Abstract: Structures and methods for three-dimensional image sensing using high frequency modulation includes CMOS-implementable sensor structures using differential charge transfer, including such sensors enabling rapid horizontal and slower vertical dimension local charge collection. Wavelength response of such sensors can be altered dynamically by varying gate potentials. Methods for producing such sensor structures on conventional CMOS fabrication facilities include use of “rich” instructions to command the fabrication process to optimize image sensor rather than digital or analog ICs. One detector structure has closely spaced-apart, elongated finger-like structures that rapidly collect charge in the spaced-apart direction and then move collected charge less rapidly in the elongated direction. Detector response is substantially independent of the collection rate in the elongated direction.

Abstract: A technique is provided for removing blurring from an image captured by an imaging device. The imaging device may include a lens and an imaging medium comprised of a plurality of imaging pieces. According to an embodiment, a distance is determined between individual imaging pieces of the imaging medium and a region on the target object that corresponds to the respective individual imaging piece. The image of the target object is captured on the imaging medium. Blurring is removed from the captured image using the distances identified for the individual imaging pieces.

Abstract: A system used with a virtual device inputs or transfers information to a companion device, and includes two optical systems OS1, OS2. In a structured-light embodiment, OS1 emits a fan beam plane of optical energy parallel to and above the virtual device. When a user-object penetrates the beam plane of interest, OS2 registers the event. Triangulation methods can locate the virtual contact, and transfer user-intended information to the companion system. In a non-structured active light embodiment, OS1 is preferably a digital camera whose field of view defines the plane of interest, which is illuminated by an active source of optical energy. Preferably the active source, OS1, and OS2 operate synchronously to reduce effects of ambient light. A non-structured passive light embodiment is similar except the source of optical energy is ambient light. A subtraction technique preferably enhances the signal/noise ratio. The companion device may in fact house the present invention.

Abstract: A user with hand or stylus inputs information to a companion system such as a PDA, a cell telephone, an appliance, or other device using a virtual input device such as an image of a keyboard. A sensor captures data representing a single image at a given time, from which data three-dimensional positional information as to if, when in time, and where on the virtual input device user-interaction or contact occurred. The processed digital information is output to the companion system. In a virtual keyboard application, the companion system can display an image of a keyboard, including an image of a keyboard showing user fingers, and/or alphanumeric text as such data is input by the user on the virtual input device.

Abstract: In a three-dimensional data acquisition system, coordinate transformation and geometric error correction are avoided by representing data in a sensor array coordinate system (i,j,k) rather than a conventional (x,y,z) coordinate system. A preferably point-sized sub-region is defined for each potential region of interest for a virtual input device subject to interaction with a user-controlled object. The (i,j,k) coordinate system used relates to raw data, and correction for several types of geometric error and optical lens error are avoided by determining interaction with such raw coordinate data. As a result, substantial processing overhead may be avoided.

Abstract: A plurality of sound-detecting devices are configured to detect sound from an event of interest. Information about the sound is recorded that is dependent on a distance between the source position and the location of the sound-detection devices. The source position is approximated using the recorded information and the relative position of individual sound-detection devices to one another. The approximated source position is used as input for operating a electronic device.

Abstract: High dynamic range brightness information is acquired by inputting detection current to a high (adjustable) gain resettable integrator whose output V(t) is compared to a Vth threshold by a comparator whose output is counted by a reset counter as V(t)≧Vth. When a desired count is attained, data acquisition ends, the counter is read, and the entire circuit is reset. A TOF data acquisition circuit includes first and second sequences of series-coupled delay units, and a like number of latch units coupled between respective delay units. A phase discriminator compares output from each chain and feedback a signal to one of the chains and to a comparator and can equalize delay through each chain. A control voltage is coupled to the remaining chain to affect through-propagation delay time. The latch units can capture the precise time when V(t)≧Vth. Successive measurement approximation can enhance TOF resolution.

Abstract: A three-dimension distance time-of-flight system is disclosed in which distance values are acquired by a plurality of sensors independently from each other. For use with this and similar systems, Z-distance accuracy and resolution are enhanced using various techniques including over-sampling acquired sensor data and forming running averages, or forming moving averages. Acquired data may be rejected if it fails to meet criteria associated with distance, luminosity, velocity, or estimated shape information reported by neighboring sensors. A sub-target having at least one pre-calibrated reflectance zone is used to improve system measurement accuracy. Elliptical error is corrected for using a disclosed method, and reversible mapping of Z-values into RGB is provided.

