| 摘要 |
PURPOSE:To provide a semiconductor-laser driver circuit, in which a noise level is reduced. CONSTITUTION:In a semiconductor-laser driver circuit light-emitting and driving a semiconductor laser by a driving signal, in which a high--frequency signal A1 is overlapped to an input signal, said high-frequency signal A1 is formed in a rectangular wave signal, and optical output power B1 can be formed in a rectangular wave shape by overlapping the high-frequency rectangular wave signal Al to the input signal, thus making the peak value of the optical output power B1 lower (l//2Pmax) than that (Pmax) at the time of a sine wave shape. Consequently, allowance up to the rated power limit Pmax of the semiconductor laser is extended so much, and the high-frequency level of the high-frequency signal can be made larger than that at the time of the sine wave shape. Accordingly, the spot diameter of laser beams is reduced, and a noise level can be made lower than that at the time of the sine wave shape. Allowance up to rated power is extended, thus allowing the overlapping of the high-frequency signal even at the time of lighting and at the time of erasing. |
