Patent ID: 8477312

Claim:
A total reflection illuminated sensor chip, which is employed in a detecting method for detecting a detection target substance including the steps of supplying a liquid sample that includes the detection target substance onto a metal film formed on a surface of a dielectric prism, irradiating a measuring light beam onto the interface between the dielectric prism and the metal film such that conditions for total reflection are satisfied at the interface, and utilizing evanescent waves which are generated due to the irradiation of the measuring light beam to detect the detection target substance, the total reflection illuminated sensor chip comprising: the dielectric prism, which is formed by a synthetic resin material; the metal film; and a lid member or a side wall material, which forms a flow channel on the dielectric prism such that the metal film is included within the flow channel, wherein polishing streaks in the region of a metal film formation surface of the dielectric prism, on which the metal film is formed, have directional properties with respect to a single direction; and wherein projection vectors that represent components of the measuring light beam, which are projected onto the metal film formation surface, are substantially parallel to directional vectors that represent the directional properties of the polishing streaks.