| 摘要 |
<p>PURPOSE:To prevent a contrast from decreasing, and to enhance resolution by providing a light quantity correcting circuit, and controlling the quantity of emitting light of each light emitting diode in response to a space frequency having a light emitting pattern. CONSTITUTION:A driving circuit 19 pattern-controls ON, OFF of a light emitting diode row 10 in response to an input signal to so drive an operation current controller 18 as to emit a light from the row 10. In this case, a light quantity correcting circuit 20 extracts printing data by a print pattern extracting circuit 201 from the input signal, generates a control signal for correcting point data A(n) according to a correction control rule 203 together with print data A(n) to be corrected and K pieces of print data A(n-K), A(n-K+1),..., A(n+k-1), A(n+K) before and after the data A(n) through a shift register 202, and controls the controller 18 to control the emitting light amount of each diode 101, thereby suppressing the decrease in the contrast ratio. Accordingly, it can suppress the decrease in the contrast due to the difference of the printing patterns, and realize to enhance the resolution of a printer.</p> |
