Illumination apparatus, image sensor unit and image reading apparatus

An image sensor unit comprising:

• an illumination apparatus;
• an image sensor that converts light from an object of illumination to an electric signal;
• and
• a sensor substrate on which the image sensor is mounted,
• wherein:
• the illumination apparatus comprises:
• a light source;
• a rod-like light guide having an incident surface that enters light from the light source that is disposed on one side in a main-scan direction, a diffusing surface that diffuses light that enters from the incident surface, and an emission surface that linearly emits light towards an object of illumination;
• and
• a reflection member having a reflection surface that reflects light that is diffused by the diffusing surface to the light guide,
• the light guide has a locking projection that is locked in the reflection member on the one side in the main-scan direction,
• the reflection member has a locking hole in which the locking projection is locked, and
• a cut-out portion at which one part is cut out is formed in the locking hole.

An image reading apparatus comprising:

• an image sensor unit having an illumination apparatus, an image sensor that converts light from an object of illumination to an electric signal, and a sensor substrate on which the image sensor is mounted;
• and
• a transport portion that relatively transports the image sensor unit and the object of illumination,
• wherein:
• the illumination apparatus comprises:
• a light source;
• a rod-like light guide having an incident surface that enters light from the light source that is disposed on one side in a main-scan direction, a diffusing surface that diffuses light that enters from the incident surface, and an emission surface that linearly emits light towards the object of illumination;
• and
• a reflection member having a reflection surface that reflects light that is diffused by the diffusing surface to the light guide,
• the light guide has a locking projection that is locked in the reflection member on the one side in the main-scan direction,
• the reflection member has a locking hole in which the locking projection is locked, and
• a cut-out portion at which one part is cut out is formed in the locking hole.