| 摘要 |
PROBLEM TO BE SOLVED: To suppress reduction in light-emission efficiency and life of a phosphor by enhancing an effect for cooling the phosphor.SOLUTION: A semiconductor light source 13 is arranged at an inside rear part of a housing 12, and a container 14 is installed at a front part of the housing 12, and a heat sink 15 is mounted on an upper surface of the housing 12. A phosphor solution 16 is encapsulated in the container 14 in a flowable manner. The phosphor solution 16 consists of a phosphor 17 excited by light from the semiconductor light source 13, and a solvent solution 18 giving the phosphor 17 fluidity. The phosphor 17 whose temperature is raised by heat generation is made to flow from a vertical part 19 of the container 14 to a horizontal part 20 together with the solvent solution 18. The phosphor 17 whose temperature is reduced by heat radiation is made to flow from the horizontal part 20 to the vertical part 19. The phosphor 17 is efficiently cooled down by convection of the solution 16. |
