Patent US3611024A successfully refreshed from Google Patents.
US3611024A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Semiconductor apparatus for controlling the brightness of a discharge lamp
Assignee: Panasonic Holdings Corp
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Filing: 1969-07-17
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Granted: 1971-10-05
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Expires: 1989-07-17
Abstract
Abstract A fluorescent lamp lighting apparatus which comprises a DC fluorescent discharge lamp having one hot negative electrode and two positive electrodes, a first DC source for constantly generating a glow discharge between said negative electrode and one of said positive electrodes, a second DC source for generating an arc discharge between said negative electrode and another one of said positive electrodes, and semiconductor control means for intermittently interrupting the power supply from said second DC source to the discharge lamp and controlling the magnitude of its voltage, said semiconductor control means being used for on-off control of the fluorescent discharge lamp and for brilliance modulation of the same in response to a video signal of a television signal; and which enables the blinking frequency of the fluorescent discharge lamp to be reduced to several tens of microseconds to several hundreds of microseconds and can be used as a light source for display apparatus.
Inventors
- 👤 Hiromasa Nakatsu
- 👤 Takeshige Ichida
- 👤 Teruhisa Kaneko
- 👤 Sadao Matsumoto
- 👤 Tokuyuki Wakiyama
- 👤 Kenzi Murata
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 07:48
CPC Classifications
H; H05; H05B; H05B41/00; H05B41/02; H05B41/04; H05B41/042; H05B41/044; H05B41/046; Y; Y10; Y10S; Y10S315/00; Y10S315/01; Y10S315/04; Y10S315/07
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
89 words
A discharge lamp lighting apparatus as defined in claim 1, in which said control means is composed of a switching element, a unidirectional thyristor having a gate electrode and connected in series with said switching element, a gate signal generator for controlling the state of energization of said switching element, and a pulse generator connected between the gate and the cathode of said unidirectional thyristor for controlling the conduction of said unidirectional thyristor, the power being supplied to the discharge lamp intermittently through said switching element and said thyristor.
Claim 2
Dependent Claim
161 words
A discharge lamp lighting apparatus as defined in claim 1, in which said control means is composed of a diode, a capacitor for accumulating and holding a signal impressed thereon through said diode, a unidirectional thyristor connected in parallel with said capacitor and having a gate electrode to receive an external trigger signal, and a transistor amplifier having emitter and collector electrodes connected to the other one of said positive electrodes and said second direct-current power source respectively and having a base electrode connected to said capacitor, the state of conduction of said transistor amplifier being controlled by a voltage developed across the terminals of said capacitor, said transistor amplifier controlling the discharge current of the discharge lamp in response to the external signal voltage throughout the period when the signal is held by said capacitor, and said unidirectional thyristor being triggered to be turned on to eliminate the signal held in said capacitor and thereby turn off the fluorescent lamp.
Claim 3
Dependent Claim
141 words
A discharge lamp lighting apparatus as defined in claim 1, in which said control means is composed of a diode, a capacitor for accumulating a signal supplied thereto through said diode, a resistor connected in parallel with said capacitor, a transistor amplifier having a base electrode connected to said capacitor for amplifying a voltage developed across the terminals of said capacitor by the discharge current of the capacitor flowing through said resistor, a voltage regulating means connected to an output terminal of said trAnsistor amplifier, a switching transistor having a base electrode connected to said voltage regulating means and having collector and emitter electrodes connected to the other one of said positive electrodes of said discharge lamp and said second direct-current power source respectively, said switching transistor being operable to interrupt the current supply from said second direct-current power source intermittently.
Claim 4
Dependent Claim
44 words
A discharge lamp lighting apparatus as defined in claim 1, in which said control means including parallel-connected capacitor and capacitor-discharging-path means, and having an input terminal connected to said capacitor for receiving an external signal to thereby charge said capacitor from said external signal.
References Cited (Backward Citations)
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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) | 1974-10-04 | 1975-04-05 | 1975-10-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-10-04 | 1979-04-05 | 1979-10-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-10-04 | 1983-04-05 | 1983-10-05 | $7700.00 | Window Closed / Lapsed |