Patent attributes
A probe, which includes a plurality of first optical fibers and a plurality of second optical fibers that are tied as a composite bundle at a distal end side with forming a center channel through which a treatment instrument can be drawn. The first optical fibers are tied as a first branch bundle at a proximal end side and the second optical fibers are tied as a second branch bundle that is separated form the first branch bundle at the proximal end side. With this construction, a treatment instrument is available even if the probe is drawn through a forceps channel of an endoscope because the treatment instrument can be drawn through the center channel formed in the composite bundle.