US3873877A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Mislanding corrector for color cathode ray tubes
Assignee: Sony Corp
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Filing: 1973-11-20
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Granted: 1975-03-25
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Expires: 1993-11-20
Abstract
Abstract A temperature-responsive magnetic device comprising a pair of permanent magnet elements, each partly enclosed in a separate magnetic element that has temperature-responsive variable permeability, is provided for attachment to the wall of a color cathode ray tube to compensate for beam mislanding on the color phosphor screen caused by thermal expansion of a beam selecting mask in the tube. The avoidance of mislanding is necessary to maintain fine color purity of color television images produced by the tube.
Inventors
- 👤 Hiromasa Machida
- 👤 Hiroshi Ichigaya
- 👤 Kietsu Iwabuchi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 10:21
CPC Classifications
H; H01; H01J; H01J29/00; H01J29/006; H01J29/46; H01J29/70; H01J29/701
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
160 words
In combination with a color cathode ray tube having an envelope with a screen at one end thereof composed of arrays of different color phosphors, and in which electron beams are made to scan said screen for impingement on the respective color phosphors thereof; an arrangement for correcting temperature induced mislanding of said electron beams in respect to said respective color phosphors comprising elongated strap means of relatively high magnetic permeability, and temperature-responsive magnetic flux generating means attached to the opposite ends of said strap means and being effective to produce magnetic fields which vary in intensity with varying temperature and which are spread by said strap means, said strap means and magnetic flux generating means being disposed against said envelope of the cathode ray tube so that said magnetic flux generating means are influenced by the temperature of said tube and said magnetic fields act within the latter on said electron beams for correcting said temperature induced mislanding thereof.
Claim 2
Dependent Claim
160 words
In combination with a color cathode ray tube having an envelope with a screen at one end thereof composed of arrays of different color phosphors, and in which electron beams are made to scan said screen for impingement on the respective color phosphors thereof; an arrangement for correcting temperature induced mislanding of said electron beams in respect to said respective color phosphors comprising elongated strap means of relatively high magnetic permeability, and temperature-responsive magnetic flux generating means attached to the opposite ends of said strap means and being effective to produce magnetic fields which vary in intensity with varying temperature and which are spread by said strap means, said strap means and magnetic flux generating means being disposed against said envelope of the cathode ray tube so that said magnetic flux generating means are influenced by the temperature of said tube and said magnetic fields act within the latter on said electron beams for correcting said temperature induced mislanding thereof.
Claim 3
Dependent Claim
84 words
The Combination according to claim 1; in which said strap means includes two straps of said relatively high magnetic permeability and each having said magnetic flux generating means attached to said opposite ends thereof, said envelope has a funnel-shaped portion leading to said screen, and said two straps and the respective magnetic flux generating means are disposed on said funnel-shaped portion at opposite sides of the center of the tube with said straps extending substantially normal to the line scanning direction of said beams.
Claim 4
Dependent Claim
27 words
The combination according to claim 1; in which a portion of each of said magnetic flux generating means extends beyond the respective end of said strap means.
Claim 5
Dependent Claim
15 words
The combination according to claim 1; in which said strap means is of silicon steel.
Claim 6
Dependent Claim
14 words
The combination according to claim 1; in which said strap means is of Permalloy.
Claim 7
Dependent Claim
100 words
The combination according to claim 1; in which each of said magnetic flux generating means includes a permanent magnet having north and south poles disposed at opposed portions thereof, and a shunt member attached to the respective end of said strap means and in which said permanent magnet is mounted so that the permanent magnets of said magnetic flux generating means at the opposite ends of said strap means have their north and south poles, respectively, directed toward each other; and in which each said shunt member is of a material having its magnetic permeability varied with changes in temperature.
Claim 8
Dependent Claim
72 words
The combination according to claim 6; in which each said permanent magnet has a non-circular periphery to which the locations of said north and south poles have a predetermined relationship, and each said shunt member has a recess shaped to receive the respective permanent magnet and to ensure the proper positional relationship of said poles of the magnets in said magnetic flux generating means at the opposite ends of said strap means.
Claim 9
Dependent Claim
50 words
The combination according to claim 6; in which said north and south poles of the magnets which are directed toward each other are in overlapping relation to the respective ends of said strap means, and the other poles of said magnets project beyond said respective ends of the strap means.
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) | 1978-03-24 | 1978-09-23 | 1979-03-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-03-24 | 1982-09-23 | 1983-03-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-03-24 | 1986-09-23 | 1987-03-25 | $7700.00 | Window Closed / Lapsed |