Background reduction
AssigneeXerox Corporation
InventorsChristopher Snelling, William S. Little, Robert H. Townsend
Life of this patent
Estimating the term…
Abstract
Photoelectrophoretic imaging system having an additional electrode for subjecting a film of photoelectrophoretic imaging suspension to an electric field at a potential above the corona threshold of the film prior to image exposure. The effect of the electric field and resulting current causes electrophoretic deposition of the imaging particles in the imaging suspension in a uniform layer to thereby eliminate or reduce background degradation in the final image formed.
Claims12
A photoelectrophoretic imaging apparatus comprising in combination:
- a. an optically transparent first electrode having a surface capable of supporting a layer of imaging suspension thereon;
- b. means for introducing a layer of imaging suspension to the surface of said first electrode;
- c. a second electrode mounted in close proximity to said first electrode so as to make contact with a surface of a layer of imaging suspension carried on said first electrode surface thereby defining a nip having an air gap on each side thereof;
- d. means to apply a first potential difference across a layer of imaging suspension carried on said first electrode surface between said first electrode and said second electrode;
- e. a third electrode mounted in close proximity to said first electrode so as to make contact with a surface of a layer of imaging suspension carried on said first electrode surface thereby defining a nip having an air gap on each side thereof;
- f. means to expose with actinic electromagnetic radiation of an image to be reproduced, that portion of a layer of imaging suspension at an area of closest proximity of said third electrode and said first electrode;
- g. means to apply a second potential difference across a layer of imaging suspension carried on said first electrode surface, between said third electrode and said first electrode during said exposure;
- and
- h. means to cause relative movement between said first electrode and said second and third electrodes.
A photoelectrophoretic imaging apparatus comprising in combination:
- a. an optically transparent, flat plate, first electrode having a surface capable of supporting a layer of imaging suspension thereon;
- b. means for introducing a layer of imaging suspension to the surface of said first electrode;
- c. a second electrode mounted in close proximity to said first electrode such that said second electrode can make progressively advancing contact with a surface of a layer of imaging suspension carried on the surface of said first electrode;
- d. means to apply a first potential difference across a layer of imaging suspension carried on said first electrode surface, between said first electrode and said second electrode;
- e. a third electrode mounted in close proximity to said first electrode such that said third electrode can make progressively advancing contact with a surface of a layer of imaging suspension carried on said first electrode;
- f. means to expose with actinic electromagnetic radiation of an image to be reproduced, that portion of a layer of imaging suspension carried on said first electrode at an area of contact of said third electrode and said first electrode;
- g. means to apply a second potential difference across a layer of imaging suspension carried on said first electrode between said third electrode and said first electrode during said exposure;
- and
- h. means to cause relative movement between said first electrode and said second and third electrodes.
Dependencies are inferred from the claim text.