[SR Talks] ⑤ Interview with a Projector Optical Engine Expert at Samsung R&D Institute Japan-Yokohama

Q: Please briefly introduce yourself, Samsung R&D Institute Japan-Yokohama, and the kind of work that goes on there. What projects are you working on?

I am Katsutoshi Sasaki, responsible for Projector Optical Engine development at Samsung R&D Institute Japan-Yokohama(SRJ-Y). Established in 1997, our institute has been conducting cutting-edge research and development, focusing on strong fields in Japan, such as optical technology, material technology, and image processing technology. We develop technologies that are utilized in Samsung Electronics’ global products.

I joined SRJ-Y in 2006, and my primary specialization is in optical mechatronics. I also have optical design (lens design) skills and have developed various optical devices throughout my career. Since I was little, I was interested in cameras, so I majored in optical design at university and started my career at an optical company. Currently, I am in charge of developing a projector optical engine. The versatility of projectors allows us to adapt screen distance and size based on different situations. This opens up diverse user scenarios, and our goal is to materialize each one effectively.

Our team comprises experts in optics, optical sources, and optical mechatronics – essential disciplines for optical engine development. We focus on designing a products that meet the specifications decided upon through consultations with the headquarters. In close cooperation with our colleagues at the headquarters, we work diligently toward mass production.

Moreover, Japan boasts many exceptional optical component suppliers, so we actively pursue a Korea-Japan collaborative approach, leveraging their valuable experience and expertise.

Q: Please tell us about the importance of your research field or technology.

The projector optical engine is the core unit. It converts the light emitted from the light source into uniform illumination through lighting optics and leads it to a spatial optical tone element, known as a digital micromirror device (DMD). The DMD then processes the video light and projects it onto the screen by using projection optics.

In recent years, we have also developed an optical engine for ultra-short-throw (UST) projectors enabling the screen and projector to be positioned as closely together as possible. The UST is a reflective optical system featuring aspherical mirrors or freely curved mirrors on the front. By reflecting the image behind the projector with an aspherical mirror, the projection distance is reduced, allowing for the realization of a large screen. Installing the projector near the wall enables users to enjoy a large screen measuring 100 inches or more, making it an excellent substitute for large TVs in the living room. Although the design challenges are considerable, our team possesses the technological capability to accomplish this feat.

Recently, light sources have been transitioned from mercury lamps or LEDs to lasers, resulting in dramatic improvements in brightness and color reproduction. However, since laser output alone has limitations, having multiple light sources becomes necessary. Additionally, a technology capable of reducing speckle noise, a type of luminance distortion unique to lasers, is required. Our team possesses the technical know-how to achieve highly efficient and high-quality lighting optics, drawing from our extensive experience in dealing with various optical equipment.

Q: Can you tell us about any main achievements or rewarding moments in your research?

In the development of a projector optical engine, the lens performance, the brightness of the light source, color performance, etc., are all organically interacting factors. Furthermore, heat dissipation, which is related to controlling the temperature of the light source is also significant. Since it is necessary to balance these factors during development, we check tens, hundreds, sometimes thousands of combinations through simulations and derive an optimal configuration from it. However, since the compositions theoretically infinite, it requires a lot of time and effort. Nonetheless, I feel very satisfied when I can achieve my goals. As a result, the fact that our developed technologies have been applied to commercialized products and showcased at international exhibitions or applied in mass production is the most rewarding outcome for me.

Q: What is your vision for the future, and what goal would you want to achieve?

Realizing a virtual display similar to R2D2 from Star Wars is considered as one of the dreams of researchers. However, technological innovations for this are still far away. The market demand changes every day. As optical devices are diversified, launching new devices becomes very important. We believe that our mission is to continuously introduce differentiated products. To this end, we would like to pursue the creation of a new optical system that has never existed in the world. In the future, we will enhance the value of projected images in any space and strive to create an amazing visual experience in all situations in life.

Q: What advice would you give to aspiring engineers who wish to enter the field of optical engineering?

Light seems challenging to comprehend due to its invisibility. However, the achievements of pioneers such as Newton have made it possible to treat light phenomena mathematically. Today, numerous optical tools based on these theories have been developed, resulting in innovative applications utilizing light. Contrary to popular belief, understanding light isn’t complex; it’s actually quite familiar. By understanding the light correctly, we will gain diverse insights and deepen our comprehension. Advances in novel optical devices, such as vital sensing, spatial sensing, and optical communication continue to grow rapidly. undoubtedly, considering the myriad ways light can be harnessed will broaden the scope of further developments.