US4526441A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method and electrolytic display for selectively displaying an image
Assignee: International Business Machines Corp
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Filing: 1982-05-07
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Granted: 1985-07-02
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Expires: 2002-05-07
Abstract
Abstract An image is displayed in an electrolytic display by the reversible deposition on electrodes having non-scattering surfaces of a deposit having light scattering properties. The deposit scatters incident light out of the specular direction and the image is formed from one only of the specular and non-specular components of the emergent light.
Inventors
- 👤 Barry F. Dowden
- 👤 Donald J. Barclay
- 👤 David H. Kirkman
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 09:32
CPC Classifications
G; G09; G09G; G09G3/00; G09G3/20; G09G3/34; G09G3/38; G02; G02F; G02F1/00; G02F1/01; G02F1/15; G02F1/1503; G02F1/1506; G02F1/153; G02F1/157; G09G2300/00; G09G2300/08
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
67 words
A method of selectively displaying an image comprising the steps of: writing the display by reversibly electrodepositing a light scattering deposit on a substantially non-scattering opaque surface in the desired image configuration, illuminating the display in reflection from a particular direction, whereby incident light is scattered out of the specular direction by written areas; and projecting a non-specular component of the emergent light to form the image.
Claim 2
Independent Claim
67 words
A method of selectively displaying an image comprising the steps of: writing the display by reversibly electrodepositing a light scattering deposit on a substantially non-scattering opaque surface in the desired image configuration, illuminating the display in reflection from a particular direction, whereby incident light is scattered out of the specular direction by written areas; and projecting a non-specular component of the emergent light to form the image.
Claim 3
Dependent Claim
45 words
A method according to claim 1 including projecting said non-specular component with a lens whose optical axis intersects the surface and illuminating the display obliquely in such a manner that any specularly reflected light from the surface falls outside the entrance pupil of the lens.
Claim 4
Dependent Claim
34 words
A method according to claim 2 in which the electro-deposited material is a viologen and in which the step of writing the display comprises depositing between 0.5 and 1.0 mCcm -2 equivalent of viologen.
Claim 5
Dependent Claim
38 words
A method according to claim 2 in which the step of writing the display further comprises passing a constant current of density substantially equal to 0.5 mAcm -2 to the areas of the surface where deposition is required.
Claim 6
Dependent Claim
107 words
An electrolytic display for selectively displaying an image comprising: a plurality of display electrodes having substantially non-scattering opaque surfaces; an electrolyte containing a reversibly depositable material in solution; display writing means for electrically energizing selected electrodes to cause the deposition thereon of said material in the desired image configuration; the deposited material having light scattering properties; and an optical system comprising: illumination means for illuminating the display electrodes in reflection from a particular direction, whereby incident light is scattered out of the specular direction by the deposit on the energized electrodes; and projection means for projecting the non-specular component of the emergent light to form the image.
Claim 7
Dependent Claim
107 words
An electrolytic display for selectively displaying an image comprising: a plurality of display electrodes having substantially non-scattering opaque surfaces; an electrolyte containing a reversibly depositable material in solution; display writing means for electrically energizing selected electrodes to cause the deposition thereon of said material in the desired image configuration; the deposited material having light scattering properties; and an optical system comprising: illumination means for illuminating the display electrodes in reflection from a particular direction, whereby incident light is scattered out of the specular direction by the deposit on the energized electrodes; and projection means for projecting the non-specular component of the emergent light to form the image.
Claim 8
Dependent Claim
28 words
A display according to claim 4 in which the surfaces of the electrodes are of bright metal so that incident light is substantially specularly reflected from the electrodes.
Claim 9
Dependent Claim
67 words
A display according to claim 5 in which the projection means includes a lens assembly whose optical axis intersects the display area defined by the plurality of electrodes and the illumination means includes a partially collimated light source and is arranged to illuminate the display area obliquely such that any specularly reflected light from the display electrodes falls outside the entrance pupil of said projection lens assembly.
Claim 10
Dependent Claim
20 words
A display according to claim 5 in which the material is a viologen and the display electrodes are of gold.
Claim 11
Dependent Claim
18 words
A display according to claim 8 in which the material is a mixture of 1,1'di-n-heptyl4,4'bipyridinium phosphate and hypophosphite.
References Cited (Backward Citations)
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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) | 1988-07-01 | 1988-12-31 | 1989-07-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-07-01 | 1992-12-31 | 1993-07-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-07-01 | 1996-12-31 | 1997-07-02 | $7700.00 | Window Closed / Lapsed |