US5404084A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of and apparatus for canceling electric field
Assignee: Sony Corp
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Filing: 1993-12-28
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Granted: 1995-04-04
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Expires: 2013-12-28
Abstract
Abstract An electric field cancellation apparatus that can reduce electric field radiation from a cathode ray tube inexpensively includes a canceling pulse generating circuit generating a pulse voltage that cancels a leaked electric field radiated from a high voltage generating circuit employed with a deflection circuit or the like. The canceling pulse voltage is superimposed upon an output voltage of the high voltage generating circuit and is applied through an anode to an aperture grill of the cathode ray tube, whereby an electric field having a phase opposite to that of the leaked electric field is radiated from the whole surface of the aperture grill, so that the leaked electric field radiated from the cathode ray tube can be canceled.
Inventors
- 👤 Toshio Onodera
- 👤 Kazuaki Hoshino
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 21:34
CPC Classifications
H; H01; H01J; H01J29/00; H01J29/003; H04; H04N; H04N5/00; H04N5/64; H04N5/65; H01J2229/00; H01J2229/0007; H01J2229/0015
Claims Analysis
Total Claims: 22
Claim 1
Independent Claim
142 words
An electric field cancellation apparatus for a cathode ray tube display comprising: a deflection yoke for deflecting an electron beam in said cathode ray tube in response to a pulsed deflection signal; a deflection circuit for supplying said deflection signal to said deflection yoke; a high voltage generating circuit for generating a high voltage signal fed to said cathode ray tube; a canceling pulse generating circuit for generating canceling pulses having a polarity opposite to a polarity of pulses of said pulsed deflection signal and superimposed on said high voltage signals for cancelling an electric field emission; and means for supplying said canceling pulse superimposed on said high voltage signal to an anode of said cathode ray tube, wherein said canceling pulse supplied to said anode of said cathode ray tube is connected to an aperture grill of said cathode ray tube.
Claim 2
Dependent Claim
142 words
An electric field cancellation apparatus for a cathode ray tube display comprising: a deflection yoke for deflecting an electron beam in said cathode ray tube in response to a pulsed deflection signal; a deflection circuit for supplying said deflection signal to said deflection yoke; a high voltage generating circuit for generating a high voltage signal fed to said cathode ray tube; a canceling pulse generating circuit for generating canceling pulses having a polarity opposite to a polarity of pulses of said pulsed deflection signal and superimposed on said high voltage signals for cancelling an electric field emission; and means for supplying said canceling pulse superimposed on said high voltage signal to an anode of said cathode ray tube, wherein said canceling pulse supplied to said anode of said cathode ray tube is connected to an aperture grill of said cathode ray tube.
Claim 3
Dependent Claim
142 words
An electric field cancellation apparatus for a cathode ray tube display comprising: a deflection yoke for deflecting an electron beam in said cathode ray tube in response to a pulsed deflection signal; a deflection circuit for supplying said deflection signal to said deflection yoke; a high voltage generating circuit for generating a high voltage signal fed to said cathode ray tube; a canceling pulse generating circuit for generating canceling pulses having a polarity opposite to a polarity of pulses of said pulsed deflection signal and superimposed on said high voltage signals for cancelling an electric field emission; and means for supplying said canceling pulse superimposed on said high voltage signal to an anode of said cathode ray tube, wherein said canceling pulse supplied to said anode of said cathode ray tube is connected to a shadow mask of said cathode ray tube.
Claim 4
Dependent Claim
142 words
An electric field cancellation apparatus for a cathode ray tube display comprising: a deflection yoke for deflecting an electron beam in said cathode ray tube in response to a pulsed deflection signal; a deflection circuit for supplying said deflection signal to said deflection yoke; a high voltage generating circuit for generating a high voltage signal fed to said cathode ray tube; a canceling pulse generating circuit for generating canceling pulses having a polarity opposite to a polarity of pulses of said pulsed deflection signal and superimposed on said high voltage signals for cancelling an electric field emission; and means for supplying said canceling pulse superimposed on said high voltage signal to an anode of said cathode ray tube, wherein said canceling pulse supplied to said anode of said cathode ray tube is connected to a shadow mask of said cathode ray tube.
Claim 5
Dependent Claim
29 words
An electric field cancellation apparatus for a cathode ray tube display as claimed in claim 1, wherein said canceling pulse generating circuit comprises a winding of a flyback transformer.
Claim 6
Dependent Claim
31 words
An electric field cancellation apparatus for a cathode ray tube display as claimed in claim 1, further comprising capacitor means whereby said canceling pulse is supplied to said cathode ray tube.
Claim 7
Dependent Claim
146 words
An electric field cancellation apparatus for a cathode ray tube display comprising: a deflection yoke for deflecting an electron beam in said cathode ray tube in response to a pulsed deflection signal; a deflection circuit for supplying said deflection signal to said deflection yoke; a high voltage generating circuit for generating a high voltage signal fed to said cathode ray tube; a canceling pulse generating circuit for generating canceling pulses having a polarity opposite to a polarity of pulses of said pulsed deflection signal and superimposed on said high voltage signal for cancelling an electric field emission; means for superimposing said canceling pulse on said high voltage signal; tube; capacitor means for supplying said cancelling pulse superimposed on said high voltage signal to an anode of said cathode ray tube; and a differential circuit whereby said canceling pulse is differentiated and supplied to said capacitor means.
