A 250 m Direct Time-of-Flight Ranging System Based on a Synthesis of Sub-Ranging Images and a Vertical Avalanche Photo-Diodes (VAPD) CMOS Image Sensor

Hirose, Yutaka; Koyama, Shinzo; Ishii, Motonori; Saitou, Shigeru; Takemoto, Masato; Nosé, Yukihiko; Inoue, Akito; Sakata, Yusuke; Sugiura, Yuki; Konishi, Tatsuya; Usuda, Manabu; Kasuga, Shigetaka; Mori, M.; Odagawa, Akihiro; Tanaka, Tsuyoshi

doi:10.3390/s18113642

Cited by 11 publications

(6 citation statements)

References 9 publications

(10 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Rapid progress has been made in the development of SPAD-based complementary metal-oxide-semiconductor (CMOS) image sensors (CIS). Targeted applications include photon-counting imagers [5][6][7], scientific applications [8,9], and time-of-flight ranging sensors for autonomous driving systems [10][11][12]. In general, operation of a SPAD is comprised of three stages; (i) an idling stage; (ii) single-photon detection followed by a GM pulse generation; (iii) quenching the GM pulse.…”

Section: Introductionmentioning

confidence: 99%

Modeling and Analysis of Capacitive Relaxation Quenching in a Single Photon Avalanche Diode (SPAD) Applied to a CMOS Image Sensor

Inoue

Okino

Koyama

et al. 2020

Sensors

Self Cite

View full text Add to dashboard Cite

We present an analysis of carrier dynamics of the single-photon detection process, i.e., from Geiger mode pulse generation to its quenching, in a single-photon avalanche diode (SPAD). The device is modeled by a parallel circuit of a SPAD and a capacitance representing both space charge accumulation inside the SPAD and parasitic components. The carrier dynamics inside the SPAD is described by time-dependent bipolar-coupled continuity equations (BCE). Numerical solutions of BCE show that the entire process completes within a few hundreds of picoseconds. More importantly, we find that the total amount of charges stored on the series capacitance gives rise to a voltage swing of the internal bias of SPAD twice of the excess bias voltage with respect to the breakdown voltage. This, in turn, gives a design methodology to control precisely generated charges and enables one to use SPADs as conventional photodiodes (PDs) in a four transistor pixel of a complementary metal-oxide-semiconductor (CMOS) image sensor (CIS) with short exposure time and without carrier overflow. Such operation is demonstrated by experiments with a 6 µm size 400 × 400 pixels SPAD-based CIS designed with this methodology.

show abstract

Section: Introductionmentioning

confidence: 99%

Modeling and Analysis of Capacitive Relaxation Quenching in a Single Photon Avalanche Diode (SPAD) Applied to a CMOS Image Sensor

Inoue

Okino

Koyama

et al. 2020

Sensors

Self Cite

View full text Add to dashboard Cite

show abstract

“…9(a)). In a conventional VAPD-TOF system [2], [21], the sub-ranges are measured sequentially by pairs of emission and detection pulses with fixed delay (T d ) for each sub-range (Fig. 9(b)).…”

Section: B Concept Of Sub-range-synthesis (Srs) Methodsmentioning

confidence: 99%

“…Each VAPD biased at −26.0 V (the excess voltage is 1.2 V) generates a Geiger-mode pulse on single photon absorption. The Geiger-mode pulse is self-quenched by charge storage on capacitors of VAPD itself and of stray components (capacitive quenching (CQ)) [17], [18], [19], [20], [21]. The stored charges after each single photon detection are used as a signal of one count of the photon.…”

Section: B Precision Photon Counting Circuitsmentioning

confidence: 99%

A Nearly Interference-Free and Depth-Resolution-Configurable Time-of-Flight System Based on a Mega-Pixel Vertical Avalanche Photodiodes CMOS Image Sensor

Yamada

Ishii

Kasuga

et al. 2022

IEEE Open J. Circuits Syst.

Self Cite

View full text Add to dashboard Cite

We present a long range (∼250 m) time-of flight (TOF) system with suppressed (nearly-free) mutual-interference. The system is based on a 1296 × 960 pixels vertical avalanche photodiodes (VAPD) CMOS image sensor (CIS). Real-time long-range 3D-imaging with 30 fps speed (450 fps for 2D imaging) is demonstrated. Designs and operation principles of the core circuits, i.e., a photon counting circuit and a global shutter driver, are fully described. The ranging method is based on a sub-range synthesis (SRS) where a range is set by the phase of exposure pulses with respect to that of the light source of the system. The depth resolution is configurable in that the minimum sub-range width limited by the light source pulse width of 10 ns or 1.5 m can be reduced to a 10 cm by introducing an indirect-TOF operation. Furthermore, by employing a random flight timing (RFT), mutual-interference in raw signal level is suppressed by 35 dB when 2 cameras are simultaneously operated. By simulation, the present system is estimated to be tolerant up to a case of 27 cameras operation.INDEX TERMS Avalanche photodiode, vertical avalanche photodiode, time-of-flight, CMOS image sensor, photon counting, ranging, interference.

show abstract

“…In recent years, various imaging systems exploiting the time-resolving features of SPADs have been demonstrated with increasing spatial resolution. Prominent application domains of SPADs include time-of-flight (ToF) imaging [1][2][3] and biophotonics [4][5][6]. In particular, the use of ToF SPAD imagers for range-finding has gained increased interest from the automotive and mobile industries [7,8].…”

Section: Introductionmentioning

confidence: 99%

A Near-Infrared Enhanced Silicon Single-Photon Avalanche Diode With a Spherically Uniform Electric Field Peak

Sieleghem

Süss

Boulenc³

et al. 2021

IEEE Electron Device Lett.

View full text Add to dashboard Cite

A near-infrared (NIR) enhanced silicon single-photon avalanche diode (SPAD) fabricated in a customized 0.13 µm CMOS technology is presented. The SPAD has a depleted absorption volume of approximately 15 µm × 15 µm × 18 µm. Electrons generated in the absorption region are efficiently transported by drift to a central active avalanche region with a diameter of 2 µm. At the operating voltage, the active region contains a spherically uniform field peak, enabling the multiplication of electrons originating from all corners of the device. The advantages of the SPAD architecture include high NIR photon detection efficiency (PDE), drift-based transport, low afterpulsing, and compatibility with an integrated CMOS readout. A front-side illuminated device is fabricated and characterized. The SPAD has a PDE of 13% at wavelength 905 nm, an afterpulsing probability < 0.1% for a dead time of 13 ns, and a median dark count rate (DCR) of 840 Hz at room temperature. The device shows promising performance for time-of-flight applications that benefit from uniform NIR-sensitive SPAD arrays.

show abstract

A 250 m Direct Time-of-Flight Ranging System Based on a Synthesis of Sub-Ranging Images and a Vertical Avalanche Photo-Diodes (VAPD) CMOS Image Sensor

Cited by 11 publications

References 9 publications

Modeling and Analysis of Capacitive Relaxation Quenching in a Single Photon Avalanche Diode (SPAD) Applied to a CMOS Image Sensor

Modeling and Analysis of Capacitive Relaxation Quenching in a Single Photon Avalanche Diode (SPAD) Applied to a CMOS Image Sensor

A Nearly Interference-Free and Depth-Resolution-Configurable Time-of-Flight System Based on a Mega-Pixel Vertical Avalanche Photodiodes CMOS Image Sensor

A Near-Infrared Enhanced Silicon Single-Photon Avalanche Diode With a Spherically Uniform Electric Field Peak

Contact Info

Product

Resources

About