Patent ID: 7423753
Filing Date: 2008-09-09
Classification: G01N

Abstract:
1. A fiber optical sensor for detecting an analyte in a sample, the fiber optical sensor comprising: an optical resonator having a multimode optical fiber, a first reflective layer adjacent to or on one end of the optical fiber and a second reflective layer adjacent to or on the other end of the optical fiber, the first reflective layer having a transparent hole defined therein; the surface of the optical fiber having an active region with a property of binding with the analyte when brought in contact with the analyte; a light source emitting excitation light to be coupled into the optical resonator through the transparent hole and the evanescent wave is generated at the active region of the optical fiber; a detector for detecting the fluorescent light generated by a fluorescent material excited by the evanescent wave in response to the presence or concentration of the analyte in the sample; wherein, after the light beam enters the optical resonator through the transparent hole, the light beam is reflected back and forth between the first and second reflective layers many times whereby the excitation light is effectively used to excite the fluorescent material, and the fluorescent signal is significantly amplified.