The invention relates to a mold having an irregularly uneven surface structure in which an average inclination angle is from 20 to 80 degrees; an optical article having an irregularly uneven surface structure in which an average inclination angle is from 20 to 80 degrees; a method for manufacturing an optical article having an irregularly uneven surface structure by transferring an uneven structure of a mold; a transparent substrate for a surface light emitter which uses an optical article having an irregularly uneven surface structure; and a surface light emitter having a transparent substrate for a surface light emitter.