Fast Focus Mechanism Using a Pair of Convergent and Divergent Lenses Differentially for Three-dimensional Imaging
نویسنده
چکیده
Telecentric optics with a fast focus mechanism at constant magnification was devised to achieve perfect perspective and parallel projections for a real-time system of three-dimensional close-up imaging and range measurement based on focus by differentially using a pair of convergent and divergent lenses. This was successfully used to keep the parallel and perspective projection systems in focus with a focusing precision ( ) of 0.92 m for the former and a focusing precision ( ) of 0.25 mm for the latter. Furthermore, images that were entirely in focus were generated at a video rate of 30 Hz for a moving object within a desk top space.
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