US4251625A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of producing a halftone picture by vibrating light source
Assignee: Dainippon Screen Manufacturing Co Ltd
•
Filing: 1978-10-26
•
Granted: 1981-02-17
•
Expires: 1998-10-26
Abstract
Abstract A spot of light is formed upon a photosensitive material which is moved in a scanning direction, and the spot is vibrated to and fro along a vibration direction at a considerable angle to the scanning direction, and the amplitude of vibration, and the center of the vibration path, are controlled so that the spot exposes areas on the photosensitive material which form half-tone dots.
Inventors
- 👤 Seiya Sakamoto
- 👤 Tetsuo Hohki
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 16:12
CPC Classifications
H; H04; H04N; H04N1/00; H04N1/40; H04N1/405; H04N1/4055; H04N1/4058
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
155 words
A method for producing a half-tone picture on a photosensitive material, wherein the halftone dots are produced along a line of an arbitrary screen angle with respect to a scanning direction, comprising the steps of: forming a spot of light on the surface of the material; causing a motion of the material relative to the spot in a scanning direction; vibrating the spot to and fro along a vibration direction which is at a substantial angle to the scanning direction through a certain vibration width about a central point, the vibration center; and controlling the amplitude of the vibration width and the position of the vibration center by guiding the center of the vibration along a line substantially equal to the screen angle with respect to the scanning direction so that the spot exposes areas on the photosensitive material which form half-tone dots, as the material moves relative to the spot in the scanning direction.
Claim 2
Independent Claim
155 words
A method for producing a half-tone picture on a photosensitive material, wherein the halftone dots are produced along a line of an arbitrary screen angle with respect to a scanning direction, comprising the steps of: forming a spot of light on the surface of the material; causing a motion of the material relative to the spot in a scanning direction; vibrating the spot to and fro along a vibration direction which is at a substantial angle to the scanning direction through a certain vibration width about a central point, the vibration center; and controlling the amplitude of the vibration width and the position of the vibration center by guiding the center of the vibration along a line substantially equal to the screen angle with respect to the scanning direction so that the spot exposes areas on the photosensitive material which form half-tone dots, as the material moves relative to the spot in the scanning direction.
Claim 3
Dependent Claim
23 words
A method as in claim 1, wherein the screen angle of the half-tone dots produced with respect to the scanning direction is non-zero.
Claim 4
Dependent Claim
19 words
A method as in claim 1, wherein the angle between the scanning direction and the vibration direction is 90°.
Claim 5
Dependent Claim
19 words
A method as in claim 2, wherein the angle between the scanning direction and the vibration direction is 90°.
Claim 6
Dependent Claim
37 words
A method as in claim 2, wherein the angle between the scanning direction and the vibration direction, added to the screen angle with respect to the scanning direction of the half-tone dots which are produced, is 90°.
Claim 7
Independent Claim
25 words
A method as in any of claims 1-5, wherein the spot is vibrated by an optical inclinator element which is controlled by a frequency-modulated signal.
Claim 8
Independent Claim
36 words
A method as in any of claims 1-5, wherein the brightness of the spot is controlled to be according to the vibration width by an optical modulator element which is controlled by an amplitude modulated signal.
Claim 9
Dependent Claim
34 words
A method as in claim 6, wherein the brightness of the spot is controlled to be according to the vibration width by an optical modulator element which is controlled by an amplitude modulated signal.
Claim 10
Independent Claim
61 words
A method as in any of claims 1-5, wherein the spot is controlled by an optical inclinator/modulator element which is controlled by a signal, the frequency of the signal controlling the optical inclinator/modulator element to vibrate the spot, and the amplitude of the signal controlling the optical inclinator/modulator element to control the brightness of the spot according to the vibration width.
Claim 11
Independent Claim
39 words
The method as in any of claims 1-5, wherein the material also moves, in a direction perpendicular to the scanning direction, relative to the spot, at a speed which is low relative to the motion along the scanning direction.
References Cited (Backward Citations)
US3075042A
Cited
US3461229A
Cited
US3667947A
Cited
US3668311A
Cited
US3737225A
Cited
US3888673A
Cited
US3867150A
Cited
US3985439A
Cited
US4004079A
Cited
US4053906A
Cited
US4149194A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1984-02-17 | 1984-08-18 | 1985-02-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-02-17 | 1988-08-18 | 1989-02-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-02-17 | 1992-08-18 | 1993-02-17 | $7700.00 | Window Closed / Lapsed |