Optical device and display apparatus

A display apparatus, comprising:

• an optical device including a substrate, a first end being a light-outgoing end, and a second end arranged at a side opposite to the first end;
• and
• an image generation unit capable of two-dimensionally scanning light outgoing from the optical device and controlling brightness of projected light on a basis of image data,
• the optical device including
• a stripe-shaped first electrode layer extending from the second end to the first end,
• a first conduction type layer including a current injection region formed by the first electrode layer and a current non-injection region,
• a second conduction type layer arranged on the substrate,
• an active layer arranged between the first conduction type layer and the second conduction type layer, and
• a second electrode layer being in contact with the substrate or the second conduction type layer,
• the first conduction type layer, the active layer, and the second conduction type layer including a waveguide structure, the waveguide structure including
• a first region having a first waveguide that is the current injection region and the current non-injection region and having a first refractive index difference between a refractive index of the current injection region and a refractive index of the current non-injection region, and
• a second region arranged between the first region and the first end having a second waveguide arranged to be extended from the first waveguide to the first end and having a second refractive index difference between a refractive index of the second waveguide and a refractive index of a region around the second waveguide in the second region, the second refractive index difference being greater than the first refractive index difference,
• the second waveguide having a reflection structure that reflects light entered from the first waveguide and slopes an optical axis and a taper structure that decreases a size of a beam spot of light entered from the reflection structure.