Patent ID: 8026494

Claim:
A fluorescence detecting method, comprising the steps of: preparing a dielectric plate, and a metal film which is provided at a predetermined region on one surface of the dielectric plate, onto which a sample that includes a detection target substance and fluorescent labels is supplied; irradiating an excitation light beam through the dielectric plate such that it enters the interface between the dielectric plate and the metal film, to cause a first electric field enhancing field to be generated on the surface of the metal film; detecting fluorescence emitted by the fluorescent labels due to excitation by the first electric field enhancing field with a first photodetector; detecting the amount of the detection target substance based on the intensity of fluorescence detected by the first photodetector; irradiating a reference light beam having a longer wavelength than the excitation light beam through the dielectric plate, to cause a second electric field enhancing field to be generated on the surface of the metal film at the same location as the first electric field enhancing field; detecting scattered light of the second electric field enhancing field, which is substantially proportionate to the intensity of the second electric field enhancing field, with a second photodetector; estimating the intensity of the first electric field enhancing field based on the relationship between the intensity of the first electric field enhancing field and the intensity of the second electric field enhancing field, using the intensity of the scattered light detected by the second photodetector; and normalizing and correcting the intensity of fluorescence with respect to the intensity of the first electric field enhancing field.