US4257072A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method and apparatus using multiple deflections for reproducing a halftone image by scanning
Assignee: Dainippon Screen Manufacturing Co Ltd
•
Filing: 1977-10-17
•
Granted: 1981-03-17
•
Expires: 1997-10-17
Abstract
Abstract A method and an apparatus for reproducing a halftone image by scanning without any use of a contact screen, wherein a recording light beam of horizontally flat shape scans the surface of an aperture plate and is suitably deflected in both vertical and horizontal directions by image signals obtained from a memory according to the scanning of an original picture. The vertical deflection of the beam makes it possible for the beam width to change or the width of an intercepted portion of the beam to change, and the horizontal deflection of the beam makes it possible for the center of the beam to shift sideways in proportion to the tone density in the original as well as a required screen angle. The reproduced halftone image may have any of a range of screen angles. Further, the resolving power is greatly increased; in other words, continuous tone in the original may be more accurately reproduced since it is possible to set a width of scanning line which is narrower than the halftone dot interval.
Inventors
- 👤 Takashi Sakamoto
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 04:30
CPC Classifications
H; H04; H04N; H04N1/00; H04N1/024; H04N1/032; H04N1/036; H04N1/40; H04N1/405; H04N1/4055; H04N1/4058
Claims Analysis
Total Claims: 29
Claim 1
Independent Claim
195 words
Apparatus for reproducing a halftone image by scanning, wherein a scanning beam to be projected upon a photosensitive material is suitably controlled by means of image signals obtained from the scanning of an original, said apparatus comprising: generating means means for generating image signals by scanning said original along a predetermined scanning direction, a light source for emitting a beam for exposure, first deflection means adapted for deflecting said beam in the scanning direction of the photosensitive material, second deflection means disposed downstream along the light beam of said first deflection means and adapted for deflecting the beam in a direction parallel to the scanning direction, an aperture plate disposed between said first and second deflection means and adapted for intercepting at least a portion of the width of the beam, third deflection means adapted for deflecting the beam which has passed through the second deflection means in a direction orthogonal to the scanning direction, an optical system for focusing the beam from said third deflection means onto the photosensitive material, and control means for controlling deflection angles at said first, second and third deflection means in response to the intensity of said image signals.
Claim 2
Dependent Claim
195 words
Apparatus for reproducing a halftone image by scanning, wherein a scanning beam to be projected upon a photosensitive material is suitably controlled by means of image signals obtained from the scanning of an original, said apparatus comprising: generating means means for generating image signals by scanning said original along a predetermined scanning direction, a light source for emitting a beam for exposure, first deflection means adapted for deflecting said beam in the scanning direction of the photosensitive material, second deflection means disposed downstream along the light beam of said first deflection means and adapted for deflecting the beam in a direction parallel to the scanning direction, an aperture plate disposed between said first and second deflection means and adapted for intercepting at least a portion of the width of the beam, third deflection means adapted for deflecting the beam which has passed through the second deflection means in a direction orthogonal to the scanning direction, an optical system for focusing the beam from said third deflection means onto the photosensitive material, and control means for controlling deflection angles at said first, second and third deflection means in response to the intensity of said image signals.
Claim 3
Dependent Claim
31 words
An apparatus according to claim 1, further including screening means having an aperture for limiting the width of said beam to be projected on the photosensitive material to a predetermined value.
Claim 4
Dependent Claim
18 words
An apparatus according to claim 1, wherein said aperture plate has a beam-admitting aperture and a beam-intercepting portion.
Claim 5
Dependent Claim
20 words
An apparatus according to claim 1, wherein said first, second and third deflection means are acoustic-optical deflectors utilizing ultrasonic oscillators.
Claim 6
Dependent Claim
31 words
An apparatus according to claim 1, wherein said aperture plate is adapted to separate the beam into separate spaced beam portions when recording a halftone image equal to at least 50%.
Claim 7
Dependent Claim
40 words
An apparatus according to claim 1, wherein said aperture plate has an aperture one part of which is triangle-shaped and is used to modify the beam when recording a halftone image of less than or equal to 50% dot area.
Claim 8
Dependent Claim
47 words
An apparatus according to claim 1, wherein said aperture plate has an aperture one part of which has an opague triangle shape protruding into it, said part being used to modify the beam when recording a halftone image of less than or equal to 50% dot area.
Claim 9
Dependent Claim
50 words
An apparatus according to claim 1, further including a further optical system for converging, in the direction parallel to the scanning direction, the beam deflected at the first deflection means onto said aperture plate and diffusing said beam to make it flat in the direction orthogonal to the scanning direction.
