Abstract: An optoelectronic module operable to collect distance data via a time-of-flight mode and a time-of-flight-triangulation mode includes an illumination assembly and an imaging assembly. The imaging assembly includes at least one demodulation pixel operable to determine distance to an object via a time-of-flight mode and a time-of-flight-triangulation mode. Multi-path distance inaccuracies can be mitigated in some implementations.

Abstract: Optoelectronic modules (100) are operable to distinguish between signals indicative of reflections from an object of interest and signals indicative of a spurious reflection. Various modules are operable to recognize spurious reflections by means of dedicated spurious-reflection detection pixels (126) and, in some cases, also to compensate for errors caused by spurious reflections.

Abstract: A demodulation image sensor, such as used in time of flight (TOF) cameras, extracts all storage- and post-processing-related steps from the pixels to another array of storage and processing elements (proxels) on the chip. The pixel array has the task of photo-detection, first processing and intermediate storage, while the array of storage and processing elements provides further processing and enhanced storage capabilities for each pixel individually. The architecture can be used to address problems due to the down-scaling of the pixel size. Typically, either the photo-sensitivity or the signal storage capacitance suffers significantly. Both a lower sensitivity and smaller storage capacitances have negative influence on the image quality. The disclosed architecture allows for keeping the storage capacitance unaffected by the pixel down-scaling. In addition to that, it provides a high degree of flexibility in integrating more intelligence into the image sensor design already on the level of the pixel array.

Abstract: The modulation scheme disclosed in this invention report allows for utilizing multiple 3D time-of-flight cameras at the same time by exploiting the inherent pseudo noise properties of the optical modulation signals. Compared to recent systems based on pure pseudo noise modulation signals, the stochastic measurement error in a single-camera environment is significantly reduced. The basic concept relies on the generation of a three level optical modulation signal that includes two pseudo noise sequences.

Abstract: A novel photo-sensitive element for electronic imaging purposes and, in this context, is particularly suited for time-of-flight 3D imaging sensor pixels. The element enables charge-domain photo-detection and processing based on a single gate architecture. Certain regions for n and p-doping implants of the gates are defined. This kind of single gate architecture enables low noise photon detection and high-speed charge transport methods at the same time. A strong benefit compared to known pixel structures is that no special processing steps are required such as overlapping gate structures or very high-ohmic poly-silicon deposition. In this sense, the element relaxes the processing methods so that this device may be integrated by the use of standard CMOS technology for example. Regarding time-of-flight pixel technology, a major challenge is the generation of lateral electric fields. The element allows the generation of fringing fields and large lateral electric fields.

Abstract: A demodulation image sensor, such as used in time of flight (TOF) cameras, extracts all storage- and post-processing-related steps from the pixels to another array of storage and processing elements (proxels) on the chip. The pixel array has the task of photo-detection, first processing and intermediate storage to create subframes, while the array of storage and processing elements provides accumulation into frames. Particularly, sampled values of several subframes are summed in a compressed manner. Possible compression is to use exponential function.

Abstract: The presented readout structure provides charge transport based readout of a photosensitive device with a minimum number of transport gates. The structure uses the given charge storage buckets of the photosensitive device, separated by a minimum sized barrier-gate, to transport the charge out of the pixel field. This new readout schema allows for a fast readout speed based on a 2 phase transport chain and increases the pixel's optical fill factor by significantly reducing the transport gate size compared to state-of-the-art pixels using a 3 or 4 phase CCD readout chain. This readout structure can be exploited for standard photo-detecting elements such as e.g. pinned photo-diodes or any enhanced pixel structure that has additional intelligence incorporated as well. Typical applications are 2D- or 3D-imaging.

Abstract: An increased sense node capacitance, mainly for 3D time-of-flight (TOF) applications, includes a storage structure that combines the advantages of gate and diffusion capacitance in order to improve the overall capacitance. The storage structure provides higher capacitance per unit area and accordingly a better fill-factor/sensitivity of the pixel; improved noise behaviour because of the use of gate capacitances, better protection against interacting signals and thus better signal quality.

Abstract: A demodulation image sensor, such as used in time of flight (TOF) cameras, performs the acquisition and readout of the pixels in parallel. This is used to avoid motion artifacts due to samplings performed separated in time.

Abstract: A demodulation structure for a n-tap pixel, mainly for 3D time-of-flight (TOF) applications uses a 2-stage switch structure for demodulating a modulated electromagnetic wave. An almost arbitrary number of storage sites per pixel can be implemented enabling an almost arbitrary number of samplings captured during one exposure. It also provides the option to demodulate and integrate different phasing samples according to the different modulation frequencies within the same exposure.

Abstract: A novel photo-sensitive element for electronic imaging purposes and, in this context, is particularly suited for time-of-flight 3D imaging sensor pixels. The element enables charge-domain photo-detection and processing based on a single gate architecture. Certain regions for n and p-doping implants of the gates are defined. This kind of single gate architecture enables low noise photon detection and high-speed charge transport methods at the same time. A strong benefit compared to known pixel structures is that no special processing steps are required such as overlapping gate structures or very high-ohmic poly-silicon deposition. In this sense, the element relaxes the processing methods so that this device may be integrated by the use of standard CMOS technology for example. Regarding time-of-flight pixel technology, a major challenge is the generation of lateral electric fields. The element allows the generation of fringing fields and large lateral electric fields.

