Abstract:
An optical fiber comprises a silica multimode optical core having a refractive index n1 and at least one polymer optical cladding having a refractive index n2, with n1>n2. It further comprises a heterogeneous polymer intermediate optical cladding situated between the multimode core and the optical cladding and having a refractive index substantially equal to the refractive index n1 of the multimode core.
Abstract:
An optical fiber amplifier is considered comprising a mono-mode core, a first cladding around said core and at least a further cladding around said first cladding while said first cladding includes a ring shaped active region doped with rare earth material surrounding said mono-mode core. Advantageously, the first cladding is designed with a radial refractive index following an almost continuous decreasing function for increasing radius. The use of a continuously decreasing refractive index for the cladding at the outer border of the ring shaped active medium optimize the efficiency of the coupling between the core and the cladding.
Abstract:
A fiber amplifier comprises an amplifying double-clad fiber (DCF). The fiber has a core having a first refractive index, an inner cladding surrounding the core and having a second refractive index lower than the first refractive index and an outer cladding surrounding the inner cladding. The core is doped with Erbium (Er) and co-doped with Ytterbium (Yb), and further co-doped with Cerium (Ce). The Ytterbium (Yb) enables pump energy transfer from Ytterbium (Yb) ions being in the excited state to Erbium (Er) ions being in the ground state (4I15/2). The Cerium enables a resonant energy transfer between the Erbium (Er) excited state (4I11/2) and Cerium (Ce) ground state (4F7/2). This leads to a lower population of the Erbium 4I11/2 state and thereby increases energy transfer from Ytterbium to Erbium.
Abstract:
The invention relates to an optical fiber amplifier (OFA) having a controllable heating system for adjusting and stabilizing the temperature of a fiber, wherein the heating system comprises a heat-generating fiber coating (TC) that has an electrical connection for applying a heating voltage or injecting a heating current (I1, I2) for the purpose of heat generation, wherein the heat-generating fiber coating (TC) surrounds at least a part of the fiber (OF), and also a method therefor.
Abstract:
The object of the present invention is to design a photonic crystal fiber with high birefringence property such to preserve the polarization of optical signals transmitted through such fiber without implying to high manufacturing cost. For that a photonic crystal fiber is designed having at least the inner rows of the used longitudinal holes surrounding its guiding core following a parallelogram shape arrangement. This leads to a photonic crystal with an at most two fold rotational symmetry about a longitudinal symmetry. It is a particularly advantageous way to introduce a high birefringence which will guarantee to retain the polarisation of the transmitted optical signals.
Abstract:
An optical fiber with microstructures comprises a plurality of capillary tubes disposed around a central rod and including a self-cleaning layer including molecules able to react with hydroxyl molecules to produce volatile gaseous substances.
Abstract:
The present invention concerns an optical guide (100) comprising an amplifier medium including: a core (10) in a main matrix of a transparent material, the main matrix containing particules (1, 2), each particule being formed of a submicronic matrix distinct from the main matrix and doped by an active metal element, an external guiding cladding (11) in contact with the core (10). The size of the particules (1, 2) is smaller than 20 nm. The present invention also concerns a method for producing this guide.