Influence of the bridges on prism-array lens focusing for high energy X-rays

A kind of prism-array refractive lens (PRL) for X-ray focusing composed of different prisms with the same width is designed and fabricated. In order to stabilize the whole structure and reduce the fabrication difficulty, bridges are introduced between the opposite two lines of tooth-like segments. The influence of the bridges on the focusing is investigated in theory, which will broaden the width of the focus. Furthermore, two PRLs with and without bridges for 50 keV X-rays are fabricated on the same substrate by X-ray lithography and are tested at BL13W1 beamline in Shanghai Synchrotron Radiation Facilities (SSRF). The bridges are designed a width of 5μm and the PRL sample with bridges has the better morphology than the one without bridges after fabrication. The on-line focusing test results show that the focal line width of the samples with and without bridges are 4.20μm and 6.34μm respectively, which implies that the bridges are necessary for the PRL with this fabrication method.