Patent US3902185A successfully refreshed from Google Patents.
US3902185A
Expired / Lapsed
US
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Image signal processing device
Assignee: Panasonic Holdings Corp
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Filing: 1973-01-19
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Granted: 1975-08-26
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Expires: 1993-01-19
Abstract
Abstract An image signal processing device is made up of a plurality of sets of series connected elements each of said sets consisting essentially of, in the recited order, a first transparent electrode element; an electricity-to-light conversion element having an electrical resistance R; a negative resistance element having a voltage-current curve which has a transition point from a portion of high resistance Rh to a portion of low resistance Rl at a critical voltage Vc; a light-to-electricity conversion element having electrical resistance R1 and R2 when irradiated with light having intensities L1 and L2, respectively, where L1 is lower than and L2 is higher than a critical intensity Lc which causes the negative resistance element in each of the series connections to receive a voltage above or below the critical voltage Vc, respectively when each of the series connections is provided with a given voltage V; and a second transparent electrode element. When the light to electricity conversion elements are irradiated with a light image and the given voltage V is applied to the device, each electricity-to-light conversion element is energized by a voltage RV/(R+R1+Rh) or RV/R+R2+Rl) when the light-to-electricity conversion element is irradiated with the light intensity L1 or L2, and accordingly the light image has the contrast increased.
Inventors
- 👤 Shigeru Hayakawa
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 10:31
CPC Classifications
H; H10; H10F; H10F55/00; H10F55/10
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
203 words
AN IMAGE SIGNAL PROCESSING DEVICE COMPRISING A PLURALITY OF SETS OF SERIES CONNECTED ELEMENTS, EACH OF SAID SETS COMPRISING, IN THE RECITED ORDER, A FIRST TRANSPARENT ELECTRODE ELEMENT, AN ELECTRICITY-TO-LIGHT CONVERSION ELEMENT HAVING AN ELECTRICAL RESISTANCE R, A NEGTIVE RESISTANCE ELEMENT HAVING A VOLTAGECURRENT CURVE WHICH HAS A TRANSITION POINT FROM A PORTION OF HIGH RESISTANCE RH TO A PORTION OF LOW RESISTENCE RL AT A CRITICAL VOLTAGE VC, A LIGHT-TO-ELECTRICITY CONVERSION ELEMENT HAVING ELECTRICAL RESISTANCES R1 AND R2 WHEN IRRADIATED WITH LIGHT HAVING INTENSITIES L1 AND L2, RESPECTIVELY, WHERE L1 IS LOWER THAN AND L2 IS HIGHER THAN A ERITICAL INTENSITY LC WHICH CAUSES SAID NEGATIVE RESISTANCE ELEMENT IN EACH OF SAID SERIES CONNECTIONS TO RECEIVE A VOLTAGE ABOVE OR BELOW SAID CRITICAL VOLTAGE VC, RESPECTIVELY, WHEN EACH OF SAID SERIES CONNECTION IS PROVIDED WITH A GIVEN VOLTAGE V, AND A SECOND TRANSPARENT ELECTRODE ELEMENT, WHEREBY WHEN SAID LIGHT-TO-ELECTRICITY CONVERSION ELEMENTS ARE IRRADIATED WITH A LIGHT IMAGE AND SAID GIVEN VOLTAGE V IS APPLIED TO SAID DEVICE, EACH ELECTRICITY-TO-LIGHT CONVERSION ELEMENT IS ENERGIZED BY A VOLTAGE RV/R+R1+RH) OR RV/(R+R2+RL) WHEN SAID LIGHT-TO-ELECTRICITY CONVERSION ELEMENT IS IRRADATED WITH THE LIGHT INTENSITY L1 OR L2, AND, ACCORDINLY, AND LIGHT IMAGE HAS THE CONTRAST INCREASED.
