A fast discrete curvelet transform based focus-stacking algorithm for extending the depth of focus of a transmission x-ray microscope (TXM) is presented. By analyzing an image stack of a sample taken in a Z-scan, a fully in-focus image can be generated by the proposed scheme. With the extended depth of focus, it is possible to obtain 3D structural information over a large volume at nanometer resolution. The focus-stacking method has been demonstrated using a dataset taken with a laboratory x-ray source based TXM system. The possibility and limitations of generalizing this method to a synchrotron based TXM are also discussed. We expect the proposed method to be of important impact in 3D x-ray microscopy.
© 2012 Optical Society of America
Original Manuscript: June 20, 2012
Manuscript Accepted: July 30, 2012
Published: August 30, 2012
Vol. 7, Iss. 11 Virtual Journal for Biomedical Optics
Yijin Liu, Junyue Wang, Youli Hong, Zhili Wang, Kai Zhang, Phillip A. Williams, Peiping Zhu, Joy C. Andrews, Piero Pianetta, and Ziyu Wu, "Extended depth of focus for transmission x-ray microscope," Opt. Lett. 37, 3708-3710 (2012)