Patent US4821115A successfully refreshed from Google Patents.
US4821115A
Expired / Lapsed
US
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Color hard copy apparatus having simplified analog-to-digital conversion with adjustable threshold levels
Assignee: Seiko Instruments Inc
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Filing: 1986-09-30
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Granted: 1989-04-11
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Expires: 2006-09-30
Abstract
Abstract A color hard copy apparatus converts an analog video signal of a still picture frame displayed on a color graphic display into binary video data to obtain a multicolor gradation picture. A single analog-to-digital converter samples the analog video signal a plurality of times at respectively different threshold levels, each threshold level being maintained constant during the sampling of the entire picture frame, to convert the analog video signal into corresponding binary video data. The binary video data are written in a picture memory at predetermined write-in addresses according to a predetermined multicolor gradation picture program, such as an organized dither program or a density pattern, and the binary video data are read out of the picture memory according to the predetermined multicolor gradation picture program to obtain binary picture data signals for use in printing a high-quality multicolor gradation picture corresponding to the desired picture frame displayed on the color graphic display.
Inventors
- 👤 Kenichi Matsushima
- 👤 Fumihiro Tanaka
- 👤 Kaneo Yamaguchi
- 👤 Yoshio Shimada
- 👤 Shinya Watanabe
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 20:22
CPC Classifications
H; H04; H04N; H04N1/00; H04N1/46; H04N1/52; H04N1/40; H04N1/405; H04N1/4051
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
196 words
In a color hard copy apparatus which converts an analog video signal of a still picture frame displayed on a color graphic display into binary video data to obtain a multicolor gradation picture: analog-to-digital converting means for sampling an analog video signal having R(red), G(green) and B(blue) signal components representative of a desired picture frame displayed on a color graphic display and converting the analog video signal into corresponding binary video data, the analog-to-digital converting means comprising a single analog-to-digital converter having an adjustably settable threshold level, and means for adjustably setting the threshold level of the analog-to-digital converter to a plurality of different constant threshold levels such that the analog video signal of the entire picture frame is sampled at each different constant threshold level; means for writing the binary video data in a picture memory at predetermined write-in addresses according to a predetermined multicolor gradation picture program; and means for reading the binary video data out of the picture memory according to the predetermined multicolor gradation picture program to obtain binary picture data signals for use in printing a multicolor gradation picture corresponding to the desired picture frame displayed on the color graphic display.
Claim 2
Dependent Claim
196 words
In a color hard copy apparatus which converts an analog video signal of a still picture frame displayed on a color graphic display into binary video data to obtain a multicolor gradation picture: analog-to-digital converting means for sampling an analog video signal having R(red), G(green) and B(blue) signal components representative of a desired picture frame displayed on a color graphic display and converting the analog video signal into corresponding binary video data, the analog-to-digital converting means comprising a single analog-to-digital converter having an adjustably settable threshold level, and means for adjustably setting the threshold level of the analog-to-digital converter to a plurality of different constant threshold levels such that the analog video signal of the entire picture frame is sampled at each different constant threshold level; means for writing the binary video data in a picture memory at predetermined write-in addresses according to a predetermined multicolor gradation picture program; and means for reading the binary video data out of the picture memory according to the predetermined multicolor gradation picture program to obtain binary picture data signals for use in printing a multicolor gradation picture corresponding to the desired picture frame displayed on the color graphic display.
Claim 3
Dependent Claim
56 words
A color hard copy apparatus according to claim 1; wherein the analog-to-digital converting means includes means for successively changing the threshold level at which the analog video signal is sampled after completion of the sampling of the entire picture frame at the preceding threshold level until the analog video signal is sampled said plurality of times.
Claim 4
Dependent Claim
35 words
A color hard copy apparatus according to claim 1; wherein the means for writing comprises means for successively writing the binary video data obtained at each threshold level in the picture memory one by one.
Claim 5
Dependent Claim
21 words
A color hard copy apparatus according to claim 1; wherein the predetermined multicolor gradation picture program comprises a density pattern program.
Claim 6
Dependent Claim
20 words
A color hard copy apparatus according to claim 1; wherein the predetermined multicolor gradation program comprises an organized dither program.
References Cited (Backward Citations)
US4238768A
Cited
US4214277A
Cited
US4496987A
Cited
US4449150A
Cited
US4504115A
Cited
US4475127A
Cited
US4495522A
Cited
US4485408A
Cited
US4553173A
Cited
US4554594A
Cited
US4556918A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1992-04-10 | 1992-10-10 | 1993-04-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-04-10 | 1996-10-10 | 1997-04-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-04-10 | 2000-10-10 | 2001-04-11 | $7700.00 | Window Closed / Lapsed |