Abstract: The present invention relates to an optical fiber (100, 200, 300, 400) comprising one or more cores (102), a clad enveloping the one or more cores and a buffer clad layer (202, 302, 402) between the first clad layer and the second clad layer. Particularly, the clad includes a first clad layer (104) is made of silica with less than 0.1% metallic impurity and a second clad layer (106) is made of silica with greater than 0.1% of metallic impurity. Further, the first clad layer has less than 800 ppm OH content, less than 10 ppm aluminium and less than 2 ppm sodium and the second clad layer has less than 50 ppm OH content, more than 10 ppm aluminium and more than 2 ppm sodium.

Abstract: Disclosed is a multi-core optical fiber having a plurality of cores extending parallelly along a central axis of the multi-core optical fiber. Each core of the plurality of cores is up-doped with an up-dopant. The multi-core optical fiber further has a plurality of buffer layers such that each buffer layer of the plurality of buffer layers envelop a corresponding core of the plurality of cores. Each buffer layer of the plurality of buffer layers has a predefined buffer layer thickness. The multi-core optical fiber further has a plurality of trench layers such that each trench layer of the plurality of trench layers envelops a corresponding buffer layer of the plurality of buffer layers. Each trench layer of the plurality of trench layers is down-doped with a down-dopant. The multi-core optical fiber has an inter-core crosstalk of less than ?30 decibel/kilometres (dB/km) at a wavelength of 1550 nanometres (nm).

Abstract: The present disclosure provides a multi-core fiber (MCF) and manufacturing method thereof and an MCF marker (or marker). The MCF (100) comprises a plurality of cores (102) and a marker (108). Each core is associated with a core diameter (104) and a core-placement-radius (106) and the marker (108) is associated with a marker diameter (110) and a marker-placement-radius (112). The marker has a marker core (116) and a marker clad (118) with a D/d ratio between 5 to 20. During manufacturing, the MCF is drawn from a preform assembly (200) having a top hollow handle (202) with a handle thickness (114) attached on a top end of a glass preform (204) that has a plurality of core holes (206) and a marker hole (210), wherein the marker hole (210) is at least partially covered by the top hollow handle of the handle thickness (114).

Abstract: The present invention relates to a preform assembly and a method for drawing a multicore optical fibre and a holey fibre. Particularly, the preform assembly includes a hollow cylindrical tube, a plurality of discs stacked inside the hollow cylindrical tube and a plurality of core rods inserted in a plurality of through holes in each of the plurality of discs.

Abstract: The present disclosure provides a system for generating fumed silica particles for manufacturing of an optical fiber preform. The system includes a generator and a plurality of inlets connected with the generator. The generator includes a plurality of burners. The plurality of inlets include a first inlet, a second inlet, a third inlet and a fourth inlet. The first inlet provides passage for flow of a precursor material to the generator. The second inlet provides passage for flow of a first gas to the generator. The third inlet provides passage for flow of a second gas to the generator. The fourth inlet provides passage for flow of a carrier gas to the generator. The plurality of burners enables a chemical reaction between the precursor material, the first gas and the second gas that facilitates the generation of the fumed silica particles.