Light-emitting device, surface light-emitting apparatus, display system

A light-emitting device, comprising:

• a light-emitting element;
• and
• a lens section covering over the light-emitting element,
• wherein the lens section includes an entrance surface on which light from the light-emitting element is incident;
• an exit surface from which the light incident on the entrance surface is emitted;
• an optical axis extending so as to penetrate through the entrance and exit surfaces;
• a concave section formed in an area of the exit surface, which contains the optical axis;
• and first and second flat sections formed so as to face each other across the optical axis;
• part of the exit surface between the first flat section and the concave section defines a first upwardly-protruding curved surface and part of the exit surface between the second flat section and the concave section defines a second upwardly-protruding curved surface;
• the optical axis is coincident with a reference optical axis of the light-emitting element;
• and
• said first upwardly-protruding curved surface extends from the first flat section to the concave section and said second upwardly-protruding curved surface extends from the second flat section to the concave section.