Full-field macroscopic measurement of specular, curved surfaces with SIM

SIM (Structured-Illumination Microscopy) allows the full-field acquisition of (rough and) specular surfaces at microscopic scale [1]. By using micro-objectives we achieved a measurement uncertainty of 10 nm. We will discuss, how this advantageous principle can be scaled up for a large field ("Structured-Illumination Macroscopy"). To accomplish this task, we are confronted with serious technological challenges and with interesting physical questions. First, a big field, high-NA objective with very good correction is necessary to obtain low measurement uncertainty and high angular dynamics. Second, the illumination needs a particularly designed setup to ensure that the entrance pupil is completely filled. We present the first implementation of a macroscopic setup by means of applying commercial photo-objectives (NA 0.95) and an OLED-display. Furthermore, we will discuss the physical and technological problems, such as the achievable local measurement uncertainty and the systematic error caused by the lens aberrations. [1] C. Kranitzky, C. Richter, C. Faber, M. C. Knauer, G. Häusler: "3D-microscopy with large depth of field", Proc. DGaO 110, A12 (2009).