Claim 2
Dependent Claim
203 words
AN IMAGE SIGNAL PROCESSING DEVICE COMPRISING A PLURALITY OF SETS OF SERIES CONNECTED ELEMENTS, EACH OF SAID SETS COMPRISING, IN THE RECITED ORDER, A FIRST TRANSPARENT ELECTRODE ELEMENT, AN ELECTRICITY-TO-LIGHT CONVERSION ELEMENT HAVING AN ELECTRICAL RESISTANCE R, A NEGTIVE RESISTANCE ELEMENT HAVING A VOLTAGECURRENT CURVE WHICH HAS A TRANSITION POINT FROM A PORTION OF HIGH RESISTANCE RH TO A PORTION OF LOW RESISTENCE RL AT A CRITICAL VOLTAGE VC, A LIGHT-TO-ELECTRICITY CONVERSION ELEMENT HAVING ELECTRICAL RESISTANCES R1 AND R2 WHEN IRRADIATED WITH LIGHT HAVING INTENSITIES L1 AND L2, RESPECTIVELY, WHERE L1 IS LOWER THAN AND L2 IS HIGHER THAN A ERITICAL INTENSITY LC WHICH CAUSES SAID NEGATIVE RESISTANCE ELEMENT IN EACH OF SAID SERIES CONNECTIONS TO RECEIVE A VOLTAGE ABOVE OR BELOW SAID CRITICAL VOLTAGE VC, RESPECTIVELY, WHEN EACH OF SAID SERIES CONNECTION IS PROVIDED WITH A GIVEN VOLTAGE V, AND A SECOND TRANSPARENT ELECTRODE ELEMENT, WHEREBY WHEN SAID LIGHT-TO-ELECTRICITY CONVERSION ELEMENTS ARE IRRADIATED WITH A LIGHT IMAGE AND SAID GIVEN VOLTAGE V IS APPLIED TO SAID DEVICE, EACH ELECTRICITY-TO-LIGHT CONVERSION ELEMENT IS ENERGIZED BY A VOLTAGE RV/R+R1+RH) OR RV/(R+R2+RL) WHEN SAID LIGHT-TO-ELECTRICITY CONVERSION ELEMENT IS IRRADATED WITH THE LIGHT INTENSITY L1 OR L2, AND, ACCORDINLY, AND LIGHT IMAGE HAS THE CONTRAST INCREASED.
Claim 3
Dependent Claim
20 words
An image signal processing device defined in claim 1, wherein said electricity-to-light conversion element consists essentially of an electroluminescent material.
Claim 4
Dependent Claim
21 words
An image signal processing device defined by claim 1, wherein said electricity-to-light conversion element consists essentially of a light emitting diode.
Claim 5
Dependent Claim
38 words
An image signal processing device defined by claim 1, wherein said negative resistance element consists essentially of one element selected from the group consisting of a switching diode and a thermistor having a negative temperature coefficient of resistance.
Claim 6
Dependent Claim
20 words
An image signal processing device defined by claim 1, wherein said light-to-electricity conversion element consists essentially of a photoconductive material.
Claim 7
Dependent Claim
72 words
An image signal processing device defined by claim 1 wherein said series connected elements are in a panel including a transparent base, a first transparent electrode layer on said transparent base, an electroluminescent layer integrally formed on said first transparent electrode layer, a negative resistance layer integrally formed on said electroluminescent layer, a photoconductive layer superposed on said negative resistance layer, and a second transparent electrode layer superposed on said photoconductive layer.
Claim 8
Dependent Claim
37 words
An image signal prOcessing device defined by claim 6, wherein said negative resistance layer consists essentially of a thermistor layer comprising finely divided powder dispersed in a binding material and having a negative temperature coefficient of resistance.
Claim 9
Dependent Claim
30 words
An image signal processing device defined by claim 7, wherein said thermistor layer has a heating element embedded therein so as to control the size of said critical voltage Vc.
Claim 10
Dependent Claim
62 words
An image signal processing device comprising a first transparent electrode element, and electricity-to-light conversion element on said first transparent electrode element, a light-to-electricity conversion element integrally formed on said electricity-to-light conversion element, and a second transparent electrode element on said light-to-electricity conversion element, and a switching transistor connected to one of said first transparent electrode element and said second transparent electrode element.
Claim 11
Dependent Claim
62 words
An image signal processing device comprising a first transparent electrode element, and electricity-to-light conversion element on said first transparent electrode element, a light-to-electricity conversion element integrally formed on said electricity-to-light conversion element, and a second transparent electrode element on said light-to-electricity conversion element, and a switching transistor connected to one of said first transparent electrode element and said second transparent electrode element.
Claim 12
Dependent Claim
26 words
An image signal processing device defined by claim 9, wherein said electricity-to-light conversion element and said light-to-electricity conversion element have a light preventing element sandwitched therebetween.
Claim 13
Dependent Claim
35 words
An image signal processing device defined by claim 9, wherein said switching transistor is biased between the emitter and the base so as to control the size of the critical voltage Vc of said device.
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) | 1978-08-25 | 1979-02-24 | 1979-08-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-08-25 | 1983-02-24 | 1983-08-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-08-25 | 1987-02-24 | 1987-08-26 | $7700.00 | Window Closed / Lapsed |