3D Time-of-flight Camera

First developments

The first developments in 3D Vision at SOI were done in the framework of the Opto3D project, with the development of an intelligent electro-optical sensor for driving scenarios detection and object recognition, finalized to automotive functions, such as pre-crash, in which the obstacles classification is very important. The system is based on a CMOS image device performing and indirect measure of the light time-of-flight using trains of short laser pulses [1].

2D and 3D image of a pedestrian crossing the street	Particular of the 3D camera mounting on a car

A 50x30-pixels array with background rejection operating in real-time has been successfully designed, achieving centimeter resolution in a range of few meters. The whole system has been also tested in the real environment, over a car driving in a test track.

Media download (click on the icon): the movie shows on a colored scale the 3D image of a hand in real-time on the right side. On the left side, instead, the same 3D is textured with the 2D image, which is taken during the typical operation and so available in realtime simultaneously with the depth image.

New sensor with 10um pixel pitch

The latest design in the SOI research unit about 3D sensors exploits a novel device to perform electro-optical demodulation of modulated light. The developed camera prototypes, have a resolution of 80x60 and 160x120 pixels with a record pitch of 10um, the smallest to date [2]. The operating principle is based on the use of modulated light, which allows using near-infrared LED to illuminate the scene. Cemtimeter resolution in real time has been obtained with the camera prototype.

Media download 1 (click on the icon): the movie shows on a colored scale the 3D image of a person with a panel in the background at a distance of about 2-3 meters from the sensor.

Media download 2 (click on the icon): the movie shows with the 2D texture and on a colored scale the 3D image of two hands in real-time moving at different distances.

References

[1] David Stoppa, Luigi Viarani, Andrea Simoni, Lorenzo Gonzo, Mattia Malfatti, Gianmaria Pedretti, "A 50x30-pixel CMOS Sensor for TOF-based Real Time 3D Imaging", 2005 Workshop on Charge-Coupled Devices and Advanced Image Sensors, IEEE, 2005, pp. 230-233, Nagano, Japan, 09/06/2005 - 11/06/2005 [link]

[2] David Stoppa, Nicola Massari, Lucio Pancheri, Mattia Malfatti, Matteo Perenzoni, and Lorenzo Gonzo, "An 80x60 Range Image Sensor based on 10um 50MHz Lock-In Pixels in 0.18um CMOS", International Solid-State Circuits Conference ISSCC 2010, San Francisco, 7-11 February, 2010 [link]

[3] Lucio Pancheri, David Stoppa, Nicola Massari, Mattia Malfatti, Lorenzo Gonzo, Quazi D. Hossain, Gian-Franco Dalla Betta, "A 160x120 pixel CMOS range image sensor based on current assisted photonic demodulators", SPIE Photonics Europe 2010 - Optical Sensing and Detection, Bruxelles, 2010  [link]