Abstract: The present invention relates to a surface interaction type multimode optical fiber coupler. A representative embodiment of the present invention comprises a plurality of optical fibers with at least one having an expanded core section. Sections of the optical fibers including at least a portion of the expanded core sections are fused together forming a fused section. At least one of the optical fibers is suitable for multimode operations. According to an embodiment of the present invention, a method of fabrication an optical fiber coupler comprises: providing a plurality of optical fibers with at least one having an expanded core section; and maintaining sections of the optical fibers including at least a portion of the expanded core sections in contact and simultaneously heating at least a portion of the sections that are in contact to form a fused section until a predetermined end condition is reached.

Abstract: According to an embodiment of the present invention an optical filter assembly, which is suitable for use in, for example an optical fiber system, comprises a focusing lens, an optical filter, and a first holder holding the focusing lens and the optical filter in position. A method for fabricating this optical filter assembly comprises: selecting a combination of focusing lens, optical filter, and the relative position and orientation of the focusing lens and the optical filter according to the desirable center wavelength characteristic of the optical filter assembly; and position and securing the focusing lens and the optical filter onto the first holder so that the focusing lens and the optical filter are substantially in the select relative position and orientation.

Abstract: The present invention relates to a surface interaction type multimode optical fiber coupler. A representative embodiment of the present invention comprises a plurality of optical fibers with at least one having an expanded core section. Sections of the optical fibers including at least a portion of the expanded core sections are fused together forming a fused section. At least one of the optical fibers is suitable for multimode operations. According to an embodiment of the present invention, a method of fabrication an optical fiber coupler comprises: providing a plurality of optical fibers with at least one having an expanded core section; and maintaining sections of the optical fibers including at least a portion of the expanded core sections in contact and simultaneously heating at least a portion of the sections that are in contact to form a fused section until a predetermined end condition is reached.

Abstract: According to an embodiment of the present invention an optical filter assembly suitable for use in, for example, an optical fiber system, comprises a focusing lens, a first holder holding the focusing lens; and an optical filter having a reflective surface attaching to the first holder optically coupling with the focusing lens. A method for fabricating an embodiment comprises positioning and securing the focusing lens and the optical filter on a first holder at predetermined positions. For setting the embodiment within a predetermined center wavelength range measured under a measurement condition, the method for fabricating the embodiment further comprises selecting an optical filter from a group of one or more optical filters of different center wavelengths and a focusing lens from a group of one or more focusing lenses of different focal length such that the selection will result in an embodiment that satisfies the center wavelength range requirement.