Digital holography as a tool for testing high-aperture micro-optics

The large numerical aperture of the microlenses leads to high fringe densities in the holograms which cannot be resolved by CCD-detectors directly. In order to avoid this problem digital holography is combined with a multiple wavelength technique and a diffusing screen to capture the highly diverging wavefront. An averaging method to reduce the introduced speckle noise is applied and results of the characterization of refractive cylindrical microlenses are presented.