PRISM GROUP AND PROJECTION APPARATUS

Abstract

A prism group including a first, a second, and a third prisms is provided. The first prism has a first light incidence surface, a first light emitting surface, and a first connecting surface. The second prism has a second light incidence surface, a second light emitting surface, and a second connecting surface. The second light incidence surface is located between the first light emitting surface and the second light emitting surface. A first air gap is between the second light incidence surface and the first light emitting surface. The third prism has a third light incidence surface, a third light emitting surface, and a third connecting surface. The third light incidence surface is located between the second light emitting surface and the third light emitting surface. A second air gap is between the third light incidence surface and the second light emitting surface. A projection apparatus is also provided.