Optical sensor and output circuit thereof
AssigneeRohm Co., Ltd.
InventorTetsuya Kitade
Life of this patent
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Abstract
An optical sensor is provided according to an embodiment of the present disclosure. The optical sensor includes a first photodiode, a second photodiode having characteristics different from characteristics of the first photodiode, filters configured to block or transmit a specific wavelength range of the light, and an output circuit configured to correct a sensitivity deviation, which may be caused when one of the filters is used for the first photodiode, based on a sensitivity deviation, which may be caused when the other filter of the same kind as the one filter is used for the second photodiode, and output only the specific wavelength range of the light.
Claims9
An optical sensor comprising:
- a fifth photodiode including a first transmission filter formed on a light receiving surface of the fifth photodiode;
- a sixth photodiode including a second transmission filter formed on a light receiving surface of the sixth photodiode;
- and
- an output circuit configured to subtract an output of the sixth photodiode from an output of the fifth photodiode,
- wherein the first and second transmission filters are configured to transmit a specific wavelength range of the light and the sixth photodiode has characteristics different from characteristics of the fifth photodiode.
An output circuit comprising:
- an arithmetic circuit which is connected to a fifth photodiode including a first transmission filter formed on a light receiving surface the fifth photodiode, and a sixth photodiode including a second transmission filter formed on a light receiving surface of the sixth photodiode, and configured to subtract an output of the sixth photodiode from the output of the fifth photodiode;
- a conversion circuit configured to convert an analog signal from the arithmetic circuit into a digital signal;
- and
- a logic circuit configured to subject the digital signal from the conversion circuit to a predetermined calculation process,
- wherein the first and second transmission filters are configured to transmit a specific wavelength range of the light and the sixth photodiode has characteristics different from characteristics of the fifth photodiode.
Dependencies are inferred from the claim text.