An IR-transmitting glass fiber configured to include a holey-microstructured core and a cladding surrounding the core. Glass material used at least in the core is one of the heavy metal oxide glasses, where the glass network former is an oxide selected from GeO.sub.2, TeO.sub.2, Sb.sub.2O.sub.3, and Bi.sub.2O.sub.3, while each and every component of the fiber includes only an oxide glass material and is devoid of any other materials.

A distributed gas detection system includes one or more hollow core fibers disposed in different locations, one or more solid core fibers optically coupled with the one or more hollow core fibers and configured to receive light of one or more wavelengths from a light source, and an interrogator device configured to receive at least some of the light propagating through the one or more solid core fibers and the one or more hollow core fibers. The interrogator device is configured to identify a location of a presence of a gas-of-interest by examining absorption of at least one of the wavelengths of the light at least one of the hollow core fibers.

An anti-torsion solid-core polarization-maintaining photonic crystal fiber includes a cladding having an inner layer arranged around the core and an outer layer between the inner layer and the outer wall of the cladding. The inner layer has multi-layer air holes used to construct optical properties and two micron-size air holes arranged along the x-axis extending in the center producing form birefringence. The outer layer includes multi-layer air holes arranged radially along the y-axis. The size and arrangement of the multi-layer air holes in the outer layer cause the bending stiffness of the photonic crystal fiber along the x-axis to be different from that along the y-axis. While meeting the requirements of the optical properties of the fiber, the photonic crystal fiber possesses an anti-torsion ability due to the anisotropy of stress distribution in the radial direction, thereby reducing the non-reciprocal phase difference generated by the magneto-optic Faraday Effect.

A shaped tube (50,51) for use as a component in the fabrication of an antiresonant hollow core optical fibre, the shaped tube having a side wall with a transverse cross-sectional shape comprising a number of major curved portions (52) alternating with the same number of minor substantially straight portions (54), each curved portion (52) having an inwardly curving shape, and each straight portion (54) being equidistant from a central longitudinal axis of the shaped tube (50,51).

A preform for making a vortex optical fiber comprises a glass cylinder formed substantially of silicone dioxide that defines a core portion along a longitudinal axis of the glass cylinder and a cladding portion surrounding the core portion. The glass cylinder further defines a plurality of holes running parallel to the longitudinal axis from a first end of the glass cylinder to a second end of the glass cylinder.

The disclosure relates generally to optical systems, and more particularly, optical systems for temporal compression or stretching of optical pulses.

The present invention, as disclosed and described herein, in one aspect thereof comprises a preform for making a vortex optical fiber includes a glass cylinder formed substantially of silicone dioxide that defines a core portion along a longitudinal axis of the glass cylinder and a cladding portion surrounding the core portion. The glass cylinder further defines a plurality of holes running parallel to the longitudinal axis from a first end of the glass cylinder to a second end of the glass cylinder.

A device for transporting pulsed laser radiation includes a pulse duration setting device configured for setting a transport pulse duration of the pulsed laser radiation. the device further includes a hollow core optical fiber having a hollow core surrounded by a material. The hollow core optical fiber is configured to be operated with beam path parameter values that are present at the first fiber end and lie in a target tolerance range. The device further includes a fiber input coupling device configured to couple the pulsed laser radiation into the hollow core optical fiber with the beam path parameter values that lie in the target tolerance range. the transport pulse duration is set so that input coupling of the pulsed laser radiation into the hollow core is provided for all of the beam path parameter values in the target tolerance range.

A technique for fabricating a hollow core optical fiber with a controllable core region (in terms of diameter) is based upon regulating conditions (gas flow, volume, and/or temperature) within the hollow core region during the fiber draw process. The introduction of a gas, or any change in volume or temperature of the hollow core region, allows for the diameter of the hollow core region to self-regulate as a multistructured core rod (MCR) is drawn down into the final hollow core optical fiber structure. This self-regulation provides a core region having a diameter that selected and then stabilized for the duration of the draw process. The inventive process is also useful in controlling the diameter of any selected hollow region of an MCR including, but not limited to, shunts and corner capillaries disposed around the core region.

The present disclosure discloses a polarization-maintaining hollow-core antiresonant fiber. An inner layer of the polarization-maintaining hollow-core antiresonant fiber includes first thin walls, second thin walls, and third thin walls. The present disclosure introduces high birefringence through the wall thickness difference between the first thin wall and the second thin wall, and effectively amplifies a birefringence effect achieved by the wall thickness difference through quasi multi-symmetric structures of the first thin walls and the second thin walls. In addition, the present disclosure reduces the transmission loss and suppresses the leakage of light through the inner layer, particularly, the third thin walls of the inner layer, so that the fiber of the present disclosure realizes polarization maintaining, and meanwhile, reduce the loss as far as possible.