The Experts below are selected from a list of 198 Experts worldwide ranked by ideXlab platform
Edoardo Charbon - One of the best experts on this subject based on the ideXlab platform.
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a 160 128 single photon image sensor with on pixel 55ps 10b time to digital converter
International Solid-State Circuits Conference, 2011Co-Authors: Chockalingam Veerappan, Justin Richardson, R Walker, Matthew W Fishburn, Yuki Maruyama, David Stoppa, F Borghetti, Marek Gersbach, Robert Henderson, Edoardo CharbonAbstract:Image sensors capable of resolving the time-of-arrival (ToA) of individual photons with high resolution are needed in several applications, such as fluorescence lifetime imaging microscopy (FLIM), Forster resonance energy transfer (FRET), optical Rangefinding, and positron emission tomography. In FRET, for example, typical fluorescence lifetime is of the order of 100 to 300ps, thus deep-subnanosecond resolutions are needed in the instrument response function (IRF). This in turn requires new time-resolved image sensors with better time resolution, increased throughput, and lower costs. Solid-state avalanche photodiodes operated in Geiger-mode, or single-photon avalanche diodes (SPADs), have existed for decades [1] but only recently have SPADs been integrated in CMOS. However, as array sizes have grown, the readout bottleneck has also become evident, leading to hybrid designs or more integration and more parallelism on-chip [2,3]. This trend has accelerated with the introduction of SPAD devices in deep-submicron CMOS, that have enabled the design of massively parallel arrays where the entire photon detection and ToA circuitry is integrated on-pixel [4,5].
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a 128 times 128 single photon image sensor with column level 10 bit time to digital converter array
IEEE Journal of Solid-state Circuits, 2008Co-Authors: Cristiano Niclass, Marek Gersbach, C Favi, Theo Kluter, Edoardo CharbonAbstract:An imager for time-resolved optical sensing was fabricated in CMOS technology. The sensor comprises an array of 128times128 single-photon pixels, a bank of 32 time-to-digital-converters, and a 7.68 Gbps readout system. Thanks to the outstanding timing precision of single-photon avalanche diodes and the optimized measurement circuitry, a typical resolution of 97 ps was achieved within a range of 100 ns. To the best of our knowledge, this imager is the first fully integrated system for photon time-of-arrival evaluation. Applications include 3-D imaging, optical Rangefinding, fast fluorescence lifetime imaging, imaging of extremely fast phenomena, and, more generally, imaging based on time-correlated single photon counting. When operated as an optical rangefinder, this design has enabled us to reconstruct 3-D scenes with milimetric precisions in extremely low signal exposure. A laser source was used to illuminate the scene up to 3.75 m with an average power of 1 mW, a field-of-view of 5deg and under 150 lux of constant background light. Accurate distance measurements were repeatedly achieved based on a short integration time of 50 ms even when signal photon count rates as low as a few hundred photons per second were available.
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design and characterization of a cmos 3 d image sensor based on single photon avalanche diodes
IEEE Journal of Solid-state Circuits, 2005Co-Authors: Cristiano Niclass, Alexis Rochas, P A Besse, Edoardo CharbonAbstract:The design and characterization of an imaging system is presented for depth information capture of arbitrary three-dimensional (3-D) objects. The core of the system is an array of 32 /spl times/ 32 Rangefinding pixels that independently measure the time-of-flight of a ray of light as it is reflected back from the objects in a scene. A single cone of pulsed laser light illuminates the scene, thus no complex mechanical scanning or expensive optical equipment are needed. Millimetric depth accuracies can be reached thanks to the rangefinder's optical detectors that enable picosecond time discrimination. The detectors, based on a single photon avalanche diode operating in Geiger mode, utilize avalanche multiplication to enhance light detection. On-pixel high-speed electrical amplification can therefore be eliminated, thus greatly simplifying the array and potentially reducing its power dissipation. Optical power requirements on the light source can also be significantly relaxed, due to the array's sensitivity to single photon events. A number of standard performance measurements, conducted on the imager, are discussed in the paper. The 3-D imaging system was also tested on real 3-D subjects, including human facial models, demonstrating the suitability of the approach.
