期刊
APPLIED OPTICS
卷 59, 期 7, 页码 2157-2164出版社
OPTICAL SOC AMER
DOI: 10.1364/AO.384502
关键词
-
类别
资金
- H2020 Marie Sklodowska-Curie Actions [642661]
Dark-field imaging is a well-known optical method for obtaining edge-enhanced images of objects containing steep gradients in either amplitude or phase. Edge enhancement is commonly achieved by using a small physical obstruction in the center of the Fourier plane of a 4f imaging setup. By blocking the low spatial frequencies in the center of the Fourier plane, only the higher spatial frequencies from the object reach the image plane. In this work, simultaneous optical image processing (i.e., dark-field imaging) and sum-frequency generation are performed by placing a periodically poled lithium niobate crystal in the Fourier plane of a 4f setup and using a 1575 nm upconversion pump beam with a dark core. We demonstrate upconversion dark-field (UDF) imaging in which edge-enhanced images are obtained at the upconverted wavelength (similar to 630 nm) as a result of infrared object illumination (similar to 1 mu m). Furthermore, we experimentally confirm that UDF imaging can be extended from collinear to noncollinear interactions between the signal and pump. The presented system allows for adjustment of the spatial cutoff frequency while maximizing the power conversion efficiency. Simultaneous collinear and noncollinear upconversion imaging of phase objects is demonstrated using broadband 1 mu m illumination with a spectral bandwidth of 6 nm-resulting in a UDF imaging system with an enhanced field of view at video frame rates. (C) 2020 Optical Society of America
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据