Abstract: A user inputs digital data to a companion system such as a PDA, a cell telephone, an applicance, device using a virtual input device such as an image of a keyboard. A sensor captures three-dimensional positional information as to location of the user's fingers in relation to where keys would be on an actual keyboard. This information is processed with respect to finger locations and velocities and shape to determine when virtual keys would have been struck. The processed digital information is output to the companion system. The companion system can display an image of a keyboard, including an image of a keyboard showing user fingers, and/or alphanumeric text as such data is input by the user on the virtual input device.

Abstract: A three-dimensional time-of-flight (TOF) system includes a low power optical emitter whose idealized output S1=cos(&ohgr;·t) is reflected by a target distance z away as S2=A·cos(&ohgr;·t+&PHgr;), for detection by a two-dimensional array of pixel detectors and associated narrow bandwidth detector electronics and processing circuitry preferably fabricated on a common CMOS IC. Phase shift &PHgr; is proportional to TOF or z, z=&PHgr;·C/2·&ohgr;=&PHgr;·C/{2·(2·&pgr;·f)}, and A is brightness. &PHgr;, z, and A are determined by homodyne-mixing S2 with an internally generated phase-delayed version of S1, whose phase is dynamically forced to match the phase of S2 by closed-loop feedback. Idealized mixer output per each pixel detector is 0.5·A·{cos(2&ohgr;·t+&PHgr;)+cos(&PHgr;)}.

Abstract: A preferably CMOS-implementable system measures distance and/or brightness by illuminating a target with emitted optical energy having a modulated periodic waveform whose high frequency component may be idealized as S1=cos(&ohgr;·t). A fraction of the emitted optical energy is reflected by a target and detected with at least one in a plurality of semiconductor photodetectors. Photodetector quantum efficiency is modulated to process detected signals to yield data proportional to the distance z separating the target and photodetector. Detection includes measuring phase change between the emitted optical energy and the reflected fraction thereof. Quantum efficiency can be modulated with fixed or variable phase methods and may be enhanced using enhanced photocharge collection, differential modulation, and spatial and temporal multiplexing. System power requirements may be reduced with inductors that resonate with photodetector capacitance at the operating frequency.

Abstract: A preferably CMOS-implementable system measures distance and/or brightness by illuminating a target with emitted optical energy having a modulated periodic waveform whose high frequency component may be idealized as S1=cos(&ohgr;·t). A fraction of the emitted optical energy is reflected by a target and detected with at least one in a plurality of semiconductor photodetectors. Photodetector quantum efficiency is modulated to process detected signals to yield data proportional to the distance z separating the target and photodetector. Detection includes measuring phase change between the emitted optical energy and the reflected fraction thereof. Quantum efficiency can be modulated with fixed or variable phase methods and may be enhanced using enhanced photocharge collection, differential modulation, and spatial and temporal multiplexing. System power requirements may be reduced with inductors that resonate with photodetector capacitance at the operating frequency.

Abstract: A three-dimension distance time-of-flight system is disclosed in which distance values are acquired by a plurality of sensors independently from each other. For use with this and similar systems, Z-distance accuracy and resolution are enhanced using various techniques including over-sampling acquired sensor data and forming running averages, or forming moving averages. Acquired data may be rejected if it fails to meet criteria associated with distance, luminosity, velocity, or estimated shape information reported by neighboring sensors. A sub-target having at least one pre-calibrated reflectance zone is used to improve system measurement accuracy. Elliptical error is corrected for using a disclosed method, and reversible mapping of Z-values into RGB is provided.

Abstract: A three-dimensional imaging system is fabricated on a single IC. The system includes a two-dimensional array of pixel light sensing detectors and dedicated electronics and associated processing circuitry, all preferably fabricated on a single IC using CMOS fabrication techniques. The system includes a detector array comprising a plurality of pixel photodiodes and photodiode circuits, wherein each pixel photodiode acquires delay time data and pulse brightness data simultaneously. The system emits an energy pulse at time t0 and a fraction of the energy is returned to the array by a target object. Photodiodes in the array output a brightness signal B(t) that is integrated. An elapsed time ET from t0 to when said B(t) attains a predetermined threshold value is determined, where the slope of B(t) is B/PW, where B is B(t) after integrating over a time equal to the emitted pulse width PW.

