A self-focusing method applicable to digital lensless holographic microscopy is presented. The method searches for the global minimum of the area enclosing a given amount of energy in a region surrounding the object of interest. The proposed modified enclosed energy method has been tested on self-focusing experimental holograms of a paramecium specimen and a section of the head of a drosophila melanogaster fly. The presented self-focusing technique also has been contrasted with some of the already reported methods to seek the best focus image.
© 2014 Optical Society of America
Original Manuscript: February 21, 2014
Revised Manuscript: March 24, 2014
Manuscript Accepted: March 25, 2014
Published: April 18, 2014
Vol. 9, Iss. 7 Virtual Journal for Biomedical Optics
Carlos A. Trujillo and Jorge Garcia-Sucerquia, "Automatic method for focusing biological specimens in digital lensless holographic microscopy," Opt. Lett. 39, 2569-2572 (2014)