Accurion EP4, our latest imaging ellipsometer, combines ellipsometry and microscopy for precise characterization of thickness and refractive index on microstructures as small as 1 µm. Unlike conventional ellipsometers, all structures inside the field of view are measured simultaneously. The EP4 provides ellipsometric-contrast live-view, allowing detection of sub-nm features and identification of regions of interest for obtaining values and 3D maps of thickness (0.1 nm - 10 µm) and refractive index. Additional accessories are available to expand measurements under controlled conditions or temperature variations.