Abstract: A preferably CMOS-implementable method measures distance and/or brightness by illuminating a target with emitted optical energy having a modulated periodic waveform whose high frequency component may be idealized as S1=cos(&ohgr;·t). A fraction of the emitted optical energy is reflected by a target and detected with at least one in a plurality of semiconductor photodetectors. Photodetector quantum efficiency is modulated to process detected signals to yield data proportional to the distance z separating the target and photodetector. Detection includes measuring phase change between the emitted optical energy and the reflected fraction thereof. Quantum efficiency can be modulated with fixed or variable phase methods and may be enhanced using enhanced photocharge collection, differential modulation, and spatial and temporal multiplexing. System power requirements may be reduced with inductors that resonate with photodetector capacitance at the operating frequency.

Abstract: A three-dimension distance time-of-flight system is disclosed in which distance values are acquired by a plurality of sensors independently from each other. For use with this and similar systems, Z-distance accuracy and resolution are enhanced using various techniques including over-sampling acquired sensor data and forming running averages, or forming moving averages. Acquired data may be rejected if it fails to meet criteria associated with distance, luminosity, velocity, or estimated shape information reported by neighboring sensors. A sub-target having at least one pre-calibrated reflectance zone is used to improve system measurement accuracy. Elliptical error is corrected for using a disclosed method, and reversible mapping of Z-values into RGB is provided.

Abstract: High dynamic range brightness information is acquired by inputting detection current to a high (adjustable) gain resettable integrator whose output V(t) is compared to a Vth threshold by a comparator whose output is counted by a reset counter as V(t)≧Vth. When a desired count is attained, data acquisition ends, the counter is read, and the entire circuit is reset. A TOF data acquisition circuit includes first and second sequences of series-coupled delay units, and a like number of latch units coupled between respective delay units. A phase discriminator compares output from each chain and feedback a signal to one of the chains and to a comparator and can equalize delay through each chain. A control voltage is coupled to the remaining chain to affect through-propagation delay time. The latch units can capture the precise time when V(t)≧Vth. Successive measurement approximation can enhance TOF resolution.

Abstract: A virtual simulation system generates an image of a virtual control on a display that may be a heads-up-display in a vehicle. The system uses three-dimensional range finding data to determine when a user is sufficiently close to the virtual control to “manipulate” the virtual control. The user “manipulation” is sensed non-haptically by the system, which causes the displayed control image to move in response to user manipulation. System output is coupled, linearly or otherwise, to an actual device having a parameter that is adjusted substantially in real-time by user-manipulation of the virtual image. System generated displays can be dynamic and change appearance when a user's hand is in close proximity. displays can disappear until needed, or can include menus and icons to be selected by the user who points towards or touches the virtual images. System generate images can include representation of the user for use in a training or gaming system.

Abstract: A preferably CMOS-implementable method measures distance and/or brightness by illuminating a target with emitted optical energy having a modulated periodic waveform whose high frequency component may be idealized as S1=cos(&ohgr;·t). A fraction of the emitted optical energy is reflected by a target and detected with at least one in a plurality of semiconductor photodetectors. Photodetector quantum efficiency is modulated to process detected signals to yield data proportional to the distance z separating the target and photodetector. Detection includes measuring phase change between the emitted optical energy and the reflected fraction thereof. Quantum efficiency can be modulated with fixed or variable phase methods and may be enhanced using enhanced photocharge collection, differential modulation, and spatial and temporal multiplexing. System power requirements may be reduced with inductors that resonate with photodetector capacitance at the operating frequency.

Abstract: In a three-dimensional data acquisition system, coordinate transformation and geometric error correction are avoided by representing data in a sensor array coordinate system (i, j, k) rather than a conventional (x, y, z) coordinate system. A preferably point-sized sub-region is defined for each potential region of interest for a virtual input device subject to interaction with a user-controlled object. The (i, j, k) coordinate system used relates to raw data, and correction for several types of geometric error and optical lens error are avoided by determining interaction with such raw coordinate data. As a result, substantial processing overhead may be avoided.