Shape from stereo images for small objects

A novel method of shape estimation from stereo images is presented, which is based on geometrical relations targeting small objects. Each of left and right images consists of a number of images obtained with different focusing distances, taking a limited depth of focus into account. In the absence of enough textures, the object is made to have artificial textures, for example, by putting carbon powders on its surface. Shapes were experimentally obtained for an object of size 8.2 × 4.5 × 3.5 mm³ to show the procedure and to examine the method. The method may be useful to observe shapes for small objects.