Optical device and illumination device

Abstract

An optical device includes: a light-transmissive member having a first reflective surface configured to reflect, to an arc-shaped first region around a first axis, first light incident along the first axis and having a light distribution characteristic with an optical axis parallel to the first axis; and a reflector having: a second reflective surface and a third reflective surface intersecting each other on the first axis and disposed such that the first reflective surface is located between the second reflective surface and the third reflective surface; and a fourth reflective surface disposed between the second reflective surface and the third reflective surface to reflect the first light to the arc-shaped first region around the first axis.

Dependencies are inferred from the claim text.