Development of the visual encryption device using higher-order birefringence

我们将提出一种由高阶双折射元件组成的新型视觉加密装置。当用白色光从一侧照射夹在一对偏振器之间的高阶双折射样品时，观察到具有白色颜色的样品。另一方面，当样品被单色光照射时，其透明光的亮度取决于波长。通过控制高阶双折射的量来制造加密设备，高阶双折射在偏振照明下仅在特定波长处给出高对比度。该装置可以通过特定阅读波长的照明来解码。

We will propose a new type of visual encryption device composed of higher-order birefringence elements. When a higher-order birefringence sample which is sandwiched between a pair of polarizer is illuminated with white light from one side, the sample with white color is observed. On the other hand, when the sample is illuminated by monochromatic light, its brightness of transparent light depends on a wavelength. The encryption device is fabricated by controlling the amount of higher order birefringence which gives a high contrast at only certain wavelength under polarized illumination. The device can be decoded by the illumination of specific reading wavelength.