Light Engines for XR Smartglasses by Jonathan Waldern, Ph.D

Home , MicroLED, Smartglasses, Virtual retinal display

August 28, 2020 Light Engines for XR Smartglasses By Jonathan Waldern, Ph.D. The near-term obstacle to meeting an elegant form factor for Extended Reality1 (XR) glasses is the size of the light engine2 that projects an image into the waveguide, providing a daylight-bright, wide field-of-view mobile display

For original equipment manufacturers (OEMs) developing XR smartglasses that employ diffractive waveguide lenses, there are several light engine architectures contending for the throne. Highly transmissive daylight-bright glasses demanded by early adopting customers translate to a level of display efficiency, 2k-by-2k and up resolution plus high contrast, simply do not exist today in the required less than ~2cc (cubic centimeter) package size.

This thought piece examines both Laser and LED contenders. It becomes clear that even if MicroLED (µLED) solutions do actually emerge as forecast in the next five years, fundamentally, diffractive waveguides are not ideally paired to broadband LED illumination and so only laser based light engines, are the realistic option over the next 5+ years.

Bottom Line Up Front

• µLED, a new emissive panel technology causing considerable excitement in the XR community, does dispense with some bulky refractive illumination optics and beam splitters, but still requires a bulky projection lens. Yet an even greater fundamental problem of µLEDs is that while bright compared with OLED, the technology falls short of the maximum & focused brightness needed for diffractive and holographic waveguides due to the fundamental inefficiencies of LED divergence. • A laser diode (LD) based light engine has a pencil like beam of light which permits higher efficiency at a higher F#. This in turn results in a much improved Liquid Crystal on Silicon (LCoS) microdisplay panel contrast when compared with traditional LED LCoS designs. • Looking to the future and miniaturizing still further, the projection lens itself may be integrated into the waveguide using diffractive metasurfaces containing sub-wavelength structures or “metalenses,” which are better suited to laser illumination compared to LED illumination. • By leveraging the benefits of lasers and its holographic switchable optics platform, DigiLens is using its extensive experience with diffractive optical waveguides to create a new class of light engines referred to as Waveguide Integrated Laser Display (WILD). The WILD category of light engines offer OEMs more immediate time to market and is a lower-risk alternative to µLED based light engines. • Laser coherence and phase also provide added efficiency gains in holographic thin film waveguides.

1 Extended Reality (XR) is a term that encompasses Augmented Reality (AR), Mixed Reality (MR), and Virtual Reality (VR) 2 Also referred to as a Picture Generation Unit or “PGU” © 2020 DIGILENS INC. | ALL RIGHTS RESERVED | TWITTER: @DIGILENSINC The Need for a Compact Light Engine for XR Glasses

Delivering a wide field-of-view (FoV), color, daylight-bright device in a spectacle-like form factor at an acceptable price continues to prove to be a major development hurdle for consumer XR displays. The form factor challenge is only par- tially met using thin diffractive and holographic waveguides. Current light engines comprising of the microdisplay beam splitter and projection DigiLens’ Visualize Design v1 lens are increasingly seen as too bulky to satisfy the aesthetic requirements of glasses. speckle and other illumination non-uniformities.

In addition, misunderstanding also prevails with Let’s dig deeper into the leading light engine respect to outdoor contrast requirements which options on the market today illuminated by ei- has an oversized impact on brightness and bat- ther Light Emitting Diodes (LED) or Laser Diode tery life. Here, ambient light can wash out the (LD). content and render the image unrecognizable. Under generally accepted guidelines, an Am- LIGHT EMITTING DIODES bient Contrast Ratio (ACR) of 3:1 is required for recognizable images, 5:1 for adequate readabil- µLEDs Engines ity, and 10:1 for appealing quality.3 µLED is a thin emissive panel technology that Given a 90% transparent waveguide and in- dispenses with beam splitting and illumination door office lighting condition (150nits), the XR optics, thereby offering higher brightness and display target luminance level should have at much smaller size. There is consequently great least 550nits for ACR 5:1 – which is considerably interest in this technology. Yole, a leading indus- less brightness than that required to overcome try analyst, believes that µLED technology could outdoor lighting condition of 300-3000nits (so match or exceed OLEDs for most key display 4 2-20x). It is notable that the HoloLens 2 display attributes, especially brightness and efficiency. is 1000nits and that all current XR displays use However, as Yole points out, there is no sign of a sunshades, which longterm are unwelcome for color µLED light engine for XR applications. The consumers. Ultimately, even assuming a dan- reasons for this can be attributed to both basic gerously darkened room, the waveguide display device physics and technological obstacles to contrast is likely perfectly acceptable at 30-40:1, achieving process maturity. so well short of and not to be confused with the LCD, µLED or µOLED native display panel con- As µLEDs get small enough to satisfy the trast, irrelevant for an XR display application. 2k-by-2k resolution ideal for XR, the pixels suffer from surface recombination, etching- The low etendue and the narrow band of laser related defects on the side walls of the chip, emitters makes them the ideal choice for deliv- current crowding, and other thermal effects ering excellent color gamut and high brightness which all impact the external quantum effi- with high transmissivity that can meet the large ciency. number of outdoor use cases requiring compact form factors. However, laser emitters have tradi- Driving the LED pixels in the panel brighter to tionally brought new problems including laser overcome low efficiency is limited by higher

