Collares-Pereira M, Rabl A, Winston R
Appl Opt. 1977 Oct 1;16(10):2677-83. doi: 10.1364/AO.16.002677.
By the addition of suitable reflectors the concentration of a lens can be increased to the thermodynamic limit, which is equivalent to an f-number of one half. Such lens-mirror combinations are useful whenever concentration rather than image formation is important, for example, in radiation detectors and solar energy collectors. The design of lens-mirror combinations with maximal concentration is described. To the approximation that the lens has sharp focal points at off-axis incidence, the solution for the reflector is readily found to be compound hyperbolic. With proper choice of the f-number of the lens the hyperbolic reflector reduces to a V-trough or cone, an arrangement which offers considerable advantages for fabrication. The 2-D case (line focus lens) suffers from aberrations due to focal length variation with nonplanar incidence. The optical performance of 2-D lens-mirror combinations at nonplanar incidence is analyzed and evaluated for its suitability in solar energy applications. A prototype Fresn l lens plus V-trough has been built, and test data are presented.
通过添加合适的反射镜，透镜的聚光能力可以提高到热力学极限，这相当于f数为二分之一。每当聚光而非成像很重要时，例如在辐射探测器和太阳能收集器中，这种透镜-反射镜组合就很有用。文中描述了具有最大聚光能力的透镜-反射镜组合的设计。在透镜在离轴入射时具有清晰焦点的近似情况下，很容易发现反射镜的解是复合双曲线形的。通过适当选择透镜的f数，双曲线形反射镜可以简化为V形槽或圆锥体，这种结构在制造方面具有相当大的优势。二维情况（线聚焦透镜）由于焦距随非平面入射而变化，会产生像差。分析并评估了二维透镜-反射镜组合在非平面入射时的光学性能，以确定其在太阳能应用中的适用性。已经制造了一个菲涅耳透镜加V形槽的原型，并给出了测试数据。
