Optical fiber with tapered end of core protruding from clad

摘要

PCT No. PCT/JP94/00906 Sec. 371 Date Jan. 17, 1997 Sec. 102(e) Date Jan. 17, 1997 PCT Filed Jun. 3, 1994 PCT Pub. No. WO95/25972 PCT Pub. Date Sep. 28, 1995An optical fiber made up of a core for propagating the light and a clad covering the core for confining the light propagated in the core. The optical fiber has a tapering protrusion at the apex for entrance and exiting of light. The optical fiber is used in a photon scanning tunneling microscope detecting the evanescent light localized in an area smaller in size than the wavelength of light on the surface of an sample as an optical probe disposed in proximity to the surface of the sample for scattering the evanescent light for detecting the scattered light. The optical fiber is optically coupled to an optical waveguide for constituting an optically coupled element. With this optically coupled element, a protrusion of the optical fiber operates as a collection unit for collecting the light propagated in the core. The light collected by the protrusion enters the optical waveguide.