3D Time of Flight (ToF) | Analog Devices

Analog Devices 3D Time of Flight (ToF):

3D time of flight (ToF) is a type of scanner-less LIDAR (light detection and ranging) that uses high power optical pulses in durations of nanoseconds to capture depth information (typically over short distances) from a scene of interest.

ADI offers industry-leading products and solutions that enable and enhance industry-leading performance for ToF systems and cameras, including the highest resolution CMOS imaging chips (1 Megapixel), depth computation and processing, laser drivers, and power management, along with development tools and software/firmware to aid in the quick implementation of ToF solutions. In addition, ADI helps facilitate quick time-to-revenue by leveraging a global partner network in developing ToF modules, cameras, and design services.

Time of Flight Technology Overview

A ToF camera measures distance by actively illuminating an object with a modulated light source such as a laser and a sensor that is sensitive to the laser’s wavelength for capturing reflected light. The sensor measures the time delay ∆ between when the light is emitted and when the reflected light is received by the camera. The time delay is proportional to twice the distance between the camera and the object (round-trip), therefore the distance can be estimated as depth = cΔ/2 where c is the speed of light.

There are different methods for measuring ∆T, of which two have become the most prevalent: the continuous-wave (CW) method and the pulse-based method. It should be noted that the vast majority of CW ToF systems that have been implemented and are currently on the market use CMOS sensors, while pulsed ToF systems use non-CMOS sensors (notably CCDs).

ToF Simplified Diagram

Simple diagram of time of flight measurement.

ToF - Time of Flight

Example image of using time of flight measurement for people classification and range detection.

In partnership with Microsoft Corp., ADI is building out a new portfolio focused on CMOS CW-based products that complement our existing products for CCD pulsed-based systems. ADI is leveraging its technical expertise and building upon Microsoft’s Azure Kinect technology to deliver leading ToF solutions that offer the highest depth accuracy possible, operate over farther distances, and perform robustly across environments with minimal power consumption.

Delivering Value in Key Application Areas

Consumer

From AR (augmented reality) and VR (virtual reality) headsets to smartphones with advanced photographic and security features, ToF technology is projected to become a vital part of next-generation consumer electronics.

In AR/VR headsets, depth information acquired by the ToF system literally provides the user with an additional dimension of reality. In smartphones, the technology will enable cameras to develop DSLR-quality photographic effects, enable more realistic AR/VR features, and provide additional protection from unwanted external access.

Industry 4.0

The use of smart sensors, especially depth sensors, is becoming more and more ubiquitous within manufacturing, as well as transportation and logistics.

From industrial machine vision for quality inspection, to volumetric detection for asset management, to navigation for autonomous manufacturing, the manufacturing industry is adopting these sensing technologies and moving toward highest resolution systems designed for harsh industrial environments.

Automotive

In next-generation automobiles, ToF systems in the cabin will be able to monitor the position and the state of the driver and its passengers, taking over control and maneuvering the car to safety in cases where the driver becomes incapacitated.

Gesture control systems, made possible through ToF technology, are said to be the next-generation user interface for the car, allowing the driver to answer an incoming phone call, change an audio input source, or even adjust the climate control through simple gestures of the hand or fingers.

Healthcare

Time of flight technology for remote distance and depth measurement has become more important in healthcare in light of the recent pandemic. Contactless manipulation of controls through gestures, the remote monitoring of infant respiration, and the monitoring of social distancing in various environments are just some of the few applications in which ADI time of flight technology can be used.

Security and Surveillance

ADI's high resolution depth sensing technology offers significant advantages over traditional 2D image sensing techniques. High resolution depth makes it easier to classify both people and objects with much higher levels of confidence. This can be leveraged into many application use cases, from commercial/retail entry/exit (for security and surveillance) to detecting people falling or hurting themselves (for medical applications).

Robotics

High-resolution ToF systems will become essential in allowing autonomous machines and robotics to perceive their environment and plan their paths to optimally, reliably, and safely complete their tasks. Additionally, 3D imaging can enable safety features in applications where humans and collaborative robotics work together.

CMOS 3D - As easy as 1-2-3

For years ADI has been delivering components for 3D time-of-flight (ToF) imaging with proven solution in mass-production across consumer, automotive, and industrial applications. ADI is expanding that reach and delivering on a comprehensive roadmap of CMOS imagers, laser drivers, software- & hardware-based depth compute, and full solutions. Discover how ADI is taking on some of the deepest challenges in ToF to take the complicated work off our customers’ plates and letting them focus on enriching their applications.

Read the blog on EngineerZone

Time of Flight Products

ADSD3100

1 MP, CMOS, Time of Flight, Backside Illumination Sensor

Key Applications: High-resolution ToF imaging

ADDI9036

CCD TOF Signal Processor with Programmable Timing and V-Driver

Key Applications: ToF Processor

ADP3634

High Speed, Dual, 4 A MOSFET Driver, non-inverting A/B input pins, 9.5V < Vin < 18V

Key Applications: Laser Diode Driver

3D Time of Flight Development Platform

Modular ToF solution, built on the industry-standard 96Boards platform, which enables measuring objects in the X, Y, and Z axis.

Visit the AD-96TOF1-EBZ Product Page

3D Time of Flight Platform Makes Machine Perception a Reality

Analog Devices prototyping 3D ToF platform can be used for software and algorithm development. As a start for the hardware design, the platform can be used for more rapid evaluation and implementation in Industrial, Automotive, and more.

Watch the video about ADI's Depth-Sensing Technology

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