Optical apparatus, light source apparatus, and vehicle

An optical apparatus, comprising:

• a plurality of semiconductor laser elements each of which emits laser light;
• a light guide member which has a light guide section which guides the laser light;
• and
• an imaging section which causes the laser light of each of the plurality of semiconductor laser elements to form an image on an incidence end surface of the single light guide section,
• the incidence end surface having an outer shape which has a first side defining a width of the light guide section and a second side defining a height of the light guide section,
• a plurality of spots which are formed on the incidence end surface and correspond to the plurality of semiconductor laser elements having respective long axes which are aligned with each other,
• the long axes of the plurality of spots being aligned with the first side or the second side of the incidence end surface.