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Diffractive optical element based sensor for surface quality inspection of concave punches.

V Hyvärinen·R Silvennoinen·K Peiponen·T Niskanen
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Abstract

Optical surface quality of concave shaped punches was investigated with a diffractive optical element based sensor. Image information of the present sensor was studied for the purpose of surface roughness and reflectance inspection. The robust sensor is proposed for off-line optical inspection of concave punches.

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V Hyvärinen, R Silvennoinen, K Peiponen, T Niskanen. 2000. Diffractive optical element based sensor for surface quality inspection of concave punches.. https://doi.org/10.1016/s0939-6411(99)00071-5

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