| 摘要 |
PURPOSE:To obtain clear image eliminating blur of the taken image by laying an object to be checked on the reflection surface of prism so that a ridge line formed by a surface of incidence and a surface of leading-out may extend in a longitudinal direction. CONSTITUTION:A finger 2 to take an image of finger-print of the object to be checked is laid on the surface of reflection surface 12 so that a ridge line formed by a surface of incidence 11 and a surface of leading-out 13 of triangle pillar type prism 1 may extend in the longitudinal direction. Thus, gradation of the taken image caused by triangle shape of prism is eliminated and a clear image of finger-print, etc. can be obtained. |
