Abstract: The invention relates to a method of producing a preform for a holey optical fiber, and more particularly, to a method of producing polymer holey optical fiber using novel capillary and cane designs that allow a construction of complex holey structures. The capillaries may have a complex internal structure including multiple holes, holes of non-circular shape, off-center holes, holes of different sizes, or any combination of these. The canes may have a complex external shape to define interstitial holes when the canes arc combined in a stack (see FIG. 1). The capillaries and canes may be made of different materials and combined within the same structure.

Abstract: The invention relates to a method of producing a preform for a holey optical fibre, and more particularly, to a method of producing polymer holey optical fibre using novel capillary and cane designs that allow a construction of complex holey structures. The capillaries may have a complex internal structure including multiple holes, holes of non-circular shape, off-centre holes, holes of different sizes, or any combination of these. The canes may have a complex external shape to define interstitial holes when the canes arc combined in a stack (see FIG. 1). The capillaries and canes may be made of different materials and combined within the same structure.

Abstract: This invention relates to a method of producing a preform for an optical fibre. More particularly, the present invention relates to a method of preparing preforms for the production of holey optical fibres. The invention provides a method of producing an optical fibre, said method comprising applying heat to the interior of a preform and subsequently drawing said optical fibre from said preform. The invention also provides a method of producing an optical fibre, said method comprising preparing a preform comprising a body of optically suitable material and removing material at predetermined locations in the body so as to provide a plurality of holes within the body, applying heat to the interior of the preform and subsequently drawing said optical fibre from said preform.

Abstract: This invention provides an optical fibre (1) incorporating a body (2), and an array of longitudinally extending holes or inclusions (3) formed in the body (2), the holes or inclusions (3) having a different refractive index from the surrounding body (2) and being arranged to form a full or partial ring structure (5) extending generally around a longitudinal axis of the fibre, the ring structure (5) being disposed so as to approximate the refractive or reflective transmission characteristics of a multi-layer optical fibre. The fibre (1) may have a solid core or a hollow air core. The invention also provides a method of forming the microstructured optical fibre (1).

Abstract: An optical fibre (20) is disclosed, the fibre is adapted in a manner such that it guides an optical signal substantially only in one non-degenerate mode, wherein an electro-magnetic field carrying the optical signal is symmetric with respect to rotation about the fibre axis. Preferably, the non-degenerate mode is the TE01 mode. In one embodiment, the optical fibre (20) includes a central hole region (22) surrounded by a concentric guiding region (24), which is in turn surrounded by a concentric cladding region 826). The guiding region (24) may comprise a Bragg reflector region. Through appropriate selection of design parameters of the fibre (20), the effective refractive index for the TM01 mode can be reduced relative to the TE01 mode to make it below a refractive index of the cladding region (269, resulting in leaking of the TM01 mode into the cladding region (26).