Tomofumi Kitazawa

Radial and Tangential-Tilt Servo Using Four-Axis Actuator

A two-axis tilt servo using a four-axis object-lens actuator was developed. The four-axis actuator can tilt the object lens in the radial and tangential directions, and can move it to allow axial tracking or radial tracking. The tilt servo was applied on an optical disc system for next-generation digital versatile discs using a blue-violet laser, and the effect of disc-tilt compensation was determined experimentally. These experiments show that the tilt servo with the four-axis object lens actuator reduces tilt by 0.1 deg in the cases of a disc tangential tilt to 0.43 deg and a disc radial tilt to 0.47 deg.

Desktop 2d/3d image capturing system using a digital camera

As electronic documents are becoming more and more popular, variety of objects, including 2D and 3D objects such as articles, books and 3D-shapes, can be easily contained in a document. Conventional systems cannot capture these objects as a 3D form. We developed a new image capturing system with 3D information for deskwork. It is an assemblage of a normal digital camera and its docking station designed for easy operation. The docking station swings the attached camera tilting step by step. Within a few steps, it covers the whole object automatically. Then each frame is combined together into one complete image with full resolution. In order to get precise 3D structure, stripe patterns are projected by a modified flash light attached on the camera. The resolution rises by means of the swing to be slipped the patterns on the object. Using the obtained 3D data we can reconstruct a correct image from a splay surface image such as a book. Experimental Results of image mosaicking and 3D reconstruction shows that the system is practical.