Active chemical sensing using optical microcavity

摘要

A sensor comprises a pair of mirrors (11, 12) opposed along an optical axis and shaped to provide an optical cavity with stable resonance in at least one mode and having a cavity length of at most 50 μm. An actuator system is arranged to move the mirrors relative to each other along the length of the optical cavity for tuning the wavelength of the mode of said cavity. A chemical sample is introduced inside the optical cavity using a sample introduction system (21). An EM radiation source (20) illuminates the cavity and a detector (25) detects the EM radiation emitted from, transmitted through, or reflected from the optical cavity.