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Patent US6177948B1 successfully refreshed from Google Patents.
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US6177948B1 Expired / Lapsed US ⏱️ 0.0 years remaining

PQE for font vs. large dark patch

Assignee: Ricoh Co Ltd
•
Filing: 1998-03-23
•
Granted: 2001-01-23
•
Expires: 2018-03-23
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Abstract

Abstract An electrophotographic apparatus and method are provided to reduce smearing on printed medium by reducing the toner pile height of printed lines and characters. Control is provided for establishing the amount of toner to be applied on a picture element (PEL) basis. This is accomplished by the creation of mask patterns that distinguish characters and lines from large patches to be printed, and by identifying PELs internal of characters boundary requiring exposure modulation during printing.

Inventors

  • 👤 Dennis C. Estabrooks
  • 👤 Jack L. Zable

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-09 15:52
CPC Classifications
B; B41; B41J; B41J2/00; B41J2/385; G; G06; G06K; G06K15/00; G06K15/02; G06K15/12; G06K2215/00; G06K2215/0002; G06K2215/0062; G06K2215/0071; G06K2215/0074

Claims Analysis

Total Claims: 25
Claim 1
Independent Claim 124 words
An electrophotographic printer apparatus that reduces smearing of two-dimensional printed images on printed medium, the two-dimensional images comprised of predetermined image pattern generated from data representing either print or blank in a matrix of positions arranged in horizontal rows and vertical columns, the apparatus comprising: a voltage source; a memory for storing the predetermined image pattern data; a program comprising at least one mask matrix, wherein the program performs logical operations to compare the at least one mask matrix with the predetermined image pattern data on a PEL by-PEL basis to determine whether a target PEL is positioned interior of a character or line; and, a controller that modulates the voltage source if the target PEL is positioned interior of a character or line.
Claim 2
Dependent Claim 124 words
An electrophotographic printer apparatus that reduces smearing of two-dimensional printed images on printed medium, the two-dimensional images comprised of predetermined image pattern generated from data representing either print or blank in a matrix of positions arranged in horizontal rows and vertical columns, the apparatus comprising: a voltage source; a memory for storing the predetermined image pattern data; a program comprising at least one mask matrix, wherein the program performs logical operations to compare the at least one mask matrix with the predetermined image pattern data on a PEL by-PEL basis to determine whether a target PEL is positioned interior of a character or line; and, a controller that modulates the voltage source if the target PEL is positioned interior of a character or line.
Claim 3
Dependent Claim 31 words
The electrophotographic printer apparatus of claim 1 further comprising toner applied as a pile on the printed medium, wherein modulation of the voltage source reduces the pile height of the toner.
Claim 4
Dependent Claim 14 words
The electrophotographic printer apparatus of claim 1 wherein said voltage source controls a light.
Claim 5
Dependent Claim 18 words
The electrophotographic printer apparatus of claim 3 wherein the light is a laser or a light emitting diode.
Claim 6
Dependent Claim 73 words
The electrophotographic printer apparatus of claim 1 : wherein the predetermined image pattern data comprises a target PEL and the mask matrix comprises a target PEL overlay; wherein the predetermined image pattern data is compared to the mask matrix with the target PEL being aligned with the target PEL overlay; and, wherein the controller modulates the voltage source at the target PEL if the predetermined image pattern data matches the entire mask matrix.
Claim 7
Dependent Claim 53 words
The electrophotographic printer of claim 1 wherein the predetermined image pattern data comprises character and line images and symmetrical patterns that collectively produce a gray-level image, and wherein the mask matrix distinguishes a PEL that is interior of the character or the line from a PEL that is interior of the gray-level image.
Claim 8
Dependent Claim 16 words
The electrophotographic printer apparatus according to claim 6 wherein the mask matrix comprises an asymmetrical pattern.
Claim 9
Dependent Claim 160 words
An electrophotographic printer apparatus that reduces smearing of two-dimensional printed images on printed medium, the two-dimensional images comprised of predetermined image pattern generated from data representing either print or blank in a matrix of positions arranged in horizontal rows and vertical columns, the apparatus comprising: a voltage source; a memory for storing the predetermined image pattern data; a program comprising at least one mask matrix, wherein the program performs logical operations to compare the at least one mask matrix with the predetermined image pattern data on a PEL by-PEL basis to determine whether a target PEL is positioned interior of a character or line; and, a controller that modulates the voltage source if the target PEL is positioned interior of a character or line, wherein the voltage source controls a light, wherein the light is in circuit communication with a developing station, and wherein modulation of the voltage source reduces the pile height of toner applied to the printed medium.
