An official website of the United States government
The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before
sharing sensitive information, make sure you’re on a federal
government site.
The site is secure.
The https:// ensures that you are connecting to the
official website and that any information you provide is encrypted
and transmitted securely.
Liu JP, Lee HY, Yau HF, Chen YZ, Chang CC, Sun CC.Liu JP, et al.Opt Lett. 2005 Feb 1;30(3):305-7. doi: 10.1364/ol.30.000305.Opt Lett. 2005.PMID: 15751893
Liu JP.Liu JP.J Opt Soc Am A Opt Image Sci Vis. 2011 Feb 1;28(2):229-37. doi: 10.1364/JOSAA.28.000229.J Opt Soc Am A Opt Image Sci Vis. 2011.PMID: 21293527