报告题目:Investigationof Precision Molding of Chalcogenide Glass Optics
报告人:Dr. Lin Zhang,The Ohio State University
Chalcogenide glass (ChG) is increasingly used ininfrared (IR) optical systems owing to its excellent IR optical properties andscalable production using precision glass molding (PGM). This study is aimed toseek scientific and fundamental understanding of ChG in precision glass moldingprocess for precision IR micro-optical fabrication by prediction of opticalproperties transition, integrating numerical modeling of forming process, andevaluation of the molded freeform optics. Compared with conventional IRmaterials, germanium-free ChG can be readily molded into precision optics,therefore, providing photonics industry with material candidates for low-costand high-performance photonics devices.Before widely applications in industry, the major challenges inmanufacturing affordable high-quality molded optics, the proposed work willinclude several key steps:
1. Evaluate the thermoforming mechanism of ChG inPGM. The refractive index variations inside large-aperture IR lenses arepredicted by FEM simulation and further evaluated by measuring wavefrontchanges using an infrared Shack-Hartmann wavefront sensor (SHWFS), while theresidual stresses trapped inside the molded lenses were obtained by using abirefringence method.
2. ChG molded micro-optical device fabrication anddemonstration. Two typical micro-optical devices are designed and fabricated,including SHWFS based measurement system for evaluating the molded freeformlenses and multi-channel large field-of-view IR artificial compound eyes.
Lin ZHANG is currently pursuing aPh.D in integrated industry engineering under the advisement of Professor AllenY. Yi. His work focuses on the mechanism of precision chalcogenide glassmolding and its applications on thermal imaging. Infrared camera thermalimaging is an exciting technology that allows the user to ‘see’ heat energywith a device similar (in operation) to a standard camcorder, which expands the‘visible’ spectrum of the human eye by doing the work our eyes cannot do. Ithas numerous practical applications, including night vision imaging and thermaldetection. Lin has designed and fabricated serval microlens arrays usingprecision glass molding that dominated the possibility of such method andfurther enlarged the applications of thermal imaging. Compared to currentindustry standards, precision glass molding is more suitable for large-volumeand low-cost industrial production. Lin has published over 40 technicalarticles, including more than 35 SCI journal articles and 5 patents.