Optical fiber having core with sharpened tip protruding from light-shielding coating

摘要

PCT No. PCT/JP95/01068 Sec. 371 Date Feb. 25, 1997 Sec. 102(e) Date Feb. 25, 1997 PCT Filed May 31, 1995 PCT Pub. No. WO95/33207 PCT Pub. Date Dec. 7, 1995An 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. 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, and light 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 via the aperture. The light entering the tip via the aperture is conducted into the core via the tip.