  We present a powerful and cost-effective method for active illumination using
a digital micromirror device (DMD) for quantitative phase imaging techniques.
Displaying binary illumination patterns on a DMD with appropriate spatial
filtering, plane waves with various illumination angles are generated and
impinged onto a sample. Complex optical fields of the sample obtained with
various incident angles are then measured via Mach-Zehnder interferometry, from
which a high-resolution two-dimensional synthetic aperture phase image and a
three-dimensional refractive index tomogram of the sample are reconstructed. We
demonstrate the fast and stable illumination control capability of the proposed
method by imaging colloidal spheres and biological cells, including a human red
blood cell and a HeLa cell.
