US3889151A
Expired / Lapsed
US
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Energizing technique for electroluminescent devices
Assignee: RCA Corp
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Filing: 1973-08-02
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Granted: 1975-06-10
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Expires: 1993-08-02
Abstract
Abstract An energizing voltage provided by a DC voltage source in series with a pulse generator provides unexpectedly high brightness of light emitted from an electroluminescent device. The DC voltage in itself has a magnitude which results in insignificantly small current through and light emission by the electroluminescent device, which may have a non-linear current-voltage characteristic.
Inventors
- 👤 Joseph John Hanak
- 👤 Peter David Southgate
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 19:48
CPC Classifications
H; H05; H05B; H05B44/00; Y; Y02; Y02B; Y02B20/00; Y02B20/30
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
164 words
The combination comprising: a. a given electroluminescent device having a non-linear current-voltage characteristic that a first voltage there across having a first level of a given polarity results in an insignificantly small current therethrough and an insignificant brightness of light emitted thereby and a second voltage thereacross having a second level of said given polarity which is higher than said first level results in a significantly large current therethrough and a significant brightness of light emitted therby, and b. power supply means coupled across said device, including a DC voltage supply and a pulse generator connected in series with each othEr, said DC voltage supply supplying a continuous DC voltage magnitude of said first level and given polarity, and said pulse generator generating a series of intermittent DC pulses at a given duty cycle which is not in excess of one percent, with each pulse having said given polarity and an amplitude equal to the difference between said second level and said first level.
Claim 2
Dependent Claim
164 words
The combination comprising: a. a given electroluminescent device having a non-linear current-voltage characteristic that a first voltage there across having a first level of a given polarity results in an insignificantly small current therethrough and an insignificant brightness of light emitted thereby and a second voltage thereacross having a second level of said given polarity which is higher than said first level results in a significantly large current therethrough and a significant brightness of light emitted therby, and b. power supply means coupled across said device, including a DC voltage supply and a pulse generator connected in series with each othEr, said DC voltage supply supplying a continuous DC voltage magnitude of said first level and given polarity, and said pulse generator generating a series of intermittent DC pulses at a given duty cycle which is not in excess of one percent, with each pulse having said given polarity and an amplitude equal to the difference between said second level and said first level.
Claim 3
Dependent Claim
34 words
The combination defined in claim 1, wherein said first level DC voltage has a magnitude sufficient by itself to provide an electric field across said device in the order of seventy-five volts per micrometer.
Claim 4
Dependent Claim
28 words
The combination defined in claim 2, wherein said electroluminescent device comprises a film about two micrometers thick and said first level DC voltage is substantially one-hundred fifty volts.
Claim 5
Dependent Claim
25 words
The combination defined in claim 3, wherein said film is a zinc sulfide host doped with an activator element forming a suitable light emitting center.
Claim 6
Dependent Claim
19 words
The combination defined in claim 3, wherein said second level voltage is between two-hundred sixty volts and three-hundred volts.
Claim 7
Dependent Claim
29 words
The combination defined in claim 3, wherein said second level voltage is substantially three-hundred volts and each pulse has a duration in the range of one to twenty microseconds.
Claim 8
Dependent Claim
30 words
The combination defined in claim 3, wherein said second level voltage is substantially two-hundred eighty volts and each pulse has a duration in the range of one to one-hundred microseconds.
Claim 9
Dependent Claim
30 words
The combination defined in claim 3, wherein said second level voltage is substantially two-hundred sixty volts and each pulse has a duration in the range of three to one-hundred microseconds.
Claim 10
Dependent Claim
50 words
The combination defined in claim 1, wherein said brightness is at a maximum when said pulses each have a duration equal to a given value at said given duty cycle, and wherein each of the pulses generated by said pulse generator has a duration substantially equal to said given value.
Claim 11
Dependent Claim
20 words
The combination defined in claim 1, wherein said given duty cycle is in the order of one-tenth of one percent.
Claim 12
Independent Claim
63 words
A method for energizing an electroluminescent device comprising the step of: applying an energizing voltage across said device composed of a series of DC pulses of given amplitude and given polarity occurring at a given duty cycle which is not in excess of one percent, said series of pulses riding on a continuous DC pedestal of a given magnitude and said given polarity.
Claim 13
Independent Claim
63 words
A method for energizing an electroluminescent device comprising the step of: applying an energizing voltage across said device composed of a series of DC pulses of given amplitude and given polarity occurring at a given duty cycle which is not in excess of one percent, said series of pulses riding on a continuous DC pedestal of a given magnitude and said given polarity.
Claim 14
Dependent Claim
38 words
The method defined in claim 11, wherein the brightness of light emitted from said device is a maximum when the duration of each said pulses has a given value, and wherein said duration has substantially said given value.
References Cited (Backward Citations)
US2972692A
Cited
US3710181A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-06-09 | 1978-12-09 | 1979-06-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-06-09 | 1982-12-09 | 1983-06-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-06-09 | 1986-12-09 | 1987-06-10 | $7700.00 | Window Closed / Lapsed |