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Design and characterization of a CMOS 3-D image sensor based on single photon avalanche diodes
IEEE Journal of Solid-State Circuits, 2005Co-Authors: Cristiano Niclass, Alexis Rochas, P A Besse, Edoardo CharbonAbstract:The design and characterization of an imaging system is presented for depth information capture of arbitrary three-dimensional (3-D) objects. The core of the system is an array of 32 × 32 Rangefinding pixels that independently measure the time-of-flight of a ray of light as it is reflected back from the objects in a scene. A single cone of pulsed laser light illuminates the scene, thus no complex mechanical scanning or expensive optical equipment are needed. Millimetric depth accuracies can be reached thanks to the rangefinder's optical detectors that enable picosecond time discrimination. The detectors, based on a single photon avalanche diode operating in Geiger mode, utilize avalanche multiplication to enhance light detection. On-pixel high-speed electrical amplification can therefore be eliminated, thus greatly simplifying the array and potentially reducing its power dissipation. Optical power requirements on the light source can also be significantly relaxed, due to the array's sensitivity to single photon events. A number of standard performance measurements, conducted on the imager, are discussed in the paper. The 3-D imaging system was also tested on real 3-D subjects, including human facial models, demonstrating the suitability of the approach.
Juha Kostamovaara - One of the best experts on this subject based on the ideXlab platform.
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on two dimensional Rangefinding using a 1 nj 100 ps laser diode transmitter and a cmos spad matrix
IEEE Photonics Journal, 2018Co-Authors: Lauri Hallman, Sahba Jahromi, Jussipekka Jansson, Juha KostamovaaraAbstract:A potentially compact 2-D range profiler for noncooperative targets with a distance range of >10 m is demonstrated. A laser diode utilizing enhanced gain switching is used as a transmitter to provide short, high-energy optical pulses (~1 nJ/140 ps). Cylindrical lenses spread the laser beam in one dimension and collimate the beam in the other dimension to illuminate a line shaped field of view of about 45°. A similarly shaped field of view for the detector is realized with a single-photon avalanche diode (SPAD) detector matrix. Compared with a flash 3-D rangefinder, the 2-D Rangefinding scheme relaxes the SPAD and time-to-digital converter design requirements, increases the signal irradiance at the detector, can have better tolerance for background illumination, and it can be sufficient or advantageous in some applications. The distance measurement precision to each direction is inherently within a few centimeters (FWHM) since the laser pulse width and SPAD detector jitter both correspond with an optical pulse back-and-forth flight time of about a centimeter. Demonstration measurements show >15 Hz line rate and a lateral resolution of about 5 mrad to noncooperative targets at distances of more than 10 m.
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pulsed tof laser Rangefinding with a 2d spad tdc receiver
IEEE Sensors, 2015Co-Authors: Sahba Jahromi, Jp Jansson, Juha KostamovaaraAbstract:A pulsed time-of-flight laser radar based on a high speed/energy optical transmitter and a SPAD-TDC receiver is presented. The transmitter employs a bulk double heterostructure laser diode operating in enhanced gain switching mode at a wavelength of ∼870nm, giving ∼1nJ/125ps optical pulses. The receiver is a single CMOS chip consisting of a 9×9 CMOS SPAD array and a 10-channel 10ps precision TDC. The 2D detector array releases the required precision and tolerances of the opto-mechanics of the radar. Any of the 3×3 sub-arrays within the 9×9 array can be selected for simultaneous measurement, and the selection can be altered flexibly during measurements, e.g. to follow movements of the target image at the detector surface. Adjustable-width time-gating windows of down to ∼5ns can be used to suppress background hits. A single shot precision of ∼170ps (FWHM) and a measurement range of tens of metres with non-cooperative targets have been achieved with an 18mm receiver aperture.
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a multi channel wide range time to digital converter with better than 9ps rms precision for pulsed time of flight laser Rangefinding
European Solid-State Circuits Conference, 2012Co-Authors: Jussipekka Jansson, Antti Mantyniemi, Juha KostamovaaraAbstract:A multi-channel time-to-digital converter has been realized in 0.35μm CMOS. The 7-channel converter is based on a multiplying delay-locked loop acting as a first and a capacitor-scaled parallel delay line as a second interpolator, and is able to measure the time intervals and pulse widths or rise times of several successive timing signals. The circuit utilizes a 20MHz external crystal as a time base and offers better than 9ps measurement precision and a measurement range of up to ±74μs.
