With roots firmly established by the pioneering Microsoft Xbox Kinect gaming console, advanced 3D sensing technology has quickly become an elemental facet of modern society. Underpinning this new era of 3D expansion are the core innovations that empower safe, accurate, and efficient use of 3D sensing on a massive global scale.
High volume components offered by VIAVI, including low angle shift 3D sensing filters and eye-safe engineered diffusers, support cutting-edge 3D sensing processes with robust, repeatable optical solutions that enable the advancing wave of diverse 3D applications.
What is 3D Sensing?
Three-dimensional (3D) sensing is the process of obtaining depth, length, width, and featural data for objects, humans, or machines, and using this information to support a myriad of day-to-day activities. 3D sensing technology combines the scientific principles behind light reflection, geometry, and infrared photography with advanced computing power to mimic, supplant, or expand human visual capabilities.
Since initially finding a practical utilization in the home gaming industry, 3D sensing applications have expanded to include the gesture and facial recognition that enhance the security and functionality of laptop computers and mobile devices. Using 3D sensing, virtual reality (VR) or augmented reality (AR) can combine real-world 3D images with computer-generated projections to create or supplement visual experiences in unique and valuable ways. Transportation, industrial, and medical processes also benefit from the safety and efficiency gained through advanced world facing 3D sensing technology.
VIAVI leads the industry with patent-protected low angle shift (LAS) filters featuring high signal-to-noise ratios. These highly precise, proprietary 3D sensing filters provide unmatched optical performance and value with volumes approaching two billion delivered units.
Additional VIAVI 3D component offerings include high transmission light shaping optics with precise diffusion profiles that provide intrinsic eye safety through the suppression of all zero-order light.
Types of 3D Sensing
Two primary categories of 3D sensing technology are known as Time of Flight (ToF) and Structured Light (SL). Each sensing method lends itself well to multiple applications, depending on the speed, resolution, and power consumption requirements of the end user.
Direct Time of Flight
As the name suggests, Direct Time of Flight (DToF) 3D sensing employs short timed pulses of light followed by a direct measurement of the reflected light’s return time to accurately determine the position of an object. Much like ultrasound or sonar, the resolution of this method depends on the volume and speed of data capture. DToF is the primary depth sensing method for the Light Detection and Ranging (LiDAR) systems used in consumer electronics, autonomous vehicles, and other industrial applications.
Indirect Time of Flight
Indirect Time of Flight (IToF) technology uses the phase, rather than time signature, of reflected light to calculate the distance to individual points on an object. The indirect method utilizes a continuous, modulated light source at a set frequency. This enables the position to be accurately determined based on only the phase difference between incoming and outgoing light signals. IToF sensors perform best in short range conditions of 30m or less.
Structured light 3D sensing utilizes a calibrated grid or pattern of infrared light projected onto the object. A 3D sensing camera is used to detect the distortion and intensity of the pattern to ascertain the relative distance and shape of the object. Alternate structured light sensing techniques utilize phase shifted patterns or IR dots rather than a traditional square grid. A sophisticated algorithm is used to reconstruct the 3D surface topography. Structured light 3D sensing technology generally produces higher accuracy than ToF sensing with less inherent power consumption even though the underlying software is more complex.
3D Sensing Components
Complete 3D sensing systems require all components to perform harmoniously so that high resolution, accurate sensing can be realized by the end user. The illumination sources for these systems are typically laser diodes or LEDs which generate infrared (IR) or near-infrared light that is invisible to the human eye. Vertical cavity surface emitting lasers (VCSELs) are an extremely popular illumination option due to their low energy demand, compact size, and high reliability.
A native IR light source must be modulated though light shaping optics, a unique VIAVI offering, to create a field with customized irradiance and intensity suitable for 3D sensing applications. Eye safety is maintained through optics that suppress all zero-order light. Advanced engineered diffusers are capable of homogenizing input beams while shaping the output intensity profile, making them an essential ingredient for both Structured Light and ToF sensing applications.
