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US4062009A Expired / Lapsed US ⏱️ 0.0 years remaining

Electrophoretic display device

Assignee: Thales SA
•
Filing: 1976-07-13
•
Granted: 1977-12-06
•
Expires: 1996-07-13
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Abstract

Abstract An information display device utilizing the phenomenon of electrophoresis. It comprises two transparent electrodes parallel to one another and assembled in order to constitute a sealed cell filled with a colored fluid, and a thin porous diaphragm scattering the light in a color differing from that of the fluid, the diaphragm being arranged in the vessel parallel to the electrodes. The diaphragm displaces by electrophoresis, from one electrode to the other, under the action of potential differences applied to the electrodes.

Inventors

  • 👤 Yvan Raverdy
  • 👤 Jean Luc Ploix

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-26 09:35
CPC Classifications
G; G09; G09F; G09F9/00; G09F9/30; G09F9/37; G09F9/372

Claims Analysis

Total Claims: 15
Claim 1
Independent Claim 177 words
A display device using electrophoresis, comprising two substrates, a front substrate disposed towards incident light and a back substrate, said substrates carrying electrodes, at least said front substrate and its electrodes being transparent, said substrates being substantially parallel and attached together in order to form a closed vessel filled with a resistive fluid; said display device further comprising a thin electrophoretically displaceable diaphragm arranged in said vessel and permeable to said fluid, said diaphragm being capable of scattering the incident light in a colour differing from that of said fluid; means for applying a potential difference between at least one electrode on said front substrate and at least one electrode on said back substrate, thus developing an electric field between said substrates thereby making at least part of the diaphragm to apply on one of the two substrates in accordance with the direction of said electric field, said incident light being scattered when said diaphragm is applied on said front substrate, and being substantially absorbed by said fluid when said diaphragm is applied on said back substrate.
Claim 2
Dependent Claim 177 words
A display device using electrophoresis, comprising two substrates, a front substrate disposed towards incident light and a back substrate, said substrates carrying electrodes, at least said front substrate and its electrodes being transparent, said substrates being substantially parallel and attached together in order to form a closed vessel filled with a resistive fluid; said display device further comprising a thin electrophoretically displaceable diaphragm arranged in said vessel and permeable to said fluid, said diaphragm being capable of scattering the incident light in a colour differing from that of said fluid; means for applying a potential difference between at least one electrode on said front substrate and at least one electrode on said back substrate, thus developing an electric field between said substrates thereby making at least part of the diaphragm to apply on one of the two substrates in accordance with the direction of said electric field, said incident light being scattered when said diaphragm is applied on said front substrate, and being substantially absorbed by said fluid when said diaphragm is applied on said back substrate.
Claim 3
Dependent Claim 22 words
A device according to claim 1, wherein said diaphragm is arranged freely in said vessel, and is constituted by a rigid material.
Claim 4
Dependent Claim 23 words
A device according to claim 1, wherein said front substrate carries a plurality of electrodes which can be controlled independently of each other.
Claim 5
Dependent Claim 27 words
A device according to claim 3, wherein said plurality of electrodes is a matrix of electrodes having substantially identical shapes, arranged in accordance with rows and columns.
Claim 6
Dependent Claim 27 words
A device according to claim 3, wherein said front substrate carries electrodes of elongated shape, or segments, whose graphic combination is capable of forming an alphanumerical character.
Claim 7
Dependent Claim 42 words
A device according to claim 3, wherein said diaphragm comprises a plurality of semi-free elements constituted by a partial cutting out of said diaphragm, said elements being located opposite said electrodes and each of said semi-free elements constituting an information display zone.
Claim 8
Dependent Claim 15 words
A device according to claim 6, wherein said diaphragm is fixed to said back substrate.
Claim 9
Dependent Claim 23 words
A device according to claim 6, further comprising at least one electrically insulating plate arranged between said diaphragm and one of said substrates.
Claim 10
Dependent Claim 39 words
A device according to claim 3, wherein said diaphragm is attached around the whole of its periphery so that it is parallel to said substrates and out of contact therewith, and is constituted by an elastic and deformable material.
Claim 11
Dependent Claim 54 words
A device according to claim 5, wherein said diaphragm is constituted by a plurality of segments of substantially the same shape and size as said electrodes, said device further comprising a thick electrically insulating plate located between the two substrates opposite said electrodes, said segments being located freely in opening formed in said plate.
Claim 12
Dependent Claim 29 words
A device according to claim 1, wherein said diaphragm comprises a plurality of passages in the material of which it is made, thus achieving the permeability of said diaphragm.
Claim 13
Dependent Claim 18 words
A device according to claim 1, wherein said diaphragm has a density close to that of said fluid.
Claim 14
Dependent Claim 16 words
A device according to claim 1, wherein said diaphragm is constituted by a woven fibre material.
Claim 15
Dependent Claim 24 words
A device according to claim 1, wherein said diaphragm is constituted by a plastic material comprising a pigment capable of scattering the incident light.

References Cited (Backward Citations)

US3303488A Cited
US3376092A Cited
US3892568A Cited
US3909116A Cited
US3812490A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1980-12-05 1981-06-06 1981-12-06 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1984-12-05 1985-06-06 1985-12-06 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1988-12-05 1989-06-06 1989-12-06 $7700.00 Window Closed / Lapsed

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