Axial-resolution in depth from focus digital holography

We use digital holography to quantify surface topography of rough objects in full-field. We calculate the variance of the intensity image as a focus metric over a set of reconstruction distances for each pixel, which results in a focus metric curve. The distance where the variance peaks is an estimate for the depth. First we analyze the lateral...

Holographic wavefield imaging for surface reconstruction and 3d tomography

Optical imaging is the imaging of objects with visible light. It is a tool often used for diagnostic purposes, such as in biomedical and material sciences. Digital holography is an optical imaging technique that captures and images the amplitude as well as the phase (the complex amplitude) of the lightwave. An advantage is that the complex...

Lensless coherent imaging by sampling of the optical field with digital micromirror device

We have experimentally demonstrated a lensless coherent microscope based on direct registration of the complex optical field by sampling the pupil with a sequence of two-point interferometers formed by a digital micromirror device. Complete registration of the complex amplitude in the pupil of the imaging system, without any reference beam,...