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a 2 channel cmos time to digital converter for time of flight laser Rangefinding
Instrumentation and Measurement Technology Conference, 2009Co-Authors: Ilkka Nissinen, Juha KostamovaaraAbstract:A time-to-digital converter (TDC) based on a free running ring oscillator and timing signal interpolators has been fabricated in a 0.13 μm CMOS process for the receiver of a pulsed time-of-flight laser rangefinder (TOF). The time-to-digital conversion is based on counting the pulses of this eighth-stage, differential ring oscillator and additionally registering the state of its 16 phases at the arrival moment of the timing signals and their delayed replicas. The temperature and supply voltage dependences of the ring oscillator are compensated for by measuring its frequency by means of an accurate time generator. The single-shot precision standard deviation value and the nonlinearity of the TDC are less than 20 ps (3 mm) and ±16 ps (2.4 mm), respectively, in the distance range of 0 to 15 m. The power consumption is less than 16 mW.
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a wide dynamic range receiver channel for a pulsed time of flight laser radar
IEEE Journal of Solid-state Circuits, 2001Co-Authors: Tarmo Ruotsalainen, P. Palojarvi, Juha KostamovaaraAbstract:An integrated receiver channel for a pulsed time-of-flight (TOF) laser rangefinder has been designed and tested. The bandwidth of the receiver channel is 170 MHz, the transimpedance can be controlled in the range from 1.1 k/spl Omega/ to 260 k/spl Omega/, and the input-referred noise is /spl sim/6 pA//spl radic/Hz. The distance measurement accuracy is /spl plusmn/4.7 mm (average of 10000 measurements), taking into account walk error (input signal amplitude varies in the range 1:624) and jitter. A considerable increase in the input dynamic range of the receiver has been achieved by placing an integrated current buffer with variable attenuation between the external photodetector and the transimpedance preamplifier. Integrated electronic gain control structures together with the small size and low power consumption achieved by the use of full custom integrated technology considerably simplifies Rangefinding devices for many applications. The circuit was implemented in an 0.8-/spl mu/m BiCMOS process.
Cristiano Niclass - One of the best experts on this subject based on the ideXlab platform.
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a 128 times 128 single photon image sensor with column level 10 bit time to digital converter array
IEEE Journal of Solid-state Circuits, 2008Co-Authors: Cristiano Niclass, Marek Gersbach, C Favi, Theo Kluter, Edoardo CharbonAbstract:An imager for time-resolved optical sensing was fabricated in CMOS technology. The sensor comprises an array of 128times128 single-photon pixels, a bank of 32 time-to-digital-converters, and a 7.68 Gbps readout system. Thanks to the outstanding timing precision of single-photon avalanche diodes and the optimized measurement circuitry, a typical resolution of 97 ps was achieved within a range of 100 ns. To the best of our knowledge, this imager is the first fully integrated system for photon time-of-arrival evaluation. Applications include 3-D imaging, optical Rangefinding, fast fluorescence lifetime imaging, imaging of extremely fast phenomena, and, more generally, imaging based on time-correlated single photon counting. When operated as an optical rangefinder, this design has enabled us to reconstruct 3-D scenes with milimetric precisions in extremely low signal exposure. A laser source was used to illuminate the scene up to 3.75 m with an average power of 1 mW, a field-of-view of 5deg and under 150 lux of constant background light. Accurate distance measurements were repeatedly achieved based on a short integration time of 50 ms even when signal photon count rates as low as a few hundred photons per second were available.
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design and characterization of a cmos 3 d image sensor based on single photon avalanche diodes
IEEE Journal of Solid-state Circuits, 2005Co-Authors: Cristiano Niclass, Alexis Rochas, P A Besse, Edoardo CharbonAbstract:The design and characterization of an imaging system is presented for depth information capture of arbitrary three-dimensional (3-D) objects. The core of the system is an array of 32 /spl times/ 32 Rangefinding pixels that independently measure the time-of-flight of a ray of light as it is reflected back from the objects in a scene. A single cone of pulsed laser light illuminates the scene, thus no complex mechanical scanning or expensive optical equipment are needed. Millimetric depth accuracies can be reached thanks to the rangefinder's optical detectors that enable picosecond time discrimination. The detectors, based on a single photon avalanche diode operating in Geiger mode, utilize avalanche multiplication to enhance light detection. On-pixel high-speed electrical amplification can therefore be eliminated, thus greatly simplifying the array and potentially reducing its power dissipation. Optical power requirements on the light source can also be significantly relaxed, due to the array's sensitivity to single photon events. A number of standard performance measurements, conducted on the imager, are discussed in the paper. The 3-D imaging system was also tested on real 3-D subjects, including human facial models, demonstrating the suitability of the approach.