Controlling optics, including narrow-bandpass filters with high signal-to-noise ratios, perform an essential function by preventing extraneous light from reaching the sensor. This precise filtering improves system accuracy and reduces the processing burden. The patented VIAVI low angle shift (LAS) 3D sensing filter effectively blocks out ambient light and reduces center wavelength shift in a reduced filter thickness ideally suited for many current and emerging applications.
Additional components include the depth cameras and firmware that complete the transformation of reflected light waves into meaningful 3D data sets. Cameras equipped with 3D sensors capable of rapid scanning and cloud point acquisition rates convert light source inputs into electrical energy. Customized firmware is then used to produce the digital code which can be deciphered by a myriad of cutting-edge applications. 3D sensing firmware can be upgraded as algorithms and functions continue to evolve.
3D Sensing Technology Applications
The arrival of 3D sensing as an integrated element of everyday life is perhaps best embodied in mobile handset advancements. User-facing 3D sensing significantly enhances security through facial recognition while world facing 3D sensing provides countless opportunities for augmented reality and high-performance depth sensing photography. As the demand for 3D sensing camera technology continues to envelope the mainstream, the illumination source, LAS filter, and diffuser production volumes must continue to ramp.
Biometric scanning and other cutting-edge 3D sensing technologies are redefining the world of consumer electronics. Large user interfaces for 3D graphics and applications, such as laptops and tablets, expand on the AR/VR, motion sensing, and security innovations of mobile devices, merging reality and imagination in new and innovative ways. The gesture recognition capabilities of Microsoft Kinect that revolutionized the home gaming industry now include multi-player 3D position sensing, facial expression detection, and touchless heart rate monitoring.
The automotive industry once seemed like an unlikely beneficiary of 3D sensing technology. However, autonomous vehicles and other intrinsic driver assistance features have now made 3D sensing essential for meeting transportation safety expectations. LiDAR systems have become a backbone technology for the short and long-range 3D sensing that enables vehicles to independently assess their surroundings in real time and without human intervention.
In-cabin sensing and driver monitoring supported by 3D sensing cameras can be used to warn drivers who appear inattentive or drowsy, track occupancy, and enable gesture-driven commands. Vehicles can also employ facial recognition technology for ignition locks and automatic adjustment of driver preferences, such as climate control, seat, and mirror settings.
Nimble robots operating in highly dynamic environments utilize ToF and structured light technologies to quickly identify work objects and obstacles. 3D sensing allows automated warehouse order fulfillment to be completed on a massive scale with product damage and other non-conformances detected more efficiently.
Augmented reality can be used to optimize volumetric truck and container loading patterns in much the same way a consumer might position virtual furniture in their 3D-rendered living room.
Humans, robots, and heavy machinery operating in close quarters can increase exposure to safety and security issues. Potentially sensitive environments like sawmills, power plants, and data centers use 3D sensing technology to detect unsafe conditions, recognize users based on facial characteristics, and shut down equipment or facilities to proactively avoid accidents, injuries, or unauthorized entry.
How VIAVI is Advancing the 3D Sensing Industry
Improvements to 3D sensing components and software have quickly moved ToF and structured light applications from niche markets into a broad range of consumer, industrial, and logistical applications.
Mobile device facial recognition, once conceived as a security enhancement, has now enabled user-created avatars and augmented reality using world facing 3D sensing that underscores the unlimited creative potential. At the same time, advancements in LiDAR continue to move autonomous vehicles from the drawing board to the roadway. This rapid expansion from gaming and consumer electronics into multiple industry verticals is expected to create a $6.5 billion 3D sensing market globally by 2025.
With an unparalleled track record for high volume production of patent-protected, low angle shift filters with exceptional signal-to-noise performance and high-transmission light shaping optics, including engineered diffusers, VIAVI is uniquely poised to meet the demands of the burgeoning 3D sensing ecosystem.
Since playing a pivotal role in the development of the groundbreaking Microsoft Kinect gaming console, VIAVI has maintained an unwavering commitment to innovation and cost of quality. Combined with over 70 years of industry experience, this has resulted in the advanced processes and streamlined supply chain performance that support the industry’s best 3D sensing component technology.