Projection apparatus with coherent light source
View Patent ↗The present invention discloses a projection apparatus comprising: a light source for emitting illumination light; a mirror device comprising a plurality of mirrors for generating an image by reflecting the illumination light toward a projecting direction by means of a deflecting operation; and a projection optical system which is placed in the optical axis of reflection light in the projecting direction of the illumination light incident to the mirror device and which projects the reflection light, wherein the optical axis of the illumination light incident to the mirror device and the optical axis of the reflection light in the projecting direction forms an angle that is larger than the expansion angle α of the flux of the illumination light that satisfies NA=n*sin α, where NA is the numerical aperture of the flux of the illumination light, and n is the reflectance.
1. A projection apparatus comprising:
a light source for emitting an illumination light with an expansion angle to a mirror device having a plurality of micromirrors for modulating and reflecting the illumination light to an image projection optical system for displaying an image, wherein each of the micromirrors is controlled to oscillate between a minimum deflection angle and a maximum deflection angle and an angular difference between the minimum deflection angle and the maximum deflection angle is greater than the expansion angle α of the light flux of the illumination light according to a function relationship:
NA=n *sin α,
where NA is the numerical aperture of the flux of the illumination light, and n is the reflectance.
2. The projection apparatus according to claim 1 , wherein:
the light source is a laser light source.
3. The projection apparatus according to claim 1 , wherein:
the mirror performs a deflecting operation on the basis of a deflection axis going through an approximate center of the present mirror.
4. The projection apparatus according to claim 1 , wherein:
the minimum deflection angle and the maximum deflection angle of the mirror are symmetrical between the clockwise (CW) direction and counterclockwise (CCW) direction relative to an initial state of the mirror.
5. The projection apparatus according to claim 1 , wherein:
the minimum deflection angle and the maximum deflection angle of the mirror are asymmetrical between the clockwise (CW) direction and counterclockwise (CCW) direction relative to the initial state of the mirror.
6. A color projection apparatus comprising:
a light source projects an illumination light as a light flux having an expansion angle;
a color separator for separating the light from the light source into a plurality of illumination lights with respective colors;
a plurality of mirror devices each comprising a plurality of deflecting mirrors controllable for deflecting and reflecting the illumination light toward an image projection direction to project and display an image;
a color synthesizer for synthesizing lights reflected by the mirrors toward the image projection direction as a synthesized light; and
a projection optical system disposed approximately in the optical axis of the synthesized light, wherein
an angle between a direction of the illumination light incident to the mirror device and the image projection direction is larger than the expansion angle α of the light flux of the illumination light according to a function relationship:
NA=n *sin α,
where NA is the numerical aperture of the flux of the illumination light, and n is the reflectance.