Abstract: A method for optical sensing includes directing a series of optical pulses toward a target scene and imaging optical radiation that is reflected from the target scene onto an array of single-photon detectors, which output electrical pulses in response to photons that are incident thereon. The electrical pulses output by the single photon detectors are counted in multiple different gating intervals that are synchronized with each of the optical pulses, including at least first and second gating intervals at different, respective delays relative to the optical pulses, while the delays are swept over a sequence of different delay times during the series of the optical pulses. A time of flight of the optical pulses is computed by comparing respective first and second counts of the electrical pulses that were accumulated in the first and second gating intervals over the series of the optical pulses.

Abstract: Optical sensing apparatus includes at least one semiconductor substrate and a first array of single-photon detectors, which are disposed on the at least one semiconductor substrate, and second array of counters, which are disposed on the at least one semiconductor substrate and are configured to count electrical pulses output by the single-photon detectors. Routing and aggregation logic is configured, in response to a control signal, to connect the single-photon detectors to the counters in a first mode in which each of at least some of the counters aggregates and counts the electrical pulses output by a respective first group of one or more of the single-photon detectors, and in a second mode in which each of the at least some of the counters aggregates and counts the electrical pulses output by a respective second group of two or more of the single-photon detectors.

Abstract: Optical sensing apparatus includes at least one semiconductor substrate and a first array of single-photon detectors, which are disposed on the at least one semiconductor substrate, and second array of counters, which are disposed on the at least one semiconductor substrate and are configured to count electrical pulses output by the single-photon detectors. Routing and aggregation logic is configured, in response to a control signal, to connect the single-photon detectors to the counters in a first mode in which each of at least some of the counters aggregates and counts the electrical pulses output by a respective first group of one or more of the single-photon detectors, and in a second mode in which each of the at least some of the counters aggregates and counts the electrical pulses output by a respective second group of two or more of the single-photon detectors.

Abstract: A multimode interline charge coupled device having an array of light sensitive pixels, each configured to accumulate photocharge responsive to light incident on the pixel, and a controller configured to allocate a first portion of the pixels to accumulate photocharge responsive to light from a scene during a plurality of exposure periods and allocate a second portion of the pixels to store photocharge accumulated by pixels in the first portion to provide a plurality of images of the scene greater than two.

Abstract: Reduction in interference between different time of flight (ToF) cameras used for depth measurements and operating in the same application environment is achieved using a spread spectrum technique in which the cyclical operations of a pulsed light source such as a laser or light emitting diode (LED) and gated image sensor are varied in a pseudo-random manner in each camera. In an alternative embodiment, spread spectrum logic is applied in a ToF camera that employs phase modulation techniques.

Abstract: A wearable computer interface comprising a three dimensional (3D) range camera and a picture camera that image the user and a controller that process the images to identify the user and determine if the user is authorized to use the interface to access functionalities provided by a computer interfaced by the interface.

Abstract: A depth-sensing method for a time-of-flight depth camera includes irradiating a subject with pulsed light of spatially alternating bright and dark features, and receiving the pulsed light reflected back from the subject onto an array of pixels. At each pixel of the array, a signal is presented that depends on distance from the depth camera to the subject locus imaged onto that pixel. In this method, the subject is mapped based on the signal from pixels that image subject loci directly irradiated by the bright features, while omitting or weighting negatively the signal from pixels that image subject loci under the dark features.

Abstract: A multimode interline charge coupled device having an array of light sensitive pixels, each configured to accumulate photocharge responsive to light incident on the pixel, and a controller configured to allocate a first portion of the pixels to accumulate photocharge responsive to light from a scene during a plurality of exposure periods and allocate a second portion of the pixels to store photocharge accumulated by pixels in the first portion to provide a plurality of images of the scene greater than two.

Abstract: An embodiment of the invention provides a spectral imager for imaging a scene comprising a semiconductor photosensor comprising light sensitive pixels and a power source that applies voltage to the photosensor to control responsivity of the pixels to light incident on the pixels in different wavelengths bands of light.

Abstract: Reduction in interference between different time of flight (ToF) cameras used for depth measurements and operating in the same application environment is achieved using a spread spectrum technique in which the cyclical operations of a pulsed light source such as a laser or light emitting diode (LED) and gated image sensor are varied in a pseudo-random manner in each camera. In an alternative embodiment, spread spectrum logic is applied in a ToF camera that employs phase modulation techniques.

