US3977007A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Gray tone generation
Assignee: AT&T Teletype Corp
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Filing: 1975-06-02
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Granted: 1976-08-24
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Expires: 1995-06-02
Abstract
Abstract An ink jet printer in which refined half-tones or shades of gray are produced while retaining high contrast capability using a dot matrix in which the dots are of the same density for the same shading plus or minus one drop of ink at selected dot locations within the matrix but with each dot being printed in response to an individual shading density or darkness input signal.
Inventors
- 👤 James M. Berry
- 👤 Anthony J. Hauser
- 👤 Kurt E. Knuth
- 👤 Gary B. Ollendick
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 01:38
CPC Classifications
H; H04; H04N; H04N1/00; H04N1/40; H04N1/40087; B; B41; B41J; B41J2/00; B41J2/005; B41J2/01; B41J2/205; B41J2/2054; H04N1/40025; H04N1/40043; H04N1/405; H04N1/4051; B41J2/17; B41J2/18; B41J2/185
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
94 words
A method of refining a gray shade image produced with a liquid ink-jet recorder that projects discrete drops of ink onto a record divided into matrix cells, each matrix cell including a plurality of dot locations; depositing enough drops of liquid ink at each dot location of a matrix cell to produce approximately the requisite shade for that dot location within the matrix cell; and selectively adjusting the number of drops deposited at a dot location of the matrix cell area to refine the approximation to a more accurate half-tone representation of the image.
Claim 2
Independent Claim
94 words
A method of refining a gray shade image produced with a liquid ink-jet recorder that projects discrete drops of ink onto a record divided into matrix cells, each matrix cell including a plurality of dot locations; depositing enough drops of liquid ink at each dot location of a matrix cell to produce approximately the requisite shade for that dot location within the matrix cell; and selectively adjusting the number of drops deposited at a dot location of the matrix cell area to refine the approximation to a more accurate half-tone representation of the image.
Claim 3
Dependent Claim
103 words
In an ink jet device for recording dots on a record, apparatus for forming images having shades of gray, comprising: means for causing the recording device to deposit at a predetermined dot location in a matrix cell on the record a number of drops of ink substantially representative of the shade to be recorded at the matrix cell location; and means responsive to the location of the predetermined dot within the matrix cell for selectively adjusting, by one, the number of drops of ink deposited at the predetermined dot location so as to refine the density of the image recorded on the record.
Claim 4
Dependent Claim
103 words
In an ink jet device for recording dots on a record, apparatus for forming images having shades of gray, comprising: means for causing the recording device to deposit at a predetermined dot location in a matrix cell on the record a number of drops of ink substantially representative of the shade to be recorded at the matrix cell location; and means responsive to the location of the predetermined dot within the matrix cell for selectively adjusting, by one, the number of drops of ink deposited at the predetermined dot location so as to refine the density of the image recorded on the record.
Claim 5
Dependent Claim
27 words
An apparatus according to claim 2 wherein the causing means causes the recording device to deposit the minimum number of drops to produce the shade of gray.
Claim 6
Dependent Claim
28 words
An apparatus according to claim 3 wherein the adjusting means adjusts by selectively increasing by one the number of drops of ink deposited at a given dot location.
Claim 7
Dependent Claim
37 words
An apparatus according to claim 4 wherein the selective increase is dependent upon the shade of gray to be reproduced at the dot location of the matrix and the position of the dot location within the matrix.
Claim 8
Dependent Claim
48 words
An apparatus according to claim 2 wherein the number of drops of ink caused to be deposited at a dot location within a matrix cell is sufficient, except for the operation of the adjusting means, to produce a shade no darker than the shade of the dot location.
Claim 9
Dependent Claim
96 words
An ink jet device for recording dots on a record, including apparatus for matrix-forming images having shades of gray, comprising: means for depositing at each dot location of a matrix of dot locations a number of drops of ink to produce a shading no lighter than the shading of that dot location within its associated matrix cell; and means for selectively depositing an additional drop of ink at selected matrix cell dot locations to darken the cell no more than the darkness produced by an additional drop of ink at all dot locations of the cell.
Claim 10
Dependent Claim
96 words
An ink jet device for recording dots on a record, including apparatus for matrix-forming images having shades of gray, comprising: means for depositing at each dot location of a matrix of dot locations a number of drops of ink to produce a shading no lighter than the shading of that dot location within its associated matrix cell; and means for selectively depositing an additional drop of ink at selected matrix cell dot locations to darken the cell no more than the darkness produced by an additional drop of ink at all dot locations of the cell.
Claim 11
Dependent Claim
27 words
An apparatus according to claim 2 wherein the causing means causes the recording device to deposit the maximum number of drops to produce the shade of gray.
Claim 12
Dependent Claim
28 words
An apparatus according to claim 8 wherein the adjusting means adjusts by selectively decreasing by one the number of drops of ink deposited at a given dot location.
Claim 13
Dependent Claim
37 words
An apparatus according to claim 9 wherein the selective decrease is dependent upon the shade of gray to be reproduced at the dot location of the matrix and the position of the dot location within the matrix.
Claim 14
Dependent Claim
48 words
An apparatus according to claim 2 wherein the number of drops of ink caused to be deposited at a dot location within a matrix cell is sufficient, except for the operation of the adjusting means, to produce a shade no lighter than the shade of the dot location.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1979-08-24 | 1980-02-23 | 1980-08-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-08-24 | 1984-02-23 | 1984-08-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-08-24 | 1988-02-23 | 1988-08-24 | $7700.00 | Window Closed / Lapsed |