US4164059A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of manufacturing a color display tube and color display tube manufactured by said method
Assignee: US Philips Corp
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Filing: 1978-04-19
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Granted: 1979-08-14
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Expires: 1998-04-19
Abstract
Abstract A focusing shadow mask incorporating an electrostatic lens at each mask aperture is produced by creating an electrode comprising a set of parallel conductors on one surface of an insulator sheet and a second electrode on the other surface. The second electrode has apertures defined either by a second set of parallel conductors that are perpendicular to the first set or by a conductive grid that includes conductors parallel to the first set and other conductors perpendicular to the first set. Additional metal can be built up on either electrode to strengthen the combined structure. After formation of both electrodes, the areas of the insulating material are selectively etched away to form apertures for beams to pass through.
Inventors
- 👤 Johannes van Esdonk
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 14:35
CPC Classifications
H; H01; H01J; H01J9/00; H01J9/02; H01J9/14; H01J9/142; H01J29/00; H01J29/46; H01J29/80; H01J29/81
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
179 words
In the manufacture of a colour cathode ray tube having a focusing shadow mask, the method comprising the steps of: forming on one surface of an electrically insulating sheet a first electrode affixed to said sheet and having a plurality of elongated metallic conductors spaced from each other to define a first plurality of openings therebetween; forming on the opposite surface of said sheet a second electrode affixed to said sheet and having a plurality of elongated metallic conductors spaced from each other to define a second plurality of openings therebetween such that a portion of each opening of said second plurality is aligned with a portion of one of said openings of said first plurality; etching through said sheet at regions thereof aligned with said aligned portions of said openings to form apertures for passing electrons therethrough, said conductors of said first and second electrodes defining an electron lens for producing electron focusing fields in said apertures and with said sheet forming said shadow mask; and mounting said shadow mask in an envelope of the cathode ray tube.
Claim 2
Dependent Claim
179 words
In the manufacture of a colour cathode ray tube having a focusing shadow mask, the method comprising the steps of: forming on one surface of an electrically insulating sheet a first electrode affixed to said sheet and having a plurality of elongated metallic conductors spaced from each other to define a first plurality of openings therebetween; forming on the opposite surface of said sheet a second electrode affixed to said sheet and having a plurality of elongated metallic conductors spaced from each other to define a second plurality of openings therebetween such that a portion of each opening of said second plurality is aligned with a portion of one of said openings of said first plurality; etching through said sheet at regions thereof aligned with said aligned portions of said openings to form apertures for passing electrons therethrough, said conductors of said first and second electrodes defining an electron lens for producing electron focusing fields in said apertures and with said sheet forming said shadow mask; and mounting said shadow mask in an envelope of the cathode ray tube.
Claim 3
Dependent Claim
52 words
The method according to claim 1, wherein said etching step includes etching away substantially all portions of said sheet not in contact with said conductors of said first and second electrodes so that the rigidity of the resultant shadow mask is determined mainly by said conductors of said first and second electrodes.
Claim 4
Dependent Claim
106 words
The method according to claim 1 wherein the step of forming said first electrode includes the step of etching away portions of a metal layer on said one surface of said sheet to form a first set of parallel metal strips defining said conductors of said first electrode and the step of forming said second electrode includes the step of etching away portions of a second metal layer on said opposite surface of said sheet to form a second set of parallel metal strips extending transversely of said strips of said first set, said strips of said second set defining said conductors of said second electrode.
Claim 5
Dependent Claim
43 words
The method according to claim 3 wherein said step of etching through said sheet includes underetching said sheet underlying said strips of one of said sets so that the remaining portions of said sheet are narrower than said strips of said one set.
Claim 6
Dependent Claim
33 words
The method according to claim 4 wherein the step of etching through said sheet includes etching away all portions of said sheet not sandwiched between said strips of said first and second sets.
Claim 7
Dependent Claim
128 words
The method according to claim 1 wherein said step of forming said first electrode includes etching away a plurality of substantially rectangular portions of a metal layer on said one surface of said sheet to leave two sets of parallel metal strips defining said elongated conductors of said first electrode, the strips of one of said sets extending perpendicularly to the strips of the other set; and the step of forming said second electrode includes the step of etching away portions of a second metal layer on said opposite surface of said sheet to leave a third set of parallel metal strips aligned with and parallel to the strips of one of said two sets, said strips of said third set defining said conductors of said second electrode.
Claim 8
Dependent Claim
104 words
The method according to claim 1 wherein said insulating sheet is made of synthetic material and said step of forming said first electrode includes the steps of adhereing a metal sheet to said one surface of said insulating sheet, said step of adhereing including applying to said metal sheet an adhesive of synthetic material convertible to said first-named synthetic material, pressing said metal sheet against said one surface and converting said adhesive to said first-named material; and removing selected areas of said metal sheet to form said first plurality of openings therein, said metal sheet with said openings formed therein defining said first electrode.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1982-08-13 | 1983-02-12 | 1983-08-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1986-08-13 | 1987-02-12 | 1987-08-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1990-08-13 | 1991-02-12 | 1991-08-14 | $7700.00 | Window Closed / Lapsed |