| 摘要 |
PURPOSE:To improve information quality by superposing a pulse to the fall of a rectangular pulse, driving a semiconductor laser, adding further pulse light on the trailing end of the rectangular pulse light superposed on DC light and recording and reproducing information. CONSTITUTION:Monostable multivibrators 20, 19 are triggered at the fall of the rectangular pulse by a waveform shaping circuit 17 and the fall of the rectangular pulse past an inverter 18 and a pulse generating circuit 21 is controlled by the outputs from the monostable multivibrators 19, 20. The output from the vibrator 20 is added to the output from the circuit 21 by an adder 22, by which the pulse superposed further with a whisker pulse on the trailing edge of the rectangular pulse is obtd. The semiconductor laser 8 of a current switch part 8 is driven by such pulse, by which the rectangular pulse light is superposed to the DC light. The laser light superposed further with the whisker pulse light on the trailing edge of the rectangular pulse light is obtd., by which the information is recorded and reproduced. The dulled state at the trailing end of the formed bit is shaped and the bit having the good sectional shape is formed. The quality of information is thus improved. |
