1Advanced technologies for mobility (CASE)
We "see" various things in our daily lives through light. However, there is also light that we cannot perceive, meaning it is invisible to our eyes. Recently, there has been progress in the development of mobility that utilizes this invisible light, with applications expected in features such as collision prevention. We are exploring new possibilities for mobility through research on sensors that can detect this invisible light, aiming to develop in-vehicle sensors that improve safety and comfort.
1）Invisible light detection technology : Diffraction grating-type SPR infrared spectroscopic sensor
The IMRA Japan sensor consists of a diffraction grating (periodic groove) on a silicon substrate and a thin film of gold on top of it. This diffraction grating structure causes a physical phenomenon known as surface plasmon resonance (SPR) when light with a specific wavelength at a specific angle is incident, resulting in the generation of an electric current. By utilizing this phenomenon, the wavelength component of the incoming light can be determined through the incident angle and the generated current value (spectroscopy). Normally, silicon cannot detect infrared light, but our diffraction grating structure with a gold thin film enables the detection of infrared light by utilizing the SPR phenomenon. This research and development of “Technology for detecting infrared light and analyzing wavelengths" will contribute to the development of in-vehicle sensors that see invisible light.
Operating principle
