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We present two versions of a chromatic confocal matrix sensor for the snapshot acquisition of three-dimensional objects. The first version contains separate illumination and detection pinhole arrays, while the second version uses a single pinhole array in double pass. The discrete lateral measurement points defined by the illumination and detection pinhole arrays are evaluated in parallel with a hyperspectral detection module. As this approach enables the spectrometric evaluation of all lateral channels, multilayer objects can be analyzed. To increase the lateral resolution the pinhole arrays are moved by micromechanical actuators. The paper includes a quantitative evaluation of the chromatic confocal module and proof-of-principle experiments with the full sensor system.

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We present a compact hyperspectral imaging system consisting of a combined refractive-diffractive optical element for extended longitudinal chromatic aberration, which provides spectrally resolved information of an object. This fully integrated hybrid device features a diffractive optical element (DOE) acting as a positive lens, a tunable concave liquid-filled membrane lens, and integrated magnetic actuation for hydraulically tuning the focal length of the membrane lens. The lens system is demonstrated to generate a hyperspectral data cube in the visible wavelength range by imaging the light from a pinhole array in a confocal approach onto a CCD camera.

A compact linear micromechanical stepping drive for positioning a 7 × 5.5 mm2 optical pinhole array is presented. The system features a step size of 13.2 µm and a full displacement range of 200 µm. The electrostatic inch-worm stepping mechanism shows a compact design capable of positioning a payload 50% of its own weight. The stepping drive movement, step sizes and position accuracy are characterized. The actuated pinhole array is integrated in a confocal chromatic hyperspectral imaging system, where coverage of the object plane, and therefore the useful picture data, can be multiplied by 14 in contrast to a non-actuated array.