| 摘要 |
PURPOSE:To uniformly apply force to press a finger upon a whole finger in contact with a finger placing table, and to obtain a clear finger picture by arranging the finger placing table at the end part of the fitting surface of this table. CONSTITUTION:The surface T of a transparent prism 12 is exposed to the surface of a case body 11, and forms the same plane as the surface of the case body. Then the finger F can be easily placed on the prism. The prism 12 faces the finger placing table T, and an angle theta formed by its surfaces R and S is a right angle. It is arranged so that light from a light source 13 is total-reflected by the surface T so as to be made incident on a camera 14. Since the finger F can be placed on the finger placing surface T so that the force is applied uniformly upon the whole finger, illumination light is total- reflected at the non-contact part of a finger print or a joint part of the surface T, and is diffused-reflected at a contact part other than that part, and the clear finger picture can be obtained. |
