A light source device including a light guide plate (13) and a light source. The light guide plate (13) has: an incident surface on which light emitted from the light source is incident; an emission surface that emits light incident from the incident surface; and a propagation/reflection surface that faces the emission surface and propagates and reflects the light incident from the incident surface, towards the emission surface. The propagation/reflection surface has substantially V-shaped grooves, and the substantially V-shaped grooves comprise at least two types of grooves.
