| 摘要 |
PURPOSE:To obtain the information recording of a higher density without hindering the formation of a self-clock signal by executing the many valued recording by the reflected light quantity of pits, etc., for each of the respective pits, giving meaning to the information by the length of the spacings between the respective pits and using this information for data expression as well. CONSTITUTION:The respective recording pits to be recorded on the optical recording medium so as to express plural pieces of the information with one pit are recorded at a specified pit length and the state to permit the recognition at the plural slice levels in the unsatd. state thereof; in addition, the spacings are provided between the respective recording pits and the recording is so executed as to express the plural recording states with the length of the spacings. Namely, the spacing of the specified level (the level which is not the recording state) exists always between the respective recording pits and, therefore, the spacings are made to help form the self-clock signal. The information is expressed in the spacings between the respective recording pits as well by the difference in the spacing length thereof. The spacings are effectively utilized in this way and the sufficient high density recording is attained while the degree of multiplexing is suppressed to a lower level. |
