US4773734A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of forming halftone screen
Assignee: Fujifilm Holdings Corp
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Filing: 1987-02-13
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Granted: 1988-09-27
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Expires: 2007-02-13
Abstract
Abstract A halftone dot image is produced by superposing image information produced by scanning an original on a halftone screen composed of a plurality of scanning lines constituted by electrically generated halftone screen signals and arranged side by side in a direction normal to a scanning direction in which the scanning lines extend. Each of dots of the halftone screen is formed with an integral number of scanning lines commensurate with a screen angle of the halftone screen. The halftone screen signals are equalized in level at mutually corresponding areas in the respective dots.
Inventors
- 👤 Masahiro Inoda
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 08:10
CPC Classifications
H; H04; H04N; H04N1/00; H04N1/40; H04N1/405; H04N1/4055; H04N1/4058; Y; Y10; Y10S; Y10S359/00; Y10S359/90
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
176 words
A method for forming a halftone screen in producing a halftone dot image by superposing image information produced by scanning an original on the halftone screen composed of a plurality of scanning lines constituted by electrically generated halftone screen signals and arranged side by side in a direction normal to a scanning direction in which the scanning lines extend, said method comprising the steps of: forming each dot of said halftone screen with an integral number of scanning lines commensurate with a screen angle of the halftone screeen; and equalizing the halftone screen signals in level at mutually corresponding areas in the respective dots; wherein the halftone screen is composed of a repeated pattern of minimum basic periodic portions, the number α of scanning lines which constitute each of said basic periodic portions being selected on the following equation: ##EQU6## where θ is the screen angle, β is the number of scanning lines disposed between closest vertexes of a square dot with respect to said direction normal to the scanning direction, and m is an integer.
Claim 2
Independent Claim
176 words
A method for forming a halftone screen in producing a halftone dot image by superposing image information produced by scanning an original on the halftone screen composed of a plurality of scanning lines constituted by electrically generated halftone screen signals and arranged side by side in a direction normal to a scanning direction in which the scanning lines extend, said method comprising the steps of: forming each dot of said halftone screen with an integral number of scanning lines commensurate with a screen angle of the halftone screeen; and equalizing the halftone screen signals in level at mutually corresponding areas in the respective dots; wherein the halftone screen is composed of a repeated pattern of minimum basic periodic portions, the number α of scanning lines which constitute each of said basic periodic portions being selected on the following equation: ##EQU6## where θ is the screen angle, β is the number of scanning lines disposed between closest vertexes of a square dot with respect to said direction normal to the scanning direction, and m is an integer.
Claim 3
Dependent Claim
33 words
A method according to claim 1, wherein the number of scanning lines is selected so as to pass through areas of the dots where the halftone screen signals are of a maximum level.
Claim 4
Independent Claim
161 words
A method for forming a halftone screen in producing a halftone dot images by superposing image information produced by scanning an original on the halftone screen composed of a plurality of scanning lines constituted by electrically generated halftone screen signals and arranged side by side in a direction normal to a scanning direction in which the scanning lines extend, said method comprising the steps of: forming each dot of said halftone screen with an integral number of scanning lines commensurate with a screen angle of the halftone screen; and equalizing the halftone screen signals in level at mutually corresponding areas in the respective dots; wherein the halftone screen is composed of a repeated pattern of minimum basic periodic portions, the number α of scanning lines which constitute each of said basic periodic portions being selected on the following equation: ##EQU7## where θ is the screen angle, β is the number of scanning lines constituting a dot, and m is an integer.
Claim 5
Independent Claim
161 words
A method for forming a halftone screen in producing a halftone dot images by superposing image information produced by scanning an original on the halftone screen composed of a plurality of scanning lines constituted by electrically generated halftone screen signals and arranged side by side in a direction normal to a scanning direction in which the scanning lines extend, said method comprising the steps of: forming each dot of said halftone screen with an integral number of scanning lines commensurate with a screen angle of the halftone screen; and equalizing the halftone screen signals in level at mutually corresponding areas in the respective dots; wherein the halftone screen is composed of a repeated pattern of minimum basic periodic portions, the number α of scanning lines which constitute each of said basic periodic portions being selected on the following equation: ##EQU7## where θ is the screen angle, β is the number of scanning lines constituting a dot, and m is an integer.
Claim 6
Dependent Claim
33 words
A method according to claim 3, wherein the number of scanning lines is selected so as to pass through areas of the dots where the halftone screen signals are of a maximum level.
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) | 1991-09-27 | 1992-03-28 | 1992-09-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-09-27 | 1996-03-28 | 1996-09-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-09-27 | 2000-03-28 | 2000-09-27 | $7700.00 | Window Closed / Lapsed |