PURPOSE: To provide the image fiber having a small diameter and high strength.
CONSTITUTION: TiO2-SiO2 glass is used for a jacket 2 constituting the image fiber 1. Since the TiO2-SiO2 glass has the high mechanical strength, the formation of the image fiber to a small diameter is possible and such image fiber is particularly adequate to medical purposes. This image fiber is produced by a method of forming porous glass consisting of the TiO2-SiO2 glass by a VAD method, then vitrifying this glass to transparent glass and boring a hole at its center by an ultrasonic boring method. Many optical fibers are packed into the resulted TiO2-SiO2 glass tube to form an image fiber preform. This image fiber preform is drawn from its one end, by which the image fiber is formed.
KANEDA KEIJI
SHAMOTO NAOKI
TSUMANUMA KOUJI
SANADA KAZUO