Abstract: A method for filtering distance information from a 3D-measurement camera system comprises comparing amplitude and/or distance information for pixels to adjacent pixels and averaging distance information for the pixels with the adjacent pixels when amplitude and/or distance information for the pixels is within a range of the amplitudes and/or distances for the adjacent pixels. In addition to that the range of distances may or may not be defined as a function depending on the amplitudes.

Abstract: A modulation technique for 3D time-of-flight (TOF) cameras allows the operation of fully autonomous operated 3D TOF cameras. The method subdivides the exposure time into several sub-exposure intervals, for which the signal control unit adds a preferably pseudo-random common phase delay to the illumination and the sensor.

Abstract: A new pixel in semiconductor technology comprises a photo-sensitive detection region (1) for converting an electromagnetic wave field into an electric signal of flowing charges, a separated demodulation region (2) with at least two output nodes (D10, D20) and means (IG10, DG10, IG20, DG20) for sampling the charge-current signal at least two different time intervals within a modulation period. A contact node (K2) links the detection region (1) to the demodulation region (2). A drift field accomplishes the transfer of the electric signal of flowing charges from the detection region to the contact node. The electric signal of flowing charges is then transferred from the contact node (K2) during each of the two time intervals to the two output nodes allocated to the respective time interval. The separation of the demodulation and the detection regions provides a pixel capable of demodulating electromagnetic wave field at high speed and with high sensitivity.

Abstract: A method to compensate for multi-path in time-of-flight (TOF) three dimensional (3D) cameras applies different modulation frequencies in order to calculate/estimate the error vector. Multi-path in 3D TOF cameras might be caused by one of the two following sources: stray light artifacts in the TOF camera systems and multiple reflections in the scene. The proposed method compensates for the errors caused by both sources by implementing multiple modulation frequencies.

Abstract: The modulation scheme disclosed in this invention report allows for utilizing multiple 3D time-of-flight cameras at the same time by exploiting the inherent pseudo noise properties of the optical modulation signals. Compared to recent systems based on pure pseudo noise modulation signals, the stochastic measurement error in a single-camera environment is significantly reduced. The basic concept relies on the generation of a three level optical modulation signal that includes two pseudo noise sequences.

Abstract: A demodulation structure for a n-tap pixel, mainly for 3D time-of-flight (TOF) applications uses a 2-stage switch structure for demodulating a modulated electromagnetic wave. An almost arbitrary number of storage sites per pixel can be implemented enabling an almost arbitrary number of samplings captured during one exposure. It also provides the option to demodulate and integrate different phasing samples according to the different modulation frequencies within the same exposure.

Abstract: A demodulation image sensor, such as used in time of flight (TOF) cameras, extracts all storage- and post-processing-related steps from the pixels to another array of storage and processing elements (proxels) on the chip. The pixel array has the task of photo-detection, first processing and intermediate storage, while the array of storage and processing elements provides further processing and enhanced storage capabilities for each pixel individually. The architecture can be used to address problems due to the down-scaling of the pixel size. Typically, either the photo-sensitivity or the signal storage capacitance suffers significantly. Both a lower sensitivity and smaller storage capacitances have negative influence on the image quality. The disclosed architecture allows for keeping the storage capacitance unaffected by the pixel down-scaling. In addition to that, it provides a high degree of flexibility in integrating more intelligence into the image sensor design already on the level of the pixel array.

Abstract: A new pixel in semiconductor technology comprises a photo-sensitive detection region (1) for converting an electromagnetic wave field into an electric signal of flowing charges, a separated demodulation region (2) with at least two output nodes (D10, D20) and means (IG10, DG10, IG20, DG20) for sampling the charge-current signal at least two different time intervals within a modulation period. A contact node (K2) links the detection region (1) to the demodulation region (2). A drift field accomplishes the transfer of the electric signal of flowing charges from the detection region to the contact node. The electric signal of flowing charges is then transferred from the contact node (K2) during each of the two time intervals to the two output nodes allocated to the respective time interval. The separation of the demodulation and the detection regions provides a pixel capable of demodulating electromagnetic wave field at high speed and with high sensitivity.

Abstract: A demodulation pixel improves the charge transport speed and sensitivity by exploiting two effects of charge transport in silicon in order to achieve the before-mentioned optimization. The first one is a transport method based on the CCD gate principle. However, this is not limited to CCD technology, but can be realized also in CMOS technology. The charge transport in a surface or even a buried channel close to the surface is highly efficient in terms of speed, sensitivity and low trapping noise. In addition, by activating a majority carrier current flowing through the substrate, another drift field is generated below the depleted CCD channel. This drift field is located deeply in the substrate, acting as an efficient separator for deeply photo-generated electron-hole pairs. Thus, another large amount of minority carriers is transported to the diffusion nodes at high speed and detected.