3 Dobrowolski J A, Sullivan B T, Bajcar R C. Optical interference, contrast-enhanced electroluminescent device. Applied, Optics, 1992, 31(28): 5988–5996 DOI:10.1364/AO.31.005988; and Chen H, Tan G, Wu S T. Ambient contrast ratio of LCDs and OLED displays. Optics Express, 2017, 25(26): 33643–33656 4 µLED Displays 2018, Yole Development, July 2018

© 2020 DIGILENS INC. | ALL RIGHTS RESERVED | TWITTER: @DIGILENSINC PAGE 2 power consumption, current drop and heat dis- MOCVD reactor suppliers also have credible sipation requirements. Solutions to the efficiency roadmaps to deliver cost-effective tooling. De- problem have been identified (e.g. thermal an- spite these advances, there are still significant nealing, side wall passivation and improvements challenges to developing a consumer µLED to LED structures and materials). Reducing the based light engine to match diffractive wave- sheet resistance of the current-spreading layer guide requirements. of the µLED chip has also been shown to give a uniform current distribution and alleviate current Current Commercial Activity and Status of crowding. µLED Displays

Another effect that appears as the pixel size is In recent years the market has seen significant reduced, is a gradual increase in the light emis- µLED business development, with Facebook sion through the side wall leading to a far field (Oculus) taking a lead by acquiring two Univer- deviation from the normal Lambertian character- sity spinoffs: Irish µLED developer InfiLED (2016) istic of the µLED. This side emission depends on and a UK company mLED (2017). Apple is also the semiconductor material index and the de- reportedly considering investing a further $330 vice structure, but can certainly be a problem in million into a Taiwanese factory to manufacture color displays as different materials are used for both LED and µLED displays for future iPhones, different colors. The combined side emissions iPads, MacBooks, and other devices, so µLED can lead to an angular color shift that can also display technology must be seen in the context distort the color balance of the final image, re- as being enabling to a broad range of display sulting in a subpar experience for enterprise and product categories. consumer use cases. Additionally, Facebook has demonstrated a green (520 nm) nHD (640x360) µLED array with 6-micron pixels on a 20-micron pitch.6 Pixel sizes down to 2-4 microns may be in the cards. Improvements to circuit complexity, efficiency drop at low pixel sizes and wall plug efficiency resulting from reduced specific contact resistivity (<10-4 ohm/cm2) and sheet resistance of ~100k Plessey and Compound Photonics’ ohms square are also claimed. 0.26”diagonal display module Facebook and Plessey Efficiency is not the only challenge for µLEDs. An integration technology for active matrix driving, A partnership between Facebook and Plessey technologies for full-color realization, and defec- announced in March 2020 will leverage Plessey’s tive pixel control all still remain major develop- LED manufacturing expertise to help Facebook ment hurdles. Driving µLEDs is more complex prototype and develop new technologies. than OLEDs and using standard low tempera- ture polysilicon or oxide TFT backplanes might Plessey is increasing investment in their fab to not be as straightforward as expected. Full color improve volume and yield. It is notable that with also requires integration of phosphors or QDs to Oculus, Facebook can use µLED panels in both the µLEDs, a process that is in its infancy. VR headsets and AR transparent glasses, so they are likely taking a long term view into several On a positive note, Yole reports that leaders are sub-categories of XR displays, both handheld achieving 99% yields, and small die efficiency and head mounted, with VR likely being earlier is approaching or exceeding that of OLEDs.5 to market.

