One-point-of-view high-precision and versatile optical measurement of different sides of objects

Quality checking and part measurement are common needs in confectioning and manufacturing processes especially of electronic components. The complete part inspection of SMD- element, of connectors, of toy buildings blocks are such examples. For all these examples the demand arises to check parameters of different object sides by optical means with extremely high precision. The referred solution performs such inspection tasks from one point of view for (up to) five different sides, whereby four sides must be inspected for coplanarity and for the fifth the imprint quality has to be controlled. The optical set up uses special positioned mirrors combined with a sophisticated lighting system producing back light (coplanarity) as well as direct light (imprint inspection). The measurement procedure contains, of course, a calibration by help of a normal. The high precise measurement, better 10 micrometer, in the acquired image with a relatively low local resolution is reached by a spline based subpixel approach. Introducing cylindrical lenses or parabolic mirrors in the optical way allows to improve the potential accuracy for areas of interest, inside the view available for inspection.© (1999) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.