Back to results
US 11,236,993 B1Granted
Depth sensing using a time of flight system including a scanning beam in combination with a single photon avalanche diode array
AssigneeFacebook Technologies, LLC
InventorsMichael Hall, Xinqiao Liu
Life of this patent
Estimating the term…
Abstract
A depth camera assembly (DCA) includes a light generator emitting a beam of light into a local area and a detector. The detector captures light from the beam reflected by objects in the local area to a portion of an array of pixels that each include a single photon avalanche diode (SPAD). The location of the portion of the array is based in part on the angle of the beam emitted from the projector. The DCA identifies a set of pixels of the array corresponding to the portion and selectively retrieves current generated from the reflected light by the pixels in the portion of the array without retrieving current generated by pixels in other portions of the array.
Claims20
A depth camera assembly (DCA) comprising:
- a transmitter configured to illuminate a local area with outgoing light;
- a receiver configured to capture, in accordance with receiving instructions, one or more images of the local area including reflected light comprising portions of the outgoing light reflected from one or more objects in the local area, the receiver comprising:
- an array of single photon avalanche diode (SPAD) pixels, each SPAD pixel of the array configured to capture light from the local area including portions of the outgoing light reflected from one or more objects in the local are at each of one or more time instants,
- switches coupled to each SPAD pixel of the array,
- an aggregator coupled to the switches, the aggregator configured to sum current received from SPAD pixels coupled to the aggregator by activated switches for each time instant to generate an analog output signal and to convert, for each time instant, the analog output signal into a digital timestamp signal associated with a time instant, the aggregator comprising a comparator coupled to each switch coupled to a SPAD pixel of the array and configured to combine current generated by SPAD pixels coupled to activated switches and to generate a specific value in response to the combined current exceeding a threshold value and a time to digital converter (TDC) coupled to the comparator and configured to generate a digital representation of a time when the time to digital converter received the specific value from the comparator;
- and
- a controller coupled to the receiver, the controller configured to provide receiving instructions to the receiver including a control signal to switches coupled to a set of SPAD pixels of the array to activate the switches coupling the set of SPAD pixels to the aggregator.
4 more elements
A depth camera assembly (DCA) comprising:
- a transmitter configured to illuminate a local area with outgoing light;
- a receiver configured to capture, in accordance with receiving instructions, one or more images of the local area including reflected light comprising portions of the outgoing light reflected from one or more objects in the local area, the receiver comprising:
- an array of pixels comprising a plurality of columns of pixels and a plurality of rows of pixels, each pixel including a single photon avalanche diode (SPAD) coupled to a comparator configured to generate a particular value in response to current generated by the SPAD included in the pixel from light incident on the SPAD exceeding a threshold value;
- a set of output channels corresponding to each column of pixels, each comparator of a pixel of a column coupled to one output channel of the set of output channels via a switch;
- a plurality of sampling modules, each sampling module corresponding to a column of pixels, a sampling module corresponding to the column coupled to the set of output channels corresponding to the column and configured to determine a sum of the particular value received from pixels in the column coupled to an output channel of the set of output channels by an activated switch;
- and
- an addition module coupled to each of the plurality of sampling modules, the addition module configured to generate a temporal histogram by combining sums of the particular value received from each of the plurality of sampling modules;
- and
- a controller coupled to the receiver, the controller configured to provide receiving instructions to the receiver including a control signal to activate switches coupling each pixel in a set of pixels to a corresponding output channel of the set of output channels.
6 more elements
A detector comprising:
- an array of pixels comprising a plurality of columns of pixels and a plurality of rows of pixels, each pixel including as single photon avalanche diode (SPAD) coupled to a comparator configured to generate a particular value in response to current generated by the SPAD included in the pixel from light incident on the SPAD exceeding a threshold value;
- a set of output channels corresponding to each column of pixels, each comparator of a pixel of a column coupled to one output channel of the set of output channels via a switch;
- a plurality of sampling modules, each sampling module corresponding to a column of pixels, a sampling module corresponding to the column coupled to the set of output channels corresponding to the column and configured to determine a sum of the particular value received from pixels in the column coupled to an output channel of the set of output channels by an activated switch;
- and
- an addition module coupled to each of the plurality of sampling modules, the addition module configured to generate a temporal histogram by combining sums of the particular value received from each of the plurality of sampling modules.
2 more elements
Dependencies are inferred from the claim text.