A planar light source, Fresnel lens sheet, and louver are disposed in the stated order in a light source apparatus. The Fresnel lens sheet deflects and focuses in one dimension light that has entered from the planar light source. The louver is disposed in the optical path of the light emitted from the Fresnel lens sheet, and the directivity of the light can be increased by restricting the traveling direction of the light to the focal direction of the Fresnel lens sheet. The light utilization ratio can thereby be increased, the directivity of planarly emitted light can be increased, and the brightness can be made uniform at the point of observation.