NKT PHOTONICS A/S

A hollow core photonic crystal fiber (PCF) including an outer cladding region and seven hollow tubes surrounded by the outer cladding region. Each of the hollow tubes is fused to the outer cladding to form a ring defining an inner cladding region and a hollow core region surrounded by the inner cladding region. The hollow tubes are not touching each other but are arranged with distance to adjacent hollow tubes. The hollow tubes each have an average outer diameter d 2 and an average inner diameter dl, wherein d 1 /d 2 is equal to or larger than about 0.8. Also, a laser system.

A microstructured optical fiber including a core region and a cladding region which surrounds the core region. The cladding region includes a plurality of cladding features within a cladding background material, wherein the cladding region includes an inner cladding region with at least one inner ring of cladding features and an outer cladding region with at least three outer cladding rings of outer cladding features. The inner cladding features have a first characteristic diameter and the outer cladding region includes a plurality of outer cladding features having a characteristic diameter smaller than the first characteristic diameter. The first characteristic diameter is at least about 10% larger than an average diameter of the outer cladding features and the core region has a diameter of at least about 2 μm. A cascade optical fiber with at least one fiber as described, as well as a source of optical supercontinuum generation.

A hollow core photonic crystal fiber (PCF) including an outer cladding region and seven hollow tubes surrounded by the outer cladding region. Each of the hollow tubes is fused to the outer cladding to form a ring defining an inner cladding region and a hollow core region surrounded by the inner cladding region. The hollow tubes are not touching each other but are arranged with distance to adjacent hollow tubes. The hollow tubes each have an average outer diameter d2 and an average inner diameter d1, wherein d1/d2 is equal to or larger than about 0.8, such as equal to or larger than about 0.85, such as equal to or larger than about 0.9. Also, a laser system.

An optical fiber for guiding an optical signal, the optical fiber includes: a core region; a cladding region surrounding the core region, the cladding region including an inner cladding region and an outer cladding region, wherein a plurality of the plurality of inner cladding features are of a first type of feature, wherein a plurality of the plurality of inner cladding features are of a second type of feature including an air hole in direct contact with the background material having a refractive index, n b , and wherein the inner cladding features are arranged in a substantially hexagonal lattice and the six nearest neighbors surrounding a first type of feature are of the second type of feature, and wherein no first type of feature is surrounded by less than six nearest neighbors of the second type of feature.

A hollow core photonic crystal fiber (PCF) including an outer cladding region and seven hollow tubes surrounded by the outer cladding region. Each of the hollow tubes is fused to the outer cladding to form a ring defining an inner cladding region and a hollow core region surrounded by the inner cladding region. The hollow tubes are not touching each other but are arranged with distance to adjacent hollow tubes. The hollow tubes each have an average outer diameter d 2 and an average inner diameter d 1, wherein d 1/ d 2 is equal to or larger than about 0.8, such as equal to or larger than about 0.85, such as equal to or larger than about 0.9. Also, a laser system.

A hollow core photonic crystal fiber (PCF) including an outer cladding region and seven hollow tubes surrounded by the outer cladding region. Each of the hollow tubes is fused to the outer cladding to form a ring defining an inner cladding region and a hollow core region surrounded by the inner cladding region. The hollow tubes are not touching each other but are arranged with distance to adjacent hollow tubes. The hollow tubes each have an average outer diameter d 2 and an average inner diameter d 1, wherein d 1/ d 2 is equal to or larger than about 0.8, such as equal to or larger than about 0.85, such as equal to or larger than about 0.9. Also, a laser system.

A microstructured optical fiber including a core region and a cladding region which surrounds the core region. The cladding region includes a plurality of cladding features within a cladding background material, wherein the cladding region includes an inner cladding region with at least one inner ring of cladding features and an outer cladding region with at least three outer cladding rings of outer cladding features. The inner cladding features have a first characteristic diameter and the outer cladding region includes a plurality of outer cladding features having a characteristic diameter smaller than the first characteristic diameter. The first characteristic diameter is at least about 10% larger than an average diameter of the outer cladding features and the core region has a diameter of at least about 2 μm. A cascade optical fiber with at least one fiber as described, as well as a source of optical supercontinuum generation.

A microstructured optical fiber having a length and a longitudinal axis along its length, the finer including a core region capable of guiding light along the longitudinal axis and a cladding region which surrounds the core region, the cladding region comprising a cladding background material and a plurality of cladding features within the cladding background material, the cladding features being arranged around the core region, wherein the cladding region comprises an inner cladding region comprising an innermost ring of cladding features and an outer cladding region comprises outer cladding rings of outer cladding features, the innermost ring consisting of those cladding features being closest to the core region, wherein the rings of cladding features each comprise bridges of cladding background material separating adjacent features of the ring, wherein the bridges of the innermost ring have an average minimum width (w1), the minimum width of a bridge of a ring being the shortest distance between two adjacent features of the ring; and wherein at least one outer cladding ring has an average minimum width (w2) of bridges that is larger than the average minimum width (w1) of the bridges of the innermost ring. Also described are a cascade optical fiber with at least one fiber as described, as well as a source of supercontinuum radiation.

A hollow core photonic crystal fiber (PCF) including an outer cladding region and seven hollow tubes surrounded by the outer cladding region. Each of the hollow tubes is fused to the outer cladding to form a ring defining an inner cladding region and a hollow core region surrounded by the inner cladding region. The hollow tubes are not touching each other, but are arranged with distance to adjacent hollow tubes. The hollow tubes each have an average outer diameter d 2 and an average inner diameter d 1 , wherein d 1 /d 2 is equal to or larger than about 0.8, such as equal to or larger than about 0.85, such as equal to or larger than about 0.9. Also, a laser system.

A microstructured optical fiber having a length and a longitudinal axis along its length, the finer including a core region capable of guiding light along the longitudinal axis and a cladding region which surrounds the core region, the cladding region comprising a cladding background material and a plurality of cladding features within the cladding background material, the cladding features being arranged around the core region, wherein the cladding region comprises an inner cladding region comprising an innermost ring of cladding features and an outer cladding region comprises outer cladding rings of outer cladding features, the innermost ring consisting of those cladding features being closest to the core region, wherein the rings of cladding features each comprise bridges of cladding background material separating adjacent features of the ring, wherein the bridges of the innermost ring have an average minimum width (w 1 ), the minimum width of a bridge of a ring being the shortest distance between two adjacent features of the ring; and wherein at least one outer cladding ring has an average minimum width (w 2 ) of bridges that is larger than the average minimum width (w 1 ) of the bridges of the innermost ring. Also described are a cascade optical fiber with at least one fiber as described, as well as a source of supercontinuum radiation.