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US4712136A Expired / Lapsed US ⏱️ 0.0 years remaining

Signal processing circuit of solid state image pickup device

Assignee: Canon Inc
•
Filing: 1986-09-10
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Granted: 1987-12-08
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Expires: 2006-09-10
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Abstract

Abstract There is a solid state image pickup device having a signal voltage output circuit to output a charge signal as voltage information through a charge-voltage converter and a correction voltage output circuit to generate a reference voltage into which no signal charge is input and which has a circuit arrangement similar to the signal voltage output circuit. The invention intends to provide a signal processing circuit of such a solid state image pickup device in which the output of the correction voltage output circuit is provided with a time constant circuit, and this signal processing circuit consists of a differential amplifier to amplify the difference between the correction voltage output derived through the time constant circuit and the output of the signal voltage output circuit.

Inventors

  • 👤 Tokuichi Tsunekawa
  • 👤 Yuichi Sato

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-27 03:08
CPC Classifications
G; G11; G11C; G11C27/00; G11C27/04; H; H04; H04N; H04N25/00; H04N25/60; H04N25/618

Claims Analysis

Total Claims: 17
Claim 1
Independent Claim 109 words
A signal processing circuit of a solid state image pickup device having a signal voltage output circuit for outputting a charge signal as voltage information through a charge voltage converter and a correction voltage output circuit for generating a reference voltage into which no signal charge is input and which has a circuit arrangement similar to said signal voltage output circuit, wherein an output of said correction voltage output circuit is provided with a time constant circuit, and said signal processing circuit has a circuit for differentially amplifying a correction voltage output which is derived through said time constant circuit and an output of said signal voltage output circuit.
Claim 2
Dependent Claim 109 words
A signal processing circuit of a solid state image pickup device having a signal voltage output circuit for outputting a charge signal as voltage information through a charge voltage converter and a correction voltage output circuit for generating a reference voltage into which no signal charge is input and which has a circuit arrangement similar to said signal voltage output circuit, wherein an output of said correction voltage output circuit is provided with a time constant circuit, and said signal processing circuit has a circuit for differentially amplifying a correction voltage output which is derived through said time constant circuit and an output of said signal voltage output circuit.
Claim 3
Dependent Claim 20 words
A signal processing circuit according to claim 1, wherein said time constant circuit consists of a resistor and a capacitor.
Claim 4
Dependent Claim 32 words
A signal processing circuit according to claim 1, wherein a time constant of said time constant circuit is sufficiently longer than a period of a read clock pulse of the signal output.
Claim 5
Dependent Claim 119 words
A signal processing apparatus comprising: (a) photoelectric converting means for converting light information into an electric signal, said converting means being arranged on a semiconductor substrate; (b) first output means whose input is connected to said photoelectric converting means and which outputs the electric signal of the photoelectric converting means; (c) second output means which is arranged on said semiconductor substrate and which has substantially the same input/output characteristics as those of said first output means; (d) a high-band cut filter for cutting out the high frequency components in an output of said second output means; and (e) arithmetic operating means for arithmetically operating an output of said first output means and an output of said high-band cut filter.
Claim 6
Dependent Claim 119 words
A signal processing apparatus comprising: (a) photoelectric converting means for converting light information into an electric signal, said converting means being arranged on a semiconductor substrate; (b) first output means whose input is connected to said photoelectric converting means and which outputs the electric signal of the photoelectric converting means; (c) second output means which is arranged on said semiconductor substrate and which has substantially the same input/output characteristics as those of said first output means; (d) a high-band cut filter for cutting out the high frequency components in an output of said second output means; and (e) arithmetic operating means for arithmetically operating an output of said first output means and an output of said high-band cut filter.
Claim 7
Dependent Claim 27 words
A signal processing apparatus according to claim 4, wherein said photoelectric converting means includes an image sensor for converting an optical image into a serial electric signal.
Claim 8
Dependent Claim 21 words
A signal processing apparatus according to claim 5, wherein said image sensor includes a line sensor for detecting a line image.
Claim 9
Dependent Claim 16 words
A signal processing apparatus according to claim 4, wherein said first output means includes an amplifier.
Claim 10
Dependent Claim 21 words
A signal processing apparatus according to claim 7, wherein said first output means converts a charge signal into a voltage signal.
Claim 11
Dependent Claim 37 words
A signal processing apparatus according to claim 4, wherein said second output means has substantially the same constitution as that of the first output means excluding that an input is not connected to said photoelectric converting means.
Claim 12
Dependent Claim 18 words
A signal processing apparatus according to claim 4, wherein said high-band cut filter includes a low pass filter.
Claim 13
Dependent Claim 18 words
A signal processing apparatus according to claim 10, wherein said low pass filter includes a time constant circuit.
Claim 14
Dependent Claim 26 words
A signal processing apparatus according to claim 11, further having a signal source for supplying periodic read clock pulses to said first and second output means.
Claim 15
Dependent Claim 29 words
A signal processing apparatus according to claim 12, wherein said time constant circuit has a time constant which is sufficiently longer than a period of said read clock pulse.
Claim 16
Dependent Claim 36 words
A signal processing apparatus according to claim 4, wherein said arithmetic operating means includes subtracting means for performing a subtraction between an output of said first output means and an output of said high-band cut filter.
Claim 17
Dependent Claim 16 words
A signal processing apparatus according to claim 14, wherein said subtracting means includes a differential amplifier.

References Cited (Backward Citations)

US4500924A Cited
US4511804A Cited
US4635126A Cited
US4600843A Cited
US4623927A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1990-12-07 1991-06-08 1991-12-08 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1994-12-07 1995-06-08 1995-12-08 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1998-12-07 1999-06-08 1999-12-08 $7700.00 Window Closed / Lapsed

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