Patent ID: 8146389

Claim:
A method of making a fiber having a core and a cladding, wherein the fiber can be used as a light source, optical amplifier and timeable laser, the method comprising the steps of: (a) providing a source material selected from the group consisting of crystal, glass having garnet structure and ceramic; (b) putting the source material into a laser heated system provided with an annular laser beam; (c) forming the core from the source material in the laser heated system forming the core by (i) disposing the source material in a laser heated pedestal growth apparatus, (ii) melting a tip of the source material with an annular laser beam to form a molten zone at the tip, (iii) dipping a seed crystal into the molten zone, and (iv) pulling the seed crystal away from the molten zone to form the core at the bottom of the seed crystal; (d) inserting the core into a hollow glass tube; and (e) heating the core and the hollow glass tube by co-feeding the hollow glass tube with inserted core in the same feed direction in the laser heated system and causing the annular laser beam to be applied to the co-fed hollow glass tube with inserted core at the hollow glass tube so as to heat the hollow glass tube and core together and thereby to form the fiber by welding and ion diffusion.