Patent US3667110A successfully refreshed from Google Patents.
Patent US5708464A successfully refreshed from Google Patents.
US5708464A
Expired / Lapsed
US
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Device for direct electrostatic printing (DEP) with "previous correction"
Assignee: Agfa Gevaert NV
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Filing: 1996-11-04
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Granted: 1998-01-13
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Expires: 2016-11-04
Abstract
Abstract A DEP device adapted for grey-scale printing comprising a back electrode (105), a printhead structure (106), an array of printing apertures (107) in the printhead structure (106) through which a particle flow can be electrically modulated by a control electrode (106a), a toner delivery means (101), at least one control means (111) for applying an electric field to the control electrodes, wherein: (i) the control means controls each single control electrode to enable the printing through each single printing aperture (107) of pixel dots (PD), each of the pixel dots intended to have a density D, and (ii) the control means controls the printing of the pixel dots through the each single printing aperture as a function of both the intended density (D intend ) and the density (D prev ) previously produced through the single printing aperture, i.e. the control means use "previous correction".
Inventors
- 👤 Guido Desie
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 16:49
CPC Classifications
B; B41; B41J; B41J2/00; B41J2/385; B41J2/41; B41J2/415; B41J2/4155; G; G03; G03G; G03G15/00; G03G15/22; G03G15/34; G03G15/344; G03G15/346; G03G2217/00; G03G2217/0008; G03G2217/0025
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
107 words
A DEP device adapted for grey-scale printing comprising: a back electrode(105), a printhead structure(106), an array of printing apertures(107) in said printhead structure(106) through which a particle flow can be electrically modulated by a control electrode(106a), a toner delivery means(101), at least one control means(111) for applying an electric field to said control electrodes, wherein: (i) said control means controls each single control electrode to enable the printing of pixel dots through each single printing aperture(107) each of said pixel dots intended to have a predetermined density, and, (ii) said control means controls said printing of said pixel dots using previous electrode parameter characteristics as correction data.
Claim 2
Dependent Claim
107 words
A DEP device adapted for grey-scale printing comprising: a back electrode(105), a printhead structure(106), an array of printing apertures(107) in said printhead structure(106) through which a particle flow can be electrically modulated by a control electrode(106a), a toner delivery means(101), at least one control means(111) for applying an electric field to said control electrodes, wherein: (i) said control means controls each single control electrode to enable the printing of pixel dots through each single printing aperture(107) each of said pixel dots intended to have a predetermined density, and, (ii) said control means controls said printing of said pixel dots using previous electrode parameter characteristics as correction data.
Claim 3
Dependent Claim
113 words
A DEP device according to claim 1, wherein said grey-printing is controlled by said control means by voltage modulation of electrical fields applied to said control electrodes according to the following formula: V3real=V3intend+(V3prev×Kv) wherein, V3real is the value of the real blocking voltage V3 at time LTn; V3intend is the value of the blocking voltage V3 to be used at time LTn when previous correction data is not applied; V3prev is the value of V3 at time LTn-1; Kv is a correction constant that is smaller than 1; LTn is a line time interval used to print an nth line; and, LTn-1 is a line time interval used to print the n-1th line.
Claim 4
Dependent Claim
11 words
A DEP device according to claim 2, wherein K v ≦0.20.
Claim 5
Dependent Claim
127 words
A DEP device according to claim 1, wherein said grey-scale printing is controlled by said control means by time modulation of electrical fields applied to said control electrodes according to the following formula: WRTreal=WRTintend-((LT-WRTprev)×Kt) wherein, WRTreal is the real value of the write time interval used at time LTn; WRTintend is the value of the write time interval to be used at time LTn when previous correction data is not applied; WRTprev is the value of the write time interval at LTn-1; Kt is a correction constant that is smaller than 1; LTn is the line time interval used to print an nth line; LTn-1 is the line time interval used to print the n-1th line; and, LT is the line time interval for printing a line.
Claim 6
Dependent Claim
29 words
A DEP device according to claim 1, wherein said correction data takes into account the electrical field used to print the density of more than one previous image dot.
Claim 7
Dependent Claim
20 words
A DEP device according to claim 1, wherein said correction data is combined with correction data of neighboring image dots.
References Cited (Backward Citations)
US4860036A
Cited
US5040004A
Cited
US5136311A
Cited
US5483273A
Cited
US5377159A
Cited
US5214451A
Cited
US5625399A
Cited
US5400062A
Cited
US5404155A
Cited
US5644351A
Cited
US5546113A
Cited
US5631679A
Cited
US5633110A
Cited
US5614932A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2001-01-12 | 2001-07-14 | 2002-01-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2005-01-12 | 2005-07-14 | 2006-01-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2009-01-12 | 2009-07-14 | 2010-01-13 | $7700.00 | Window Closed / Lapsed |