Light source unit for projection type display apparatus

A projection-type display apparatus comprising:

• a light source unit;
• an image generation optical system that generates image light, by modulating light from the light source unit on a basis of an inputted image signal;
• and
• a projection optical system that projects the image light generated by the image generation optical system, wherein
• the light source unit includes:
• a base member having one face and another face that face each other, and having a first region and a second region that are disposed side by side,
• a first light-emitting element group disposed in the first region of the one face,
• a second light-emitting element group disposed in the second region of the one face, and having substantially the same heat generation amount as the first light-emitting element group,
• a first heat dissipation structure provided in the first region on an upstream side, and
• a second heat dissipation structure provided in the second region on a downstream side, and having a heat dissipation characteristic greater than a heat dissipation characteristic of the first heat dissipation structure,
• wherein each of the first heat dissipation structure and the second heat dissipation structure is configured by a plurality of fins disposed on the other face of the base member,
• wherein a plurality of holes are provided on both the first heat dissipation structure and the second heat dissipation structure such that a density of the plurality of holes increases from the upstream side to the downstream side, and
• wherein the plurality of fins structuring the second heat dissipation structure is disposed more densely than the plurality of fins structuring the first heat dissipation structure.