People behind the PICs | Douwe Geuzebroek

People behind the PICs | The Photonic Integrated Circuits (PIC) industry is booming. Companies in the field are growing steadily, start-ups with innovative solutions are popping up regularly, and the search for technical staff seems never-ending. In this interview series, we are curious to get to know the people behind the PICs. Who are the energy forces driving this technological revolution, and what motivates them? What can future photonics engineers expect from a career in this field?

In between the technology and the customer: that is the playing field where Douwe Geuzebroek is most comfortable. Already during his Electrical Engineering studies at the University of Twente, where he followed a minor in Business Administration, he started developing a view that was broader than “just the technical side of things”. After his PhD, he worked as a Design Engineer at LioniX and was actively involved in writing the first business plan of what would in 2008 become XiO Photonics. As Vice President of Marketing and Sales at this company, Douwe supported the development of the waveguide technology for visible light applications and the introduction of this technology in several products. After XiO Photonics merged into LioniX International, he held the same position for seven years. Since January 2024, he is working full-time as Chief Technology Officer at the start-up he co-founded: Brilliance RGB.

Douwe Geuzebroek, CTO of Brilliance RGB. Photography by Gijs van Ouwerkerk.

What made you decide to do a PhD in the field of photonics?

“This was a long time ago, during my master’s in the field of fiber optical networks. I was looking for what to do after and came across a PhD assignment in a different research group than my own. This project was looking at Photonic Integrated Circuits (PICs), which were new for me at the time, in optical network applications. I liked that crossover from networks to components, the way it was situated in between electronics and physics. That is how I ended up at the Lightwave Devices group, as it was called back then. This is the group where the majority of Twente’s integrated photonics professionals of my generation come from. My PhD was focused on micro-ring resonators in silicon oxynitride for telecommunication access networks.”

A few years after finishing your PhD, you became VP of Marketing and Sales at the newly found company XiO Photonics, and later at LioniX International. What made you decide to switch from technical-oriented positions to more commercial roles?

When I started at LioniX after finishing my PhD, I already had the aim of starting a new company which was targeting the market for micro-ring resonators. While I was working as a design engineer doing all kinds of things for customers as well as research projects, I was also involved in writing the business plan for XiO Photonics. When we started it in 2008, we were focusing on the field of telecommunications. Although we had two nice customers, the projects did not last as long as we planned due to the economic crisis at the time. It turned out telecom was not the best place to start and we had to shift our focus. We looked at what silicon nitride can do well compared to other materials. Where and how could it make an impact. The answer was visible light. We changed XiO’s proposition and started creating PICs using visible light, mainly targeting applications in the life sciences field. During this time, I learned a lot about using visible light, which is different from using infra red light like in telecom. I also learned a great deal about selling a module instead of selling a chip. So in 2016, when XiO Photonics merged with LioniX, I had already left the pure technology side of things for several years. My day-to-day activities had for a large part been about relating our technological capabilities to the problems that our customers and prospects were facing. Those interactions gave me a lot of energy and I decided to continue further on this path at LioniX International.”

Currently you are Chief Technology Officer at Brilliance RGB. How did you develop the vision of this start-up? Where do you see it going in the next five to ten years?

“The idea for Brilliance was already in our minds when we were working on life sciences at XiO. This was the time just before the iPhone. There was a lot of talk about micro-projectors – having something in your hand  that projects onto the wall – but the market was not there yet. Now, the market for Augmented Reality (AR) is fully there. And so are the lasers supporting it. So about two years back, we started working on it again and Brilliance was born.

Brilliance makes the smallest RGB laser engine for AR. RGB lasers are laser systems with three color modules: red, green and blue. By combining the three colors, whitelight laser effects are possible. Our aim is to make a product that goes into consumer headsets, such as AR goggles. The added value of using lasers is threefold: their intensity ensures you can use the glasses outside without the need for shades, they are small and lightweight which is vital for something you wear the whole day, and lastly, since we are using wafer scale processes, the fabrication of lasers is scalable.

My belief is that in five to ten years, it will be very normal for people to wear advanced glasses. In some industrial settings, they are already used. The question is not if they will come but how big they will be. Will it be a gadget that you only wear during sports, for example, where the information on your smart watch will be projected onto your glasses, or will it fully replace your smartphone or smart watch. You can dream very big about the kinds of applications these glasses will be used for. Productivity applications are targeted more and more, Apple is a big player in this field. Meta, on the other hand, is working on creating more intelligence in gaming. I personally think the killer application is not there yet. There are so many applications we have not thought of yet that will be normal in a few years. AI will have a big role to play in this. I like to relate it to the mobile phone. When it was just created, people said they would never walk around all day with such a thing. Nowadays, the issue is people spend too much time on it. In any case, we do not have to convince investors the market for these glasses is coming. It is already there.”

Douwe Geuzebroek, CTO of Brilliance RGB. Photography by Gijs van Ouwerkerk.

What is something you are working on right now that really excites you?

A big part of getting Brilliance to work is the way we attach the visible laser diodes to the chip. We do that not with a butt end coupling but with a flip chip inside. We etch a hole inside a silicon nitride chip and we flip chip a laser in there with great precision, as optical modes are very small. As far as I know, nobody has done this with all three colours before. We are the first ones to do it with visible light. This is how we were able to raise money and create demonstrators. The next step is proving we can scale it into large volumes. The fact that we are creating so many possibilities for our customers with this technology is what gets me out of bed every morning.”

