摘要：

An optical fiber made up of a core for propagating the light and a cladding covering the core for interrupting light propagated within the core. The optical fiber includes a tip formed by sharpening an end of the core in a tapering fashion, a light-shielding coating layer formed on the surface of the tip and an aperture formed by exposing the foremost part of the tip from the light-shielding coating layer to outside. With the present optical fiber, the light-shielding coating layer operates as a light shielding portion for interrupting the light radiated on other than the aperture and light enters or exits only at the aperture. The light propagated in the core is propagated in the core as it is repeatedly reflected at a core-cladding boundary and is collected at the tip so as to be radiated to outside via the aperture. The light entering the tip via the aperture is conducted into the core via the tip. The present optical fiber is used in for example, a photon scanning tunneling microscope for detecting the evanescent light locally present in an area smaller than the wavelength of light on the surface of a material, as a light probe which is positioned in proximity to the surface of the material for scattering and detecting the evanescent light. The light scattered at the foremost part of the tip is conducted via the tip into the core so as to be detected at the opposite end of the core. <IMAGE>

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