Abstract: An adapter includes a tubular body having a tubular shape and surrounding a pair of ferrules over half a circumference or more with a ling along a first direction as an axis. The tubular body includes a guide extending in the first direction and engaging with side surfaces of the ferrule, and a slit formed from one end to the other end in the first direction.

Abstract: A ferrule includes a first end surface and a second end surface, an outer surface, an accommodating part, a plurality of guide grooves, a window part, and a pressing part. The plurality of guide grooves are provided to each extend in the first direction on an inner wall of the accommodating part and be aligned in a second direction intersecting the first direction. The window part opens at the outer surface and is connected to the accommodating part. The pressing part is disposed in the window part to press the plurality of optical fibers toward the plurality of guide grooves. The window part is provided at a position facing at least a portion of the plurality of guide grooves. The pressing part can be fitted into the window part so that a gap is provided between an inner wall of the window part and the pressing part.

Abstract: A ferrule includes an optical fiber holding portion configured to hold a plurality of optical fibers, and a first side surface and a second side surface facing each other in a second direction intersecting a first direction in which the optical fiber holding portion extends. The first side surface is provided with a first recessed portion or a first protruding portion extending along the first direction. The second side surface is provided with a second recessed portion or a second protruding portion extending along the first direction. In this ferrule, the first recessed portion or the first protruding portion includes a first positioning portion and a second positioning portion separated from each other in the first direction.

Abstract: A ferrule includes a first end surface and a second end surface, an outer surface, an accommodating part, a plurality of guide grooves, and a first window part and a second window part. The plurality of guide grooves are provided to each extend in the first direction on an inner wall of the accommodating part and be aligned in a second direction intersecting the first direction. The first window part and the second window part open at the outer surface and are connected to each other through the accommodating part. The first window part is positioned on the first end surface side with respect to the second window part. The first window part is provided at a position through which at least a portion of the guide grooves are visually noticeable.

Abstract: A ferrule includes: a tip surface; an opening portion provided on a side opposite to the tip surface in a first direction intersecting the tip surface; a plurality of fiber grooves extending along the first direction and arranged along a second direction intersecting the first direction between the tip surface and the opening portion, the plurality of fiber grooves being capable of respectively supporting a plurality of optical fibers; and a plurality of lenses respectively disposed on extension lines of the plurality of fiber grooves. The fiber groove has a first fiber groove portion for positioning the optical fiber with respect to the lens and a second fiber groove portion for introducing the optical fiber into the first fiber groove portion. The first fiber groove portion is disposed closer to the lens than the second fiber groove portion in the first direction.

Abstract: An optical connector includes: a plurality of optical fibers each having a coating removal portion where a predetermined length of coating is removed from a tip; and a ferrule having a main body portion holding the coating removal portion of each of the optical fibers and a lens portion facing the tip in a first direction in which an optical axis of each of the optical fibers extends. The main body portion has a base portion including a plurality of fiber grooves respectively supporting the coating removal portions of the plurality of optical fibers. The plurality of fiber grooves extend along the first direction and are arranged along a second direction intersecting the first direction. The base portion has a recess portion between the fiber grooves and the lens portion in the first direction.