| 摘要 |
PURPOSE: To transmit as much illumination light as possible without being limited by the size of a light source, by disposing in position two concave mirrors each having a specific shape. CONSTITUTION: Light from a light source 10 is reflected by a first concave mirror 20 and a second concave mirror 30, and transmitted to an input aperture 42 of a non-imaging reflector 40. The light source 10 is disposed near the center of curvature of the first concave mirror 20, and forms a second image 32 at the input aperture 42 by the reflection of both the first concave mirror 20 and the second concave mirror 30. The light source 10 forms a third image 33 near the image 32 by the reflection of the second concave mirror 30 only. Because spherical mirrors with centers of curvature displaced or elliptic mirrors are used as the first and second concave mirrors, most of the light from the light source 10 is efficiently transmitted to the input opening 42. If the first concave mirror 20 adjoins the input aperture 42, the size of the light source 10 is not thereby limited. |
