Depth Resolution Enhancement Technique for CMOS Time-of-Flight 3-D Image Sensors

Hafiane, Mohamed Lamine; Wagner, Wilfried; Dibi, Z.; Manck, O.

doi:10.1109/jsen.2012.2187350

Cited by 9 publications

(9 citation statements)

References 19 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…As in [ 2 ], this design allows only one measurement out of the several ones needed for ToF calculation, and the pixels must be reset and the light signal repeated to perform the rest of the measurements. In [ 15 ], this problem is avoided by including two photodiodes per pixel. This way, one of them can be reset, while the other is measuring the light signal.…”

Section: Related Workmentioning

confidence: 99%

“…To do so, it is necessary to take into account that the ToF pixel can be implemented in either voltage or current mode, shown respectively in Figures 4 and 5 for 1B techniques, without loss of generality. In voltage mode, the photocharges of each x i measurement are accumulated in an intermediate capacitor (which can be the photosensor itself) transforming the charge signal into a voltage one, [ 14 , 15 ]. This mode of operation has the disadvantage of requiring the resetting of the intermediate capacitor before each x i measurement.…”

Section: Signal Accumulationmentioning

confidence: 99%

See 1 more Smart Citation

Distance Measurement Error in Time-of-Flight Sensors Due to Shot Noise

Illade-Quinteiro

Brea

López

et al. 2015

Sensors

View full text Add to dashboard Cite

Unlike other noise sources, which can be reduced or eliminated by different signal processing techniques, shot noise is an ever-present noise component in any imaging system. In this paper, we present an in-depth study of the impact of shot noise on time-of-flight sensors in terms of the error introduced in the distance estimation. The paper addresses the effect of parameters, such as the size of the photosensor, the background and signal power or the integration time, and the resulting design trade-offs. The study is demonstrated with different numerical examples, which show that, in general, the phase shift determination technique with two background measurements approach is the most suitable for pixel arrays of large resolution.

show abstract

Section: Related Workmentioning

confidence: 99%

Section: Signal Accumulationmentioning

confidence: 99%

Distance Measurement Error in Time-of-Flight Sensors Due to Shot Noise

Illade-Quinteiro

Brea

López

et al. 2015

Sensors

View full text Add to dashboard Cite

show abstract

“…Other pixels presented in the literature use this technique with only 3 measurements, x 1 , x 2 , and x 3 ; see, for example, Perenzoni et al Another technique for pulsed ToF, called multiple double short time integration, exists . This technique is similar to the one presented here except for the length and synchronization of the x 2 integration.…”

Section: Tof Operationmentioning

confidence: 93%

“…For this reason, larger photosensing devices are needed, and, also, the received signal must be enhanced by extra circuitry. Examples of this are Elkhalili et al and Hafiane et al, where 2 photosensors per pixel are used so one can receive the light signal while the other is being reset. A different approach can be found in Perenzoni et al, where each measurement is first accumulated in the photodiode and, later, amplified and sent to a storage capacitor.…”

Section: Introductionmentioning

confidence: 99%

Pulsed time‐of‐flight pixel with on‐chip 20 klux background light suppression in standard CMOS technology

Illade-Quinteiro

López

Brea

et al. 2017

Circuit Theory & Apps

View full text Add to dashboard Cite

A novel time-of-flight pixel designed in 0.18-m standard CMOS technology with an indirect pulsed technique is presented. This design is capable of operating in ambients with high levels of background light, since a novel in-pixel background suppression circuit makes it robust up to 20 klux of ambient light.In addition to this, the pixel incorporates an adaptive number of accumulations circuit that selects the optimum number of accumulations for each situation at pixel level, avoiding saturation even under high illumination conditions. KEYWORDS 3D sensor, optical sensor, standard CMOS technology, time of flight Int J Circ Theor Appl. 2018;46:987-1005.wileyonlinelibrary.com/journal/cta

show abstract

“…8, the offsets are contributed by the buffer as well as by the comparator. Their impact can be addressed by resorting to cancellation schemes, such as correlated double sampling [39]. However, these techniques are useless in our case because they rely on subtracting images and hence would require linear coding.…”

Section: A Auto-zeroing Reset Techniquementioning

confidence: 99%

A 151 dB High Dynamic Range CMOS Image Sensor Chip Architecture With Tone Mapping Compression Embedded In-Pixel

2015

View full text Add to dashboard Cite

This paper presents a high dynamic range CMOS image sensor that implements an in-pixel content-aware adaptive global tone mapping algorithm during image capture operation. The histogram of the previous frame of an auxiliary image, which contains time stamp information, is employed as an estimation of the probability of illuminations impinging pixels at the present frame. The compression function of illuminations, namely tone mapping curve, is calculated using this histogram. A QCIF resolution proof-of-concept prototype has been fabricated using a 0.35 µm opto-flavored standard technology. The sensor is capable of mapping scenes with a maximum intra-frame dynamic range of 151 dB (25 bits/pixel in linear representation) by compressing them to only 7 bits/pixel, while keeping visual quality in details and contrast. The in-pixel on-the-fly fully parallel tone mapping achieves high-frame rate allowing real-time high dynamic range video (120 dB at 30 frames/s).Index Terms-CMOS image sensor, high dynamic range, tone mapping, pulse width modulation, real-time HDR video.

show abstract

Depth Resolution Enhancement Technique for CMOS Time-of-Flight 3-D Image Sensors

Cited by 9 publications

References 19 publications

Distance Measurement Error in Time-of-Flight Sensors Due to Shot Noise

Distance Measurement Error in Time-of-Flight Sensors Due to Shot Noise

Pulsed time‐of‐flight pixel with on‐chip 20 klux background light suppression in standard CMOS technology

A 151 dB High Dynamic Range CMOS Image Sensor Chip Architecture With Tone Mapping Compression Embedded In-Pixel

Contact Info

Product

Resources

About