At Yole Développement, we have been at the forefront of microLED display analysis for years now. We have been expanding the views of the industry for this emerging technology with our most recent “MicroLED Displays – Intellectual Property Landscape and Analysis 2021“. MicroLED microdisplays are a segment of this technology. They are directly aimed at applications including augmented reality (AR) heads-up displays for automotive and what many consider to be the next consumer electronics revolution, replacing smartphones with AR headsets. We see more movement in the supply chain trying to consolidate positions. We have therefore been explaining two key ideas running in parallel for this upcoming revolution in our report “Displays and Optics for AR & VR 2020“.
First, for the revolution to happen, OEMs will need to build a strong a compelling use case that should go beyond the simple smartwatch-like near-eye display screen to convince consumers. Secondly, the different technology blocks required for an AR headset have to keep improving to meet the demanding conditions required for this adoption for brightness, efficiency, cost, volume and so on.
We believe that microLED microdisplays are bound to be enablers for this consumer electronics revolution. To that end, we saw Facebook signing an exclusive partnership with Plessey Semiconductors last year. More recently, Jade Bird Displays, one of the leading microLED microdisplay companies with products soon to be off the shelf, announced a partnership with Vuzix for AR headsets using its products.
While Yole is getting ready to release the upcoming updated report Displays and Optics for AR & VR 2021, Dr. Zine Bouhamri, Team Lead Analyst Imaging & Display at Yole Développement spent some time with Dr. Qiming Li, CEO of Jade Bird Displays, to discuss the status of microLED microdisplays and AR.
Dr. Zine Bouhamri (ZB): Please introduce yourself and Jade Bird Display (JBD)
Dr. Qiming Li (QL): I am the CEO and founder of JBD. JBD was founded in 2015 and we have been focusing on developing the smallest, brightest, and most efficient micro-display panels. With a fab established in Shanghai, China, JBD is considered as one of the leaders in microLED display technologies with its portfolio of active matrix microLED displays. For more information, visit JBD’s website, Linkedin or Twitter pages.
ZB: You mention on your website that you provide microdisplays that span the spectrum from UV to IR. Visible spectrum applications, mainly focused on AR headsets, are better known to the public and we will talk about them extensively hereafter. Can you please expand on the applications you are targeting in the UV or IR spectrum?
QL: UV microdisplay panels can be used in 3D printing, direct imaging (DI) for printed circuit board manufacturing to replace digital light projection (DLP), maskless lithography equipment and maskless wafer level packaging. IR microdisplay panels can be used in machine vision, structured illuminators for night vision systems and eye tracking for AR head mounted displays (HMDs).
ZB: Augmented Reality is your main focus. We always think about AR headsets but are you also considering the automotive sector where DLPs are being used for AR head up displays (HUDs)? What would be the main challenges to address this market compared to the general AR headset consumer market? Are you considering it?
QL: The simple HUD in an automobile is evolving with the right amount of info being delivered to the driver and passenger at the right time. The HUD in an automobile requires an imaging system with best-in-class brightness, contrast and low latency, which can be delivered by a microLED display. As more and more Internet of Things and sensing sub-systems begin to occupy the space available in a car the smaller the AR HUD will need to become. This will be the entry point for microLED displays fully qualified to relevant AEC-QXXX standards.
ZB: The AR market has been promised for many years now. Incumbent technologies, be they DLP or liquid crystal on silicon (LCoS), have been around for a long time, being mature and proving to be compatible with waveguiding technologies. What do you deliver that these technologies cannot? Are you still opening up new applications?
QL: LCoS still requires an illumination unit. Although smaller than DLP based projectors, the projector based on an LCoS is still much bulkier compared to a microLED projector. The image below shows our microLED projector, which is only about 0.35cm3 in volume, whereas the smallest known LCoS projector is approximately 3 cm3. In addition LCoS can suffer from colour break up, poor contrast and high latency.
ZB: There has been a resurgence of laser-based technologies, driven by Microsoft’s choice for a display engine in the Hololens 2. Do you think this could hinder the growth potential of microLEDs?
QL: It is difficult to realise a laser-beam scanning see-through display with a large eyebox. Hence, products like the Hololens 2 had to take the difficult approach of having two scanners to scan the image into the waveguide, which added bulk to the system and required certain compromises in image quality.
ZB: How do you position yourselves in terms of intellectual property? We see more and more effort being made towards mixing microLED and MEMS based solution, be they DLP or laser based. Are you looking into that?
QL: So far JBD has filed 230 patents regarding topics including near eye microLED display monolithic fabrication, materials, integrated circuit (IC) backplane architecture and design, packaging and pixel level optics. 80 patents have been granted so far. In the monolithic technology route or in the field of small pixels, such as 4 um pixel pitch or smaller, JBD has the strongest IP portfolio. Yes, there are ideas floating around regarding mixing microLED with DLP or LCOS. It would not be an efficient solution and would negate all the good features that can be delivered by a microLED in terms of small form factor, high pixel density – see the image showing 10,000 pixels per inch display below – efficiency, contrast ratio, latency and resilience to vibration. For example, the response times of microLEDs are in the nano-second range allowing a refresh rate faster than kHz for solving the nausea problem in AR.
