A problem which is often encountered in machine vision applications is trying to view a long narrow or other odd shaped field with a rectangular video sensor. A variety of approaches have been demonstrated in the past to reconfigure a long image to better match the sensor format. The use of mirrors and beamsplitters is perhaps the most obvious of these approaches. However, the use of special prisms, such as rhombs and tyneoscopes offer some interesting solutions. A very versatile method we investigated is to use multiple lenses along the length of the part, which then feed one larger collection lens. The result of this lens system is to break a single long line into 4 or more segments which are presented as parallel lines on the video sensor. The merits, limitations, and potential applications of this lens based technique in comparison to the prism based methods described are discussed in this paper.
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