Light emission device
A light emission device includes: a plurality of semiconductor light-emitting elements; an optical element configured to collimate light emitted from each of the plurality of semiconductor light-emitting elements and output a plurality of collimated beams; a converging portion having a surface of a hyperboloid or a paraboloid configured to converge the plurality of collimated beams; and a wavelength-converting portion including a transmissive region, and a reflective region that surrounds the transmissive region, the transmissive region including a light-incident surface at which the plurality of collimated beams that have been converged by the converging portion enter, wherein the transmissive region includes a phosphor adapted to be excited by the plurality of collimated beams that have been converged by the converging portion.
1. A light emission device comprising:
a plurality of semiconductor light-emitting elements;
an optical element configured to collimate light emitted from each of the plurality of semiconductor light-emitting elements and output a plurality of collimated beams;
a converging portion having a surface of a hyperboloid or a paraboloid configured to converge the plurality of collimated beams; and
a wavelength-converting portion comprising a transmissive region, and a reflective region that surrounds the transmissive region, the transmissive region including a light-incident surface at which the plurality of collimated beams that have been converged by the converging portion enter, wherein the transmissive region includes a phosphor adapted to be excited by the plurality of collimated beams that have been converged by the converging portion.
2. The light emission device of claim 1 , wherein the light-incident surface of the transmissive region intersects an optical axis of the converging portion, and is located off a focusing point of the converging portion.
3. The light emission device of claim 1 , wherein the plurality of collimated beams output from the optical element are parallel to one another.
4. The light emission device of claim 1 , wherein the plurality of semiconductor light-emitting elements are arranged in one or more rows and two or more columns or in two or more rows and one or more columns along a plane that is perpendicular to an optical axis of the converging portion.
5. The light emission device of claim 4 , wherein a surface shape of the converging portion is adapted to a shape of the light-incident surface of the transmissive region.
6. The light emission device of claim 1 , wherein the light-incident surface of the transmissive region has a rectangular shape.
7. The light emission device of claim 1 , wherein,
the converging portion is an aspherical lens; and
the aspherical lens has a conic constant k such that −15<k≤1.0.
8. The light emission device of claim 7 , wherein a focusing point of the aspherical lens is located between the aspherical lens and the light-incident surface of the transmissive region.
9. The light emission device of claim 8 , wherein the aspherical lens has a conic constant k such that −1.5≤k≤−1.0.
10. The light emission device of claim 1 , further comprising:
a housing in which the plurality of semiconductor light-emitting elements, the optical element, and the converging portion are housed,
wherein the housing comprises a lid configured to support the wavelength-converting portion, the lid having a throughhole through which the plurality of collimated beams that have been converged by the converging portion are allowed to pass.
11. The light emission device of claim 10 , wherein the wavelength-converting portion is supported by an edge of the throughhole of the lid.
12. The light emission device of claim 10 , wherein the housing comprises a sidewall portion and a support that protrudes inward from the sidewall portion and supports the converging portion.
13. The light emission device of claim 1 , wherein the light-emitting elements are laser diodes.
14. The light emission device of claim 13 , further comprising a package in which the plurality of laser diodes are hermetically sealed.
15. The light emission device of claim 1 , wherein the reflective region is made of a ceramic.
16. The light emission device of claim 15 , wherein the reflective region is made of aluminum oxide as a main material.