ECE Seminar Series

ECE Seminar

Title: Multi-Layer Phase Retrieval using Gated Wafefront
Speaker: C.S. Tan
Affiliation: Multimedia University, Malaysia
Day: Tuesday, October 28, 2014
Time: 4:00 pm - 5:00 pm
Location: Engineering B101

Abstract: A high power laser intensification model within a multi-layer coating material has been proposed. The Laser Induced Damage (LID) mechanism due to the thermal effect can be evaluated if the intensification and inter-layer/intra-layer defects/precursors are identified as well as the interlayer profiling. This talk will look into category (morphology) of LID as well as the surface measurement (with wavefront reconstruction) techniques that can be used to retrieve multilayer parameters. K. Nakagawa et. al. has achieved fs photography system (STAMP) that enable single shot time gated imaging system. With thin coating at about 200nm thickness, the inter-layer wavefront can be captured using a standard Shack-Hartmann technique. However, the multiple layers aberration (intra-layers) and distortion (inter-layers) has caused some wavefront distortion. An accurate absolute (reference free) estimation of multi-layers wavefront is needed. A correction is applied to compensate the distortion. An aberration reduction technique is proposed using multi-layer phase retrieval technique. The analysis will enhance the accuracy of overall growth prediction within the topological distribution of LIDs.

This is joint work with C. S. Menoni, M. Ritschard, E. K. P. Chong, and X. Wang.

Bio: Dr Ching Seong Tan serves as the Associate Professor in Multimedia University, Malaysia. He was also the recipient of J. William Fulbright Award 2012/2013. He is elected as the division head of my-CIE (International Commission of Illumination, Malaysia) in image technology.

Dr Tan received his first degree in 1998 at the University of Malaya. He then worked in Schlumberger (Drilling and Measurement) as the Drilling Services Engineer before joining NTU Singapore for his PhD in Engineering in 2002. Academically, he has served in various institutions as department head, research centre chair, and research team leader since 2005. He is a senior member of IEEE (the Institute of Electrical and Electronics Engineers), member of SPIE (International Society of Optical Engineering) and Chartered Engineer (Institute of Mechanical Engineer, UK).