US3601018A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method and apparatus for exposing curved substrates
Assignee: Zenith Electronics LLC
•
Filing: 1968-08-26
•
Granted: 1971-08-24
•
Expires: 1988-08-26
Abstract
Abstract The internal surface of the curved faceplate of a color picture tube is coated with a photosensitive material to be selectively exposed through an aperture mask which has the same general configuration as the coated surface and is positioned in approximately spaced parallel relation thereto. The exposing light source is comprised of a planar source of diffused light disposed across a simulated color axis of the color picture tube, a spherical light stop concentric with that axis and defining the internal diameter of an annulus of light, and a planar light stop having a central aperture concentric with the spherical light stop and defining the external diameter of the annulus of light. The planar light stop is movable between a first position in which one half of the annulus of light is imaged on the peripheral portions of the substrate through the aperture mask and a second position in which the remaining light source is imaged on the same portions of the faceplate. The entire annulus of light is imaged on the central portion of the faceplate in each exposure step. The dimensions and shape imposed on the annulus of light by the dimensioning and configuration of the two light stops compensates the tendency to elliptical distortion introduced to the exposure light projected onto the substrate where that distortion is attributable to the curvature of the substrate and to the fact that the light source is displaced from the center of curvature of the faceplate.
Inventors
- 👤 Howard G Lange
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 06:29
CPC Classifications
H; H01; H01J; H01J9/00; H01J9/20; H01J9/22; H01J9/227; H01J9/2271; H01J9/2272
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
112 words
The method of exposing selected portions of the internal surface of a curved substrate which comprises: positioning in approximately spaced parallel relation to said substrate a mask having transparent and opaque portions collectively defining the exposure pattern desired for said substrate; and exposing said substrate through said mask, from an annular light source having dimensions large compared with the dimensions of said transparent portions of said mask, and in a series of N exposure steps in each of which a fractional portion of said light source is imaged on the edge portions of said substrate, where N is an integer At least equal to 2 and where said fractional portions are complementary.
Claim 2
Independent Claim
112 words
The method of exposing selected portions of the internal surface of a curved substrate which comprises: positioning in approximately spaced parallel relation to said substrate a mask having transparent and opaque portions collectively defining the exposure pattern desired for said substrate; and exposing said substrate through said mask, from an annular light source having dimensions large compared with the dimensions of said transparent portions of said mask, and in a series of N exposure steps in each of which a fractional portion of said light source is imaged on the edge portions of said substrate, where N is an integer At least equal to 2 and where said fractional portions are complementary.
Claim 3
Dependent Claim
33 words
The method as defined in claim 1 in which said light source is imaged on said substrate in two sequential steps in each of which at least half said light source is imaged.
Claim 4
Dependent Claim
79 words
The method as defined in claim 2 in which one half of said light source is imaged on the peripheral portions of said substrate in the first exposure step, in which the other half of said light source is imaged on the same peripheral portions of said substrate in the second exposure step, and in which the entirety of said light source is imaged on the central portion of said substrate in at least one of said exposure steps.
Claim 5
Dependent Claim
44 words
The method as defined in claim 2 in which said substrate has a predetermined radius of curvature and in which said light source is positioned concentrically of a reference axis at a distance from said substrate that is less than said radius of curvature.
Claim 6
Dependent Claim
88 words
The method as defined in claim 4 in which said light source is dimensioned in relation to the radius of curvature of said substrate and the angle between said reference axis and the edge of said substrate to project on the edge of said substrate in the first exposure step an arcuate pattern of light and to project thereon in the second exposure step a complementary arcuate pattern of light which, in conjunction with said first pattern, defines a ring pattern of light of a desired predetermined diameter.
Claim 7
Dependent Claim
132 words
The method as defined in claim 5 for exposing the internal surface of the curved substrate from an annular light source comprising a first spherically-shaped light stop determining the internal diameter of said source, a second light stop having circular aperture concentric with said first stop and determining the external diameter of source and a secondary diffused light source projecting light though the annulus defined by said light stops, which method comprises: positioning said second light stop at a first position on said reference axis to image approximately one half of said light source on said substrate in the first exposure step; and positioning said second light stop at a second position on said reference axis to image the reminder of said light source on said substrate in the second exposure step.
Claim 8
Dependent Claim
60 words
The method as defined in claim 6 in which said first position of said second light stop exposes certain portions of said substrate to one-half of the annulus of light projected from said source; and in which said second position of said second light stop exposes said portions of said substrate to the remaining half of the annulus of light.
Claim 9
Dependent Claim
45 words
The method as defined in claim 7 in which said first position of said second light stop exposes said portions of said substrate on one side of said reference axis to the half of the annulus of light on the opposite side of said axis.
Claim 10
Dependent Claim
142 words
Apparatus for exposing selected portions of the internal surface of a curved substrate which comprises: A mask in approximately spaced parallel relation to said substrate having transparent and opaque portions collectively defining the exposure pattern desired for said substrate; second light circular and an annular light source disposed substantially normal to a reference axis of said substrate, said light source comprising a first spherically shaped light stop positioned concentrically with said axis and determining the internal diameter of an annulus of light, a second light stop having a circular aperture concentric with said first stop and defining the external diameter of said annulus of light and movable between first and second positions spaced along said reference axis, and a source of diffused light transverse to said reference axis and projecting light through the annulus defined by said first and second light stops.
Claim 11
Dependent Claim
142 words
Apparatus for exposing selected portions of the internal surface of a curved substrate which comprises: A mask in approximately spaced parallel relation to said substrate having transparent and opaque portions collectively defining the exposure pattern desired for said substrate; second light circular and an annular light source disposed substantially normal to a reference axis of said substrate, said light source comprising a first spherically shaped light stop positioned concentrically with said axis and determining the internal diameter of an annulus of light, a second light stop having a circular aperture concentric with said first stop and defining the external diameter of said annulus of light and movable between first and second positions spaced along said reference axis, and a source of diffused light transverse to said reference axis and projecting light through the annulus defined by said first and second light stops.
Claim 12
Dependent Claim
56 words
Apparatus in accordance with claim 9 in which said first position of said second stop exposes certain portions of said substrate to approximately one half of said annular light source and in wHich said second position of said second light stop exposes said portions of said substrate to the remaining half of said annular light source.
Claim 13
Dependent Claim
58 words
Apparatus in accordance with claim 10 in which said second light stop is a planar opaque disc having a centrally located aperture, having a dimension in the direction of said axis that is small compared with the diameter of said spherically shaped first stop and disposed normal to said axis for displacement between said first and second positions.
Claim 14
Dependent Claim
55 words
Apparatus in accordance with claim 11 in which the diameter of said spherically shaped first stop is nonuniform to compensate the tendency of the curvature of said substrate to introduce elliptical distortion to the pattern of light projected from said annular light source onto portions of said substrate that are displaced from said reference axis.
Claim 15
Dependent Claim
40 words
Apparatus in accordance with claim 12 in which said spherically shaped first stop has a maximum diameter in a plane normal to said reference axis and a diameter which decreases with angular displacement in either direction from said normal plane.
References Cited (Backward Citations)
US3452655A
Cited
US3509802A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-08-23 | 1975-02-22 | 1975-08-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-08-23 | 1979-02-22 | 1979-08-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-08-23 | 1983-02-22 | 1983-08-24 | $7700.00 | Window Closed / Lapsed |