Patent ID: 7027705

Claim:
An optical-fiber feedthrough which has i) an optical fiber formed of a resin-covered portion at which the surface of an optical-fiber bare fiber is covered and an optical-fiber bare fiber uncovered portion standing uncovered from the resin-covered portion and provided on the outer surface thereof with a metallic film and ii) a metallic sleeve with which the optical fiber is fastened, and which is to be attached to the package sidewall of an optical communication module so that the optical fiber is guided into the optical communication module, wherein said metallic sleeve comprises: a sleeve main body having a first hollow portion which has an inner diameter greater than an outer diameter of the optical-fiber bare fiber uncovered portion in the optical fiber and into which the optical-fiber bare fiber uncovered portion is inserted, and a second hollow portion which communicates with this first hollow portion and which has an inner diameter greater than an outer diameter of the resin-covered portion in the optical fiber and in which an inserted portion of the resin-covered portion and an optical-fiber bare fiber uncovered portion standing uncovered from the resin-covered portion to lead to the first hollow portion are held; and a first conical recessed portion which is provided on the first hollow portion side of the sleeve main body and to which the leading end portion of the optical-fiber bare fiber uncovered portion is uncovered, the interior of said first conical recessed portion being filled with a solder to fasten the optical-fiber bare fiber uncovered portion to the metallic sleeve and also to close a gap between the first hollow portion and the optical-fiber bare fiber uncovered portion with the solder, and a gap between the second hollow portion and the resin-covered portion being filled with an adhesive to make the resin-covered portion fastened to the metallic sleeve, wherein the cutout is provided at the second hollow portion of said metallic sleeve, and wherein the leading end portion of the inserted portion of the optical fiber at its resin-covered portion is disposed at a position intermediate or substantially intermediate between said cutout and the open end portion of said second hollow portion on its side opposite to the first hollow portion, and said second hollow portion is filled therein with the adhesive at least up to an end of the cutout on its first hollow portion side, and also a hollow is formed between an end of the second hollow portion on its first hollow portion side and an end of the adhesive on its first hollow portion side with which the second hollow portion is filled.