Focusing Properties of Single-Focus Photon Sieve

In this letter, we present a single-focus photon sieve (SFPS), which can produce single focus with suppressed sidelobes, featuring a higher signal-to-noise ratio and improved image contrast. This is achieved through combining single-focus zone plates (SZPs) and photon sieves (PSs). Simulations and experiments were conducted to verify the single focusing property of SFPSs. The results illustrated the advantages of SFPSs over conventional PSs, as well as improved resolution compared with SZPs in terms of the same specific minimum feature size. SFPSs are extremely promising to replace PSs and Fresnel zone plates in the fields such as X-ray focusing, imaging, and nanometer lithography.