Claim 10
Dependent Claim
20 words
An apparatus according to claim 8, wherein said further optical system comprises a cylindrical plate and a one-way diffusion lens.
Claim 11
Independent Claim
160 words
A method for reproducing a halftone image corresponding to an original picture, comprising the steps of: (a) scanning the original picture and generating a picture signal which is a function of the tone and intensity thereof; (b) forming two halftone control signals on the basis of said picture signal; (c) producing a scanning light beam, which when focused is of very small height in comparison to its width; (d) varying the width of the scanning beam in accordance with one of said halftone control signals, and varying the position of its center, in the widthwise direction, in accordance with the other of said halftone control signals; and (e) scanning the scanning beam along a piece of photosensitive material in the direction orthogonal to the widthwise direction, said halftone control signals being functions of time and of said picture signal for the beam to expose a pattern on the photosensitive material which consists of halftone dots which represent the original picture.
Claim 12
Independent Claim
160 words
A method for reproducing a halftone image corresponding to an original picture, comprising the steps of: (a) scanning the original picture and generating a picture signal which is a function of the tone and intensity thereof; (b) forming two halftone control signals on the basis of said picture signal; (c) producing a scanning light beam, which when focused is of very small height in comparison to its width; (d) varying the width of the scanning beam in accordance with one of said halftone control signals, and varying the position of its center, in the widthwise direction, in accordance with the other of said halftone control signals; and (e) scanning the scanning beam along a piece of photosensitive material in the direction orthogonal to the widthwise direction, said halftone control signals being functions of time and of said picture signal for the beam to expose a pattern on the photosensitive material which consists of halftone dots which represent the original picture.
Claim 13
Dependent Claim
150 words
A method according to claim 10, wherein at a point of focusing of said beam there is placed in the path of the beam an aperture plate, and wherein in the path of the beam, both before and after the aperture plate, there are placed means for deflecting the beam in directions orthogonal to its widthwise direction, said one halftone control signal being fed to both of said deflecting means and controlling them so as to deflect the beam in opposite senses, so that the beam, after having passed both said deflecting means, is substantially undeflected in the direction orthogonal to its widthwise direction, and so that the beam, where it passes the aperture plate, is moved substantially in the direction orthogonal to its widthwise direction as a function of said one halftone control signal, said aperture plate intercepting a varying portion of said beam as it is thus moved.
Claim 14
Dependent Claim
130 words
A method according to claim 11, wherein said aperture plate has a first portion which is configured to allow only a section of the beam which is of a width which varies according to the lengthwise deflection of the beam to pass, and a second portion which is configured to intercept a portion of the beam which is of a width which varies according to the lengthwise deflection of the beam, allowing parts of the beam on both sides of said intercepted portion of the beam to pass, and wherein said first portion is used when recording halftone dots which have less than or equal to 50% dot area, and the second portion is used when recording halftone dots which have greater than or equal to 50% halftone dot area.
Claim 15
Dependent Claim
146 words
A method according to claim 10, wherein at a point of focusing of said beam, said step of varying said width comprises the step of deflecting the beam in directions orthogonal to its widthwise direction both before and after an aperture plate which is placed in the path of the beam, said orthogonal deflections being a function of said one halftone control signal which is used to deflect the beam in opposite senses on opposite sides of said aperture plate, so that the beam, after having been twice deflected, is substantially undeflected in the direction orthogonal to its widthwise direction. and so that the beam, where it passes the aperture plate, is moved substantially in the direction orthogonal to its widthwise direction as a function of said one halftone control signal, said aperture plate intercepting a varying portion of said beam as it is thus moved.
Claim 16
Dependent Claim
130 words
A method according to claim 13, wherein said aperture plate has a first portion which is configured to allow only a section of the beam which is of a width which varies according to the lengthwise deflection of the beam to pass, and a second portion which is configured to intercept a portion of the beam which is of a width which varies according to the lengthwise deflection of the beam, allowing parts of the beam on both sides of said intercepted portion of the beam to pass, and wherein said first portion is used when recording halftone dots which have less than or equal to 50% dot area, and the second portion is used when recording halftone dots which have greater than or equal to 50% halftone dot area.
