| 摘要 |
Provided is an illumination optical system having fewer constituent components and a smaller size. This illumination optical system comprises: light sources (11, 41) for emitting light of a first wavelength; a phosphor unit (16); optical elements (13, 43); and a 1/4 wavelength plate (14) between the optical elements and the phosphor unit. The phosphor unit has a reflection region, and a phosphor region for giving off fluorescent light of a different wavelength than the first wavelength by being irradiated with the light of the first wavelength. The phosphor unit is able to move such that the light from the light sources sequentially irradiates the phosphor region and the reflection region. The optical elements separate the light of the first wavelength into a first linearly polarized light component and a second linearly polarized light component orthogonal to the first linearly polarized light component. The optical elements guide the first linearly polarized light component of the light emitted from the light sources to the phosphor unit, and light of the first wavelength reflected by the reflection region and fluorescent light given off by the phosphor region are released in the same direction. |
