Identification medium and method for identification thereof
AssigneeNHK Spring Co., Ltd.
InventorTohru Ida
Life of this patent
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AssigneeNHK Spring Co., Ltd.
InventorTohru Ida
Estimating the term…
An identification medium, in which a pattern is clearly altered in observation through a right-handed circularly polarizing filter and observation through a left-handed circularly polarizing filter, is provided. The identification medium is formed by laminating a cholesteric liquid crystal layer, a λ/4 plate, and a linearly polarizing filter layer, in that order, from an observing side. The cholesteric liquid crystal layer is formed with a hologram and selectively reflects light. In an observation through a circularly polarizing filter that transmits the light reflected at the cholesteric liquid crystal layer, light reflected at a pattern printed layer is not perceived due to the function of a circularly polarizing layer. Images are clearly altered by switching a right-handed and a left-handed circularly polarizing filter.
An identification medium, which reflects circularly polarized light having a first circling direction and circularly polarized light having a second circling direction that is opposite to the first circling direction, the medium comprising:
Dependencies are inferred from the claim text.