Method and apparatus for improving contrast in electrophoretic display
AssigneeXonics, Inc.
InventorsJohn H. Lewis, Michael D. McDiarmid
Life of this patent
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Abstract
Apparatus and method for improving contrast in the visual image formed by toner deposited on an electrostatic image such as is formed in electronradiography. Electrophoretic toner particles and a dye are dispersed in a liquid, with the particles being deposited onto a substrate which carries the electrostatic image, with the selectively attracted particles forming the visual image. The visual image is viewed by reflected or scattered light with the light having a color emission spectrum substantially corresponding to the absorption spectrum of the dye for absorbing and thereby eliminating unwanted light.
Claims15
In an electronradiography imaging chamber for providing a visual image, the combination of:
- first and second electrodes;
- means for supporting said electrodes in spaced relation with a gap therebetween;
- an X-ray absorber and electron and positive ion emitter in said gap, with X-ray radiation entering said gap being absorbed and providing electrons and positive ions in said gap;
- a plurality of electrophoretic particles dispersed in a liquid in said gap;
- a dye dispersed in said liquid, said dispersed dye having a color absorption spectrum;
- means for connecting an electrical potential across said electrodes for attracting electrons toward one electrode and positive ions toward the other depending upon the polarity of the power source and forming an electrostatic charge image, with said particles being selectively deposited as a function of said electrostatic charge image forming a visual image viewable through one of said electrodes;
- and
- means for directing illumination onto deposited particles, with said illumination having a color emission spectrum substantially corresponding to said dye absorption spectrum.
Dependencies are inferred from the claim text.