Speaker: Amir Shemer
Affiliation: Bar Ilan University
(Seminar in conjunction with Prof. Ariel Schwarz)
Abstract: In gamma rays and x-rays imaging or particle streams, the usage of collimation and pinhole optics is necessary where no lens materials are available. For this reason pinhole optics is commonly used for x-ray astronomy and tomography applications. However, low sensitivity, dim and noisy image and long exposure time for photon acquisition are the main disadvantages of pinhole use. In order to preserve the advantages of pinhole optics together with solving the problems of sensitivity and low signal to noise ratio (SNR), many methods have been proposed over the years. Such methods include the use of high sensitivity detectors and camera films. Another method is based on the concept of using coded aperture imaging (CAI).
A new configuration of multi variable coded aperture (VCA) for gamma and x-ray imaging systems will be described in this talk. This configuration is able to provide super resolved planar images with improved sensitivity and signal to noise ratio as compared to single pinhole system. The configuration can be used to achieve depth information and to create three dimensional images. The imaging system is based on time multiplexing method using a variable multi pinhole array. The unique variable array design enable to overcome the spatial frequencies cutoff exists in standard multi pinhole array. The overall pinholes positions are designed to avoid spatial frequencies loss. The usage of multi pinhole array enables to achieve depth information and to obtain 3-D imaging. The operation principle will be described and illustrated with simulations of the imaging system; details will be presented with supporting material and significant results from several experiments that indicate the overall imaging performance.
Biography: Amir Shemer holds B.Sc. (1996) and M.Sc (2001) degrees in electrical engineering from Tel Aviv University (TAU), and Ph.D. degree (2011) in electrical engineering from Bar Ilan University (BIU). Between 2011 till now he managed the Electro optical Lab in Bar Ilan University. He is currently conducting research in the Faculty of Engineering, Bar-Ilan University. His major research interests include optical super resolution, biomedical optics, Nano-photonics and Electro-optical devices, Pinhole optics, Diffractive optical elements, and Beam shaping. He worked in several companies in the founding team and as advisor such as: Civcom Ltd (Optical switching devices), Xceed Ltd. (Enhanced DOF), ContinUse Biometrics Ltd. (optical biometric devices), and LensFree Ltd. (nuclear medicine and CT systems).
Date(s) - May 18, 2017
2:00 pm - 3:30 pm
E-IV Tesla Room #53-125
420 Westwood Plaza - 5th Flr., Los Angeles CA 90095