US4604654A
Expired / Lapsed
US
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Image forming method and apparatus
Assignee: Canon Inc
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Filing: 1985-07-26
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Granted: 1986-08-05
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Expires: 2005-07-26
Abstract
Abstract An image forming method comprises the steps of providing pattern elementary marks which provide an image pattern, controlling the size of the pattern elementary marks, and forming the pattern elementary marks substantially at equal intervals. The controlling step is such that use is made preferentially of the pattern elementary marks in an area wherein the variation in density gradient level relative to the variation in size of the pattern elementary marks is great. An apparatus for carrying out such method is provided.
Inventors
- 👤 Nobuaki Sakurada
- 👤 Yoshitaka Watanabe
- 👤 Hideaki Kawamura
- 👤 Yuichi Sato
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 18:02
CPC Classifications
H; H04; H04N; H04N1/00; H04N1/024; H04N1/032; H04N1/034; B; B41; B41J; B41J2/00; B41J2/005; B41J2/01; B41J2/21; B41J2/2121; B41J2/2125; H04N1/40; H04N1/40025; H04N1/40031; H04N1/40087; B41J2202/00; B41J2202/01; B41J2202/11
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
259 words
An image forming method for forming on a medium an image pattern comprising a plurality of picture elements with different light-reflecting properties providing different optical reflection densities by using pattern elementary marks on the medium at a substantially constant pitch to form the picture elements, the method comprising the steps of: determining within which of a first optical reflection density range and a second optical reflection density range the optical reflection density of an area of the image pattern falls, the first range having an upper limit higher than the lower limit of the second range; providing a pattern elementary mark with a first density when the optical reflection density of an area of the image pattern to be depicted thereby is in the first optical reflection density range, the pattern elementary mark having a size that provides the image area depicted thereby an optical reflection density substantially the same as the determined optical reflection density; providing a pattern elementary mark with a second density higher than the first density when the optical reflection density of an area of the image pattern to be depicted thereby is in the second optical reflection density range, the pattern elementary mark having a size that provides the image area depicted thereby with an optical reflection density substantially the same as the determined optical reflection density; and setting the optical reflection density ranges so that efficient representation of the optical reflection densitites of the image pattern throughout the image can be performed by the pattern elementary marks having the first and second densities.
Claim 2
Dependent Claim
259 words
An image forming method for forming on a medium an image pattern comprising a plurality of picture elements with different light-reflecting properties providing different optical reflection densities by using pattern elementary marks on the medium at a substantially constant pitch to form the picture elements, the method comprising the steps of: determining within which of a first optical reflection density range and a second optical reflection density range the optical reflection density of an area of the image pattern falls, the first range having an upper limit higher than the lower limit of the second range; providing a pattern elementary mark with a first density when the optical reflection density of an area of the image pattern to be depicted thereby is in the first optical reflection density range, the pattern elementary mark having a size that provides the image area depicted thereby an optical reflection density substantially the same as the determined optical reflection density; providing a pattern elementary mark with a second density higher than the first density when the optical reflection density of an area of the image pattern to be depicted thereby is in the second optical reflection density range, the pattern elementary mark having a size that provides the image area depicted thereby with an optical reflection density substantially the same as the determined optical reflection density; and setting the optical reflection density ranges so that efficient representation of the optical reflection densitites of the image pattern throughout the image can be performed by the pattern elementary marks having the first and second densities.
Claim 3
Dependent Claim
44 words
An image forming apparatus for performing the method according to claim 1, comprising: a first ink jet head for providing the pattern elementary mark with the first density; and a second ink jet head for providing the pattern elementary mark with the second density.
Claim 4
Dependent Claim
37 words
An image forming apparatus according to claim 2, wherein each said ink jet head includes a piezo element, and the size of said pattern elementary marks is determined by the a voltage applied to said piezo element.
Claim 5
Dependent Claim
248 words
An image forming method for forming on a medium an image pattern comprising a plurality of picture elements with different light-reflecting properties providing different optical reflection densities by using pattern elementary marks on the medium at a substantially constant pitch to form the picture elemtns, the mehtod comprising the steps of: determining within which of a first optical reflection density range and a second optical reflection density range the optical reflection density of an area of the image pattern falls, the first range having an upper limit higher than the lower limit of the second range; providing a pattern elementary mark with a first density when the optical reflection density of an area of the image pattern to be depicted thereby is in the first optical reflection density range, the pattern elementary mark having a size that provides the image area depicted thereby with an optical reflection density substantially the same as the determined optical reflection density; providing a pattern elementary mark with a second density higher than the first density when the optical reflection density of an area of the image pattern to be depicted thereby is in the second optical reflection density range, the pattern elementary mark having a size that provides the image area depicted thereby with an optical reflection density substantially the same as the determined optical reflection density; and setting the ratio of the maximum size of the pattern elementary mark with the first density to the pitch thereof to less than 1.4.
Claim 6
Dependent Claim
248 words
An image forming method for forming on a medium an image pattern comprising a plurality of picture elements with different light-reflecting properties providing different optical reflection densities by using pattern elementary marks on the medium at a substantially constant pitch to form the picture elemtns, the mehtod comprising the steps of: determining within which of a first optical reflection density range and a second optical reflection density range the optical reflection density of an area of the image pattern falls, the first range having an upper limit higher than the lower limit of the second range; providing a pattern elementary mark with a first density when the optical reflection density of an area of the image pattern to be depicted thereby is in the first optical reflection density range, the pattern elementary mark having a size that provides the image area depicted thereby with an optical reflection density substantially the same as the determined optical reflection density; providing a pattern elementary mark with a second density higher than the first density when the optical reflection density of an area of the image pattern to be depicted thereby is in the second optical reflection density range, the pattern elementary mark having a size that provides the image area depicted thereby with an optical reflection density substantially the same as the determined optical reflection density; and setting the ratio of the maximum size of the pattern elementary mark with the first density to the pitch thereof to less than 1.4.
Claim 7
Dependent Claim
42 words
An image forming method accordind to claim 4, wherein in the first optical reflection density range a plot of the sizes of pattern elementary marks having the first density, versus the optical reflection densities provided thereby, results in a substantially linear curve.
Claim 8
Dependent Claim
15 words
An image forming method according to claim 4, wherein said ratio is 1.25 or less.
Claim 9
Dependent Claim
15 words
An image forming method according to claim 4, wherein said pattern elementary marks are circular.
References Cited (Backward Citations)
US1790723A
Cited
US1656338A
Cited
US1817098A
Cited
US3197558A
Cited
US3681650A
Cited
US3739084A
Cited
US3683212A
Cited
US3747120A
Cited
US3864696A
Cited
US4050077A
Cited
US3977007A
Cited
US4389712A
Cited
US4468706A
Cited
US4394693A
Cited
US4353079A
Cited
US4342051A
Cited
US4339774A
Cited
US4368491A
Cited
US4403874A
Cited
US4547812A
Cited
US4413275A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1989-08-04 | 1990-02-03 | 1990-08-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-08-04 | 1994-02-03 | 1994-08-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-08-04 | 1998-02-03 | 1998-08-05 | $7700.00 | Window Closed / Lapsed |