US3629653A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Crossed grid el display driver technique
Assignee: Sycon Corp
•
Filing: 1970-03-23
•
Granted: 1971-12-21
•
Expires: 1990-03-23
Abstract
Abstract Variable brightness, crossed grid, electroluminescent panel driving circuitry and logic means are described wherein the brightness of a selected cell is controlled by the length of driver circuit input pulse. The length of the input pulse is controlled by logic means.
Inventors
- 👤 Munt Irwin
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 15:52
CPC Classifications
H; H04; H04N; H04N3/00; H04N3/10; H04N3/14; G; G09; G09G; G09G3/00; G09G3/20; G09G3/22; G09G3/30; H05; H05B; H05B47/00; H05B47/10; H05B47/155
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
170 words
A variable brightness electroluminescent device comprising: first and second spaced electrodes with electroluminescent material therebetween and characterized by a predetermined capacitance; first driver means comprising inductive means connected to said first electrode and operative in response to a first and second coincident pulses having a predetermined reference length to provide an alternating current voltage to said first electrode of a frequency determined by the capacitance of the cell and the inductance of said inductive means; and second driver means comprising inductive means connected to said first electrode and operative in response to a third coincident pulse having said reference length and to a fourth pulse which starts in coincidence with said first, second, and third pulses but has a length which is less than said reference length to provide a second alternating current voltage to said second electrode, the peaks of which second alternating current voltage are out of phase with respect to said first alternating current voltage by an amount which varies with said length of said fourth pulse.
Claim 2
Dependent Claim
170 words
A variable brightness electroluminescent device comprising: first and second spaced electrodes with electroluminescent material therebetween and characterized by a predetermined capacitance; first driver means comprising inductive means connected to said first electrode and operative in response to a first and second coincident pulses having a predetermined reference length to provide an alternating current voltage to said first electrode of a frequency determined by the capacitance of the cell and the inductance of said inductive means; and second driver means comprising inductive means connected to said first electrode and operative in response to a third coincident pulse having said reference length and to a fourth pulse which starts in coincidence with said first, second, and third pulses but has a length which is less than said reference length to provide a second alternating current voltage to said second electrode, the peaks of which second alternating current voltage are out of phase with respect to said first alternating current voltage by an amount which varies with said length of said fourth pulse.
Claim 3
Dependent Claim
43 words
A variable brightness electroluminescent device as defined in claim 1, and further comprising: logic means for generating said fourth pulse in response to a start signal and so as to have a length corresponding to brightness level input signals to said logic means.
Claim 4
Dependent Claim
145 words
A variable brightness electroluminescent device as defined in claim 2, and wherein said logic means comprises: clock means for generatinG clock pulses at a predetermined frequency; AND-gate means connected to receive said clock pulses as a first input thereto; flip-flop means having first and second states and responsive to initiate said fourth pulse as the second state output thereof; said AND-gate means being responsive to said second state of said flip-flop means to pass said clock pulses as an output of said AND-gate means; register means connected to receive said clock pulses from said AND-gate means and conditioned by said brightness level input signals to provide an output signal when a predetermined number of said clock pulses have been received; and said flip-flop means being responsive to said output signal of said register means to return to said first state and terminate said fourth pulse.
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) | 1974-12-20 | 1975-06-21 | 1975-12-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-12-20 | 1979-06-21 | 1979-12-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-12-20 | 1983-06-21 | 1983-12-21 | $7700.00 | Window Closed / Lapsed |