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Design and characterization of a CMOS 3-D image sensor based on single photon avalanche diodes
IEEE Journal of Solid-State Circuits, 2005Co-Authors: Cristiano Niclass, Alexis Rochas, P A Besse, Edoardo CharbonAbstract:The design and characterization of an imaging system is presented for depth information capture of arbitrary three-dimensional (3-D) objects. The core of the system is an array of 32 × 32 Rangefinding pixels that independently measure the time-of-flight of a ray of light as it is reflected back from the objects in a scene. A single cone of pulsed laser light illuminates the scene, thus no complex mechanical scanning or expensive optical equipment are needed. Millimetric depth accuracies can be reached thanks to the rangefinder's optical detectors that enable picosecond time discrimination. The detectors, based on a single photon avalanche diode operating in Geiger mode, utilize avalanche multiplication to enhance light detection. On-pixel high-speed electrical amplification can therefore be eliminated, thus greatly simplifying the array and potentially reducing its power dissipation. Optical power requirements on the light source can also be significantly relaxed, due to the array's sensitivity to single photon events. A number of standard performance measurements, conducted on the imager, are discussed in the paper. The 3-D imaging system was also tested on real 3-D subjects, including human facial models, demonstrating the suitability of the approach.
P. Palojarvi - One of the best experts on this subject based on the ideXlab platform.
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a wide dynamic range receiver channel for a pulsed time of flight laser radar
IEEE Journal of Solid-state Circuits, 2001Co-Authors: Tarmo Ruotsalainen, P. Palojarvi, Juha KostamovaaraAbstract:An integrated receiver channel for a pulsed time-of-flight (TOF) laser rangefinder has been designed and tested. The bandwidth of the receiver channel is 170 MHz, the transimpedance can be controlled in the range from 1.1 k/spl Omega/ to 260 k/spl Omega/, and the input-referred noise is /spl sim/6 pA//spl radic/Hz. The distance measurement accuracy is /spl plusmn/4.7 mm (average of 10000 measurements), taking into account walk error (input signal amplitude varies in the range 1:624) and jitter. A considerable increase in the input dynamic range of the receiver has been achieved by placing an integrated current buffer with variable attenuation between the external photodetector and the transimpedance preamplifier. Integrated electronic gain control structures together with the small size and low power consumption achieved by the use of full custom integrated technology considerably simplifies Rangefinding devices for many applications. The circuit was implemented in an 0.8-/spl mu/m BiCMOS process.
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pn photodiodes for pulsed laser Rangefinding applications realized in standard cmos bicmos processes
Analog Integrated Circuits and Signal Processing, 2001Co-Authors: P. Palojarvi, Tarmo Ruotsalainen, Juha KostamovaaraAbstract:This paper describes simulation of the operation of integrated high-speed pn photodiodes and verification of the results by means of measurements performed with two types of photodiode, one implemented in a standard 0.8 μm CMOS process and the other in a standard 1.2 μm BiCMOS process. The measured rise times and responsivities of the photodiodes were <5 ns and 0.28 A/W in the CMOS process and 30 ns and 0.31 A/W in the BiCMOS process. Furthermore, the suitability of the photodiode for 3D vision was investigated by designing an array of photodetectors and measuring the isolation between the detector blocks. The results confirm that the photodetectors and receiver for a pulsed laser rangefinder can be implemented on the same chip in a standard process without any process modifications.
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A new approach to avoid walk error in pulsed laser Rangefinding
1999 IEEE International Symposium on Circuits and Systems (ISCAS), 1999Co-Authors: P. Palojarvi, T. Ruotsalainen, J. KostamovaaraAbstract:In this paper a new way to combine timing discrimination and time interval measurement in pulsed laser Rangefinding is presented. The aim is to eliminate the dependency of amplitude from the timing result, i.e. walk error. The idea is based on a time-to-amplitude converter where the input transistors are used as "soft switches" by controlling them with an analog input signal. The principle of the operation has been presented together with measurement results of a test circuit implemented in a 0.8 /spl mu/m BiCMOS process. A measured walk error of /spl plusmn/3.5 ps has been achieved with the input signal dynamic range of 1:19.
