| 摘要 |
<p>PROBLEM TO BE SOLVED: To obtain an LED print head being employed for writing an image in electrophotographic process in which fluctuation in the quantity of light can be corrected for each dot while controlling gradation without sacrifice of print speed. SOLUTION: The LED 6 for each dot in an LED print head is driven with the total output current of a main transistor 4 for writing and a subtransistor 5 for correction. Drive current is controlled by turning the subtransistor 5 on only during on time of the main transistor 4 thus correcting fluctuation in the quantity of light of the LED 6 while controlling gradation.</p> |
