The development of AR technology has accelerated significantly during the past decade, with waveguide displays emerging as a key enabler of lightweight, high-performance AR glasses. As the CEO of Cellid, I had the opportunity to discuss the intricacies of waveguide design and its potential at SPIE Photonics West 2025. This article provides an overview of our waveguide technology, the challenges we faced in its development, the materials we use, and the exciting future it enables.
Role of waveguides within AR glasses
Waveguides form the optical backbone of modern AR displays, allowing images to be projected into the user’s field of view (FOV) while maintaining a compact and lightweight form factor—essential for prolonged wearability and user comfort. Unlike traditional AR/mixed reality (MR) displays that require bulky external components, waveguides guide light within the lens itself, which eliminates the need for additional reflective mirrors or optical structures. This enables AR glasses to maintain the same thinness and weight as ordinary eyeglasses, which makes them suitable for all-day wear without appearing unusual to others.
There are three types of optical see-through display systems used in AR/MR technology, and our company has implemented the waveguide method. The introduction of waveguides, which can be designed to resemble ordinary glasses, marked a significant breakthrough within the field. As a result, commercialization is rapidly advancing among device manufacturers, including big tech companies.
Figure 1 illustrates how waveguides function: Light from a microprojector enters the lens and propagates through total internal reflection, precisely directing it to the user’s pupil. This process leverages nanotechnology from the semiconductor field to achieve fine-tuned light adjustments and optimal image clarity. Waveguide technology also uses 2D expansion via unique grating structures to enhance the uniformity and efficiency of the display. Various optical coatings further refine image quality by reducing ghosting, color inconsistencies, and brightness variations.
Companies need to innovate beyond general waveguide technology. For instance, Cellid developed proprietary innovations—including a fully laminated layer structure with no air gap, which eliminates the need for protective covers, and a wide 70° FOV—enabled by an inhouse simulator, unique materials, and specialized production processes (see Fig. 2).
By leveraging waveguide technology, AR glasses can achieve a sleek, everyday-eyeglass appearance and light weight, while maintaining high performance—unlike bulky headsets or oddly shaped AR devices that are impractical for daily wear.
This is possible because waveguide displays require only a microprojector and the waveguide lens to function—eliminating the need for bulky optics or external display components. By integrating the optical path directly into the lens, the waveguide enables a compact and lightweight design, and AR glasses match the shape and weight of regular eyewear. As a result, users can wear them comfortably throughout the day without drawing attention, unlike oversized headsets or oddly shaped AR devices that feel out of place in everyday settings.
Our waveguide technology can be broadly categorized into diffractive and reflective types. In both approaches, light from a microprojector is directed to the user’s eye using the principle of total internal reflection. This method allows for precise control of light paths while maintaining a minimal physical footprint.
By leveraging nanotechnology commonly used in semiconductor manufacturing, our waveguides can finely manipulate light within the lens itself to achieve high visual clarity and brightness within a compact form factor. Unlike traditional optical systems that rely on bulky mirrors or external display elements, waveguide-based AR displays require only a lens and microprojector. This simplicity enables AR glasses to closely resemble ordinary eyewear in both shape and weight, which makes them far more practical and socially acceptable for everyday use.
At Cellid, we’ve focused on maximizing the efficiency of our waveguide designs to improve brightness, resolution, and FOV, while also minimizing size and weight. Our proprietary waveguide technology, including the Cellid Waveguide 70°, achieves a balance between compactness and high optical performance to deliver an optimal user experience for AR applications.
Designing an optimal waveguide
Waveguide design requires a deep understanding of optics, materials science, and manufacturing processes. A well-designed waveguide should ensure efficient light transmission, minimal distortion, and high contrast. The key components of a waveguide include: Optical design technology (nano-design + layer architecture design).
Our work began designing waveguides using existing simulation tools. Typically, there is a tradeoff between brightness and modulation transfer function (MTF)—particularly when using slanted or blazed diffraction patterns. We believed this challenge could be addressed by optimizing multiple organic materials on a binary basis. But we found that existing tools were insufficient for accurately modeling the complex behavior of organic materials like coatings and resins. To overcome this limitation, we developed a proprietary inhouse simulator capable of optimizing a wide range of material conditions to maximize waveguide performance. In addition, while conventional waveguides require an air layer and a cover glass, we independently developed a fully laminated structure that eliminates both—and significantly reduces the overall weight and thickness of the lens.
Materials and process technologies
We are continuously developing advanced materials in collaboration with partners—materials that not only meet the performance requirements defined by our simulations but also offer durability to withstand impact, temperature variations, and other environmental stresses over time.
To bring our unique and intricate designs to life, we have established a robust manufacturing ecosystem in partnership with leading companies from the semiconductor and related industries. This collaboration enables the precise production of our advanced optical systems at scale.
Materials and manufacturing challenges
One of the primary challenges in waveguide development is selecting the right materials (see Fig. 3). The ideal material must be highly transparent, have precise refractive index properties, and be manufacturable at scale with high consistency. Key considerations include:
Glass vs. polymer substrates. Glass provides superior optical clarity and durability and can also be manufactured at scale. But compared to polymers, glass has some weaknesses, including higher cost and lower impact resistance. Polymers, on the other hand, are lightweight and more flexible but often suffer from birefringence (double refraction) and durability issues.
Refractive index matching. Ensuring uniformity across the waveguide is critical for maintaining image clarity. Any inconsistencies can lead to visual distortions.
Surface quality and coatings. High-quality antireflective coatings and precise surface treatments are necessary to minimize losses and unwanted reflections.