5 µLED Displays 2018, Yole Development, July 2018 6 www.mled-ltd.com

© 2020 DIGILENS INC. | ALL RIGHTS RESERVED | TWITTER: @DIGILENSINC PAGE 3 Earlier this year, Compound Photonics and As shown in the specifications below, the blue Plessey Semiconductors Ltd announced the output is significantly less than green, even ac- first fully addressable µLED XR display- mod counting for the human visual efficacy differ- ules resulting from a partnership to develop ence. Also, our understanding is that the red GaN-on-Silicon µLED displays for XR. Other sig- material set is even more of a challenge. Jade nificant movements by Plessey in 2020 included Bird is working to remedy the fundamental de- a partnership with Axus Technology, a leading vice physics and manufacturing issues as part of global provider of semiconductor processes, to their roadmap, but no production date as been commercialize high-performance GaN-on-Sili- announced yet. con monolithic µLED technology and another partnership with WaveOptics to develop next generation smartglasses.

µLED brightness falls dramatically as size reduces

Ostendo Oculus Concept for a waveguide-based VR headset Image courtesy Facebook

Jade Bird The Southern California based company Os- tendo is marketing a different µLED approach called RGB QPI®, that’s also receiving a lot of attention. The company’s patents describe the QPI as a “…3D-IC semiconductor device comprising a high density array of digitally addressable micro-LED pixels,” with its simultaneous color emission, so the RGB pixels share the same optical aperture per pixel but with a constrained Monochrome (green only) Jade Bird waveguide eyepiece emission profile.7 The Shanghai based company Jade Bird is cur- It is highly unlikely the LED emission physics rently sampling µLED panels delivering 3M nits are fundamentally different to other µLED de- at 530 nm and 150k nits at 455 nm with contrast vices, so the Ostendo QPI® offering will likely at 10,000:1, pixel sizes down to 2.5 micron and still suffer from the same luminance shortfall for 360Hz refresh rate. Of course bichromatic and waveguide based eyeglass solutions. Ostendo trichromatic versions are in development. The is reported to be making its own eyeglass optic arrays use refractive micro-lens arrays, bonded so perhaps lessening the requirement of a dif- onto the µLED array for beam shaping to im- fractive waveguide design, currently proferred prove efficiency. by OEM’s.

7 El-Ghoroury, H. (2014/ December 4). “Quantum Photonic Imager (QPI): A New Display Technology and Its Applications“.

© 2020 DIGILENS INC. | ALL RIGHTS RESERVED | TWITTER: @DIGILENSINC PAGE 4 Apple, Facebook, Plessey, Jade Bird and Os- and modulation speed that is impossible for a tendo are not the only lively players in the µLED single RGB LBS light engine design. A tiled laser field. Yole points out that Samsung AOU, Inno- fiber virtual retinal display (VRD) advocated by lux and LG are all very active,8 with Samsung pur- Magic Leap is theoretically possible11, but ulti- suing three separate architectural efforts (one in mately too complex and costly as it would need particular: its QNED nanorod “ink” which could an array of tiled diodes and drivers to achieve be a major disruption). the modulation bandwidth.

According to Yole, it appears Apple leads the Other arguments in favor of scanned laser for XR µLED race when factoring in the Luxvue acquisi- is that they are always in focus and hence solves tion and internal developments. Yole anticipates the vergence-accommodation conflict (VAC), a 30% µLED based XR penetration by 2027 and however new Maxwellian VRD architectures12 they highlight that several start-ups have already which use Liquid Crystal on Silicon (LCoS) spa- collectively raised close to $0.8B and are likely tial light modulators are also always in focus, so to add another $100M in 2020. It should also be common to all laser based light engine architec- noted that these dollar amounts exclude the tures and a critically important feature for XR ap- new Apple $300M investment rumors. plications.

