US3811066A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Television camera comprising an interference-free mesh connection conductor
Assignee: US Philips Corp
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Filing: 1973-01-05
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Granted: 1974-05-14
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Expires: 1993-01-05
Abstract
Abstract In order to suppress interference signals caused by the line deflection field across the capacitive interruption between the mesh electrode and the target, the mesh connection loop of a television camera having a separated mesh electrode is constructed such that effectively it encloses substantially no magnetic flux of the line deflection field. The return field which is usually concentrated in the wall of a ferromagnetic screening bush mounted about the camera tube is taken into account in this respect. In a preferred embodiment, the mesh connection wire in the camera tube has the shape of a helix having a pitch which corresponds to the axial field length of the line deflection field.
Inventors
- 👤 B Holman
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 16:59
CPC Classifications
H; H01; H01J; H01J29/00; H01J29/92; H01J29/003; H01J29/02; H01J29/021; H01J29/86; H01J29/867; H01J31/00; H01J31/08; H01J31/26; H01J31/28; H01J31/34; H01J31/38
Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
130 words
A television camera comprising a television camera tube having an envelope with a target to be scanned by an electron beam therein and a mesh electrode positioned in proximity to the target, means to produce a line deflection field for scanning said target line-wise with said electron beam, and means to apply a direct voltage between the mesh electrode and the target, said latter means comprising a conductor within the tube envelope and a conductor external to the tube envelope, said conductors being connected to said mesh electrode and forming a loop having a configuration which avoids the appearance of interference voltages, caused by the line deflection field, between the mesh electrode and the target and prevents the appearance of disturbing induction currents in the conductor within the tube envelope.
Claim 2
Dependent Claim
130 words
A television camera comprising a television camera tube having an envelope with a target to be scanned by an electron beam therein and a mesh electrode positioned in proximity to the target, means to produce a line deflection field for scanning said target line-wise with said electron beam, and means to apply a direct voltage between the mesh electrode and the target, said latter means comprising a conductor within the tube envelope and a conductor external to the tube envelope, said conductors being connected to said mesh electrode and forming a loop having a configuration which avoids the appearance of interference voltages, caused by the line deflection field, between the mesh electrode and the target and prevents the appearance of disturbing induction currents in the conductor within the tube envelope.
Claim 3
Dependent Claim
34 words
A television camera as claimed in claim 1, wherein the conductor within the tube envelope comprises a wire having a 180*-step at the area of the center, axially measured, of the line deflection field.
Claim 4
Dependent Claim
47 words
A television camera as claimed in claim 2, wherein the conductor within the tube envelope comprises two wires which are mounted within the tube envelope at an angle of 180* with respect to each other, each wire having a 180*-step at the area of the field center.
Claim 5
Dependent Claim
49 words
A television camera as claimed in claim 2, wherein the conductor within the tube envelope comprises two wires, each of which has a 180*-step at the area of the field center, the wires being mounted within the tube envelope at an angle of 90* with respect to each other.
Claim 6
Dependent Claim
39 words
A television camera as claimed in claim 1, wherein the conductor within the tube envelope comprises a wire having three steps of 90* each which divide the axially measured length of the line deflection field into four equal parts.
Claim 7
Dependent Claim
35 words
A television camera tube as claimed in claim 2, wherein the conductor within the tube envelope comprises a wire having n-1 steps of 360*/n which divide the axially measured field length into n equal pieces.
Claim 8
Dependent Claim
32 words
A television camera as claimed in claim 2, wherein the conductor within the tube envelope comprises a wire describing helix of 360* over the axially measured length of the line deflection field.
Claim 9
Dependent Claim
27 words
A television camera as claimed in claim 7, wherein the helical wire extends in the axial direction outside the area where the line deflection field is active.
Claim 10
Dependent Claim
33 words
A television camera as claimed in claim 7 wherein the conductor within the tube envelope comprises a helical wire having a pitch which is a sub-multiple of the axially but an field length.
Claim 11
Dependent Claim
34 words
A television camera as claimed in claim 7 wherein the conductor within the tube envelope comprises two helical wires having a common starting point and a common end point, butan opposed sense of rotation.
Claim 12
Dependent Claim
88 words
A television camera as claimed in claim 1 wherein the conductor within the tube envelope comprises a bushing which is connected to a tube base pin, a wire and a bushing which is connected to the mesh electrode, the bushings being arranged in the tube envelope at a mutual distance, viewed axially, of at the most the length of the area where the line deflection field is effective, the wire within the tube envelope forming a helix of 360* or an integral multiple of 360* between the bushinGs.
Claim 13
Dependent Claim
43 words
A television camera as claimed in claim 2 wherein the conductor within the tube envelope comprises a second wire extending in like manner to the first-mentioned wire and which is mounted in the tube envelope at an angle of 180* with respect thereto.
Claim 14
Dependent Claim
43 words
A television camera as claimed in claim 1, wherein the conductor within the tube envelope comprises at least three straight wires which are mounted at mutually equal distances, measured over the circumference of the tube envelope, without forming pairs of diametrically arranged wires.
Claim 15
Dependent Claim
77 words
A television camera as claimed in claim 1, wherein the loop comprises a wire within the envelope, both wires being arranged against the tube wall in a symmetry plane of the line deflection field at an as small as possible distance from each other, the wires being galvanically connected to each other on the tube base side, and making galvanic contact in the said sequence with the mesh electrode and a voltage source for the mesh electrode.
Claim 16
Dependent Claim
134 words
A television camera as claimed in claim 1 wherein the loop comprises, in addition to a wire within the tube envelope, a wire external to the tube envelope and which is axially mounted in a coil system for deflecting the electron beam, said wire external to the tube envelope being galvanically connected to the wire within the tube envelope at the base thereof and is galvanically connected to a voltage source on the tube window side, the wire within the tube envelope being situated in a plane which contains the axis of the system and which is transverse to the symmetry plane of the line deflection field, the wire external to the tube being situated in a plane which extends parallel to the line deflection field lines and through the wire within the tube.
Claim 17
Dependent Claim
35 words
A television camera as claimed in claim 1, wherein the conductor within the tube comprises two wires which are diametrically arranged in the tube envelope, an identical resistor being incorporated in each of these wires.
Claim 18
Dependent Claim
70 words
A television camera as claimed in claim 1, wherein the conductor within the tube envelope comprises two wires which are diametrically arranged within the tube envelope, each wire being connected to a passage pin in the tube base, the said tube base pins being connected, outside the camera tube, to a potentiometer resistor, one end of the gauze supply conductor being connected to the potentiometer resistor via a potentiometer wiper.
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) | 1977-05-13 | 1977-11-12 | 1978-05-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-05-13 | 1981-11-12 | 1982-05-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-05-13 | 1985-11-12 | 1986-05-14 | $7700.00 | Window Closed / Lapsed |