Behind the first infrared transparent windshield for LiDARs

Live demonstrations of AGC windshield technology from its Wideye™ task force at CES 2019 have helped change the industry’s perceptions of LiDAR.

Combined with Velodyne’s Velarray™ sensor for an interactive demo in Velodyne’s booth, Wideye™’s infrared transparent automotive-grade glass provided a solution to manufacturers and users of ADAS (advanced driver assistance system) featuring both seamless design and safer perception.

Automotive Industries (AI) asked Tadashi Murano, General Manager of Mobility Development Office from AGC Automotive Company, and Jean-Marc Meunier, CEO of AGC Glass Europe, to give us the background into the development. Murano: The Tokyo-based AGC Group is a world-leading supplier of flat, automotive and display glass, chemicals and other high-tech materials and components. In automotive glass, it specializes in production of windows (OEM and replacement) and interior glass for vehicle manufacturers. It also provides ready-to-assemble systems (fixation devices), higher value-added functional systems (antennas, sensors, heating elements) and enhanced property glazing (improved thermal, sound and vision comfort). The AGC Group employs some 50,000 people worldwide and generates annual sales of around US$13.7 billion through business in about 30 countries. With the advent of autonomous vehicles and the need to extend sensor technologies, including LiDAR, AGC has created a specific task force, Wideye™, which is fully dedicated to developing (disruptive) solutions for these vehicles.

AI: What were the assumptions behind the development of the application? Murano: The Wideye™ task force is convinced that LiDAR will be the key enabler for autonomous vehicles. Combined with other sensors it is able to provide optimal safety to drivers. Both safety and design are the main issues for autonomous vehicles adoption. Based on its strong glass expertise, Wideye™ believes that glass is the ideal material to meet the safety and design requirements from all actors in the sector: LiDAR manufacturers, OEMs and Tier 1s.

AI: Why is glass the safest option for LiDAR? Murano: Glass provides LiDAR with a strong protection to dust and dirt. Unlike other transparent materials, glass boasts a high light transmission and is durable: it is highly resistant to scratching, impact, ageing, chemicals, color distortion by UV radiation, etc. Furthermore, glass easily lends itself to different treatments such as heating (for de-icing/ defrosting), hydrophobic coating (for evacuating water droplets), etc. Finally, glass is to be found in the upper part of the vehicle (windshield, back and sidelites, sunroofs), all around it. It occupies the ideal places to position LiDAR, providing it with the safest unobstructed views. LiDAR can then truly play the role of human eyes. All these factors may contribute to ensuring and preserving the cleanest and safest visibility to LiDAR.

AI: And what about glass and design? Murano: Wherever LiDAR can be fitted glass can serve as a protection cover since it can be processed (colors, shapes, thickness, reflection, etc.) so as to integrate seamlessly into the vehicle’s body. Designers can get rid of unaesthetic LiDAR sensors that stick out of the vehicle’s body.

AI: With so many advantages, why has glass not been adopted earlier as a solution to accommodate LiDAR? Meunier: The only drawback to standard automotive glass, especially the windshield, is that it blocks near infra-red radiation [see article XenomatiX on p. 14], invisible to the eye, to reduce heat inside the vehicle and ensure passenger comfort. However, LiDARs operate at near infrared light frequency. Wideye™ has overcome this obstacle by developing the Wideye™ glass for the first-ever infrared transparent windshield. This IR transparent glass was initially developed for very large touchscreen panels in which glass had to be transversally crossed by infrared light and for which very high infrared transmission qualities were required. This breakthrough made it possible to fit the LiDAR unit behind the windshield and to benefit from the wiped area, the unobstructed view and all the advantages provided by using glass as a protector.

AI: To what extent have you been able to demonstrate the validity of your solution? Meunier: Together with the world leader in LiDAR sensors, Velodyne, AGC showcased this windshield-mounted Lidar at CES in 2018 and 2019. It also partnered with LiDAR technology providers such as XenomatiX (see p. 14), Ouster and other actors of this industry to promote this integrated solution in which those LiDAR manufacturers strongly believe. As evidenced by the variety of partnerships, this solution is device-agnostic: whatever the LiDAR technology, it fits with our glass solution.

AI: What prospects does this breakthrough open? Meunier: Thanks to this IR transparent glass, Lidar no longer needs to be mounted externally. It also means that with this proven technology, LiDAR sensors can be located all around the car and benefit from the same advantages that glass windshield offers: in glass trims, side and backlites, sunroofs and any other place fitted with a glass cover. It is an important step forward on the way of ADAS applications and self-driving cars.

AI: How can Wideye™ assist with the integration of LiDAR in vehicles? Meunier: Wideye™ expertise and contribution can develop at three levels: Design We can help our customers (LiDAR supplier, Tier 1 or OEM) to (co)design their solutions for the use of LiDAR, by appraising the concept while meeting the optical, mechanical and aesthetic requirements. This approach includes simulation based on an advanced realistic rendering tool, prototyping and sampling, design validation and testing, industrialization. For all this, we can rely on our proven expertise as glass supplier (Tier 1) to demanding OEMs for which we do not only provide high valueadded multifunctional glass but also ready-to-assemble modules. Glass hardware We can provide customers (LiDAR supplier, Tier 1) with glass hardware (IR transparent glass and fixation devices) for industrial scale up, from the largest to the smallest part (windshield, LiDAR covers, glass trims, etc.) Global LiDAR integration with partners Based on AGC experience as a glazing Tier 1, Wideye™ aims at being a global LiDAR integrator through appropriate partnerships and providing the “eyes of the autonomous vehicle” in end-to-end managed projects. We are also open to support the development of some promising players in this field, as we have already done – as long as we believe in the same solution of glass-covered sensors.

AI: What are the next steps for Wideye™? Meunier: We want first to capitalize on the generation of windshields presented at CES 2019. We will pursue our programs of LiDAR-mounted windshields with partners, while leveraging the numerous technical breakthroughs to come in this field. The market urgency also pushes Wideye™ to launch glass cover products in the short term, based on the recognized value of functional glass by automotive actors. Bringing the best of optics to the automotive world is a must for actors willing that the sensor technology should meet harsh automotive standards. 360° integration of LiDARs will lead Wideye™ to demonstrate its extensive integration ability through additional prototypes. Let’s keep our eyes (Wide) open!