Abstract: A short optical fiber 2 is incorporated in a ferrule 1 having a polished front end, so as to be projected from the rear end of the ferrule. In a base member 3 in which the short optical fiber is to be fitted into a hole 3b, a V-groove 3d to which the glass portion of an optical fiber is to be fixed, and a V-groove 3e to which the coated portion is to be fixed are formed. A cover member 4 is placed on the base member. The base member 3 and the cover member 4 are clamped by clamp members 5a and 5b and the base member 3 presses to V-grooves. Wedges which are not shown are pressingly inserted between recessed 3g and 4c, and 3h and 4d, and an optical fiber 10 is inserted from the rear portion. Thereafter, the wedges are detached and the optical connector is attached to the terminal of the optical fiber 10.

Abstract: An optical connector is provided where an biasing device 26 which biases a ferrule 24 having an optical fiber 22 secured thereinside and a tip end face 23 which has been polished, in a tip end face 23 direction, is located to the rear of a connection mechanism 25 for connecting the optical fiber 22 on the ferrule 24 side and a separately inserted optical fiber 22a, at a rear end side of the ferrule 24 opposite to the front end face 23. The connection mechanism 25 has a construction which uses a mechanical splice, and is opened and closed by a release member inserted into an insertion opening 39 which is opened along an alignment axis direction. Hence the opening and closing operation does not interfere with the biasing device 26, so that operability is improved. Moreover, for this type optical connector there is provided an optical connector housing 21 which accommodates the ferrule.

Abstract: A spacer having a high-tensile member at the center thereof has grooves extending helically. Coated optical fibers have been disposed in each groove. This assembly is covered with a wound covering and further with a sheath. The proportion of the total sectional area of the coated optical fibers to the sectional area of each groove, i.e., the degree of packing, is regulated to 10 to 50%.

Abstract: A short optical fiber 2 is incorporated in a ferrule 1 having a polished front end, so as to be projected from the rear end of the ferrule. In a base member 3 in which the short optical fiber is to be fitted into a hole 3b, a V-groove 3d to which the glass portion of an optical fiber is to be fixed, and a V-groove 3e to which the coated portion is to be fixed are formed. A cover member 4 is placed on the base member. The base member 3 and the cover member 4 are clamped by clamp members 5a and 5b and the base member 3 presses the V-grooves. Wedges which are not shown are pressingly inserted between recesses 3g and 4c, and 3h and 4d, and an optical fiber 10 is inserted from the rear portion. Thereafter, the wedges are detached and the optical connector is attached to the terminal of the optical fiber 10.

Abstract: An optical drop cable-units cable comprising a plastic pipe and a plurality of strandless optical drop cable-units and held in the plastics pipe, in which a space factor(B.times.n/A).times.100(%).ltoreq.51%whereA: void cross-sectional area of the plastic pipe,B: a cross-sectional area of a single optical drop cable-unit, andn: number of optical drop cable-units.

Abstract: The optical connector according to the present invention comprises, at least, an optical filter with a waveguide structure having a grating with a predetermined reflection wavelength and a plug attached to a tip of the optical filter. The grating is disposed at a tip portion of the optical filter and accommodated in the plug attached to the tip portion of the optical filter. Further, the optical connector has various light-blocking structures for preventing unnecessary light from traveling a filter region of the optical filter including the grating.