LASER DIODES

Laser Based Scanning (LBS) Engines

Two notable head mounted displays have both developed laser diode driven LBS systems. One has been implemented in the HoloLens 2 (HL2) and the other in the North9 Focals smartglasses. However, there remain fundamental challenges10 to sufficiently scale either of these solutions for The North Focals provide a good example of an LBS niche the future high resolutions required for wide FoV as XR content is sparse XR, especially the vertical FoV, which is lacking in the HL2. For low-resolution consumer market applications implementing “watch type” notification Put simply, the limitation for future LBS XR is companion displays, like the North Focals, LBS the laser pixel modulation requirement to pulse can fit that niche, although the small eyebox in modulate (PWM) the brightness for each pix- these non-waveguide displays will likely always el location. These physics are almost saturated limit consumer enthusiasm. This is especially today with 16:9 aspect ratio in HL2’s 2048x1080 the case where XR content is sparse, but it must resolution. The limit is with the laser driver chip. be noted that users have expressed skepticism for that use case at scale.13 As waveguide FoVs increase from 52° today to a more immersive 70° or 90° this decade (in both Whilst LBS based light engines come with horizontal and vertical axis), the 2k-by-2k going the benefit of small volumetric packaging, to 4k-by-4k resolution will demand a scanning efficiency and high brightness, their role

8 µLED Displays 2018, Yole Development, July 2018 9 Purchased by Google – https://www.bynorth.com 10 Detailed tradeoff analysis by Karl Guttag at https://www.kguttag.com 11 US20150268415A1 Ultra-high resolution scanning fiber display – Magic Leap 12 Accommodation-Free Head Mounted Display with Comfortable 3D Perception and an Enlarged Eye-box https://doi. org/10.34133/2019/9273723 13 For example the lack of sales for GoogleGlass and Vuzix devices, and even push back on special notifications with the Echo Frames described in detail here: https://www.washingtonpost.com/technology/2020/08/04/echo-frames-review/

© 2020 DIGILENS INC. | ALL RIGHTS RESERVED | TWITTER: @DIGILENSINC PAGE 5 in XR is likely diminished due to resolution homogenization, beam shaping, beam splitting limitations, scanning uniformity, mechanical and high contrast image projection from an reliability and safety. It is likely the niche for LCoS, but in a breakthrough tiny package. This LBS will be limited to low resolution, simple alternative approach to µLED leverages Dig- notification smartglasses. iLens’ electrically switchable diffractive waveguide optics to achieve high brightness, contrast Laser Illuminated Liquid Crystal on Silicon and color gamut, whilst overcoming speckle. (LCoS) Light Engines The WILD light engine contains a tiny array of For the last 20 years, LCoS has been a poor sec- switchable diffuser pixels in the light path, which ond to DLP based light engines, despite LCoS are patterned and switched rapidly to gener- panels having a distinct cost advantage and the ate a multiplicity of different speckle patterns, critical smaller pixel size needed for high resolu- which in turn eliminates laser speckle from the tion small aperture size. As LED light has a wide projected image into the combiner waveguide. cone to collect a sufficiency of light, as this light The fundamental methodology and architecture cone is mirrored to reflect off the LCoS panel, is a breakthrough feature of WILD and will be overall image contrast suffers. Liquid Crystal (LC) covered more fully in a forthcoming light engine panels cannot modulate light (light to dark) at a article. WILD opens the door for Laser diodes high angle. to directly compete and surpass in many cases there µLED counterparts. Additionally, LED light is unpolarized and like all LC displays, only polarized light can be used. DLP Later this year, initial demos of WILD will be with LED always wins as they both use mirrors, showcased in a ~3cc package with a develop- so they have high contrast with high illumination ment pathway to ~1cc total light engine size (di- angles and are not polarization dependent, so it odes, imaging waveguides, panel and coupling can use all the LED light. When compared with lens). LCoS panels already have a mature supply LCoS, DLP with LED is twice as bright and effi- chain with multiple manufacturers, 2k-by-2k, with cient. Lasers are a perfect marriage with LCoS, 3µm pixel panels and are available now. They as laser light is polarized and thus all the light also have a clear path to 1.5μm pixels for a near can be collected and shaped onto the LCoS term 3k-by-3k tiny package. As such, WILD offers panel with a low angle, giving very high contrast. a lower-risk and overall superior performance solution for OEMs developing XR solutions start- So why do we not see more Laser/LCoS light en- ing in 2021. gines for XR? The problem has previously been that the use of laser illumination comes with an unwelcome artifact: Speckle.

