In this communication we propose a design combining the advantages of the space invariance of telecentric triangulation with high relative lateral resolution and large measuring volume at the same time. Because the scan motion of the laser beam is decoupled from physical transport of the sensor head, this enables the fast scan in large volume. However we need a large aperture optics as large as the scan areas. We used a liquid mirror as aperture for this scanner. The surface of a spinning reflecting liquid takes the shape of a paraboloid that can be used as a reflecting mirror. This very old and nearly forgotten concept as recently been revived, with success. Low costs, large sizes, high optical qualities are the main advantages of liquid mirrors. The main limitation of liquid mirrors come from the fact that the optical axis must be aligned vertically and cannot be tilted. The prototype involves a stand-off distance of 1.5 meters, a scan length up to 1 meter (telecentric), a depth of view of 1 meter and a relative depth resolution of 1 mm (can be less). The design is based on the auto-synchronized scanner and is well corrected for field scanning distortion (f-0).
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