At Cellid, we invest heavily in developing proprietary materials and coatings that balance optical performance with manufacturability. Our next-generation waveguides are designed to be thinner, lighter, and more efficient to reduce the power demands on AR glasses while improving overall usability.
Overcoming key technical challenges
Despite the impressive progress in waveguide technology, several technical hurdles remain. These include:
FOV limitations. Expanding the FOV without increasing size or weight is a major challenge. Our research focuses on novel waveguide geometries and improved in-coupling methods to push beyond the current limits.
Color uniformity and efficiency. Maintaining high brightness while ensuring uniform color reproduction requires sophisticated optical coatings and advanced design algorithms.
Mass production and yield rates. Scaling up manufacturing while maintaining precision is complex. We are developing automated processes and machine-learning-driven quality-control systems to improve yield rates.
Waveguide performance and key technologies
Waveguide performance is primarily determined by three core factors: Optical design technology (nano-design + layer architecture design).
Our waveguide development initially relied on existing simulation tools. But a common challenge in optical design is balancing brightness and MTF (modulation transfer function), particularly with slanted and blazed patterns. To address this, we explored optimizing multiple organic materials at a binary level.
Despite these efforts, existing simulation tools proved insufficient for designing optimally tuned organic materials such as coatings and resins. In response, we developed a proprietary inhouse simulator that allows for precise optimization of organic material properties, which maximizes waveguide performance.
Unlike conventional waveguides that require an air layer and cover glass, Cellid has pioneered a fully laminated structure that eliminates the need for these components. This innovation results in a thinner, lighter lens, enhancing user comfort.
We continuously collaborate with industry partners to develop materials that align with our optimized simulations while ensuring durability against impacts, temperature variations, and other environmental factors. And to bring our advanced designs to life, we established a robust manufacturing ecosystem by partnering with leading companies within the semiconductor and related industries. This ensures high-precision production of our specialized waveguide structures.
By integrating these three key technologies—optical design, material innovation, and advanced manufacturing processes—we achieve superior waveguide performance to enable AR glasses that are both high-performing and practical for everyday use.
Importance of AR glasses comfort
While waveguide technology has the potential to revolutionize AR displays, one key factor that must not be overlooked is user comfort. For AR glasses to become widely adopted, they need to be lightweight and comfortable enough for extended use. A significant challenge is balancing the compact design of waveguides with the overall weight and ergonomics of the glasses.
Ensuring waveguide displays are integrated into designs that are lightweight, well-balanced, and have soft, adjustable components can be crucial. Comfort will determine whether AR glasses can transition from being a novelty or niche product to a mass-market device used for daily activities such as navigation, gaming, and communication. At Cellid, we are developing various ways to integrate comfortable, flexible materials into our designs without compromising the performance of the waveguides. By addressing these ergonomic needs alongside the advances in optical technology, we can ensure AR glasses are as comfortable as they are transformative.
What does waveguide technology enable?
Advancements in waveguide design are unlocking new possibilities for AR applications across multiple industries, including:
Ophthalmic use cases. We believe that ophthalmic AR glasses, which have the same shape as regular eyeglasses, will be the next major device after smartphones. Just as smartphones are used in various applications, AR glasses will be used by both individuals and companies for various use cases without limiting the industry.
Enterprise and industrial use. AR glasses with efficient waveguides enable real-time data overlay for technicians, reducing errors and improving productivity in sectors such as manufacturing, logistics, and healthcare.
Consumer AR. As waveguides become more compact and cost-effective, they will drive the adoption of AR glasses for everyday use, from navigation to gaming and social interactions.
Looking ahead: The next phase of AR waveguide innovation
During the next few years, significant AR waveguide technology advances are expected to transform both product capabilities and market adoption. We are working on several innovations aimed at increasing efficiency and reducing costs. These include ongoing refinements in materials science that will improve optical performance, enhance durability, and enable scalable manufacturing. Our innovations will lead to the wider availability of commercial AR waveguide products, while the development of ultrathin, flexible waveguides will make it possible to integrate displays seamlessly into lightweight AR glasses and wearable devices. Ultimately, these breakthroughs will pave the way for fully transparent, high-resolution AR displays that blend digital and physical realities—and revolutionize how people interact with information and the world around them.
Waveguide technology is at the heart of the AR revolution, paving the way for sleek, high-performance, and mass-adopted AR glasses. While challenges remain, ongoing materials, design, and manufacturing advances are steadily overcoming these obstacles. At Cellid, we are committed to leading this transformation—pushing the boundaries of what is possible and bringing the next generation of AR experiences to life.
The journey of waveguide development is just beginning, and its impact will be felt across industries and our lives in ways we are only starting to imagine. With continued innovation, collaboration, and perseverance, the dream of truly immersive and practical AR will soon become a reality.
Satoshi Shiraga
Satoshi Shiraga is the cofounder and CEO of Cellid Inc. (Japan), a developer of augmented reality (AR) waveguide technology. With over 20 years of experience in the field of optical design, Satoshi has been instrumental in advancing AR glasses, focusing on high-performance waveguides that enable the sleek, lightweight, and high-resolution devices needed for widespread AR adoption.
Before founding Cellid, Satoshi conducted particle physics research at prestigious institutions including CERN (European Organization for Nuclear Research), Fermilab (Fermi National Accelerator Laboratory, U.S.), and INFN (National Institute for Nuclear Physics, Italy). He holds a master’s degree in physics from Waseda University Graduate School, where he specialized in particle physics, and was later invited to serve as a researcher at Waseda University.