Light guide device

Provided is a light guide device capable of accurately guiding a light beam controlled by three reflection surfaces to an emission section on the circumferential surface of a light guide plate. The light guide plate (2) is provided with an incident part (4) on the surface facing the plurality of light sources (3), and an exit part (5) on the front peripheral surface. A first reflecting surface (6), a second reflecting surface (7) and a third reflecting surface (8) are arranged on the light guide plate between the incident part and the emergent part; the first reflecting surface reflects the light flux from the incident portion in a first direction opposite to the exit portion, the second reflecting surface reflects the light flux from the first reflecting surface in a second direction intersecting the first direction, and the third reflecting surface reflects the light flux from the second reflecting surface in a third direction toward the exit portion. The second reflection surface includes an inclined surfa