Focus sensor with integrated high-range slope measurement

Focus sensors and deflectometric sensors find widespread application in optical testing, especially where a large measurement range is required as in plastics or free-form optics. This note describes the design of a combined sensor for the simultaneous measurement of the height and the local slope of a surface under test in one single measurement spot. The opto-mechanical set-up and the metrological characteristics are described in detail and the benefits of the integrated measurement are stated, e. g. for the correction of the slope-dependent signal of the focus distance signal or the enhanced characterization of optical surfaces. First measurement results on a spherical micro mirror array are shown.