Xu Xiaoyi, Chen Pengcheng, Ma Taxue, Ma Jianan, Zhou Chao, Su Yawen, Lv Mingxin, Fan Weiwen, Zhai Bohan, Sun Yuyang, Wang Tianxin, Hu Xiaopeng, Zhu Shi-Ning, Xiao Min, Zhang Yong
National Laboratory of Solid State Microstructures, College of Engineering and Applied Sciences, School of Physics, and Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing 210093, China.
Department of Physics, University of Arkansas, Fayetteville, Arkansas 72701, United States.
Nano Lett. 2024 Jan 31;24(4):1303-1308. doi: 10.1021/acs.nanolett.3c04286. Epub 2024 Jan 17.
A nonlinear holographic technique is capable of processing optical information in the newly generated optical frequencies, enabling fascinating functions in laser display, security storage, and image recognition. One popular nonlinear hologram is based on a periodically poled lithium niobate (LN) crystal. However, due to the limitations of traditional fabrication techniques, the pixel size of the LN hologram is typically several micrometers, resulting in a limited field-of-voew (FOV) of several degrees. Here, we experimentally demonstrate an ultra-high-resolution LN hologram by using the laser poling technique. The minimal pixel size reaches 200 nm, and the FOV is extended above 120° in our experiments. The image distortions at large view angles are effectively suppressed through the Fourier transform. The FOV is further improved by combining multiple diffraction orders of SH fields. The ultimate FOV under our configuration is decided by a Fresnel transmission. Our results pave the way for expanding the applications of nonlinear holography to wide-view imaging and display.
一种非线性全息技术能够在新产生的光频率中处理光学信息，从而在激光显示、安全存储和图像识别等方面实现引人入胜的功能。一种常见的非线性全息图基于周期性极化铌酸锂（LN）晶体。然而，由于传统制造技术的限制，LN全息图的像素尺寸通常为几微米，导致视场（FOV）仅为几度。在此，我们通过使用激光极化技术实验演示了一种超高分辨率的LN全息图。在我们的实验中，最小像素尺寸达到200纳米，视场扩展到120°以上。通过傅里叶变换有效抑制了大视角下的图像失真。通过组合SH场的多个衍射级进一步改善了视场。我们配置下的最终视场由菲涅耳透射决定。我们的结果为将非线性全息术的应用扩展到宽视角成像和显示铺平了道路。
