THE STORY OF A LIGHTING REVOLUTION
Prof. Hiroshi Amano is a Japanese physicist and inventor specializing in the field of semiconductor technology. He was awarded the 2014 Nobel Prize in Physics together with Isamu Akasaki and Shuji Nakamura for the invention of efficient blue light-emitting diodes that has enabled bright and energy-saving white light sources. Currently, Prof. Amano is the Director of the Center for Integrated Research of Future Electronics (CIRFE) at the Institute of Materials and Systems for Sustainability (IMaSS), Nagoya University, Japan. Prof. Amano paid a visit to Sultan Qaboos University to explore research ties with the researchers and scientists in the University. Experts from his interaction with officials at SQU.
Could you explain on your invention of blue LEDs that revolutionized television and smartphone display technologies?
Prof. Amano: Lighting plays a crucial role in the quality of life of humans. The development of light-emitting diodes (LEDs) has materialized more efficient light sources. Creating white light that can be used for lighting requires a combination of red, green, and blue light. Blue LEDs proved to be much more difficult to create than red and green diodes. During the 1980s and 1990s our research team could successfully use the difficult-to-handle semiconductor gallium nitride to create efficient blue LEDs.
How did you develop interest in material science and engineering especially in the invention of blue LEDs?
Prof. Amano: I moved to Nagoya in 1979 to enter Nagoya University as a student of the Department of Electrical Engineering. In the introductory class to engineering, the lecturer explained that the ultimate goal of engineering is to enrich the lives of people. I was astonished with this explanation and felt that my view of study had suddenly opened through recognizing that the meaning of study is to benefit the people. As a result, I became interested in all fields of study offered by my department, particularly computer science. In 1982, when I was in my third year of university, I had to choose a dissertation research topic. Unfortunately, there were no topics concerning computer science, especially the design of central processing units. However, when I found that gallium nitride based blue LEDs could be researched in one of the labs, I decided to pursue this topic as my dissertation topic. At that time, Braun tubes were used as the monitors of PCs and in television systems. Because Braun tubes were so large, I thought that if I could develop blue LEDs, I could change the world by improving people’s lives by providing the means to develop smarter PC and TV systems. At that time, I did not know how difficult it would be to develop blue LEDs.
What are the other possible applications of blue LEDs?
Prof. Amano: Today, gallium nitride based LEDs are used in back-illuminated liquid-crystal displays in devices ranging from mobile phones to TV screens. LEDs emitting blue and ultraviolet (UV) light have also been used in DVDs, where the shorter wavelength of the light allows higher data-storage densities. Looking into the future, UV-emitting LEDs could be used to create basic yet effective water-purification systems, because UV light can destroy microorganisms. The UV-C wavelength range is the germicidal portion of the ultraviolet light section of the light spectrum which will deactivate the DNA in viruses and bacteria, effectively eliminating the chances of reproduction and thus disease. Once this occurs, the bacteria’s DNA is unable to duplicate itself, thus it is unable to reproduce and therefore dies.
What are your current projects and future research plans?
Prof. Amano: Currently our team is working on the applications of LED lights for water purification that I explained. We are conducting studies on wireless energy transfer technologies in order to make wireless charging of drones possible that makes them stay in the air 24 hours a day and 365 days a year. We are exploring the use of microwaves or laser beams to charge the drones without using any wires.
Could you comment on the purpose of your visit to SQU and its outcomes?
Prof. Amano: We are keen to explore ties with scientists at SQU in the fields of materials technology and related fields. In this regard, we held discussions with the Vice Chancellor and academics in physics and engineering faculties. The future is promising as we could identify areas of mutual interest such as use UV lights for water purification and wireless charging systems.