Solar light collecting device

PURPOSE: To make a solar light collecting device compact and facilitate its operation by a method wherein a complex parabolic plane mirror and a concave lens are combined to increase a light collecting ratio. CONSTITUTION: A complex parabolic plane mirror 9 is combined with a concave lens 8. The concave lens 8 is made such that an angle of light after incident forms with an optical axis of the lens is less than an allowable angle of the complex parabolic plane mirror 9. The concave lens 8 does not receive directly the solar light, but receives the solar light once collected through a Fresnel lens 2, so that a substantial allowable incident angle can be made large irrespective of the fact that an apparent allowable incident angle of the concave lens 8 is low. Thus, it is possible to increase the light collecting ratio without chasing the sun. With such an arrangement, it is possible to make a compact solar light collecting device and to perform an easy operation. COPYRIGHT: (C)1993,JPO&Japio