| 摘要 |
PURPOSE:To reproduce the intermediate tone of facsimile signal with fidelity, by converting the reception video signal including the intermediate tone into the pulse train having the width corresponding to the level. CONSTITUTION:The system consists of the detection circuit 1 and the oscillation circuit 2 oscillating triangle waves having higher frequency than the specified maximum video frequency. Further, the detection output 1' makes level change in response to white and black of original; low level L corresponds to white, high level H to black, and changed part of intermediate level to the intermediate tone. At the area where the oscillation output 2' is not exceeded negative from the detection output 1', the compared output 3' is VEE. When the part in excess of negative part is caused, the output 3' momentarily increases to Vcc to keep Vcc for the period in excess of it. The more the output 1' goes to the level H, the longer is the period in excess of negative side of the triangle waves 2' developed one after another and the longer is the pulse width of the output 3'. This output 3' indicates intermediate tone and it the pulse train having the width corresponding to the change in the intermediate level of the output 1'. If the output 2' does not exceed the output 1', the output 3' is fixed to Vcc. By applying the output 3' like this to the recording electrode, the size of nozzle spattered particles of ink jet system changes correspondingly. |