ZB: Regarding your manufacturing process, as you are developing microdisplays on CMOS, are you limited by the lithographic nodes available to you? On top of that, would it be preferable to move toward a GaN-on-Si manufacturing process or do you consider that staying on sapphire is sufficient?
QL: The backplane node we need and everyone else needs, including LCOS and microLED, is only available on 12” CMOS wafers. It is dictated by the high data rate and high refresh rate that is required by the customers. 8” CMOS will not support production of consumer level AR displays. GaN-on-Si does sound cool as you can always highlight the large potential wafer size and fully deprecated wafer equipment. However, I do not think it is going to work for near eye display production. The growth temperature of InAlGaN materials reaches around 1050˚C. CMOS will not survive that temperature. One may try GaN-on-Si growth first and then a top-down CMOS process. In such a design, silicon underneath GaN pixel is not accessible. There is an unmanageable risk for materials compatibility as InAlGaN processes may contaminate the CMOS. On the other hand, 8” wafers are uncommon for compound semiconductors. But there is going to be a huge amount of waste to force 8” compound semiconductor wafer technology to work on a 12” CMOS wafer.
ZB: One of the criticisms made about microLEDs is the potential cost premium they present compared to LCoS for example. How do you position yourselves, all other things being equal, on that front? As the idea is to address the next consumer electronics revolution the price will probably be an important figure of merit for general adoption.
QL: The cost of an LED that was once $30 fell to $0.06 in 2016. With mass adoption microLED has the potential to become the most cost effective microdisplay technology, eliminating the need for other spatial light modulator microdisplay technologies to exist.
ZB: Another criticism made about microLEDs is the challenge of making a single chip red/green/blue (RGB) solution. As you are providing monochromatic solutions today? How do you plan on addressing the RGB problem. How do you expect the monochromatic solution to be adopted by the market?
QL: RGB microLED displays are in development. We have developed RGB projectors based on our monochrome displays. We believe that compared to a single panel RGB microLED display a colour-combined microLED engine will be more efficient in the near future.
ZB: Focusing on your business model and taking a step back on things, you announced in your press release with Vuzix that you would provide both optics and display engine solutions for AR headsets, in a joint manufacturing and supply agreement. Could you expand of the partnership? Also, with Plessey’s exclusive deal with Facebook, is your partnership with Vuzix an exclusive partnership or can we expect to see your display engines in other products, as you are almost the only ones on the market?
QL: We value our partnership with Vuzix as Vuzix is adopting our microLED panels for building various types of optical engines and products. At the same time, our microLED panels and customization services are readily available on the market. JBD is maintaining and will maintain a status of independent microdisplay display supplier.
ZB: Vuzix is a waveguide based AR headset company, and we at Yole think that waveguides will definitely be the way to go with AR headsets. Are you however working with OEMs that are focusing on regular birdbath optics? How do you see the future in terms of optics choices?
QL: Waveguides definitely seem to be the technology that delivers on high transparency and desirable form factor. A large eyebox and microLED microdisplay is the only viable display solution that can work with waveguides without adding bulk and retaining the larger eyebox. We are however agnostic to the optical technology. We are working across the board with partners involved with all see-through optic technologies. Any details shared here would make it obvious who they are.
ZB: Bringing your product to market, do you think that everything is ready for mass adoption of AR headsets? Is something missing? What would be the biggest challenges to convince consumers?
QL: The answer is a firm yes that it is ready for mass production and mass adoption. In the market there are early adopters and there are followers who successfully make variants and iterations of successful products. The only thing missing is competition, with our old friend Plessey unavailable. For now, JBD seems to be alone, but not lonely. JBD is racing with herself. We are enabling our partners and customers to be successful in their intended application with our technology and we are confident others will follow with their success.
ZB: When can we expect to see your next big announcement? CES 2022, hopefully face to face? Later? Where can we meet you?
QL: A face-to-face meeting at CES2022 would be nice after the world sheds covid-19. I am looking forward to it.
ZB: A final word to the readership?
QL: Stay tuned. MicroLED displays for AR are around the corner.
Dr. Qiming Li is the founder and CEO for JBD. He is an expert in III-V compound semiconductor materials and optoelectronic devices. In 2015, Qiming Li founded JBD, an integrated design and manufacture company of ultra-small display panels using micrometer or nanometer scale compound semiconductor emitter arrays as pixels. Qiming Li has a Ph.D. degree in chemical engineering. He enjoys inventing technologies and creating products, and has over 100 patents.
As a Technology & Market Analyst, Displays, Zine Bouhamri, PhD is a member of the Photonics, Sensing & Display division at Yole Développement (Yole).
Zine manages the day to day production of technology & market reports, as well as custom consulting projects. He is also deeply involved in the business development of the Displays unit activities at Yole.
Previously, Zine was in charge of numerous R&D programs at Aledia. During more than three years, he developed strong technical expertise as well as a detailed understanding of the display industry.
Zine is author and co-author of several papers and patents.
Zine Bouhamri holds an Electronics Engineering Degree from the National Polytechnic Institute of Grenoble (France), one from the Politecnico di Torino (Italy), and a Ph.D. in RF & Optoelectronics from Grenoble University (France).
Displays and Optics for AR & VR 2020
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