Structured illumination for resolution enhancement and autofocusing in digital holographic microscopy.

In this Letter we show how resolution enhancement and autofocusing in digital holographic microscopy is obtained by using structured illumination generated by a spatial light modulator, which enables it to project fringes of different orientations and phase shift without mechanical movement. The image plane is numerically determined by searching for the minimal deviation between the reconstructed images carried by different diffraction orders of the structured illuminations.