Optical waveguide mode sensor having pores

A optical waveguide mode sensor comprising:

• a chip provided with a substrate formed from a transparent dielectric material or a transparent electrically-conductive material, a reflector film formed on the substrate, and an optical waveguide layer formed on the reflector film;
• a plurality of pores formed in the optical waveguide layer so as to penetrate the optical waveguide layer;
• a light-introducing mechanism that introduces light from the substrate side of the chip onto the reflector film;
• and
• a light-detecting mechanism that detects the light reflected on the reflector film;
• wherein a specimen under investigation is detected by sensing a change in the incidence angle or in an intensity of reflected light that occurs when the specimen is adsorbed or deposits on a surface of the optical waveguide layer, by using a range of incidence angles of the light in which the intensity of reflected light changes when a part or all of the incident light couples with the optical waveguide mode that propagates in the optical waveguide layer.