How do you explain your job to people outside of this industry? How do you make it understandable and exciting?

“I make it very concise by saying I make an extremely tiny laser for a glasses that you can play games on. That is what I tell my kids. And my wife as well by the way.”

How do you combine your technical knowledge with your business knowledge in day-to-day tasks?

“For me, it is a logical and natural thing. If I see a problem in the market I want to solve it with a technological means. If I see a promising technology, I want to see how the world can use it. I have never seen myself as a scientist but always as an engineer. On a day-to-day basis, it feels very logical for me to have the scope of these two. For an engineer, however, what can be a challenge is knowing too much about a topic. If you are working on something on a very detailed level, you mainly see the limitations, not the possibilities. But sometimes the limitations do not matter. If a customer can be helped with 80%, it is good enough to move forward. Hans van den Vlekkert, one of the founders of LioniX, taught me that you have to sell what is available tomorrow. When you are in a field that is still developing itself, you can never be 100% sure that the product you are selling will deliver on its promise. For some engineers, that level of uncertainty is a difficult thing to deal with. On the other hand, I come from an area where there is a lot of technology push. The field of photonics in general is like that. The gap between technology and product has been big for the most part of my career, so it has always felt natural for me to try and make it smaller. You can not do that by focusing only on engineering or only on customer wishes. It is about the area in between.”

What did you enjoy the most about the process of founding a company? What was the least enjoyable?

“The least enjoyable is that it always takes more time than you think. There are a lot of legal and administrative tasks to fulfill. And we are in a climate where getting funding is not a fast process, which is both a good thing and a bad thing I suppose. The most enjoyable is that you create something that is not there. This resonates well with my engineering heart. I also really enjoy learning from other people’s views. My co-founder Tim Tiek comes from the automotive field. This field has first-hand experience of what it truly means to go to real volumes. It is a long way and in order to achieve this in photonics, we need people from outside the field as well.”

In which application areas do you think PICs have the most potential?

“There are many to name here: LiDAR, data centers, connecting electronics and photonics, quantum, invisible light, heads-up displays. In the medical field, you can think of all kinds of applications using light that can achieve high volumes. Rockley Photonics is working on an application in the Apple watch that I find really cool: a sensor that uses photonic chips to measure glucose levels. Moreover, what I have learned at LioniX is that light can be used to measure and sense a great deal of things. Aside from the big volume applications, there are also many applications you can think of that will be produced in smaller volumes and still make an impact.”

How do you experience the European PIC ecosystem?

“I am a proud part of it. Western Europe has always been at the forefront of this technology and we overlook how good of an ecosystem we have here. I trust my neighbour and my neighbour trusts me that together we can make a better business. This mindset is different from what you see in some other environments. It might have to do with the fact that we are dealing with a lot of medium sized companies and we cannot do everything ourselves. Therefore, we need to cooperate. Cooperation builds trust and trust brings you further. When I look at my own company, I can proudly say that I have a start-up with twenty years of experience. I can fall back on things that LioniX, PhiX and JePPIX have learned. I stand on the shoulders of others. This is especially important in a deep tech setting like photonic integration.”

Is there somebody in the PIC industry that inspires you? And why?

“I can only give the biggest credits to the founders of LioniX: René Heideman and Hans van den Vlekkert. They were among the first people to start a business in integrated photonics in the Netherlands, back in 2001. Starting a company and combining technology development and business aspects with taking good care of your employees, inspires me a great deal. Especially considering the field was not as widely supported yet as it is today: there was no PhotonDelta, no JePPIX, et cetera. Both René and Hans taught me that it starts with taking good care of the people around you. I always find it funny to see how many of the people I work with are somehow connected to each other. Recently, one of the new guys at LioniX happened to read the acknowledgements of my PhD thesis where I thanked all my co-workers. He told me: I know all of them, they are still around!”

What has been challenging in your career and what was the most rewarding?

“When I look back, I am really happy with the choices I made. I have always worked for smaller companies, where the atmosphere is much more personal and flexible. I don’t mind putting in a lot of hours, but I also have a family to take care of so I am really glad that I was able to set up a good work-life balance for myself. I am also very much a people person and the connection with my colleagues has always been about the person, not about the position somebody has. In short, I would not have done anything differently. Yes, there were challenging times and not everything went according to plan, but in my opinion that is not a bad thing. You should not be afraid to fail or worry about things taking longer than you expected. There are always learnings to take from that.”

Do you have any tips for people starting out in the field of photonics, or things they should keep in mind?

“I would definitely tell them to stay in this field. I would have told my younger self that as well. Of course, it really depends on what people want for themselves. If you want everything to go according to plan, then this is probably not a good field to be in. Things change so much that it is hard to know where you will be in five years. For me, that is something positive. I would say that if you are somebody that does not mind to let things run its course and you enjoy working in a team, photonics is a great field for you. I have played baseball for a long time and what I like about it the most is that you cannot excel if you do not have a good team. It is the same in photonics, at least in the smaller companies that I have worked for. If trouble rises, and it most likely will, you can achieve a lot more in a team than by yourself. We have an incredible integrated photonics ecosystem here, don’t hesitate to take advantage of it.”

Curious to know which job opportunities the photonic integration community has to offer? Check out our career page.