One described aspect is an optical fiber comprising: a fiber core that extends along a fiber axis, is configured to transmit a laser energy along the fiber axis, and terminates at a distal end; a first cladding that extends along the fiber axis, is adjacent to the fiber core, and terminates at a distal end; a coating that extends along the fiber axis and terminates at a distal end, wherein the coating is a gold coating; a second cladding that surrounds a portion of the gold coating along the fiber axis, and terminates at a distal end; an outer jacket that extends along the fiber axis and terminates at a distal end; and a fiber tip. Associated laser systems are also disclosed.

An optical fiber according to an embodiment includes a core and a cladding. The average value n1_ave of the refractive index of the core, the minimum value nc_min of the refractive index of the cladding, and the refractive index n0 of pure silica glass satisfy relationships of n1_ave>nc_min and nc_min<n0. The cladding contains fluorine. The fluorine concentration in the cladding is adjusted to be minimum in the outermost portion of the cladding including the outer peripheral surface of the cladding.

An item such as a fabric-based item may have a layer of fabric such as a layer of woven fabric. The fabric layer may include warp and weft strands. The fabric may cover keys in a keyboard or may be used in forming other structures in the fabric-based item. Each key may have an illuminated key label. Portions of the fabric may be processed by pressing heated protrusions on a textured mold into polymer optical fibers in the fabric. The protrusions form corresponding light-scattering recesses in cladding portions of the optical fibers. Light-emitting diodes or other light sources may be coupled to respective end surfaces of the optical fibers. The light-emitting diodes emit light that is emitted from the thermally imprinted light-emitting regions formed by pressing the heated protrusions into the optical fibers.

Light diffusing optical fibers for use in illumination applications and which have a uniform color gradient that is angularly independent are disclosed herein along with methods for making such fibers. The light diffusing fibers are composed of a silica-based glass core that is coated with a number of layers including both a scattering layer and a phosphor layer.

The invention relates to an optical fiber 1 comprising a core 2 and a cladding 3 surrounding the core 2 and having an outer diameter of 125 m, the optical fiber 1 comprising a cured primary coating 4 directly surrounding the cladding 3 and a cured secondary coating 5 directly surrounding the cured primary coating 4, said cured primary coating 4 having a thickness t.sub.1 between 10 and 18 m and an in-situ tensile modulus Emod.sub.1 between 0.10 and 0.18 MPa, said cured secondary coating 5 having a thickness t.sub.2 between 10 microns and 18 microns and an in-situ tensile modulus Emod.sub.2 between 700 and 1200 MPa, wherein said first and second thicknesses and said first and second in-situ tensile moduli satisfy the following equation:

4%<(t.sub.1t.sub.2E mod.sub.1E mod.sub.2.sup.3)/(t.sub.1_normt.sub.2_normE mod.sub.1_normE mod.sub.2_norm.sup.3)<50%.

A Photonic Crystal Fiber (PCF) a method of its production and a supercontinuum light source comprising such PCF. The PCF has a longitudinal axis and includes a core extending along the length of said longitudinal axis and a cladding region surrounding the core. At least the cladding region includes a plurality of microstructures in the form of inclusions extending along the longitudinal axis of the PCF in at least a microstructured length section. In at least a degradation resistant length section of the microstructured length section the PCF includes hydrogen and/or deuterium. In at least the degradation resistant length section the PCF further includes a main coating surrounding the cladding region, which main coating is hermetic for the hydrogen and/or deuterium at a temperature below T.sub.h, wherein T.sub.h is at least about 50 C., preferably 50 C.<T.sub.h<250 C.

A method for reducing nonlinear frequency shifts and suppressing stimulated Brillouin scattering (SBS) in a fiber laser amplifier system. The method includes providing a seed beam having a certain wavelength and frequency modulating the seed beam with an RF waveform to spectrally broadening the seed beam, where the RF waveform is a relatively slow-speed waveform having a large modulation depth. The method also includes amplifying the frequency modulated seed beam with an amplifier having a large nonlinear phase shift and exhibiting frequency modulation (FM) to amplitude modulation (AM) conversion, where the modulation depth is much larger than the nonlinear phase shift of the amplifier.

Embodiments describe an optical fiber that includes a core. The core has high compressive stress. The compressive stress of the core is in a range of about 20 to 60 MPa. The optical fiber further includes a cladding. The cladding is divided into a first cladding layer and a second cladding layer. The second cladding layer has a high residual stress. The high residual stress of the second cladding layer is in a range of about 20 to 60 MPa. The optical fiber enables reduction of particle related breaks. Further, the optical fiber has elevated LLT strength. The LLT strength is about 6 Kg. The optical fiber has high proof test yield. Furthermore, the optical fiber is highly sensitive to micro-bending of the optical fiber.

The high-density FAU comprises a support substrate having a grooved front-end section that supports glass end sections of the small diameter low-attenuation optical fibers. A cover is disposed on the front-end section and secured thereto to hold the glass end sections in place. The substrate and the cover can be made of the same glass or glasses having about the same CTE. The glass end sections have a diameter d4 so that the pitch P2 of the fibers at the front end of the FAU can be equal to or greater than d4, wherein d4=2r.sub.4, with r.sub.4 being the radius of the glass end section as defined by the optical fiber cladding. The glass end section has a radius r.sub.4 less than 45 microns, allowing for a high-density FAU and a high-density optical interconnection device.

The present disclosure provides a universal optical fiber (100). The universal optical fiber (100) includes a core (102) extended from a central longitudinal axis (110) to a first radius r.sub.1. In addition, the universal optical fiber (100) includes a buffer clad (104) region extending from the first radius r.sub.1 to a second radius r.sub.2. Further, the universal optical fiber (100) includes a trench region (106) extending from the second radius r.sub.2 to a third radius r.sub.3. Furthermore, the universal optical fiber (100) includes a cladding (108) extending from the third radius to a fourth radius r.sub.4. Moreover, the core (102), the buffer clad region (104), the trench region (106) and the cladding (108) are concentrically arranged.