Nitto-denko Corporation

Nhk Spring Co., Ltd.

Kazuhito Kouno

Seiji Umemoto

Itsuo Takeuchi

Tokio Sakauchi

Tohru Ida

Kazumasa Shibata

Provided is a multilayer reflector about which a complicated step is not required when the molecular alignment of a retardation film is partially relaxed to form a latent image of authentication information, and about which the latent image is not made visible by the generation of unevenness in the surface. A multilayer reflectorhas a retardation filmin which the phase difference &#x394;ndto an observation wavelength &#x3bb; is set to be m&#xd7;&#x3bb;/4&#x2212;&#x3bb;/16&#x2266;&#x394;nd&#x2266;m&#xd7;&#x3bb;/4+&#x3bb;/16 wherein m is a positive odd number, and a metallic reflectorlaminated on the rear face side of this retardation filmwherein an authentication regionwhere predetermined authentication information is beforehand formed in the retardation filmis formed to give a phase difference &#x394;ndset to be n&#xd7;&#x3bb;/4&#x2212;&#x3bb;/8 &#x2266;&#x394;nd&#x2266;n&#xd7;&#x3bb;/4+&#x3bb;/8 wherein n is 0 or a positive even number provided that n&#x3c;m, and further a light diffusing layeris formed on the front face side of the retardation film

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Ibaraki, Japan

Kazuhito Kouno