Claim 17
Independent Claim
68 words
A method for reproducing a halftone image corresponding to an original picture, comprising the steps of: (a) scanning the original picture and generating a picture signal which is a function of the tone and intensity thereof; (b) forming two halftone control signals on the basis of said picture signal; (c) producing a scanning light beam, which when focused is of very small height in comparison to its width;
Claim 18
Independent Claim
68 words
A method for reproducing a halftone image corresponding to an original picture, comprising the steps of: (a) scanning the original picture and generating a picture signal which is a function of the tone and intensity thereof; (b) forming two halftone control signals on the basis of said picture signal; (c) producing a scanning light beam, which when focused is of very small height in comparison to its width;
Claim 19
Dependent Claim
99 words
(d) varying the width of an intercepted portion of the beam in accordance with one of said halftone control signals, and varying the position of the center of said intercepted portion, in the widthwise direction, in accordance with the other of said halftone control signals; and (e) scanning the scanning beam along a piece of photosensitive material in the direction orthogonal to the widthwise direction, said halftone control signals being functions of time and of said picture signal for the beam to expose a pattern on the photosensitive material which consists of halftone dots which represent the original picture.
Claim 20
Dependent Claim
99 words
(d) varying the width of an intercepted portion of the beam in accordance with one of said halftone control signals, and varying the position of the center of said intercepted portion, in the widthwise direction, in accordance with the other of said halftone control signals; and (e) scanning the scanning beam along a piece of photosensitive material in the direction orthogonal to the widthwise direction, said halftone control signals being functions of time and of said picture signal for the beam to expose a pattern on the photosensitive material which consists of halftone dots which represent the original picture.
Claim 21
Dependent Claim
150 words
A method according to claim 15, wherein at a point of focusing of said beam there is placed in the path of the beam an aperture plate, and wherein in the path of the beam, both before and after the aperture plate, there are placed means for deflecting the beam in directions orthogonal to its widthwise direction, said one halftone control signal being fed to both of said deflecting means and controlling them so as to deflect the beam in opposite senses, so that the beam, after having passed both said deflecting means, is substantially undeflected in the direction orthogonal to its widthwise direction, and so that the beam, where it passes the aperture plate, is moved substantially in the direction orthogonal to its widthwise direction as a function of said one halftone control signal, said aperture plate intercepting a varying portion of said beam as it is thus moved.
Claim 22
Dependent Claim
130 words
A method according to claim 16, wherein said aperture plate has a first portion which is configured to allow only a section of the beam which is of a width which varies according to the lengthwise deflection of the beam to pass, and a second portion which is configured to intercept a portion of the beam which is of a width which varies according to the lengthwise deflection of the beam, allowing parts of the beam on both sides of said intercepted portion of the beam to pass, and wherein said first portion is used when recording halftone dots which have less than or equal to 50% dot area, and the second portion is used when recording halftone dots which have greater than or equal to 50% halftone dot area.
Claim 23
Dependent Claim
146 words
A method according to claim 15, wherein at a point of focusing of said beam, said step of varying said width comprises the step of deflecting the beam in directions orthogonal to its widthwise direction both before and after an aperture plate which is placed in the path of the beam, said orthogonal deflections being a function of said one halftone control signal which is used to deflect the beam in opposite senses on opposite sides of said aperture plate, so that the beam, after having been twice deflected, is substantially undeflected in the direction orthogonal to its widthwise direction, and so that the beam, where it passes the aperture plate, is moved substantially in the direction orthogonal to its widthwise direction as a function of said one halftone control signal, said aperture plate intercepting a varying portion of said beam as it is thus moved.
Claim 24
Dependent Claim
130 words
A method according to claim 18, wherein said aperture plate has a first portion which is configured to allow only a section of the beam which is of a width which varies according to the lengthwise deflection of the beam to pass, and a second portion which is configured to intercept a portion of the beam which is of a width which varies according to the lengthwise deflection of the beam, allowing parts of the beam on both sides of said intercepted portion of the beam to pass, and wherein said first portion is used when recording halftone dots which have less than or equal to 50% dot area, and the second portion is used when recording halftone dots which have greater than or equal to 50% halftone dot area.
Claim 25
Independent Claim
284 words
A method for reproducing a halftone image corresponding to an original picture signal, comprising the steps of: (a) scanning the original picture along a predetermined lengthwise direction and generating a picture signal which is a function of the tone and the intensity thereof; (b) forming two halftone control signals on the basis of said picture signal; (c) producing a scanning light beam which when focused is of very small height in comparison to its width; (d) passing said beam through a first means for deflecting it in the lengthwise direction; (e) focusing said beam on an aperture plate; (f) passing said beam through a second means for deflecting it in the lengthwise direction; (g) passing said beam through a third means for deflecting it in the widthwise direction normal to the lengthwise direction; and (h) focusing said beam on a piece of photosensitive material which is moved in the lengthwise direction of the beam, said first and second deflecting means being fed with and controlled by one of said halftone control signals, and deflecting the beam in opposite senses, so that the beam, where it is focused on the photosensitive material, is not substantially deflected in the lengthwise direction, and so that, where the beam is focused on said aperture plate, it is deflected substantially in the lengthwise direction, said aperture plate intercepting a varying portion of said beam as it is thus deflected, said third deflecting means being fed with and controlled by the other of said halftone control signals, said halftone control signals being functions of time and said picture signal for the beam to expose a pattern on the photosensitive material which consists of halftone dots which represent the original picture.
