Horizontal extension device of optical fiber preform

The utility model relates to a horizontal extension device for a single mode fiber preform, which leads major diameter preforms to extend to be minor diameter preforms, and comprises a left side chuck, a right side extension chuck, diameter measurement meters, a high temperature furnace and a controller. The left side chuck is arranged on the left side of the high temperature furnace, and the right side extension chuck is arranged on the right side of the high temperature furnace. The diameter measurement meters are arranged on two sides of a base metal of the preform and connected with the controller through wires, and the controller is connected with the right side extension chuck through controlling wires. The base metal of the preform is grasped by the preform feeding chuck arranged on the left side driving portion and the extension chuck arranged on the right side driving portion, the diameter measurement meters are used for measuring an actual diameter of the preform and recording positions of the preform when each external diameter is measured, extension is started when a heated portion of the preform base metal is in a state of fusion caused by the high temperature furnace, the controller is used for controlling speed of the extension chuck, and then controlling the diameter of the preform after the preform is extended, thereby leading a fact that the diameter of the preform of the base metal is very close to a target diameter.