An improved art of producing an optical recording medium by utilizing a photo-etching technique is disclosed. Pits pattern of address for guide groove and sector on each of tracks of optical recording medium to be preformatted is formed in accordance with a photo-etching process or a resist lift-off...http://www.google.com/patents/US4877713?utm_source=gb-gplus-sharePatent US4877713 - Preformatted optical recording card and method of producing the same