Claim 26
Independent Claim
284 words
A method for reproducing a halftone image corresponding to an original picture signal, comprising the steps of: (a) scanning the original picture along a predetermined lengthwise direction and generating a picture signal which is a function of the tone and the intensity thereof; (b) forming two halftone control signals on the basis of said picture signal; (c) producing a scanning light beam which when focused is of very small height in comparison to its width; (d) passing said beam through a first means for deflecting it in the lengthwise direction; (e) focusing said beam on an aperture plate; (f) passing said beam through a second means for deflecting it in the lengthwise direction; (g) passing said beam through a third means for deflecting it in the widthwise direction normal to the lengthwise direction; and (h) focusing said beam on a piece of photosensitive material which is moved in the lengthwise direction of the beam, said first and second deflecting means being fed with and controlled by one of said halftone control signals, and deflecting the beam in opposite senses, so that the beam, where it is focused on the photosensitive material, is not substantially deflected in the lengthwise direction, and so that, where the beam is focused on said aperture plate, it is deflected substantially in the lengthwise direction, said aperture plate intercepting a varying portion of said beam as it is thus deflected, said third deflecting means being fed with and controlled by the other of said halftone control signals, said halftone control signals being functions of time and said picture signal for the beam to expose a pattern on the photosensitive material which consists of halftone dots which represent the original picture.
Claim 27
Dependent Claim
55 words
A method according to claim 20, further including the step of passing the beam past a screening plate, said step being performed prior to focusing of said beam on a piece of photosensitive material, said screening plate intercepting any portions of the beam which are more than a certain fixed distance from a central point.
Claim 28
Independent Claim
208 words
A method for reproducing a halftone image corresponding to an original picture, comprising the steps of: (a) scanning the original picture and generating a picture signal which is a function of the tone and intensity thereof; (b) forming two halftone control signals on the basis of said picture signal; (c) producing a scanning light beam, which when focused is of very small height in comparison to its width; (d) selectively transmitting a portion of said beam through a screening plate during formation of halftone dot areas below a predetermined value and intercepting a portion of said beam through said screening plate during formation of halftone dot areas above said predetermined value; (e) varying the width of the respective transmitted and intercepted beam portions in accordance with one of said halftone control signals, and varying the positions of their centers, in their widthwise directions, as a function of said other of said halftone control signals; and (f) scanning the scanning beam along a piece of photosensitive material in the direction orthogonal to the widthwise direction, said halftone control signals being functions of time and of said picture signal for the beam to expose a pattern on the photosensitive material which consists of halftone dots which represent the original picture.
Claim 29
Independent Claim
208 words
A method for reproducing a halftone image corresponding to an original picture, comprising the steps of: (a) scanning the original picture and generating a picture signal which is a function of the tone and intensity thereof; (b) forming two halftone control signals on the basis of said picture signal; (c) producing a scanning light beam, which when focused is of very small height in comparison to its width; (d) selectively transmitting a portion of said beam through a screening plate during formation of halftone dot areas below a predetermined value and intercepting a portion of said beam through said screening plate during formation of halftone dot areas above said predetermined value; (e) varying the width of the respective transmitted and intercepted beam portions in accordance with one of said halftone control signals, and varying the positions of their centers, in their widthwise directions, as a function of said other of said halftone control signals; and (f) scanning the scanning beam along a piece of photosensitive material in the direction orthogonal to the widthwise direction, said halftone control signals being functions of time and of said picture signal for the beam to expose a pattern on the photosensitive material which consists of halftone dots which represent the original picture.
References Cited (Backward Citations)
US2124030A
Cited
US2152348A
Cited
US2294643A
Cited
US2468049A
Cited
US2818465A
Cited
US3646262A
Cited
US3541253A
Cited
US3657472A
Cited
US3800303A
Cited
US3944323A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1984-03-16 | 1984-09-15 | 1985-03-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-03-16 | 1988-09-15 | 1989-03-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-03-16 | 1992-09-15 | 1993-03-17 | $7700.00 | Window Closed / Lapsed |