Ichirou ISHIMARU, Professor, D.Eng.
Kagawa University, Faculty of Engineering, Department of Intelligent Mechanical System Engineering.
Fields of Specialization: Biomedical engineering/biological material studies, Laser and Supersonic Wave Inspection, Intellectual Control, Measurement engineering, Intelligent mechanics/mechanical system, Measurement engineering

Substances are different on how much and what length of wavelength they can absorb. Measuring and visualizing it, spectroscopy can identify what it is without destroying substances. Many spectroscopic devices, using mid-infrared which can identify the amount of absorption on different wavelengths, have been built. However, the existing devices are gigantic as well as hefty price. It would cost more than 100 million yen and weigh 50kg even if it’s mobile type with full equipment. The reason why it costs so much is because the way applied to the existing devices, Fourier transform infrared spectroscopy, is susceptible to mechanical vibration and it’s necessary to have  anti-mechanical vibration systems. As a result, spectroscopy has been limited technology for specific companies or scientists, though it is quite useful way to analyze substances.

Under this circumstance, Professor Ichirou Ishimaru in Faculty of Engineering invented a compact middle-infrared spectroscopic imager, by using a new technology of an imaging-type Fourier spectroscopy method that has robustness against a mechanical vibration and he also succeed in weight saving and downsizing of spectroscopy dramatically. 　　Using this new method, he jointly developed a new model with the local semiconductor manufacturing company, AOI ELECTRONICS.Co.,Ltd., in Takamatstu, and it is a palm-sized and weighs only 500g. Now they are trying to make it even smaller so that it would be built on substrate with less than 1cm in width.

If spectroscopic devices would be smaller and cheaper, they bring us a lot of change in our daily life. For example, smartphones and smart watches with spectroscopic device could measure blood glucose level just by lighting on skin instead of the blood draw. Smart toilet could be developed which can measure the amount of albumin and check kidney function. They have been doing the research with Faculty of Medicine and will put a lot of effort to make it happen in near future. Handy devices that can check people’s health easily at home would be savior for Japan where cost of medical care is heavy burden due to aging.

In the craft products area, this new spectroscopy is useful to evaluate color of cubic objects. For example, it enables us to discern what kind of color material was used for old fine arts and crafts. “To confess, I decided to study science at a young age when I saw the TV program which featured a famous carpenter, Jouichi Nishioka, who was in charge of the large renovation of Houryuji Temple in Showa Era. I felt how cool the engineer was. That is the reason why I’m attached to historical buildings and crafts. I’m very intrigued by one of traditional crafts in Kagawa, Urushi (lacquer) Art, especially for an old type of Urushi arts which was painted by many colors in multiple layers. It would be very interesting to analyze an old Urushi art with spectroscopy” passionately said Professor Ishimaru. This new way is also helpful to analyze soil or seawater. Soil investigation is utilized for areas of agriculture and disaster prevention, and seawater investigation is helpful to check generation of the red tides of plankton concentrations in the sea. Compact devices can be loaded on drones as well as satellites that are anticipated an increase in launching. With those, we can also measure CO2 condition globally from space. “It is important how many high-tech devices can be loaded on drones and satellites so compact spectroscopic devices are very suitable for that purpose”, according to Professor Ishimaru.

There is also the potential to be used more industries than expected. “Once a new device came into a market, I’m expecting some companies or institutions who need it would customize it or develop an application for it” mentioned Professor Ishimaru. Actually there have been many inquiries from a wide range of industry. We will see the future in which a compact spectroscopy provides secure and comfort on many occasions from behind the scenes.

At FY2017 Japan Invention Prize that is held by Japan Institute of Invention and Innovation for the purpose of progress of science technology and development of the industry, Professor Ishimaru and Kagawa University got The Encouragement of Invention Prize and The Contribution of Invention Prize respectively. Professor Ishimaru, Dean of Kagawa University, and AOI ELECTRONICS.Co,,Ltd. attended the ceremony at Hotel Okura Tokyo on June 12.