Claim 10
Dependent Claim 160 words
An electrophotographic printer apparatus that reduces smearing of two-dimensional printed images on printed medium, the two-dimensional images comprised of predetermined image pattern generated from data representing either print or blank in a matrix of positions arranged in horizontal rows and vertical columns, the apparatus comprising: a voltage source; a memory for storing the predetermined image pattern data; a program comprising at least one mask matrix, wherein the program performs logical operations to compare the at least one mask matrix with the predetermined image pattern data on a PEL by-PEL basis to determine whether a target PEL is positioned interior of a character or line; and, a controller that modulates the voltage source if the target PEL is positioned interior of a character or line, wherein the voltage source controls a light, wherein the light is in circuit communication with a developing station, and wherein modulation of the voltage source reduces the pile height of toner applied to the printed medium.
Claim 11
Dependent Claim 161 words
An electrophotographic printer apparatus that reduces smearing of two-dimensional printed images on printed medium, the two-dimensional images comprised of predetermined image pattern generated from data representing either print or blank in a matrix of positions arranged in horizontal rows and vertical columns, the apparatus comprising: a voltage source; a memory for storing the predetermined image pattern data; a program comprising at least one mask matrix, wherein the program performs logical operations to compare the at least one mask matrix with the predetermined image pattern data on a PEL by-PEL basis to determine whether a target PEL is positioned interior of a character or line; and, a controller that modulates the voltage source if the target PEL is positioned interior of a character or line, wherein the voltage source controls a light, wherein the light is in circuit communication with a drum charging station, and wherein modulation of the voltage source reduces the pile height of toner applied to the printed medium.
Claim 12
Dependent Claim 161 words
An electrophotographic printer apparatus that reduces smearing of two-dimensional printed images on printed medium, the two-dimensional images comprised of predetermined image pattern generated from data representing either print or blank in a matrix of positions arranged in horizontal rows and vertical columns, the apparatus comprising: a voltage source; a memory for storing the predetermined image pattern data; a program comprising at least one mask matrix, wherein the program performs logical operations to compare the at least one mask matrix with the predetermined image pattern data on a PEL by-PEL basis to determine whether a target PEL is positioned interior of a character or line; and, a controller that modulates the voltage source if the target PEL is positioned interior of a character or line, wherein the voltage source controls a light, wherein the light is in circuit communication with a drum charging station, and wherein modulation of the voltage source reduces the pile height of toner applied to the printed medium.
Claim 13
Independent Claim 88 words
A method of reducing smearing of two dimensional printed images printed by an electrophotographic printer apparatus on printed medium the two-dimensional images comprised of predetermined image pattern data representing either print or a blank in a matrix of positions arranged in horizontal rows and vertical columns, the method comprising: providing a mask matrix; comparing the predetermined image pattern data with the mask matrix on a PEL-by-PEL basis; and, modulating a voltage source at a target PEL if the target PEL is positioned interior of a character or line.
Claim 14
Independent Claim 88 words
A method of reducing smearing of two dimensional printed images printed by an electrophotographic printer apparatus on printed medium the two-dimensional images comprised of predetermined image pattern data representing either print or a blank in a matrix of positions arranged in horizontal rows and vertical columns, the method comprising: providing a mask matrix; comparing the predetermined image pattern data with the mask matrix on a PEL-by-PEL basis; and, modulating a voltage source at a target PEL if the target PEL is positioned interior of a character or line.
Claim 15
Dependent Claim 28 words
The method of claim 10 further comprising: providing toner applied in a pile on the printed medium, wherein modulating the voltage source reduces the pile height of toner.
Claim 16
Dependent Claim 12 words
The method of claim 10 wherein the voltage source controls a light.
Claim 17
Dependent Claim 16 words
