| 摘要 |
PROBLEM TO BE SOLVED: To provide an illuminating device capable of reducing loss of light at the entry to a light guide body to efficiently illuminate an illumination place, an image reading device, and an image forming apparatus.SOLUTION: An incident surface 903a, a second emitting surface 903d, and a reflection member 904 are arranged on an optical axis of a light source 901; and the incident surface 903a has a planar shape to be substantially orthogonal to the optical axis. A first emitting surface 903c and a reflection surface 903b are arranged respectively on both end sides located across the optical axis of the light source 901; and the reflection surface 903b has a curved shape formed in an outward convex shape to guide a part of the light from the light source 901 except the optical axis to the first emitting surface 903c. |
