| 摘要 |
<P>PROBLEM TO BE SOLVED: To reduce the influence of thermal interference without causing increase of the size. <P>SOLUTION: When 40 light emitting parts (ch1 to ch40) are orthogonally projected on virtual lines extending in an S direction corresponding to a sub-scanning direction, each of the light emitting part ch1 to the light emitting part ch20 has an equal distance 2c to the adjacent part, each of the light emitting part ch20 to the light emitting part ch21 has a distance 3c from each other, and each of the light emitting part ch21 to the light emitting part ch40 has an equal distance 2c to the adjacent part, wherein c is a predetermined value. As a result, without increasing the size not so much, the distances between the light emitting parts which are in the region largely affected by other light emitting parts can be widened. Therefore, without increasing the size, the influence of thermal interference can be reduced than conventional cases. <P>COPYRIGHT: (C)2009,JPO&INPIT |
