Light source unit including a laser as a light source and a light emitting wheel with a diffusion layer opposite to the laser

摘要

A projector includes a light source unit, a light guiding device, a display device, a projection side optical system, and a projector control unit. The light source unit includes a light source which emits laser light in the wavelength band of blue, a light emitting wheel disposed on an optical axis of the light source, and a wheel motor for driving to rotate the light emitting wheel. The light emitting wheel is formed of a circular substrate having a diffusion layer on a predetermined surface thereof, the diffusion layer being made up of minute irregularities which are formed directly on a surface of the circular substrate.

主权项

1. A light source unit comprising:
a blue laser light source for emitting laser light in the wavelength band of blue; a circular-shaped substrate which is configured so as to be rotatably driven, in which a fluorescent material layer for emitting light by using the laser light emitted from the blue laser light source as excitation light is disposed in, a circumferential direction of the circular-shaped substrate in an annular shining area so as to be positioned on an optical axis of the blue laser light source; wherein the circular-shaped substrate has a reflecting layer which is formed all over a surface at a side of the circular-shaped substrate opposite the blue laser light source; wherein the fluorescent material layer is disposed on the reflecting layer and comprises at least a green area which emits light in the wavelength band of green by using the laser light emitted from the blue laser light source as excitation light; wherein an opening is formed in a part of the circular-shaped substrate, a light transmissive area is disposed at the opening, and the opening transmits the blue laser light emitted from the blue laser light source; wherein when the blue laser light emitted from the blue laser light source is incident on the fluorescent material layer as excitation light, the reflecting layer reflects toward the blue laser light source both the light which is emitted by the fluorescent material layer, and the laser light from the blue laser light source that is transmitted through the fluorescent material layer, so that the laser light from the blue light source that is transmitted through the fluorescent material layer is reflected to be incident again on the fluorescent material layer as excitation light; and wherein a dichroic mirror is disposed between the blue laser light source and the circular-shaped substrate so as to transmit the laser light emitted from the blue laser light source and reflect the light emitted from the fluorescent material layer.