Optical device, optical processing device, and method of producing the optical device

An optical device comprising:

• one or more optical fibers each including a core and a cladding surrounding the core;
• and
• a holder including:
• a supporting block having one end, an other end, and a supporting portion supporting the one or more optical fibers, the one end including a first, a second, and a third end surface;
• a reflecting plate provided on the third end surface, the reflecting plate having a reflective surface;
• and
• an intermediate layer including an optical resin provided between the third end surface and the reflecting plate, the intermediate layer having a refractive index comparable to a refractive index of the claddings of the one or more optical fibers, wherein
• the supporting portion extends in a direction of an axis from the on end to the other end,
• the first end surface of the one end extends from a bottom surface of the holder to the claddings of the one or more optical fibers along a first reference plane that intersects the axis,
• the second end surface of the one end and a lateral surface of the reflecting plate extend along a second reference plane in which lies the axis,
• the third end surface of the one end extends along a third reference plane that is oblique with respect to the axis at an angle greater than zero degrees and less than 90 degrees,
• the claddings of the one or more optical fibers are positioned in the second end surface,
• the one or more optical fibers have respective facets exposed in the third end surface, and
• the intermediate layer fills a gap between the facets of the one or more optical fibers and the reflective surface of the reflecting plate to thereby embed roughness of the facets exposed at the third end surface.