Optical fiber holder and fusion splicer

An optical fiber holder configured to hold an optical fiber cable including an optical fiber strand and a sheath covering the optical fiber strand, and to expose the optical fiber strand to an outside, the optical fiber holder comprising:

• a base portion having a placement surface on which the optical fiber cable is placed;
• and
• a lid portion configured to be openably and closably attached to the base portion to cover at least a part of the placement surface,
• wherein the lid portion includes one or a plurality of pads facing the placement surface and pressing the optical fiber cable against the placement surface in a state where the lid portion is closed, and an angle defining portion that is located closer to a lead-out tip of the optical fiber strand than all the pads in an extending direction of the optical fiber strand, and that covers the optical fiber strand exposed from the sheath to define a lead-out angle of the optical fiber strand,
• the angle defining portion includes a first groove and a second groove,
• the first groove is provided to accommodate a first optical fiber strand having a first outer diameter, which is the optical fiber strand, and defines a lead-out angle of the first optical fiber strand,
• the second groove is provided at a central bottom portion of the first groove, is provided to accommodate a second optical fiber strand having a second outer diameter smaller than the first outer diameter, which is the optical fiber strand, and defines a lead-out angle of the second optical fiber strand, and
• the first groove and the second groove extend, in the extending direction of the optical fiber strand, from a first end surface of the angle defining portion close to the pads to a second end surface on an opposite side of the angle defining portion from the first end surface.