| 摘要 |
PROBLEM TO BE SOLVED: To provide a document illuminating device capable of setting a positional relationship between a light source and a light guide body to a predetermined positional relationship to improve light efficiency by using a holding member integrally holding the light source and the light guide body, and suppressing light from entering to an immobilizing member to improve light efficiency; and an image reading device.SOLUTION: A document illuminating device illuminates a line-like document image area elongated in a longitudinal direction with light from a light source for scanning to read a document image, and has an incident surface provided opposite to the light source, a light guide body that transmits and internally reflects the light from the light source to introduce the light to an emission surface, and a holding member that holds the light source, and also the light guide body with an immobilizing member therebetween. The document illuminating device inclines a surface normal direction of the incident surface or a direction in which the immobilizing member is mounted on the holding member relatively to a surface normal direction of the emission surface of the light source or a maximum strength direction of a light radiation angle, so as to deflect a light beam in the maximum strength direction made incident on the incident surface in a direction separated from the immobilizing member. |
