| 摘要 |
PURPOSE:To carry out easily the recording of an information signal by the difference in the shape of the cross section of laser beams respectively for recording and erasing by arranging alternately a strip part having high heat conductivity and a strip part having low heat conductivity, and regulating the heat conductivity of each part. CONSTITUTION:Strip crystalline parts 3, 3, 3, etc. extending in the extending direction of recording tracks and strip amorphous parts 4, 4, 4, etc. are alternately arranged in parallel in the direction as shown by the arrow Y which crosses vertically the extending direction of recording tracks to form a recording layer 2. The shape of the cross section which is highly modulated by the information signal to be recorded is rapidly heated and cooled by a circular laser beam to form amorphous parts S, S, etc.at the crystalline parts 3 and 3, and the recorded contents of the recording layer 2 are erased by slowly heating or cooling the amorphous parts S, S, S, etc. to change the amorphous state into the crystalline state. |
