| 摘要 |
PURPOSE:To facilitate superior pit recording with the use of a low power laser by generating a digital signal in which the width of H-level is extended is extended as required, dividing the H-level of this signal to plural variable sections, and making the signal in a specified variable section formed with H,L-levels to a recording signal. CONSTITUTION:A digital recording signal A in which the H-level corresponding to the pit is the integral multiple of a reference clock CP, becomes a signal B in which the H-level is extended in the period of clock CP by a shift register 1 and an OR circuit 5. On the other hand, a clock CK by which the clock CP is divided to eight, is counted by hexadesimal binary counters 3, 4, and the signal B is divided to plural variable sections through an AND gate 6, NOT circuit 9 and AND gate 7, then also made to the H,L-signals of the section corresponding to the H-level of signal A, and a laser 11 is driven by a recording signal E formed with the H, L-levels through an FF 2. By the constitution using these H,L signals, the superior pit recording can be performed with the use of low power laser. |
