US 11,888,013 B2 · High-sensitivity depth sensor with non-avalanche photodetector

Abstract

A sensing device includes a light source to emit light, a light sensor to detect reflection of the emitted light and distance determination circuitry responsive to reflected-light detection within the light sensor. The light sensor includes a photodetector having a photocharge storage capacity in excess of one electron and an output circuit that generates an output signal responsive to light detection within the photodetector with sub-hundred nanosecond latency. The distance determination circuitry measures an elapsed time based on transition of the output signal in response to photonic detection within the photodetector and determines, based on the elapsed time, a distance between the sensing device and a surface that yielded the reflection of the emitted light.

Claims20

Dependent claims

A sensing device, comprising:

a light sensor to detect light reflected from a surface, the light sensor comprising:
a photodiode including a photowell capable of storing two or more electrons generated in response to detection of the light;
and
readout circuitry to generate an output signal that transitions between voltage levels in response to storage of each of the electrons within the photodiode;
and
measurement circuitry to generate a value representative of a distance between the sensing device and the surface based on the output signal, the measurement circuitry comprising:
a counter that outputs an incremental sequence of count values;
and
a plurality of latching circuits that receive respective input signals generated based on the output signal from the readout circuitry and store respective count values of the incremental sequence from the counter when the respective input signals exceed respective threshold levels.

6 more elements

A method of operation within a sensing device, the method comprising:

storing, using a photodiode, two or more electrons within a photowell of the photodiode in response to light reflected from a surface;
generating, using readout circuitry, an output signal that transitions between voltage levels in response to storage of each of the electrons within the photodiode;
generating, using a counter, an incremental sequence of count values;
storing, a plurality of latching circuits receiving respective input signals that are generated based on the output signal, respective count values of the incremental sequence when the respective input signals exceed respective threshold levels;
and
generating, using a measurement circuitry, a value representative of a distance between the sensing device and the surface based on the stored count values of the latching circuits.

3 more elements

Dependencies are inferred from the claim text.

High-sensitivity depth sensor with non-avalanche photodetector

Life of this patent

High-sensitivity depth sensor with non-avalanche photodetector

Life of this patent

Abstract

Claims20