Abstract: A hollow-core anti-resonant-reflecting fibre (HC-AF) includes a hollow-core region, an inner cladding region, and an outer cladding region. The hollow-core region axially extends along the HC-AF. The inner cladding region includes a plurality of anti-resonant elements (AREs) and surrounds the hollow-core region. The outer cladding region surrounds the inner cladding region. The hollow-core region and the plurality of AREs are configured to provide phase matching of higher order hollow-core modes and ARE modes in a broadband wavelength range.

Abstract: A hollow-core anti-resonant-reflecting fibre (HC-AF) includes a hollow-core region, an inner cladding region, and an outer cladding region. The hollow-core region axially extends along the HC-AF. The inner cladding region includes a plurality of anti-resonant elements (AREs) and surrounds the hollow-core region. The outer cladding region surrounds the inner cladding region. The hollow-core region and the plurality of AREs are configured to provide phase matching of higher order hollow-core modes and ARE modes in a broadband wavelength range.

Abstract: A hollow-core anti-resonant-reflecting fibre (HC-AF) includes a hollow-core region, an inner cladding region, and an outer cladding region. The hollow-core region axially extends along the HC-AF. The inner cladding region includes a plurality of anti-resonant elements (AREs) and surrounds the hollow-core region. The outer cladding region surrounds the inner cladding region. The hollow-core region and the plurality of AREs are configured to provide phase matching of higher order hollow-core modes and ARE modes in a broadband wavelength range.

Abstract: A hollow-core anti-resonant-reflecting fibre (HC-AF) includes a hollow-core region, an inner cladding region, and an outer cladding region. The hollow-core region axially extends along the HC-AF. The inner cladding region includes a plurality of anti-resonant elements (AREs) and surrounds the hollow-core region. The outer cladding region surrounds the inner cladding region. The hollow-core region and the plurality of AREs are configured to provide phase matching of higher order hollow-core modes and ARE modes in a broadband wavelength range.

Abstract: A hollow-core anti-resonant-reflecting fibre (HC-AF) includes a hollow-core region, an inner cladding region, and an outer cladding region. The hollow-core region axially extends along the HC-AF. The inner cladding region includes a plurality of anti-resonant elements (AREs) and surrounds the hollow-core region. The outer cladding region surrounds the inner cladding region. The hollow-core region and the plurality of AREs are configured to provide phase matching of higher order hollow-core modes and ARE modes in a broadband wavelength range.

Abstract: A hollow-core fiber (100) of non-bandgap type comprises a hollow core region (10) axially extending along the hollow-core fiber (100) and having a smallest transverse core dimension (D), wherein the core region (10) is adapted for guiding a transverse fundamental core mode and transverse higher order core modes, and an inner cladding region (20) comprising an arrangement of anti-resonant elements (AREs) (21, 21A, 21B) surrounding the core region (10) along the hollow-core fiber (100), each having a smallest transverse ARE dimension (di) and being adapted for guiding transverse ARE modes, wherein the core region (10) and the AREs (21, 21A, 21B) are configured to provide phase matching of the higher order core modes and the ARE modes and the ARE dimension (di) and the core dimension (D) are selected such that a ratio of the ARE and core dimensions (di/D) is approximated to a quotient of zeros of Bessel functions of first kind (ulm,ARE/ulm,core), multiplied with a fitting factor in a range of 0.9 to 1.

Abstract: A hollow-core fibre (100) of non-bandgap type comprises a hollow core region (10) axially extending along the hollow-core fibre (100) and having a smallest transverse core dimension (D), wherein the core region (10) is adapted for guiding a transverse fundamental core mode and transverse higher order core modes, and an inner cladding region (20) comprising an arrangement of anti-resonant elements (AREs) (21, 21A, 21B) surrounding the core region (10) along the hollow-core fibre (100), each having a smallest transverse ARE dimension (di) and being adapted for guiding transverse ARE modes, wherein the core region (10) and the AREs (21, 21A, 21B) are configured to provide phase matching of the higher order core modes and the ARE modes and the ARE dimension (di) and the core dimension (D) are selected such that a ratio of the ARE and core dimensions (di/D) is approximated to a quotient of zeros of Bessel functions of first kind (ulm,ARE/ulm,core), multiplied with a fitting factor in a range of 0.9 to 1.

Abstract: A new deep blue extended super continuum light source is provided wherein said super continuum at least extends to a low wavelength border ?low low below 480 nm comprising a pump source which operates at a at least one wavelength ?pump and produces pump pulses of a duration (full width half maximum) longer than 0.1 picoseconds with a repetition rate higher than 1 MHz, and a peak power ?peak, and a micro-structured optical transmission medium having at least one wavelength of zero dispersion ?zero, and for the parameters for said pump source exhibiting a second order dispersion parameter ?2, and a non-linear parameter ? arranged so that the optical transmission medium exhibits a modulation instability gain extending to wavelengths above a wavelength ?high?1300 nm and a phase match between ?1ow and a wavelength ?match??high, wherein the pump is adapted to provide energy within the region of anomalous dispersion of the transmission medium.

Abstract: A new deep blue extended super continuum light source is provided wherein said super continuum at least extends to a low wavelength border ?lowlow below 480 nm comprising a pump source which operates at a at least one wavelength ?pumpand produces pump pulses of a duration (full width half maximum) longer than 0.1 picoseconds with a repetition rate higher than 1 MHz, and a peak power ?peak, and a micro-structured optical transmission medium having at least one wavelength of zero dispersion ?zero, and for the parameters for said pump source exhibiting a second order dispersion parameter ?2, and a non-linear parameter ? arranged so that the optical transmission medium exhibits a modulation instability gain extending to wavelengths above a wavelength ?high?1300 nm and a phase match between ?1ow and a wavelength ?match??high, wherein the the pump is adapted to provide energy within the region of anomalous dispersion of the transmission medium.