EP0933752A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Poled electrets for Gyricon-based electric-paper displays
Assignee: Xerox Corp
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Filing: 1999-01-25
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Granted: —
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Expires: 2019-01-25
Abstract
Abstract Twisting balls (10) for an electric-paper display are formed from a polarizable material and encapsulated in a protective shell (12). The balls (10) are disposed between first and second electrodes (14, 16) which generate an electric field. The electric field polarizes each ball (10) transforming each into a dipole electret having a first and second charged poles. At least one colorant (20) is applied to each of the balls (10) to obtain multichromal balls such that the charged poles are distinct from each other. The polarized multichromal balls may then be used in fabricating an electric-paper display by encapsulating the balls (10) in an array such that each ball is capable of rotating in response to a selectively applied electric field.
Inventors
- 👤 James C. Mikkelsen Jr.
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-07 12:24
CPC Classifications
G; G02; G02B; G02B26/00; G02B26/02; G02B26/026; G09; G09F; G09F9/00; G09F9/30; G09F9/37; G09F9/372
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
119 words
A method of forming an electric paper display comprising the steps of; forming monochromal balls from a polarizable material; encapsulating each of the monochromal balls in a shell; polarizing the monochromal balls by applying a first electric field thereto such
that each ball forms a positive hemisphere and a negative hemisphere; applying at least one colorant to each of the monochromal balls to obtain
multichromal balls such that the positive hemispheres of each ball carry a colorant
distinct from the negative hemispheres; and fabricating an electric paper display by encapsulating the multichromal balls in
an array such that each multichromal ball is capable of rotating to display a colorant in
response to a second electric field selectively applied thereto.
Claim 2
Dependent Claim
49 words
The method as set forth in claim 1 further including; before the polarizing step, heating the monochromal balls such that the
polarizable material attains a state of increased conductivity; and after the polarizing step, cooling the monochromal balls such that the
polarizable material attains a state of low conductivity.
Claim 3
Dependent Claim
50 words
The method as set forth in claim 1 wherein the polarizing includes; providing two electrodes for generating an electric field therebetween; and positioning the monochromal balls between the two electrodes and exposing the
monochromal balls to the electric field for a sufficient time to polarize each of the
monochromal balls.
Claim 4
Dependent Claim
21 words
The method as set forth in claim 3 further includes surrounding the
monochromal balls in a dielectric fluid to prevent arcing.
Claim 5
Dependent Claim
42 words
The method as set forth in claim 1 wherein the applying at least one
colorant includes applying a charged pigment to each ball such that the charged pigment
migrates to one area of each ball in accordance with the first electric field.
Claim 6
Dependent Claim
39 words
The method as set forth in claim 1 wherein the fabricating includes
providing a panel having an array of cavities, each of the cavities containing one
multichromal ball such that the one multichromal ball is capable of rotating therein.
Claim 7
Dependent Claim
25 words
The method as set forth in claim 1 wherein the shell is formed as a sheet
which collectively encapsulates a plurality of the monochromal balls.
Claim 8
Independent Claim
99 words
A method of forming multichromal balls for an electric paper display
comprising the steps of: forming a plurality of balls from a core material; encapsulating each of the plurality of balls in a shell; transforming the core material of each of the plurality of balls into a dipole
electret having a first charged pole and a second charged pole, the first charged pole
being differently charged than the second charged pole; and forming multichromal balls by coloring each of the plurality of balls such that
the first charged pole of each ball is distinct from the second charged pole.
Claim 9
Dependent Claim
72 words
The method as set forth in claim 8 further including, after the
encapsulating step: adhering the plurality of balls to a substrate; heating the plurality of balls to a fluid state; providing two electrodes for generating an electric field therebetween; positioning the substrate and the plurality of balls between the two electrodes,
the plurality of balls being polarized by the electric field; and cooling the plurality of balls to a solid state.
Claim 10
Dependent Claim
22 words
The method as set forth in claim 8 wherein the forming of the plurality of
balls includes atomizing a fluid into droplets.
References Cited (Backward Citations)
No citation records indexed.
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