PROJECTION DISPLAY DEVICE

A projection display apparatus is provided, including an optical machine module (1). The optical machine module (1) includes a light emitting module (11) and a modulation module (12). The light emitting module (11) includes a light source (111) configured to emit linearly polarized light. The modulation module (12) includes a modulation component. The modulation component includes a light-combining prism (122a) and an LCOS modulator. The light-combining prism (122a) includes four rectangular prisms. The light-combining prism (122a) has four sides and four intersection planes formed by the four rectangular prisms. The LCOS modulator includes a first LCOS modulator (122c), a second LCOS modulator (122d), and a third LCOS modulator (122e). The first LCOS modulator (122c), the second LCOS modulator (122d), and the third LCOS modulator (122e) are respectively disposed on light emitting sides of three different sides. At least two of the four intersection planes are configured to split light emitted from the light source (111) in the light-combining prism (122a). At least two of the four intersection planes are configured to combine light emitted from the light source (111) in the light-combining prism (122a). The projection display apparatus can resolve a problem that the modulation module (12) has a large quantity of component parts and a complex structure.