A compound multilayer Laue lens with multiple tilting angles

The multilayer Laue lens (MLL) is a diffractive focusing optic with large aspect ratio, where dynamical diffraction effects dominate the focusing performance. Owing to the dynamical diffraction effects, the tilted MLL cannot effectively focus hard X-ray to below 10 nm; in contrast, the wedged MLL can theoretically focus hard X-ray to below 1 nm with very high efficiency, but it is more difficult to fabricate than tilted MLL. Here, a new structure of MLL and its design method are proposed, namely compound MLL with multiple tilting angles, which can focus the hard X-ray to below 10 nm with high efficiency and be easier to fabricate than wedged MLL.