F1/00; G02F1/01; G02F1/13; G02F1/133; G02F1/1333; G02F1/1335; G02F1/1336; G02F1/133615; G04; G04G; G04G9/00; G04G9/0023; G04G9/0029; G04G9/0035; G04G9/0041; G09; G09F; G09F9/00; G09F9/30

Claims Analysis

Total Claims: 13
Claim 1
Independent Claim 66 words
An electrooptical display device for transmissive or reflective operation comprising: a circuit board having at least one light conducting region and having electrical leads mounted thereon; a liquid crystal display cell disposed adjacent the light conducting region of the circuit board and having a semitransparent reflector attached thereto; and at least one light emitting element located in the circuit board for illuminating the light conducting region.
Claim 2
Dependent Claim 66 words
An electrooptical display device for transmissive or reflective operation comprising: a circuit board having at least one light conducting region and having electrical leads mounted thereon; a liquid crystal display cell disposed adjacent the light conducting region of the circuit board and having a semitransparent reflector attached thereto; and at least one light emitting element located in the circuit board for illuminating the light conducting region.
Claim 3
Dependent Claim 18 words
An electrooptical display device as recited in claim 1 wherein the light emitting element comprises a miniature lamp.
Claim 4
Dependent Claim 20 words
An electrooptical display device as recited in claim 2, wherein said circuit board contains at least a partially reflective layer.
Claim 5
Dependent Claim 37 words
An electrooptical display device as recited in claim 3, wherein said reflective layer comprises a plastic film upon which reflective regions of a material selected from the group consisting of aluminum, silver, gold, and chromium are evaporated.
Claim 6
Dependent Claim 38 words
An electrooptical display device as recited in claim 3, wherein said reflective layer comprises a fine meshed plastic screen upon which a coating of a material selected from the group of aluminum, silver, gold or chromium is evaporated.
Claim 7
Dependent Claim 22 words
An electrooptical display device as recited in claim 1, wherein said light conducting region of the circuit board contains light scattering centers.
Claim 8
Dependent Claim 36 words
An electrooptical display device as recited in claim 6, wherein said light scattering centers comprise powdered materials selected from the group consisting of MgO, Al 2 O 3 , TiO 2 , and BaSO 4 .
Claim 9
Dependent Claim 29 words
An electrooptical display device as recited in claim 6, wherein said light scattering centers are produced by gluing a mat plastic film onto the surface of the circuit board.
Claim 10
Dependent Claim 29 words
An electrooptical display device as is described in claim 6, wherein said light scattering centers are produced by roughening at least parts of the surface of the circuit board.
Claim 11
Dependent Claim 25 words
An electrooptical display device as recited in claim 6, wherein said light scattering centers are formed by tiny gas bubbles embedded in the circuit board.
Claim 12
Dependent Claim 39 words
An electrooptical display device as recited in claim 6, wherein said light scattering centers are formed by a layer of woven material whose refractive index is different from the refractive index of the surrounding material forming the circuit board.
Claim 13
Dependent Claim 82 words
An electrooptical display device as is described in claim 1, wherein the circuit board consists of: six layers of light conducting polyester resin, one of the layers being underneath the liquid crystal cell; four layers of fiberglass cloth alternating with the polyester resin layers starting with the polyester resin layer that is underneath the liquid crystal cell; and a reflective layer located between the last two layers of polyester resin, said layer consisting of a substrate upon which are deposited reflecting regions.

References Cited (Backward Citations)

US4033672A Cited
US3748018A Cited
US4036550A Cited
US3864905A Cited
US3984176A Cited
US4043636A Cited
US3994564A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1981-11-20 1982-05-22 1982-11-21 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1985-11-20 1986-05-22 1986-11-21 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1989-11-20 1990-05-22 1990-11-21 $7700.00 Window Closed / Lapsed

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