Easily recognizable as a sparkly or granular structure around uniformly illuminated rough surfac- es, speckle arises from the high spatial and tem- poral coherence of lasers. The resulting viewer distraction and loss of image sharpness has Notional WILD pico-projector module been a major obstacle to commercialization of laser Illuminated light engines. Additional Design Evolution Benefits

However, in a feat of optical origami, DigiLens Given WILD has used diffractive waveguides to has created a highly innovative Waveguide Inte- integrate optical functionalities, even the projec- grated Laser Display (WILD) light engine which tion lens may benefit from advanced techniques uses waveguide optics to integrate despeckling, to eliminate bulky refractive optics. In the current

© 2020 DIGILENS INC. | ALL RIGHTS RESERVED | TWITTER: @DIGILENSINC PAGE 6 WILD reference design, a miniature projection Metalens designs currently being reviewed also lens employs a five (5) lens element, and 15mm provide a collimator and display waveguide projection lens module. Moving to a “pure” all in-coupler. Metalenses can also assist with la- diffractive WILD design, whilst capitalizing on ser aberration correction, color correction and the WILD londitudnal form factor, it is now con- beam shaping. ceivable to integrate even the projection lens into an even smaller volume. Narrow band laser DigiLens’ analysis suggests that metalenses are illumination is key to enabling diffractive optics highly promising candidates for a thin flat lens technology and thus a time to market enabler. that can encode all the optical functionality of a multi-element projection lens, significantly re- Metalenses ducing WILD’s overall volume by half to below 1cc. Laser illumination also allows the use of Metalenses are a recent addition to the diffrac- metalenses to be developed to complement tive optics family, where the nanoscale optical DigiLens’ flat holographically recorded lenses, structures used in metalenses can allow more already proven in DigiLens’ AutoHUD. So broad- subtle control of polarization, phase and am- band μLED therefore leaves OEMs at a disad- plitude down to the diffraction limit. The most vantage, as they are unable to harness the next significant feature in terms of imaging is the use step in diffractive miniaturization. of surface features including height which is typically ~ 500 nm, combined with at least one other APPLES TO APPLES – dimension <<λ, (typically ~10s of nm). DAYLIGHT BRIGHTNESS, XR LIGHT ENGINE REQUIREMENTS A recent example developed by Metalenz (a Harvard spin-off) uses complex patterns of titani- WILD vs. µLED um oxide nanofins on a glass substrate. The lens eliminates chromatic aberration over the visible A theoretical comparison was made of a full band by optimizing the shape, width, distance, color WILD based XR smartglass display vs. an and height of the nanofins, where a single mask equivalent µLED powered version, given a dis- semiconductor production process is used for play specification of 5,000 nits; 30° diagonal FoV, fabrication. 12x10mm eyebox, assuming a waveguide efficiency of 1%, and from a laser illuminated LCoS (8.4x5.93 mm) to match the same aperture as the Jade Bird µLED panel previously referenced. Us- ing identical F-numbers and losses, our model predicts the RGB µLED panel luminance needed to hit the display specification would be approx- imately 300k/nits, 750k/nits and 60k/nits respec- tively, or 1.1M/nits at D65 color point.

Individual R and B µLED panels are currently a fraction of this brightness and when mounted around a dichroic beam cube, are too bulky. As mentioned earlier, there’s no sign of a trichromatic µLED panel with the required RGB effi- Full color Metalens Research published in cacy. This together with the diversity of device “Nature Nanotechnology” (doi:10.1038/s41565-017-0034-6) technologies needed for RGB, fundamental physics-related device efficiency problems, and electronics integration challenges, leaves µLED at a significant disadvantage relative to WILD.

Parameters WILD µLED Crystal30 Waveguide Lens Crystal30 Waveguide Lens Equivalent

Architecture

Luminance at 5,260 nits D65 5,260 nits D65 Eyebox 16:9, 30º diagonal FoV 16:9, 30º diagonal FoV Specification Eyebox: 12mm x 10mm Eyebox: 12mm x 10mm 100% Beam Shaping 42% Efficiency Emissive technology 67.5% 100% Panel Efficiency LCoS efficiency Emissive technology 90% 90% Lens Efficiency Etendue matched to FoV at eyebox F/2.7

Waveguide 1% 1% Efficiency R G B

Lumens out of 7.48 2.1 5.0 0.4 Lens Panel Lumi- N/A 3.1 x 105 7.5 x 105 5.9 x 104 nance (nits) µLED panel size: 8.4mm x 5.93mm

