Patent US1961481A successfully refreshed from Google Patents.
Patent US3850628A successfully refreshed from Google Patents.
US3850628A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electrostatic modulator for controlling flow of charged particles
Assignee: Markem Imaje Corp
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Filing: 1972-09-22
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Granted: 1974-11-26
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Expires: 1992-09-22
Abstract
Abstract A system for controlling the flow of charged particles and for modulated aperture electrostatic printing. An apertured screen having substantially the entire surfaces formed of a dielectric material is charged with like charges over substantially all its surfaces to develop fringing fields in the apertures. The charge distributed across one side of the screen is selectively dissipated in accordance with a pattern to be reproduced thereby establishing a bipolar electrostatic latent image as a modification of the fringing fields for density control of a flow of charged particles directed through the screen. The screen may be formed with dielectric thicker on one face than the others to initially carry a higher potential and provide a uniform charge inequality or potential difference through the screen aperatures, oriented to enhance the flow of charged particles through the screen. Full modulation control of particle flow is therefore possible with a single selective charge dissipation. For electrostatic reproduction a print-receiving medium is interposed in the modulated particle flow passing through the screen.
Inventors
- 👤 Gerald L Pressman
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 04:56
CPC Classifications
G; G03; G03G; G03G15/00; G03G15/22; G03G15/34; G03G15/344; G03G15/346
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
158 words
A METHOD FOR MODULATING A FLOW OF IONS USING AN APERTURED SCREEN HAVING ALL ITS SURFACES FORMED OF AN INSULATIVE MATERIAL FORMED TO A PREDETERMINED THICKNESS ON THE FIRST FACE OF THE SCREEN GREATER THAN ON THE SECOND FACE COMPRISING: ESTABLISHING LIKE CHARGES OVER THE ENTIRE SURFACE OF SAID SCREEN AND DISTRIBUTING SAID CHARGES TO PROVIDE A GREATER SURFACE POTENTIAL ON THE FIRST FACE THAN ON THE SECOND THEREBY PROVIDING A UNIFORM CHARGE INEQUALITY BETWEEN THE FACES OF THE SCREEN WITH THE ELECTRIC FIELDS OF SUBSTANTIALLY UNIFORM MAGNITUDE AND ORIENTATION EXTENDING WITHIN THE SCREEN APERTURES BETWEEN THE FIRST AND SECOND FACES; SELECTIVELY DISSIPATING THE DISTRIBUTED CHARGES OVER THE FIRST FACE OF THE SCREEN IN ACCORDANCE WITH A PATTERN TO BE REPRODUCED THEREBY SELECTIVELY REDUCING, CANCELLING AND REVERSING ELECTRIC FIELDS EXTENDING WITHIN THE APERTURES; AND DIRECTING THE FLOW OF IONS THROUGH THE SCREEN APERTURES FOR SELECTIVELY ENHANCING, PASSING AND BLOCKING THE FLOW OF PARTICLES IN ACCORDANCE WITH THE PATTERN.
Claim 2
Independent Claim
158 words
A METHOD FOR MODULATING A FLOW OF IONS USING AN APERTURED SCREEN HAVING ALL ITS SURFACES FORMED OF AN INSULATIVE MATERIAL FORMED TO A PREDETERMINED THICKNESS ON THE FIRST FACE OF THE SCREEN GREATER THAN ON THE SECOND FACE COMPRISING: ESTABLISHING LIKE CHARGES OVER THE ENTIRE SURFACE OF SAID SCREEN AND DISTRIBUTING SAID CHARGES TO PROVIDE A GREATER SURFACE POTENTIAL ON THE FIRST FACE THAN ON THE SECOND THEREBY PROVIDING A UNIFORM CHARGE INEQUALITY BETWEEN THE FACES OF THE SCREEN WITH THE ELECTRIC FIELDS OF SUBSTANTIALLY UNIFORM MAGNITUDE AND ORIENTATION EXTENDING WITHIN THE SCREEN APERTURES BETWEEN THE FIRST AND SECOND FACES; SELECTIVELY DISSIPATING THE DISTRIBUTED CHARGES OVER THE FIRST FACE OF THE SCREEN IN ACCORDANCE WITH A PATTERN TO BE REPRODUCED THEREBY SELECTIVELY REDUCING, CANCELLING AND REVERSING ELECTRIC FIELDS EXTENDING WITHIN THE APERTURES; AND DIRECTING THE FLOW OF IONS THROUGH THE SCREEN APERTURES FOR SELECTIVELY ENHANCING, PASSING AND BLOCKING THE FLOW OF PARTICLES IN ACCORDANCE WITH THE PATTERN.
