Laboratório de Mecânica Teórica e Aplicada, Departamento de Engenharia Mecânica, Universidade Federal Fluminense, Niterói, RJ, Brazil.
Opt Lett. 2013 Mar 15;38(6):1004-6. doi: 10.1364/OL.38.001004.
In this Letter, low-frequency photorefractive holographic moiré fringe patterns are proposed as secure numerical code generators that could be useful for storage or data transmission. These dynamic moiré patterns are holographically obtained by the superposition of two or more sinusoidal gratings with slightly different pitches. The Bi(12)TiO(20) photorefractive crystal sample is used as holographic medium. An optical numerical base was defined with patterns representing the 0, 1 and -1 digits as bits. Then, the complete set of these optical bits is combined to form bytes, where a numerical sequence is represented. The results show that the proposed numerical code is simple, robust and extremely secure, then could be used efficiently as standard numerical identification in robotic vision or eventually in storage or transmission of secure numerical data.
在这封信中，低频光折变全息莫尔条纹图案被提议作为安全的数字码生成器，可用于存储或数据传输。这些动态莫尔条纹图案是通过将两个或更多具有略微不同节距的正弦光栅叠加而全息获得的。Bi(12)TiO(20)光折变晶体样品用作全息介质。定义了一个光学数字基，其中图案代表 0、1 和 -1 数字作为位。然后，将这些光学位的完整集合组合形成字节，其中表示数字序列。结果表明，所提出的数字码简单、鲁棒且极其安全，因此可有效地用作机器人视觉中的标准数字识别，或者最终用于安全数字数据的存储或传输。
