Abstract: An apparatus includes an optical adaptor having monolithically integrated optical elements and first micro-mechanical features, the latter defining at least a first horizontal reference surface and a first vertical reference surface; wherein the first horizontal reference surface is perpendicular to an optical plane, the latter being perpendicular the optical axis of the optical elements; and wherein the first vertical reference surface is perpendicular to the first horizontal reference surface and parallel to the optical axis.

Abstract: The present invention provides a tunable optical frequency converter based on an amplitude modulator, which comprises a laser, a first optical isolator, a circulating frequency conversion module. Said circulating frequency conversion module is composed of an optical coupler, an amplitude modulator, an optical amplifier, a second optical isolator, a first optical circulator, an optical fiber Bragg grating, a second optical circulator, a tunable filter and a tunable attenuator. Light outputted by said laser is inputted to said circulating frequency conversion module to conduct frequency converting repeatedly after passing through the first optical isolator, and then separated by a tunable filter and a second optical circulator, then the frequency converted light is outputted from the port of the circulating frequency conversion module.

Abstract: An optical fiber module includes an optical transmission line and a fiber stub structure. The optical transmission line has an optical fiber core, a coating enclosing the optical fiber core and a buffer layer enclosing the coating. A part of the optical fiber core is exposed to outer side of a free end of the optical transmission line. The fiber stub structure includes a sleeve and a ferrule. The sleeve has an internal central hole for accommodating the optical transmission line and an oblique hole in communication with the central hole for accommodating the ferrule. The ferrule has an internal passageway for accommodating a part of the optical fiber core of the optical transmission line. When installed, under the restriction of the oblique hole, the ferrule is disposed in the sleeve in an inclined state.