| 摘要 |
PURPOSE: To prevent the image grade from lowering due to temperature change and obtain high-resolution image arrays by a method wherein each single-lens is provided for a plurality of image arrays as one group and, at the same time, the thermal expansion coefficient of board is set to be not more than the specified value and its thermometric conductivity is set within the specified range. CONSTITUTION: A plurality of image arrays correspond to one single-lens 14. Further, by employing board 8 having the thermal expansion coefficient of not more than 10×10<-6> / deg.C, the expansion and contraction of the board 8 is prevented from developing due to temperature change, resulting in enhancing image grade. Furthermore, by using the board 8 having the thermometric conductivity of not more than 1.0×10<-6> m<2> /s, the temperature rise due to the heat transmitted from a neighboring printer and the like and generated in the driving ICs and image arrays of an imaging device is checked, further enhance of image grade is attained. In addition, by using the board 8 having the thermometric conductivity of not less than 0.1×10<-6> m<2> /s, the temperature of the board is prevented from increasing due to the excessive build-up of heat in the board 8. As an above-mentioned result, image grade can be enhanced by making thermal linear expansion coefficient smaller and also by making the change of the temperature of board smaller. |
