US 7,582,057 B2
Endoscopic system using an extremely fine composite optical fiber
Tomoaki Toriya, Sakura (Japan); Takashi Tsumanuma, Sakura (Japan); Kenichi Nakatate, Sakura (Japan); Takashi Ishii, Sakura (Japan); Kiyoshi Oka, Ibaraki-ken (Japan); Toshio Osaki, Yokohama (Japan); and Akiyoshi Hayakawa, Inuyama (Japan)
Assigned to Japan Atomic Energy Research Institute, Kashiwa (Japan); Fujikura Ltd., Tokyo (Japan); and Kawasaki Jukogyo Kabushiki Kaisha, Kobe (Japan)
Filed on Feb. 22, 2005, as Appl. No. 11/61,722.
Claims priority of application No. 2004-047579 (JP), filed on Feb. 24, 2004; and application No. 2004-242099 (JP), filed on Aug. 23, 2004.
Prior Publication US 2005/0192480 A1, Sep. 01, 2005
Int. Cl. A61B 1/06 (2006.01); A61B 1/04 (2006.01)
U.S. Cl. 600—160  [600/108] 17 Claims
OG exemplary drawing
 
1. An endoscopic system, comprising:
a composite optical fiber consisting essentially of
a large-diameter, laser light transmitting optical fiber and
a large number of image transmitting fibers that are bundled together to form an integral assembly with a central fiber,
the large-diameter optical fiber being surrounded by the image transmitting fibers and
the image transmitting optical fibers being fused to form a monolithic sea-island structure in which a large number of cores as islands are surrounded by a continuous phase of a cladding as a sea;
a laser treatment and image observing optical unit that is connected to an eyepiece portion of said composite optical fiber such that the unit launches laser light into said large-diameter optical fiber and such that an image being transmitted through said image transmitting optical fiber is focused on a camera to become observable, and
an illuminating light transmitting unit that transmits illuminating light to a tip of an objective portion of said composite optical fiber for irradiation purposes, where said illuminating light transmitting unit includes a light source and a light guide that transmits the illuminating light emerging from said light source, at least the tip portion of said light guide being made integral with said image transmitting optical fibers in its longitudinal direction, and
wherein said large-diameter, laser light transmitting optical fiber and said image transmitting optical fibers are each an optical fiber having a core and of which a core/cladding index difference Δ is 3.5 to 4%.