Claim 8
Dependent Claim
146 words
An electric field cancellation apparatus for a cathode ray tube display comprising: a deflection yoke for deflecting an electron beam in said cathode ray tube in response to a pulsed deflection signal; a deflection circuit for supplying said deflection signal to said deflection yoke; a high voltage generating circuit for generating a high voltage signal fed to said cathode ray tube; a canceling pulse generating circuit for generating canceling pulses having a polarity opposite to a polarity of pulses of said pulsed deflection signal and superimposed on said high voltage signal for cancelling an electric field emission; means for superimposing said canceling pulse on said high voltage signal; tube; capacitor means for supplying said cancelling pulse superimposed on said high voltage signal to an anode of said cathode ray tube; and a differential circuit whereby said canceling pulse is differentiated and supplied to said capacitor means.
Claim 9
Dependent Claim
48 words
An electric field cancellation apparatus for a cathode ray tube display as claimed in claim 5, wherein said differential circuit comprises a differential capacitor, a diode connected in series to said differential capacitor and first and second resistors connected respectively between both ends of said diode and ground.
Claim 10
Dependent Claim
28 words
An electric field cancellation apparatus for a cathode ray tube display as claimed in claim 1, wherein said canceling pulse generating circuit includes a horizontal deflection signal generator.
Claim 11
Dependent Claim
37 words
An electric field cancellation apparatus for a cathode ray tube display as claimed in claim 7, wherein said canceling pulse is derived from a secondary winding of a horizontal output transformer of said horizontal deflection signal generator.
Claim 12
Dependent Claim
31 words
An electric field cancellation apparatus for a cathode ray tube display as claimed in claim 7, further comprising capacitor means whereby said canceling pulse is supplied to said cathode ray tube.
Claim 13
Dependent Claim
138 words
An electric field cancellation apparatus for a cathode ray tube display comprising: a deflection yoke for deflecting an electron beam in said cathode ray tube in response to a pulsed deflection signal; a deflection circuit for supplying said deflection signal to said deflection yoke; a high voltage generating circuit for generating a high voltage signal fed to said cathode ray tube; a canceling pulse generating circuit for generating canceling pulses having a polarity opposite to a polarity of pulses of said pulsed deflection signal and superimposed on said high voltage signals for cancelling an electric field emission, wherein said canceling pulse generating circuit includes a horizontal deflection signal generator; capacitor means, whereby said canceling pulse is supplied to said cathode ray tube; and a differential circuit whereby said canceling pulse is differentiated and supplied to said capacitor means.
Claim 14
Dependent Claim
138 words
An electric field cancellation apparatus for a cathode ray tube display comprising: a deflection yoke for deflecting an electron beam in said cathode ray tube in response to a pulsed deflection signal; a deflection circuit for supplying said deflection signal to said deflection yoke; a high voltage generating circuit for generating a high voltage signal fed to said cathode ray tube; a canceling pulse generating circuit for generating canceling pulses having a polarity opposite to a polarity of pulses of said pulsed deflection signal and superimposed on said high voltage signals for cancelling an electric field emission, wherein said canceling pulse generating circuit includes a horizontal deflection signal generator; capacitor means, whereby said canceling pulse is supplied to said cathode ray tube; and a differential circuit whereby said canceling pulse is differentiated and supplied to said capacitor means.
Claim 15
Dependent Claim
48 words
An electric field cancellation apparatus for a cathode ray tube display as claimed in claim 10, wherein said differential circuit comprises a differential capacitor, a diode connected in series with said differential capacitor, and first and second resistors connected respectively between both ends of said diode and ground.
Claim 16
Dependent Claim
38 words
An electric field cancellation apparatus for a cathode ray tube display as claimed in claim 9, wherein said canceling pulse through said capacitor means is supplied to said cathode ray tube at an output of a flyback transformer.
Claim 17
Independent Claim
76 words
A method of canceling a leaked electric field for a cathode ray tube display comprising the steps of: generating a canceling signal from a high voltage signal; supplying said canceling signal to a cathode ray tube through a capacitor; emitting an electric field inverse to the unwanted electric field from a part of said cathode ray tube; and differentially processing said canceling signal before supplying said canceling signal to said cathode ray tube through said capacitor.
Claim 18
Independent Claim
76 words
A method of canceling a leaked electric field for a cathode ray tube display comprising the steps of: generating a canceling signal from a high voltage signal; supplying said canceling signal to a cathode ray tube through a capacitor; emitting an electric field inverse to the unwanted electric field from a part of said cathode ray tube; and differentially processing said canceling signal before supplying said canceling signal to said cathode ray tube through said capacitor.
Claim 19
Dependent Claim
41 words
A method of cancelling an unwanted electric field for a cathode ray tube display as claimed in claim 13, comprising the further step of inverting a phase of said emitting electric field relative to a phase of the leaked electric field.
Claim 20
Independent Claim
76 words
A method of canceling a leaked electric field for a cathode ray tube display comprising the steps of: generating a canceling signal from a horizontal deflection signal; supplying said canceling signal to the cathode ray tube through a capacitor; emitting an electric field inverse to the unwanted electric field from a part of said cathode ray tube; and differentially processing said canceling signal before supplying said canceling signal to said cathode ray tube through said capacitor.
Claim 21
Independent Claim
76 words
A method of canceling a leaked electric field for a cathode ray tube display comprising the steps of: generating a canceling signal from a horizontal deflection signal; supplying said canceling signal to the cathode ray tube through a capacitor; emitting an electric field inverse to the unwanted electric field from a part of said cathode ray tube; and differentially processing said canceling signal before supplying said canceling signal to said cathode ray tube through said capacitor.
Claim 22
Dependent Claim
41 words
A method of canceling a leaked electric field for a cathode ray tube display as claimed in claim 15, comprising the further step of inverting a phase of said emitting electric field relative to a phase of the leaked electric field.
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) | 1998-04-03 | 1998-10-03 | 1999-04-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2002-04-03 | 2002-10-03 | 2003-04-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2006-04-03 | 2006-10-03 | 2007-04-04 | $7700.00 | Window Closed / Lapsed |