Abstract: An imaging system includes first and second imaging arrays separated by a fixed distance, first and second drivers, and a modulated light source. The first imaging array includes a plurality of phase-responsive pixels distributed among a plurality of intensity-responsive pixels; the modulated light source is configured to emit modulated light in a field of view of the first imaging array. The first driver is configured to modulate the light output from the modulated light source and synchronously control charge collection from the phase-responsive pixels. The second driver is configured to recognize positional disparity between the intensity-responsive pixels of the first imaging array and corresponding intensity-responsive pixels of the second imaging array.

Abstract: Embodiments are disclosed that relate to controlling a depth camera. In one example, a method comprises emitting light from an illumination source toward a scene through an optical window, selectively routing a at least a portion of the light emitted from the illumination source to an image sensor such that the portion of the light is not transmitted through the optical window, receiving an output signal generated by the image sensor based on light reflected by the scene, the output signal including at least one depth value of the scene, and adjusting the output signal based on the selectively routed portion of the light.

Abstract: A wearable computer interface comprising a three dimensional (3D) range camera and a picture camera that image the user and a controller that process the images to identify the user and determine if the user is authorized to use the interface to access functionalities provided by a computer interfaced by the interface.

Abstract: An embodiment of the invention provides a spectral imager for imaging a scene comprising a semiconductor photosensor comprising light sensitive pixels and a power source that applies voltage to the photosensor to control responsivity of the pixels to light incident on the pixels in different wavelengths bands of light.

Abstract: A system for optical coherence tomography (OCT) is disclosed. The system comprises an optical interferometer apparatus configured to split an optical beam into a reference beam directed to a reference reflector and a sample beam directed to a sample, and to combine a reflected beam from the reference reflector with a returning beam from the sample to form a combined optical signal. The system further comprises a two photon detector configured to detect the combined optical signal by two photon absorption and to provide a corresponding electrical signal, a frequency separation system configured to separate a low frequency component from the electrical signal, and a data processor configured for providing a topographic reconstruction of the sample based, at least in part, on the low frequency component.

Abstract: A depth-sensing method for a time-of-flight depth camera includes irradiating a subject with pulsed light of spatially alternating bright and dark features, and receiving the pulsed light reflected back from the subject onto an array of pixels. At each pixel of the array, a signal is presented that depends on distance from the depth camera to the subject locus imaged onto that pixel. In this method, the subject is mapped based on the signal from pixels that image subject loci directly irradiated by the bright features, while omitting or weighting negatively the signal from pixels that image subject loci under the dark features.

Abstract: A system for measuring one or more characteristics of light of a photon energy Eph from a light source, that can be determined from measuring three-photon absorption events, the system comprising: a) a detector having a band gap material characterized by gap energy between 2.1 and 3 times Eph; b) an optical element configured to concentrate a beam of light from the light source on the detector; c) a signal amplifier that amplifies an output signal indicative of when three photons produced by the light source undergo a three-photon absorption event in the band gap material; and d) an analyzer that analyzes the output signal to count or measure a rate of the three-photon absorption events, and determines the one or more characteristics of the light from the light source.

Abstract: There is provided a new architecture for all-optical logic architecture. In this architecture the gate is partitioned into a linear front-end followed by a nonlinear back-end. The logic calculation is practically performed within the linear stage, easing the requirements placed on the non-linear part and thus reducing the gate complexity. The new structures provide flexibility and improved performance for the all-optical logic. The proposed scheme may be integrated optics/electronics. An important additional attribute of our all-optical logic family is reconfigurability, i.e. the ability of the hardware architecture or devices to rapidly alter the functionalities of its components and the interconnection between them as needed.

Abstract: A semiconductor, room-temperature, electrically excited, two-photon device with thick optically active layer is provided. The intrinsic AlGaAs active layer is sandwiched between two intrinsic graded waveguide layers having increased aluminum concentration at increased distance from the active layer. The waveguide structure is sandwiched between two cladding layers of high aluminum concentration, n and p doped respectively. The structure is epitaxially grown on a substrate and further comprises other layers such as buffer, graded layers and contact layers. An etched ridge provides lateral confinement for light. The device provides two-photons gain and may be used in light sources, optical amplifiers, pulse compressors and lasers.

Abstract: A system for measuring one or more characteristics of light of a photon energy Eph from a light source, that can be determined from measuring three-photon absorption events, the system comprising: a) a detector having a band gap material characterized by gap energy between 2.1 and 3 times Eph; b) an optical element configured to concentrate a beam of light from the light source on the detector; c) a signal amplifier that amplifies an output signal indicative of when three photons produced by the light source undergo a three-photon absorption event in the band gap material; and d) an analyzer that analyzes the output signal to count or measure a rate of the three-photon absorption events, and determines the one or more characteristics of the light from the light source.