| 摘要 |
<p>PURPOSE:To obtain a print of uniform right and left sides by dividing a light emitting diode array provided on a substrate into a plurality of blocks, and providing temperature sensors, heaters and heat sinks at the respective blocks. CONSTITUTION:Temperature sensors 5 provided at respective blocks on a substrate 1 sense the temperatures of the respective blocks. If the sensed temperature is lower than a certain reference temperature A, the heater 7 corresponding to the block is energized through an I/O interface 9 by a microcomputer 10 to heat the block. If any one in the blocks exceeds a reference temperature B, a command is output from the microcomputer 10 which has sensed it through the interface 9 to energize a fan 22 and simultaneously only a heat sink 6 of the block exceeding the temperature B is brought into close contact with the substrate 1 in a heat sink driver 8 to increase a cooling effect, thereby eliminating a temperature difference from other blocks. Accordingly, the light intensities of the diodes become uniform, and qualities of images are made uniform.</p> |
