Strong, fatigue-resistant optical fiber with enhanced side irradiation

A method for manufacturing an optical fiber comprising:

• an outer cladding section surrounding an inner core section, the outer cladding section having a refractive index lower than the refractive index of the core section and the outer cladding section and the core section forming an optical light guide;
• an emission area associated with one emission end of the optical fiber, the emission area extending in the direction of a longitudinal axis along the optical fiber and being arranged for emitting radiation in a lateral direction with respect to the longitudinal axis of the optical fiber;
• wherein within the emission area, the core section is provided with a plurality of scattering sites, which are each formed by a local variation of the refractive index in the core section
• the method comprising the acts:
• creating the scattering sites by focusing femtosecond laser pulses at the intended scattering sites.