[17p-A404-1~14] 3.16 Optics and Photonics English Session

▲ [17p-A404-7] Transmission Surface Plasmon Resonance Image Detected by Smartphone Camera

〇Chutiparn Lertvachirapaiboon¹、Akira Baba¹、Kazunari Shinbo¹、Keizo Kato¹ (1.Niigata Univ.)

キーワード：Transmission surface plasmon resonance

Transmission surface plasmon resonance image (TSPRi) using plasmonic grating structure was investigated by the combination with smartphone camera. Since a detected range of smartphone camera was capable of detecting under visible light region, the TSPR substrate that provided a corresponding TSPR excitation wavelength was developed. The TSPR excitation at 650 nm was acquired from gold-coated CYTOP grating substrate. The TSPR excitation was observed entire visible light region up on the light incident angle. At light incident angle of 5^o, TSPR excitation wavelengths were observed at 930.6 and 574.1 nm. When the light incident angle was turned to higher angle, two surface plasmon (SP) modes that were SP⁰ and SP^-2 were observed. Although the calculated SP dispersion curves did not perfectly fit with the experimental results, the shifts of TSPR excitation wavelengths were relevant to those calculated SP modes. When the light incident angle was turned to 30^o, both SP modes were coupled to single mode resulting in the huge increase of TSPR intensity. The SP coupling effect was confirmed by the shift of TSPR excitation from conventional modes (water (CYTOP)/Au grating substrate) of SP⁰ and SP^-2 modes to SP coupling mode (water/Au grating/CYTOP substrate). The smartphone camera was then used as a detector. The extraordinary transmitted signal at the light incident angle of 30^o and at the wavelength of 675 nm that was TSPRi was observed. The transmitted signals detected by smartphone camera corresponded very well with spectroscopic data. This technique could be further developed for portable devices for sensor applications.