Digital Holographic Microscopes (DHM) enables recording the whole information necessary to provide real time nanometric vertical displacement measurements with a single image acquisition. The use of fast acquisition camera or stroboscopic acquisition mode makes these new systems ideal tools for investigating the topography and dynamical behavior of MEMS and MOEMS. This is illustrated by the investigation of resonant frequencies of a dual axis micromirror. This enables the definition of the linear, non-linear, and modal resonance zones of its dynamical response.