Bulletin No. 2, 2024

And the way the professor sees it, the opportunities are boundless. With silicon photonics, connections are no longer limited by their heat by-product, so not only are operations faster, but they also consume much less energy. “And it's not just in the communications industry,” he adds. “It could also improve the devices for healthcare: for example, in the optical coherence tomography (OCT) market, we use light to detect underneath the skin potential skin cancer, or other diseases through 3D imaging in real-time. Today, these are desktop-based systems that are not yet widely available; with this chip technology, we can reduce it to a tiny handheld platform. And we hope to make this so low-cost, that it becomes as cheap as a smart watch.” The professor is confident that OptiHK’s products can succeed because of their solid foundational research, which he and his team have conducted over the years. “The know-how that we have developed in our group is amongst the best in the world in silicon photonics. In terms of device design, we are leading the field in that we have the lowest loss between the chip and optical fibre using the manufacturable boundary technologies.” Far from hindering their prospects in the business world, Professor Tsang believes that their base in CUHK and the academic world has actually provided them with a leg up over traditional industry. “As a university-based group, we need to stay at the forefront of the technology, whereas in industry there is a lot of pressure to make products that make use of older, more mature technologies.” A bright future awaiting Although he remains firmly rooted in academia, Professor Tsang is still keenly aware of the need for students to develop their own business acumen. For some years, he taught an undergraduate course on engineering entrepreneurship. Many local students, he says, have “very little experience in the real world — they may understand mathematics, they may understand circuit design, but they don't really see how this can be put together for making products to make money.” As a result, he started a course that aimed to utilise his own exploits as an R&D director and help these students look beyond mere technical aspects. “Technology is an enabler, but if you want to make money, you need to make products that can sell, and to do that you need to offer your customer something that has value.” This is a philosophy that has also informed the professor’s work at OptiHK; although he currently acts as principal investigator for the company, he sees himself more as a mentor figure for an upcoming batch of budding students. “My motivation in doing this,” he says, “is to try to see how the fruits of the last 20 years of my research can benefit the wider society, as well as give meaning to the research of many of my students, to help them show that this technology can change the world.” He hopes that his guidance will allow the firm to survive and thrive in the long term. “Today, we take for granted microelectronic chips; in the future, maybe 30 years from now, every chip in every computer you buy will have some photonic technology.” Like former CUHK Vice-Chancellor and “father of optical fibres” Professor Charles K. Kao, Professor Tsang is devoted to the application of light in communications 25