Abstract: An electrophotographing method for use in a copying apparatus employing a sensitizing screen having a great number of fine apertures, made in a drum shape, and a transferring means having a conductive base plate and a charge storage layer formed on the base plate. The transferring means is constructed in the form of a drum. During the process of obtaining a great number of copies from a primary electrostatic latent image which has been stored on the sensitizing means, a secondary electrostatic latent image is formed and regenerated on the transferring means from the stored primary latent image.

Abstract: An optical fiber bundle having end portions where respective fibers are fixed together and a middle portion where respective fibers are separated from each other and provided with reinforcing pipes covering portions near border lines between said middle portion and said end portions, portions near end portions of said optical fiber bundle having high strength against bending.

Abstract: A treating method for giving durability to an optical fiber bundle produced by bundling optical fibers respectively covered by acid-soluble glass, shielding both end portions thereof by acid-resisting material and dissolving and removing said acid-soluble glass at the middle portion by means of acid. That is, said optical fiber bundle is immersed in organic solvent containing antifriction agent and is subjected to ultrasonic oscillation for the purpose of removing sludge remaining in said optical fiber bundle and replacing said sludge with said antifriction agent.