Claim 3
Dependent Claim
18 words
The method of claim 1 wherein the like charges are distributed heavier on one side of the screen.
Claim 4
Dependent Claim
29 words
The method of claim 2 wherein the selective dissipating is caused by a pattern of light and the insulative material on the first face comprises a photoconductive insulating material.
Claim 5
Dependent Claim
35 words
The method of claim 3 wherein the quantity of light in said pattern is sufficient to reduce the heavier charges on the one side to lesser charges than on the other side at selected locations.
Claim 6
Independent Claim
177 words
A method for modulating a flow of ions using an apertured screen having all its surfaces formed of an insulative material formed to a predetermined thickness on the first face of the screen greater than on the second face comprising: establishing and distributing like charges over the entire surfaces of the screen, and concentrating the charges to a greater potential on the first face of the screen than the other thereby creating a uniform charge inequality across the screen with electric fields of uniform magnitude and orientation extending through the apertures between the faces of the screen; orienting said screen and electric fields to enhance a flow of charged particles of predetermined charge directed through the screen apertures; selectively dissipating the distributed charges over the face of the screen having the greater potential in accordance with a pattern to be reproduced for selectively reducing, neutralizing and reversing the electric fields within the apertures; and directing the flow of ions through the screen thereby selectively enhancing, passing and blocking the flow of ions in accordance with the pattern.
Claim 7
Independent Claim
177 words
A method for modulating a flow of ions using an apertured screen having all its surfaces formed of an insulative material formed to a predetermined thickness on the first face of the screen greater than on the second face comprising: establishing and distributing like charges over the entire surfaces of the screen, and concentrating the charges to a greater potential on the first face of the screen than the other thereby creating a uniform charge inequality across the screen with electric fields of uniform magnitude and orientation extending through the apertures between the faces of the screen; orienting said screen and electric fields to enhance a flow of charged particles of predetermined charge directed through the screen apertures; selectively dissipating the distributed charges over the face of the screen having the greater potential in accordance with a pattern to be reproduced for selectively reducing, neutralizing and reversing the electric fields within the apertures; and directing the flow of ions through the screen thereby selectively enhancing, passing and blocking the flow of ions in accordance with the pattern.
Claim 8
Independent Claim
153 words
A method for controlling the cross-sectional deNsity of a stream of ions accelerated between a pair of electrodes through an apertured screen comprising: establishing charged layers of different potential on the opposite faces of said screen thereby providing a coplanar array of a plurality of electrostatic fields within the screen apertures between the faces of the screen, positioning the screen intermediate the accelerating electrode with lines of force generally parallel to the stream flow and orienting said electrostatic fields to enhance the stream flow; and selectively modifying the charge layers for selectively reducing, neutralizing and reversing said electrostatic fields extending within the screen apertures between the faces of the screen according to a pattern to be reproduced thereby establishing a bipolar electrostatic latent image of a coplanar array of generally parallel fields of selected magnitude and direction within the apertures for selectively enhancing, passing, blocking and thereby modulating the ion stream flow density.
Claim 9
Independent Claim
153 words
A method for controlling the cross-sectional deNsity of a stream of ions accelerated between a pair of electrodes through an apertured screen comprising: establishing charged layers of different potential on the opposite faces of said screen thereby providing a coplanar array of a plurality of electrostatic fields within the screen apertures between the faces of the screen, positioning the screen intermediate the accelerating electrode with lines of force generally parallel to the stream flow and orienting said electrostatic fields to enhance the stream flow; and selectively modifying the charge layers for selectively reducing, neutralizing and reversing said electrostatic fields extending within the screen apertures between the faces of the screen according to a pattern to be reproduced thereby establishing a bipolar electrostatic latent image of a coplanar array of generally parallel fields of selected magnitude and direction within the apertures for selectively enhancing, passing, blocking and thereby modulating the ion stream flow density.
Claim 10
Dependent Claim
65 words
A method for controlling a stream of ions as set forth in claim 6 wherein the steps of selectively modifying the charge layers for selectively reducing, neutralizing and reversing include the steps of illuminating the apertured screen with an image to be reproduced and selectively reducing, neutralizing and reversing said bipolar electrostatic fields according to the light intensity on different portions of the apertured screen.
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) | 1977-11-25 | 1978-05-27 | 1978-11-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-11-25 | 1982-05-27 | 1982-11-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-11-25 | 1986-05-27 | 1986-11-26 | $7700.00 | Window Closed / Lapsed |