Patent ID: 6490039
Filing Date: 2002-12-03
Classification: G01N,G02B,H01S

Abstract:
A device, comprising:an optical resonator to support a whispering gallery mode of an electromagnetic field; an optical coupler positioned adjacent to said optical resonator and having an interfacing surface to evanescently couple optical energy into or out of said optical resonator in said whispering gallery mode; a sample unit disposed relative to said optical resonator to supply a sample to a spatial region within a reach of and to interact with said electromagnetic field of said whispering gallery mode to produce a change in said optical energy in said optical resonator; an optical detector located relative to said optical coupler to receive an output from said optical coupler and measure said change during a transient period before said optical resonator reaches an equilibrium state in interaction with the sample; and a signal processor coupled to said optical detector to process an output from said optical detector to extract information on the sample.