Light-emitting device and lighting device

A light-emitting device, comprising:

• a light source comprising a light-emitting element, the light source having an optical axis extending in a first direction;
• and
• an optical element having a surface including
• an incident region on which light emitted from the light source is incident,
• a first region positioned at a side opposite to the incident region, the first region being larger than the light-emitting element when viewed in the first direction,
• the first region configured to reflect, toward the light source, a first light entering the optical element through the incident region,
• the first region configured to reflect, toward the light source:
• a portion of the first light that reaches a central region of the first region, the central region overlapping the light-emitting element when viewed in the first direction, and
• a portion of the first light that reaches an outer region of the first region positioned outward of the central region,
• a ring-shaped second region surrounding the first region, the second region being configured to reflect a second light entering the optical element through the incident region, and
• a ring-shaped third region surrounding the incident region, the third region configured to reflect, toward the second region, the second light that is reflected by the second region, wherein
• the optical element is configured such that:
• light that is reflected by the third region is emitted from the second region, and
• each of the first light and the second light includes the light emitted from the light source and a third light, which is reflected by the light source after being reflected by the first region,
• each of a first cross section of the third region and a cross section of the third region parallel to the first cross section is a polygonal line made by connecting a plurality of line segments, the first cross section including a first axis and one second axis orthogonal to the first axis, the first axis being the optical axis of the light source, and
• each of a second cross section of the third region and a cross section of the third region parallel to the second cross section is a continuous curve, the second cross section including the first axis and a third axis, the third axis being orthogonal to the first and second axes.