Patent ID: 9568730
Date: 2017-02-14
CPC Classifications: G02B

Claim:
1. An optical device comprising: a light guide including an inside portion disposed between a first face and a second face, the second face being disposed at an opposite side of the inside portion to the first face; a first diffraction element that is a transmission type diffraction element provided on a first face of the light guide and that diffracts and emits at least a portion of light which is guided along the inside portion of the light guide; a second diffraction element that is a transmission type diffraction element provided on the first face of the light guide and that diffracts at least the first portion of light which enters the inside portion of the light guide; and a third diffraction element that is a reflection type diffraction element provided on the second face of the light guide, and that diffracts at least a second portion of the light which enters the inside portion of the light guide via the second diffraction element, wherein