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bicmos and cmos timing detectors for the receiver of a portable laser Rangefinding device
Midwest Symposium on Circuits and Systems, 1995Co-Authors: Tarmo Ruotsalainen, P. Palojarvi, Juha KostamovaaraAbstract:Integrated CMOS and BiCMOS timing detectors have been designed for the receiver of a portable laser radar. The timing detectors produce accurately timed logic level pulses from noisy analog pulses, whose amplitude varies in a wide range. The distance measurement result of the designed BiCMOS (CMOS) detector varies +/-4 mm (+/-9 mm) with an input amplitude range of 55 mV-3.3 V (0.5 V-2.2 V). The single shot resolution with SNR=250 is better than 6 mm (10.5 mm).
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a 160 mhz bicmos differential amplifier channel with gain control for the receiver of a portable laser Rangefinding device
Midwest Symposium on Circuits and Systems, 1995Co-Authors: Tarmo Ruotsalainen, P. Palojarvi, Juha KostamovaaraAbstract:A differential BiCMOS linear amplifier channel with gain control and a peak detector have been designed for a pulsed time-of-flight laser radar. The bandwidth of the amplifier channel is /spl sim/160 MHz and its gain can be controlled with a variable R-2R ladder attenuator in 7 discrete steps from 0.44 to 23. The peak detector can detect the peak of a single 10 ns pulse, the amplitude of which is varying from 50 mV to 3.5 V.
Alexis Rochas - One of the best experts on this subject based on the ideXlab platform.
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design and characterization of a cmos 3 d image sensor based on single photon avalanche diodes
IEEE Journal of Solid-state Circuits, 2005Co-Authors: Cristiano Niclass, Alexis Rochas, P A Besse, Edoardo CharbonAbstract:The design and characterization of an imaging system is presented for depth information capture of arbitrary three-dimensional (3-D) objects. The core of the system is an array of 32 /spl times/ 32 Rangefinding pixels that independently measure the time-of-flight of a ray of light as it is reflected back from the objects in a scene. A single cone of pulsed laser light illuminates the scene, thus no complex mechanical scanning or expensive optical equipment are needed. Millimetric depth accuracies can be reached thanks to the rangefinder's optical detectors that enable picosecond time discrimination. The detectors, based on a single photon avalanche diode operating in Geiger mode, utilize avalanche multiplication to enhance light detection. On-pixel high-speed electrical amplification can therefore be eliminated, thus greatly simplifying the array and potentially reducing its power dissipation. Optical power requirements on the light source can also be significantly relaxed, due to the array's sensitivity to single photon events. A number of standard performance measurements, conducted on the imager, are discussed in the paper. The 3-D imaging system was also tested on real 3-D subjects, including human facial models, demonstrating the suitability of the approach.
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Design and characterization of a CMOS 3-D image sensor based on single photon avalanche diodes
IEEE Journal of Solid-State Circuits, 2005Co-Authors: Cristiano Niclass, Alexis Rochas, P A Besse, Edoardo CharbonAbstract:The design and characterization of an imaging system is presented for depth information capture of arbitrary three-dimensional (3-D) objects. The core of the system is an array of 32 × 32 Rangefinding pixels that independently measure the time-of-flight of a ray of light as it is reflected back from the objects in a scene. A single cone of pulsed laser light illuminates the scene, thus no complex mechanical scanning or expensive optical equipment are needed. Millimetric depth accuracies can be reached thanks to the rangefinder's optical detectors that enable picosecond time discrimination. The detectors, based on a single photon avalanche diode operating in Geiger mode, utilize avalanche multiplication to enhance light detection. On-pixel high-speed electrical amplification can therefore be eliminated, thus greatly simplifying the array and potentially reducing its power dissipation. Optical power requirements on the light source can also be significantly relaxed, due to the array's sensitivity to single photon events. A number of standard performance measurements, conducted on the imager, are discussed in the paper. The 3-D imaging system was also tested on real 3-D subjects, including human facial models, demonstrating the suitability of the approach.
