公开(公告)号：US5497227A

公开(公告)日：1996-03-05

申请号：US122265

申请日：1993-08-16

申请人： Itsuo Takeuchi ,  Hidekazu Hoshino ,  Mutumi Sasaki

发明人： Itsuo Takeuchi ,  Hidekazu Hoshino ,  Mutumi Sasaki

IPC分类号： B42D15/10 ,  G02B27/28 ,  G06K7/10 ,  G06K19/06 ,  G06K19/10 ,  G06K19/16 ,  G06T1/00 ,  G07F7/08 ,  G06K9/74 ,  G03H1/00

CPC分类号： G06K7/10831 ,  G03H1/0252 ,  G03H1/0272 ,  G06K19/06009 ,  G06K19/16 ,  G03H1/0011 ,  G03H1/0244 ,  G03H2222/31 ,  G03H2240/55 ,  G03H2250/36 ,  G03H2250/41 ,  G06K2019/0629

摘要： Provided is an identification system which is highly effective in identifying the authenticity of an object and extremely difficult to analyze for the purpose of forgery. The object to be identified is affixed with an identification element comprising a reflective layer including a hologram, a diffraction grating or the like, which directs incident light of a prescribed wave length into a plurality of point symmetric directions, and a polarization plane rotating layer which rotates the polarization plane of the light as it passes through the polarization rotating layer. A linearly polarized light is impinged upon the identification element, and is received by a multisegment photodiode arranged in an annular fashion. Those photodiode segments located on one side of a diametric line is covered by a first filter adapted to transmit substantially only the light emitted from the identification element whose plane of polarization is rotated by the polarization plane rotating layer while remaining segments are covered by a second filter adapted to transmit substantially only the light emitted from the identification element whose plane of polarization is not rotated by the polarization plane rotating layer. Thus, by detecting the ratios of the intensities of light received by each pair of diametrically opposing photodiode segments, the authenticity of the identification element or the authenticity of the object can be reliably detected.

摘要翻译： 提供了一种识别系统，其在识别对象的真实性方面非常有效，并且为了伪造的目的极难分析。 要识别的对象被附加有识别元件，该识别元件包括将包括预定波长的入射光引导成多个点对称方向的全息图，衍射光栅等的反射层，以及偏振面旋转层， 当光通过偏振旋转层时，使光的偏振平面旋转。 线性偏振光照射在识别元件上，并被以环形方式布置的多分辨光电二极管接收。 位于直径线一侧的那些光电二极管部分被第一滤光片覆盖，该第一滤光器适于基本上仅传输由偏振平面旋转层旋转的偏振面旋转的识别元件发射的光，而剩余的部分被第二滤光片覆盖 适于仅透射从偏振面旋转层不偏振的偏振面的识别元件发出的光。 因此，通过检测由每对直径相对的光电二极管段所接收的光的强度的比率，可以可靠地检测识别元件的真实性或物体的真实性。