The method of claim 10 wherein the light is a laser or a light emitting diode.
Claim 18
Dependent Claim 70 words
The method of claim 10 wherein the predetermined image pattern data comprises a target PEL and the mask matrix comprises a target PEL overlay, wherein the predetermined image pattern data is compared to the mask matrix with the target PEL being aligned with the target PEL overlay; and, wherein the controller modulates the voltage source at the target PEL if the predetermined image pattern data matches the entire mask matrix.
Claim 19
Dependent Claim 51 words
The method of claim 10 wherein the predetermined image pattern data comprises character and line images and symmetrical patterns that collectively produce a gray-level image, and wherein the mask matrix distinguishes a PEL that is interior of the character or line from a PEL that is interior of the gray-level image.
Claim 20
Dependent Claim 14 words
The method according to claim 15 wherein the mask matrix comprises an asymmetrical pattern.
Claim 21
Dependent Claim 42 words
The method according to claim 16 wherein the, and the predetermined image pattern data is compared with the mask matrix in a first position, and is then compared with the mask matrix rotated to a second position 90° from the first position.
Claim 22
Independent Claim 130 words
A method of reducing smearing of two dimensional printed images printed by an electrophotographic printer apparatus on printed medium, the two-dimensional images comprised of predetermined image pattern data representing either print or a blank in a matrix of positions arranged in horizontal rows and vertical columns, the method comprising: providing a mask matrix; comparing the predetermined image pattern data with the mask matrix on a PEL-by-PEL basis; modulating a voltage source at a target PEL if the target PEL is positioned interior of a character or line, and applying toner in a pile on the printed medium, wherein the voltage source controls a light, wherein the light is in circuit communication with a developing station, and wherein modulation of the voltage source reduces the pile height of the applied toner.
Claim 23
Independent Claim 130 words
A method of reducing smearing of two dimensional printed images printed by an electrophotographic printer apparatus on printed medium, the two-dimensional images comprised of predetermined image pattern data representing either print or a blank in a matrix of positions arranged in horizontal rows and vertical columns, the method comprising: providing a mask matrix; comparing the predetermined image pattern data with the mask matrix on a PEL-by-PEL basis; modulating a voltage source at a target PEL if the target PEL is positioned interior of a character or line, and applying toner in a pile on the printed medium, wherein the voltage source controls a light, wherein the light is in circuit communication with a developing station, and wherein modulation of the voltage source reduces the pile height of the applied toner.
Claim 24
Independent Claim 130 words
A method of reducing smearing of two dimensional printed images printed by an electrophotographic printer apparatus on printed medium, the two-dimensional images comprised of predetermined image pattern data representing either print or a blank in a matrix of positions arranged in horizontal rows and vertical columns, the method comprising: providing a mask matrix; comparing the predetermined image pattern data with the mask matrix on a PEL-by-PEL basis; and, modulating a voltage source at a target PEL if the target PEL is positioned interior of a character or line; and applying toner in a pile on the printed medium, wherein the voltage source controls a light, wherein the light is in circuit communication with a drum charging station, and wherein modulation of the voltage source reduces the pile height of toner.
Claim 25
Independent Claim 130 words
A method of reducing smearing of two dimensional printed images printed by an electrophotographic printer apparatus on printed medium, the two-dimensional images comprised of predetermined image pattern data representing either print or a blank in a matrix of positions arranged in horizontal rows and vertical columns, the method comprising: providing a mask matrix; comparing the predetermined image pattern data with the mask matrix on a PEL-by-PEL basis; and, modulating a voltage source at a target PEL if the target PEL is positioned interior of a character or line; and applying toner in a pile on the printed medium, wherein the voltage source controls a light, wherein the light is in circuit communication with a drum charging station, and wherein modulation of the voltage source reduces the pile height of toner.

References Cited (Backward Citations)

US4460909A Cited
US4403257A Cited
US4882252A Cited
US4967211A Cited
US5357583A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 2004-01-23 2004-07-24 2005-01-23 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2008-01-23 2008-07-24 2009-01-23 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2012-01-23 2012-07-24 2013-01-23 $7700.00 Window Closed / Lapsed

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