Light source device and projector
A light source section is provided with a plurality of light sources. A pitch of the light sources in a first direction and a pitch in a second direction are regulated in accordance with a specific cross-sectional shape of a light beam.
1. A light source device comprising:
a light source section having a plurality of light sources,
wherein each of the light sources emits a radial light beam,
a divergence of the radial light beam in a first direction is greater than a divergence of the radial light beam in a second direction perpendicular to the first direction,
the light sources are arranged so as to form a plurality of light source columns parallel to each other and extending in the first direction,
when denoting a pitch of the light sources in the first direction by P 1 , and a pitch of the light source columns by P 2 , P 1 is larger than P 2 , and
when denoting a divergence angle of the radial light beam in the first direction by θ ⊥ , and a divergence angle of the radial light beam in the second direction by θ ∥ , the following formula:
tan θ ∥ /tan θ ⊥ ≦P 2/ P 1<1.0
is fulfilled.
2. The light source device according to claim 1 , wherein
the radial light beam has an intensity distribution according to a Gaussian distribution, and
the divergence angles are each an angle at which the intensity of the radial light beam is equal to a value obtained by multiplying 1/e 2 by an intensity on an optical axis of the radial light beam.
3. The light source device according to claim 1 , further comprising:
a collimating lens array including a plurality of lens elements disposed so as to correspond to the plurality of light sources.
4. The light source device according to claim 3 , wherein
in the collimating lens array, some of the lens elements constituting a contour portion of the collimating lens array are arranged in accordance with a contour of an irradiation target in a posterior stage, to which the light emitted from the light source section is input.
5. The light source device according to claim 1 , wherein
each of the light sources is a solid-state light source.
6. The light source device according to claim 5 , wherein
the solid-state light source is a laser source.
7. The light source device according to claim 1 , further comprising:
an afocal optical system adapted to regulate a cross-section of a light beam emitted from the light source section;
a lens array integrator disposed in a posterior stage of the afocal optical system, and adapted to divide light input to the lens array integrator, and emit the light so as to overlap at a predetermined position; and
an object disposed at the predetermined position.
8. The light source device according to claim 7 , wherein
the object is one of a diffusion plate adapted to diffuse the light and a phosphor layer adapted to generate a fluorescence.
9. The light source device according to claim 7 , further comprising:
a rotary plate adapted to rotatably hold the object.
10. A projector comprising:
the light source device according to claim 1 ;
a light modulation device adapted to modulate the light from the light source device in accordance with image information; and
a projection optical system adapted to project the modulated light from the light modulation device as a projection image.
11. A projector comprising:
the light source device according to claim 2 ;
a light modulation device adapted to modulate the light from the light source device in accordance with image information; and
a projection optical system adapted to project the modulated light from the light modulation device as a projection image.
12. A projector comprising:
the light source device according to claim 3 ;
a light modulation device adapted to modulate the light from the light source device in accordance with image information; and
a projection optical system adapted to project the modulated light from the light modulation device as a projection image.
13. A projector comprising:
the light source device according to claim 4 ;
a light modulation device adapted to modulate the light from the light source device in accordance with image information; and
a projection optical system adapted to project the modulated light from the light modulation device as a projection image.
14. A projector comprising:
the light source device according to claim 5 ;
a light modulation device adapted to modulate the light from the light source device in accordance with image information; and
a projection optical system adapted to project the modulated light from the light modulation device as a projection image.
15. A projector comprising:
the light source device according to claim 6 ;
a light modulation device adapted to modulate the light from the light source device in accordance with image information; and
a projection optical system adapted to project the modulated light from the light modulation device as a projection image.
16. A projector comprising:
the light source device according to claim 7 ;
a light modulation device adapted to modulate the light from the light source device in accordance with image information; and
a projection optical system adapted to project the modulated light from the light modulation device as a projection image.
17. A light source device comprising:
a light source section having a plurality of light sources; and
a collimating lens array including a plurality of lens elements disposed so as to correspond to the plurality of light sources,
wherein each of the light sources emits a radial light beam,
a divergence of the radial light beam in a first direction is greater than a divergence of the radial light beam in a second direction perpendicular to the first direction,
the light sources are arranged so as to form a plurality of light source columns parallel to each other and extending in the first direction,
when denoting a pitch of the light sources in the first direction by P 1 , and a pitch of the light source columns by P 2 , P 1 is larger than P 2 ,
a first lens element of the plurality of lens elements corresponds to a first light source of the plurality of light sources, and
when denoting a distance between the first light source and the first lens element by D, an effective lens width of the first lens element in the first direction by H 1 , an effective lens width of the first lens element in the second direction by H 2 , a divergence angle of the radial light beam in the first direction by θ ⊥ , and a divergence angle of the radial light beam in the second direction by θ ∥ , the following relation:
tan θ ⊥ ≦H 1/(2× D ) and
tan θ ∥ ≦H 2/(2× D )
is fulfilled.
18. The light source device according to claim 17 , wherein
the radial light beam has an intensity distribution according to a Gaussian distribution, and
the divergence angles are each an angle at which the intensity of the radial light beam is equal to a value obtained by multiplying 1/e 2 by an intensity on an optical axis of the radial light beam.
19. The light source device according to claim 17 , wherein
in the collimating lens array, some of the lens elements constituting a contour portion of the collimating lens array are arranged in accordance with a contour of an irradiation target in a posterior stage, to which the light emitted from the light source section is input.
20. The light source device according to claim 17 , wherein
each of the light sources is a solid-state light source.
21. The light source device according to claim 20 , wherein
the solid-state light source is a laser source.
22. The light source device according to claim 17 , further comprising:
an afocal optical system adapted to regulate a cross-section of a light beam emitted from the light source section;
a lens array integrator disposed in a posterior stage of the afocal optical system, and adapted to divide light input to the lens array integrator, and emit the light so as to overlap at a predetermined position; and
an object disposed at the predetermined position.
23. The light source device according to claim 22 , wherein
the object is one of a diffusion plate adapted to diffuse the light and a phosphor layer adapted to generate a fluorescence.
24. The light source device according to claim 22 , further comprising:
a rotary plate adapted to rotatably hold the object.