Time-of-flight image sensor with distance determination
AssigneeSony Semiconductor Solutions Corporation
InventorPing Wah Wong
Life of this patent
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Abstract
A time-of-flight camera includes a light generator that generates an emitted light wave, a light sensor that receives a reflected light wave that corresponds to the emitted light wave reflected from an object, and distance determination circuitry. The distance determination circuitry determines response signals based on the reflected light wave, calculates signs corresponding to differences between pairs of the response signals, determines a phase region based on the signs, and determines a distance between the time-of-flight camera and the object based on a ratio of the differences.
Claims20
A time-of-flight camera, comprising:
- a light generator configured to generate an emitted light wave;
- a light sensor configured to receive a reflected light wave, the reflected light wave corresponding to the emitted light wave reflected from an object;
- and
- distance determination circuitry configured to:
- determine a plurality of response signals based on the reflected light wave, respective ones of the plurality of response signals corresponding to a different timing window of a period of the reflected light wave,
- calculate a first sign corresponding to a first difference between a first pair of the plurality of response signals and a second sign corresponding to a second difference between a second pair of the plurality of response signals, the first sign indicating whether the first difference is positive or negative and the second sign indicating whether the second difference is positive or negative,
- determine a phase region based on the first sign and the second sign, and
- determine a distance between the time-of-flight camera and the object based on a distance formula corresponding to the determined phase region, wherein the distance formula includes a ratio including the first difference and the second difference.
A distance determination method in a time-of-flight camera, comprising:
- generating an emitted light wave;
- receiving a reflected light wave, the reflected light wave corresponding to the emitted light wave reflected from an object;
- determining a plurality of response signals based on the reflected light wave, respective ones of the plurality of response signals corresponding to a different timing window of a period of the reflected light wave;
- calculating a first sign corresponding to a first difference between a first pair of the plurality of response signals and a second sign corresponding to a second difference between a second pair of the plurality of response signals, the first sign indicating whether the first difference is positive or negative and the second sign indicating whether the second difference is positive or negative,
- determining a phase region based on the first sign and the second sign;
- and
- determining a distance between the time-of-flight camera and the object based on a distance formula corresponding to the determined phase region, wherein the distance formula includes a ratio including the first difference and the second difference.
Dependencies are inferred from the claim text.