Patent ID: 8193516

Claim:
A sensing apparatus for detecting an analyte in a sample with an aid of an enhanced field that is generated by causing light to strike a detection surface at a specified angle of incidence, comprising: a prism; a metal film provided on a surface of the prism; a substrate that is provided on a surface of the prism and which has formed therein a channel for supplying the sample to the metal film; a light source for issuing light; an optical unit for incident light by which the light being issued from the light source is launched into the prism at such an angle that the light is totally reflected on a boundary surface between the prism and the metal film to generate an enhanced field on the metal film, the optical unit for incident light including a light intensity distribution adjusting section that reduces difference between the maximum and the minimum values in the intensity distribution of the light that is launched into the prism to make an intensity of the enhanced field generated on the metal film more uniform; and a light detecting means for detecting the light emerging from the sample on the metal film.