Photoelectric conversion apparatus
AssigneeCanon Kabushiki Kaisha
InventorsKazuo Yamazaki, Hidekazu Takahashi
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Abstract
A photoelectric conversion apparatus includes a photoelectric conversion element and a logarithmic conversion unit for converting a signal from the photoelectric conversion element to a logarithmically compressed voltage by means of a diode characteristic of p-n junction. The p-n junction in the logarithmic conversion unit is composed of any two terminals of the emitter, the base and the collector of the bipolar transistor, and a residual terminal of the transistor is connected to a semiconductor substrate.
Claims11
A photoelectric conversion apparatus, comprising:
- a photoelectric conversion element;
- and
- a logarithmic conversion unit which converts a signal from said photoelectric conversion element to a logarithmically compressed voltage by means of a diode characteristic of a p-n junction;
- wherein the p-n junction in said logarithmic conversion unit is composed of any two terminals of an emitter, a base and a collector of a bipolar transistor, and a residual terminal of the bipolar transistor is connected to a semiconductor substrate.
A photoelectric conversion apparatus, comprising:
- a photoelectric conversion element;
- and
- a logarithmic conversion unit which converts a current from said photoelectric conversion element to a logarithmically compressed voltage,
- wherein said logarithmic conversion unit performs logarithmic conversion by means of a diode characteristic of a diode formed by junction of a first semiconductor region of a first conductivity type with a second semiconductor region of a conductivity type opposite to the first conductivity type, said second semiconductor region is formed by being joined to a semiconductor substrate of the first conductivity type on which said logarithmic conversion unit is formed, and said photoelectric conversion element and said logarithmic compression unit are formed on the same semiconductor substrate in accordance with a CMOS process.
A photoelectric conversion apparatus, comprising:
- a photoelectric conversion element;
- a logarithmic conversion unit which converts a signal from said photoelectric conversion element to a logarithmically compressed voltage;
- an inversion element which inverts a polarity of an output from said logarithmic conversion unit;
- and
- a correction element which corrects a diode characteristic of a p-n junction in said photoelectric conversion element.
Dependencies are inferred from the claim text.