Flexible X-ray Talbot-Lau grating interferometer

In X-ray Talbot-Lau grating interferometer, the system layout is determined by Talbot effect and Lau effect. Generally, the imaging systems should be arranged according to the designed parameters. In this paper, we report a flexible X-ray Talbot-Lau grating interferometer, which is similar to non-interferometric phase contrast imaging system. The visibility remains mostly high, when only Lau condition is satisfied. This is exciting, especially for shorter system than the designed one. We analyze the reason of the relaxed Talbot condition, which is validated by simulation. Finally, we report experimental results of some samples, imaged by the flexible interferometer with three different system lengths.