Single-shot phase-shifting digital holography with amplitude-only Fermat-spiral sieves

Single-shot phase-shifting digital holography is considered as a promising imaging method, but traditional one-shot exposure has its own limitation in short wavelength regions. Here, an amplitude-only Fermat-spiral sieve is suggested to be used for holographic imaging from coherent x-rays to terahertz wave. In the single-shot phase-shifting digital holography, we have designed an amplitude-only Fermat-spiral sieves to produce the reference wave and split the object wave into several parts by an equal-intensity splitting grating, and then verify the validity of our proposed single-exposure method by measuring a 1951 U.S. air force resolution test target. The experimental result is in good agreement with the theoretical analysis. With advantages of operating in real time, reducing the effects of vibration, widely-used for phase measurement and no limitations at shorter wavelengths, this kind of one-shot exposure technique will have great potential in x-rays holography and biochemical microscopy for the next generation of synchrotron radiation and free electron laser.