The company can provide F4GT and other glass rods for optical fiber. The glass has excellent properties such as high transmittance, high uniformity and good internal quality. It is mainly used to produce the optical fiber image bundle in “rod in tube method”. Each optical fiber in the image bundle transfers a pixel, which corresponds to the output geometrically. It can transmit the image accurately in any bending state and is widely used in industrial, medical, electrical, military, chemical and other fields, such as fiber optic endoscope, military night vision sighting equipment, fingerprint identification module and other fields.