PURPOSE: To provide the additionally higher security characteristic and to visually check an information pattern while the constitution is simple by providing a wavelength selection layer which shuts off visible light and allows the transmission of IR light in the upper layer of a specific information recording region.
CONSTITUTION: The wavelength selection layer which shuts off the visible light and allows the transmission of the IR light is provided in the upper layer of the hologram recording surface recorded with the specific information. The specific information recording region of a hologram sheet 10 is irradiated with the incident light 51 emitted from a semiconductor laser 50 at the time of reading the hologram sheet 10. This reproducing light 54 images and reproducing the specific information pattern on an imaging plate 57 disposed in a prescribed position. The reproducing light 54 of the specific information pattern consisting of IR light is visualized by the wavelength conversion layer 55 of the imaging plate 57 and is converted to a specific information pattern image 58 consisting of the visible light. This specific information pattern image 58 is inverted by a mirror 59 and is thus made visible. The mirror 59 is disposed to make the image easily visible from above and may not exist.
MATSUDAIRA OSAHISA
KOBAYASHI AKIHIKO
