Binary pattern codification strategies in an active stereoscopic system based on flexible image guides

Abstract

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A Compact Active Stereovision System with Dynamic Reconfiguration for Endoscopy or Colonoscopy Applications

“…In the scope of the time multiplexing methods, phase-shift and gray code methods are two possibilities. Our study in [13] showed that the best reconstruction results were obtained with phase shift algorithms, however these algorithms need phase unwrapping and high number of patterns was needed to optimize the axial resolution. Gray code is well suited for lower resolution results, but with fewer projected patterns.…”

“…In order to design a compact system, flexible image guides have been integrated in a compact optical probe. This probe is an improved model of the one presented in [13] and its size is fitted for colonoscopy. The view angle switch is achieved with two miniature digital electromagnetic actuators on witch mobile mirrors are mounted.…”

Dynamic reconfiguration of a compact active stereovision system with digital electromagnetic actuators

“…It is connected to a miniaturized optical probe composed of a diaphragm and objective lenses as presented in [12]. The pattern coming from the image guide 1 enters into the optical probe and is projected onto the object surface.…”

“…By shifting the image guide through the focusing stages, an optical conjugation between the object to be measured and the ends of the image guides can be obtained. More details regarding this procedure is provided in [12]. The active part of the measuring system consists of three parts as shown as in Fig.5(b).…”

“…Combining these two results can be an additional way to enrich the surface information obtained from the measurement. In order to achieve miniature system, the flexible image guides combined with compact optical probes have been integrated to assure the miniaturization [12]. To our knowledge, no such system was previously reported in the literature.…”