Patent US4945418A successfully refreshed from Google Patents.
US4945418A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Solid state image pickup apparatus with charge storage device
Assignee: Fujifilm Holdings Corp
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Filing: 1989-01-31
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Granted: 1990-07-31
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Expires: 2009-01-31
Abstract
Abstract A solid state image pickup device is provided in which a photodiode photoelectrically converts incident light to a voltage. Next a transistor performs voltage-to-current conversion, and a capacitor stores the charge. Current is stored in the capacitor without requiring the application of a reverse bias voltage to the photodiode. The voltage generated across the photodiode is logarithmically related to the quantity of incident light, and the dynamic range of the input signal to be reproduced is increased. As a result, dark current is minimized and dark current noise is reduced.
Inventors
- 👤 Hideki Mutoh
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 03:18
CPC Classifications
H; H04; H04N; H04N25/00; H04N25/60; H04N25/63; H04N25/70; H04N25/76; H04N25/77; H04N25/771
Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
78 words
A solid state image pickup device, comprising: a photodiode for receiving incident light and for performing photoelectric conversion of said incident light; a first transistor coupled to said photodiode for converting a voltage produced across said photodiode into an electric current; and a charge storage capacitor for storing an electric charge in response to said electric current, wherein said electric charge is stored in said charge storage capacitor with exclusive application of forwardly biased voltage to said photodiode.
Claim 2
Dependent Claim
78 words
A solid state image pickup device, comprising: a photodiode for receiving incident light and for performing photoelectric conversion of said incident light; a first transistor coupled to said photodiode for converting a voltage produced across said photodiode into an electric current; and a charge storage capacitor for storing an electric charge in response to said electric current, wherein said electric charge is stored in said charge storage capacitor with exclusive application of forwardly biased voltage to said photodiode.
Claim 3
Dependent Claim
30 words
A solid state image pickup device as claimed in claim 1, further comprising a second transistor coupled to said first transistor, said second transistor being responsive to a reset signal.
Claim 4
Dependent Claim
35 words
A solid state image pickup device as claimed in claim 2, wherein said charge storage capacitor comprises a junction capacitance formed with the drain of said first transistor and the source of said second transistor.
Claim 5
Dependent Claim
22 words
A solid state image pickup device as claimed in claim 1, wherein said stored electric current is read by a read-out circuit.
Claim 6
Dependent Claim
20 words
A solid state image pickup device as claimed in claim 4, wherein said read-out circuit is a MOS sensor-type device.
Claim 7
Dependent Claim
23 words
A solid state image pickup device as claimed in claim 4, wherein said read-out circuit is an interline charge coupled device type device.
Claim 8
Dependent Claim
22 words
A solid state image pickup device as claimed in claim 4, wherein said read-out circuit is a horizontal read-out transfer type device.
Claim 9
Dependent Claim
20 words
A solid state image pickup device as claimed in claim 4, wherein said read-out circuit is an amplification type device.
Claim 10
Dependent Claim
48 words
A solid state image pickup device, comprising: means for converting irradiated light to a voltage level; means for converting said voltage level to a current signal; means for extracting an output signal corresponding to time quadrature of said current signal; and means for reading out said output signal.
Claim 11
Dependent Claim
48 words
A solid state image pickup device, comprising: means for converting irradiated light to a voltage level; means for converting said voltage level to a current signal; means for extracting an output signal corresponding to time quadrature of said current signal; and means for reading out said output signal.
Claim 12
Dependent Claim
25 words
A solid state image pickup device as claimed in claim 9, wherein said means for converting irradiated light to a voltage level is a photodiode.
Claim 13
Dependent Claim
26 words
A solid state image pickup device as claimed in claim 9, wherein said means for converting said voltage level to a current signal is a transistor.
Claim 14
Dependent Claim
30 words
A solid state image pickup device as claimed in claim 10 wherein said means for converting said voltage level to a current signal is a transistor coupled to said photodiode.
Claim 15
Dependent Claim
32 words
A solid state image pickup device as claimed in claim 9, wherein said means for providing an output signal corresponding to time quadrature of said current signal is a charge storage capacitor.
Claim 16
Dependent Claim
78 words
A solid state image pickup device, comprising: a source of a reset signal; a diode, responsive to light, having first and second terminals; a first transistor having a source, drain, and gate, said first terminal of said diode being connected to said gate; and a capacitance formed across said source and drain, said capacitance being connected to a readout terminal, and electric charge of said capacitance being stored with exclusive application of forwardly biased voltage to said diode.
Claim 17
Dependent Claim
78 words
A solid state image pickup device, comprising: a source of a reset signal; a diode, responsive to light, having first and second terminals; a first transistor having a source, drain, and gate, said first terminal of said diode being connected to said gate; and a capacitance formed across said source and drain, said capacitance being connected to a readout terminal, and electric charge of said capacitance being stored with exclusive application of forwardly biased voltage to said diode.
Claim 18
Dependent Claim
89 words
A solid state image pickup device as claimed in claim 14, further comprising: a second transistor having a source, drain, and gate, said gate being connected to said source of a reset signal, and one of said source or drain being connected to one of the drain or source, respectively, of said first transistor, wherein said capacitance comprises the junction capacitance formed at the junction of the source of one of said first and said second transistors, and the drain of the other of said first and second transistors.
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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) | 1993-07-30 | 1994-01-29 | 1994-07-31 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-07-30 | 1998-01-29 | 1998-07-31 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-07-30 | 2002-01-29 | 2002-07-31 | $7700.00 | Window Closed / Lapsed |