The invention belongs to the technical field of
optical fiber manufacturing, and particularly discloses a preparation method of a taper-
core optical fiber with a gradually-changed core-to-
package ratio and the taper-
core optical fiber. The method comprises the following steps: depositing a
glass particle loose layer on the inner wall of a
reaction tube; performing
rare earth ion doping on the
glass particle loose layer;
drying the
reaction tube, conducting
sintering at high temperature, so as to vitrify the
glass particle loose layer, conducting fusing to form a
solid preform core rod, and then
polishing the
solid preform core rod to obtain a conical core rod with a specified taper angle; and conducting
processing to obtain a cylindrical glass rod which is provided with a conical hollow hole, combining the glass rod with the conical hollow hole with a conical core rod to obtain a conical core active
optical fiber preform, and putting the conical core active
optical fiber preform into a
wire drawing tower for drawing to obtain the conical
core optical fiber with a gradually changed core-to-cladding ratio. The taper core optical
fiber is prepared by the method. The core-to-
package ratio of the prepared taper core optical
fiber with the gradually-changed core-to-
package ratio is gradually changed along with the length of the optical
fiber, pump light absorption of the optical fiber can be improved, optical fiber heat production can be balanced, and
laser output power can be improved.