High speed 3-dimensional measurement by Shape from focus method using segmental focal images

This paper has presented the Shape from focus method using segmental focal images. The segmental focal image is defined by various focal lengths in one field of view. By using these images, the focal length at particular position changes in accordance with shifting the field of view. The experiment was conducted in a smooth, uninterrupted manner and allowed us a high-speed concatenated three-dimensional reconstruction. Furthermore, combining this method with frequency transfer analysis, a high-precision measurement was possible even if the shooting interval between source images were enlarged. 3-dimensional high speed measurement can be achieved by combining these two methods effectively. © 2010 The Institute of Electrical Engineers of Japan.