To intensify the Raman scattered light from a sample existing in the vicinity of a transition metal surface, and observe it with high sensitivity by resonantly exciting a surface plasmon(SPP) by using visible radiation by a total reflection attenuating(ATR) method.
The visible (p)-polarization incident light from a visible radiation irradiating device 4 is applied to a sample 3 on a base board 2 through a microscopic triangular prism 11 and a Weierstrass' δ prism 13. At this time, reflectance from the metallic base board 2 is monitored by a light detector 6, and a height from the optical axis of the prism 11 is controlled, and an illuminating angle 16 to a bottom surface 15 of the prism 13 is adjusted to a resonance angle of an SPP. A void thickness 18 between the bottom surface 15 and a surface of the base board 2 is directly observed in the rear of a condenser lens 12 through a interference fringe of the scattered light, and the base board 2 is pressed against the bottom surface 15 by a micrometer head, and is adjusted to an optimal thickness with every sample 3 to effectively excite the SPP. Therefore, a Raman hand from the sample (chemical species) 3 is increased by an increased local electrid field in the vicinity of a surface of the base board 2.
OTSUTOO ANDOREASU
JPH06265336A | 1994-09-20 |