Differential interference contrast microscopy for cells using hard x-ray holography

We propose a differential interference contrast method for cells using hard x-ray Gabor holography and knife-edge filtering in the spatial frequency domain, without relying on beam shearing. A phase object is holographically recorded and reconstructed by computer. Interference between the wavefronts of zeroth order weighted by e^jπ/2 in the positive frequency region produces a dark image. Similarly, interference between the wavefronts of the zeroth order weighted by e^j3π/2 in the negative frequency region produces a bright image. By adding these two intensity distributions, good quality phase-contrast images of 8-μm-diameter polystyrene beads and human HeLa cells were obtained.