Also, while such high luminance values have gines, have been commercially available from a been demonstrated for monochrome µLED de- range of licensed manufacturers for over twenty vices having larger pixel size, that has not been years. The leading 0.2” WVGA miniature light the case for the tiny 2-3um pixel size needed for engine is used in the DigiLens smartglasses XR glasses. which ergonomically performs well for its resolution specification. One obvious solution to compensate for the lack of µLED brightness is simply to increase wave- Fundamentally it is unlikely this or any DLP light guide efficiency. Yet this would entail an order of engine will serve XR light engine requirements, magnitude increase, which is not feasible in the given the LED size and thermal limitations com- short term. Even if one could make an efficient pounded with DLP chip size inherent to the rel- RGB µLED panel, there is no short term (next 3-5 atively large MEMS pixel size. When compared years) match with µLED panel capability needed to the benefits of WILD, DLP based engines are for an daylight use XR eyeglass display. unable to deliver the high resolution and small form factor XR light engine requirement. What About DLP?

Another MEMS microdisplay that can withstand both high LED or LD flux is DLP, who’s light en-

By leveraging the benefits of laser illumination and diffractive/holographic switchable optics, DigiLens is bringing a range of laser diode based light engines to market as an alternative to LED and µLED based light engines with an equally dramatic form factor reduction.

Once integrated in industrial HUDs and lightweight smartglasses, the benefit of narrow band laser combined with LCoS, is high polarized efficiency and contrast. The benefit of laser diode combined with diffractive optics in both the light engine and waveguide eyeglass, is high efficiency, improved col- or uniformity, planar construction, miniature size and low cost. Finally, the benefit of laser combined with meta projection lens solutions, are faster time to market, as use of narrow band laser line, leads to a simpler smaller design that is more efficient.

Companies looking to build smartglasses and other forms of HUDs should be conscious of making the correct near and long-term choice about which light engine technology will scale and grow with their future generations of products. Otherwise they risk misallocating a significant amount of precious resources and will ultimately delay their XR product(s) time to market.

On behalf of the team at DigiLens, I offer this thought piece to posit that for OEMs, a WILD based light engine solution offers the most optimal path to realize a low cost, high resolution/efficiency miniature light engine and thereby maximize the likelihood of success in the emerging XR head worn category, over the next decade.

Additional References

• Clarke, P. (2020, April 2). eeNews Europe: Facebook, not Apple, gets Plessey’s microLEDs. https://www.eenewseurope.com/news/facebook-not-apple-gets-plesseys-microleds • Plessey Press Release. (2020, March 30). microLED display developer to work with Facebook. https://plesseysemiconductors.com/µLED-display-developer-to-work-with-facebook/ • Plessey Press Release. (2020, February 12). Compound Photonics and Plessey Light Up First 0.26 Inch Fully Addressable Integrated microLED Display Module for AR/MR. https://plesseysemiconductors.com/compound-photonics-plessey-first-microled-display-module/ • Plessey Press Release. (2020, February 6). Plessey partners with Axus Technology to deliver its world-leading monolithic microLED displays. https://plesseysemiconductors.com/plessey-partners-with-axus-technology/ • Plessey Press Release. (2020, February 5). Plessey and WaveOptics Announce Strategic Partner- ship Using MicroLED Display Technology for Smart Glasses. https://plesseysemiconductors.com/plessey-waveoptics-partnership/ • Peakin, W. (2017, March 7). Facebook VR firm buys Strathclyde University spin-out. https://futurescot.com/facebook-vr-firm-buys-strathclyde-university-spin/ • Lin, J. (2016, October 17). Oculus Acquires Micro-LED Company InfiniLED. https://www.ledinside.com/news/2016/10/oculus_acquires_micro_led_company_infiniled • Whiterow, P. (2016, August 2). Braveheart to book £285,000 profit on LED Co.sale. https://www.proactiveinvestors.co.uk/companies/news/128910/braveheart-to-book-285000-profit- on-led-cosale-128910.html

This thought piece expresses the views of the author(s) as of the date indicated and such views are subject to change without notice. DigiLens has no duty or obligation to update the information contained herein. Further, DigiLens makes no representation, and it should not be assumed, that the head worn hardware market will develop in a manner envisioned by DigiLens.

This thought piece is being made available for educational purposes only and should not be used for any other purpose. The information contained herein does not constitute and should not be construed as an offering of advisory services. Certain information contained herein con- cerning trends and performance is based on or derived from information provided by indepen- dent third-party sources. Digilens, Inc. (“DigiLens”) believes that the sources from which such information has been obtained are reliable; however, it cannot guarantee the accuracy of such information and has not independently verified the accuracy or completeness of such information or the assumptions on which such information is based.