An Active Intraoral Shape Measurement Scheme Using a Compact Compound-Eye Camera with Integrated Pattern Projectors

We propose an active intraoral shape measurement scheme to realize a compact intraoral diagnostic system for measuring the three-dimensional shapes of gums and teeth. To measure intraoral surfaces with little texture, compact pattern projectors based on diffractive optical elements are integrated in lens gaps of a compact compound-eye camera called a thin observation module by bound optics (TOMBO). The three-dimensional shape is reproduced on the basis of triangulation using the amount of pattern distortion. A scaled-up prototype system is constructed to verify the measurement; scheme using the TOMBO camera and a spatial light modulator. The prototype system demonstrates an rms distance accuracy of 0.46 mm. A temporal change of the shape is quantitatively evaluated with a reference surface based on teeth positions. (C) 2009 The Japan Society of Applied Physics