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US 11,378,665 B2Granted
Distance measuring apparatus and method of operating the same
AssigneeKorea Research Institute of Standards and Science
InventorsJae-Wan Kim, Jae-Yong Lee, Jong-Ahn Kim, Jae-Heun Woo, Young Pyo Hong
Life of this patent
Estimating the term…
Abstract
A distance measuring apparatus includes an image sensor and an image sensor driver. The image sensor includes a photodiode, a first capacitor and a second capacitor, and a first transfer gate and a second transfer gate configured to transmit an output of the photodiode to the respective first and second capacitors. The image sensor driver is configured to complementarily drive the first transfer gate and the second transfer gate.
Claims18
A distance measuring apparatus comprising:
- an image sensor including a photodiode, a first capacitor and a second capacitor, and a first transfer gate and a second transfer gate configured to deliver an output of the photodiode to the respective first and second capacitors;
- and
- an image sensor driver configured to complementarily drive the first transfer gate and the second transfer gate, provide a first gate voltage sweeping from a low level to a high level to the first transfer gate, and provide a second gate voltage sweeping from the high level to the low level to the second transfer gate;
- and
- a light source that outputs a pulse light, wherein:
- the image sensor driver drives the first gate voltage and the second gate voltage in synchronization with the pulse light during a predetermined duty time,
- the pulse light has a width that is smaller than the predetermined duty time, and
- a time of flight (TOF) between a time at which the light pulse is irradiated and a time at which a reflected light pulse is incident is larger than the width of the pulse light.
5 more elements
A method of operating a distance measuring apparatus, comprising:
- charging first and second capacitors connected to a photodiode through first and second transfer gates, respectively;
- irradiating a pulse light from a light source to a target object, wherein the pulse light has a width smaller than a predetermined duty time;
- using an image sensor driver, driving a first gate voltage and a second gate voltage in synchronization with irradiating the light during the predetermined duty time, wherein the first gate voltage sweeps from a low level to a high level, and the second gate voltage sweeps from the high level to the low level;
- decreasing a voltage of the first capacitor in proportion to (i) an intensity of light reflected from the target object and incident on the photodiode and (ii) a time elapsed after the light is irradiated;
- decreasing a voltage of the second capacitor in proportion to the intensity of the light incident on the photodiode and in inverse proportion to the time elapsed after the light is irradiated;
- and
- measuring a distance between the target object and the distance measuring apparatus using the voltage of the first capacitor and the voltage of the second capacitor,
- wherein a time of flight (TOF) between a time at which the light pulse is irradiated and a time at which the light reflected from the target object is incident on the photodiode is larger than the width of the pulse light.
5 more elements
Dependencies are inferred from the claim text.