PROBLEM TO BE SOLVED: To provide an optical device that enables a greater amount of light to be taken out through the optical device even if the optical device is not upsized.SOLUTION: An optical device 10 comprises a first lens 210, a second lens 220, a light guide part 400, and an optical scanning part 100. The first lens 210 and the second lens 220 are positioned on the same optical path as each other. The light guide part 400 has an optical fiber at a tip end, and is positioned on an opposite side to the second lens 220 with the first lens 210 held therebetween in the optical path. The optical scanning part 100 is positioned between the first lens 210 and the second lens 220 in the optical path, and scans with light passing through the optical path. Then, a condensing point, by the first lens 210, of the light made incident on the first lens 210 from the light guide part 400 is positioned between the first lens 210 and the second lens 220.
