| CPC B42D 25/47 (2014.10) | 11 Claims |

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1. An anti-counterfeiting apparatus comprising:
a first layer formed of a flexible material and including a high-corrugation region and a low-corrugation region;
a second layer adhered to the first layer, formed in a pattern on an upper portion of the high-corrugation region and formed of a material having a Young's modulus greater than that of the first layer;
a third layer adhered to the first layer to cover the low-corrugation region and the second layer, and formed of a material having a Young's modulus greater than that of the first layer and a Young's modulus smaller than that of the second layer; and
an adhesive layer configured to adhere the first layer, the second layer and the third layer,
wherein each of the first layer, the second layer, the third layer and the adhesive layer satisfies Equation 2:
![]() wherein Xi is a distance between an outer surface of the first layer and a center plane of each corresponding layer,
dn is a distance between the outer surface of the first layer and a neutral plane,
εYi is a yield strain of each corresponding layer, and
r is a radius of curvature of the anti-counterfeiting apparatus, and
wherein the center plane bisects the thickness of each corresponding layer and the neutral plane has an average stiffness of all layers of the anti-counterfeiting apparatus.
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