Novel metal-dielectric metameric optical filters for optical security devices

作者：Guo Rong; Chen Nan; Chen Lu jian; Wang Xiao zhong; Cai Zhi ping; Li Yan kai; Bu Yi kun^*

来源：Optoelectronics Letters, 2014, 10(6): 411-414.

DOI：10.1007/s11801-014-4150-3

• Color difference
• Color saturation
• Dielectric multilayers
• Incident angles
• Manufacturability
• Matching effects
• Metal-dielectric multilayers
• Optical security device

Optical security devices play an essential role in the fight against counterfeiting. In this paper, we study and design a pair of metal-dielectric optical filters based on metameric effect, which offer a hidden image effect by the color shift at a specific angle of observation. Compared with all-dielectric multilayer system, the metal-dielectric multilayer structure has larger color shift with varying incident angle, higher color saturation and fewer layers. Finally, the stacks with 5 layers and 7 layers are achieved, and the color difference index is only 0.71, which shows good metameric matching effect. Simultaneously, the sensitivity of filters to deposition errors is analyzed when the thickness deviation is ±2%, and the results show that the two filters have good manufacturability.

• 出版日期2014
• 单位厦门大学