A light source apparatus includes a light source, a light collection optical system configured to collect a pencil of light emitted from the light source using multiple lenses, a microlens array formed into a size corresponding to a collected light diameter of a pencil of light collected by the light collection optical system and caused to be incident thereon from the light collection optical system, and a display device on to which light transmitted through the microlens array to be superimposed together is incident.