Xiangzhi Yu, PhD student in Mechanical Engineering, will defend his dissertation work Wednesday, November 11 at 9:30 AM (today!!!). His PhD work is on Multi-Degree of Freedom Optical Metrology Techniques. We wish Xiangzhi well during his presentation and defense.
Papers by Chen Wang and Bill Green have appeared in their final form online. Chen’s paper, Data Age Error Compensation for Nonconstant Velocity Metrology, was recently accepted in IEEE Transactions on Instrumentation and Measurement. Bill’s paper, with a PhD student James Corsetti from Optics, was recently accepted and published by Applied Optics. This paper is on Simultaneous interferometric measurement of linear coefficient of thermal expansion and temperature-dependent refractive index coefficient of optical materials. Links to both papers can be found on the publications page. Nice job and congratulations!
Bill Green, Mechanical Engineering Undergraduate Student, has had a paper accepted as a co-author by Optical Engineering. This is Bill’s first time co-authoring a paper. Additionally, Bill will be presenting his work on thermal expansion and dn/dT metrology at the upcoming ASPE Annual Meeting in Portland, OR. When the final version is published and online, we’ll be sure to update.
Xiangzhi Yu and Chen Wang both have had first author publications accepted recently. Chen’s paper is Data age error compensation for non-constant velocity metrology, which advances his previous work on data age error to arbitrary orders. This paper has been accepted into IEEE Transactions on Instrumentation and Measurement. More details will be posted when available.
Xiangzhi had two 1st author papers published. His first is with Dr. Tieli Zhang, a former visiting scientist in the group from the Beijing Aerospace Institute for Metrology & Measurement Technology, on Absolute air refractive index measurement and tracking based on variable length vacuum cell. This work was supported by NIST and the paper was published in Optical Engineering. Xiangzhi’s second paper was with co-authors Dr. Steven Gillmer (now at MIT Lincoln Labs) and Dr. Shane Woody (InSituTec, Inc.) and was published in Review of Scientific Instruments. This work was on the Development of a compact, fiber-coupled, six degree-of-freedom measurement system for precision linear stage metrology with research support from NIST and NSF.
Congratulations to both students and the rest of their team! Well done!
Mechanical Engineering MS student Mike Ricci successfully defended his MS Thesis. His work, Opto-Mechanical Design of a Three-Degree-of-Freedom Homodyne Interferometer for Freeform Optics Metrology, was part of research within the Center for Freeform Optics. His thesis, once finalized, will be available for viewing under the downloads section.
Mike is now off to Quartus Engineering to work on opto-mechanical design for the aerospace industry. Congratulations Mike and we wish you all the best!
Steve Gillmer successfully defended his PhD Thesis, Resolution and Functionality Enhancements in Optical Metrology, this past semester. Steve has worked hard over the past few years and has broadened his expertise to metrology, instrumentation, signal processing, and controls. Steve’s thesis can be accessed on the Downloads page. Steve is off to MIT Lincoln Laboratory and we wish him all the best.
Steven Gillmer, MechE PhD Student, will be defending his PhD work on Tuesday, April 26th at 10:00 AM. The defense will take place in Hopeman 224, in the MechE Conference Room.
Resolution and Functionality Enhancements in Optical Metrology
Scientific experiments continue to push engineering limits beyond the nano-scale, driving the development of extremely high resolution measurement tools and calibrations as a result. The effective implementation of optical metrology and its associated instrumentation involves a multi-disciplinary approach. This thesis draws from mechanical, electrical, and optical engineering subject areas in order to implement the proposed resolution and functionality enhancements. The discussion will focus on three forms of optical metrology: optical displacement sensing, scatterometry, and interferometric weak measurements. The primary applications of the advancements in optical displacement sensing lie in the measurement and calibration of computer numerical control (CNC) equipment and coordinate measuring machines (CMMs). A novel scatterometry tool will be presented for critical-dimension metrology in the continued sustenance of Moore’s law. Finally, optical displacement sensing and scatterometry will find parallels through weak measurements. Both application areas have potential for vast performance improvements via the measurement of a weak value. A variety of novel concepts and experiments will be presented within these fields of research with the ultimate goal of their dissemination into the manufacturing and semiconductor industries.
Sam Butler successfully defended his MS Thesis, Development of Electronics and Signal Processing for a Displacement Measuring Interferometer Probe for Freeform Optics, on April 14th. Sam’s committee consisted of his advisor, Professor Paul Funkenbusch (MechE), and Professor Qiang Lin (ECE).
Sam has recently accepted a position as a System Engineer at Clerio Vision, Inc., a startup company spun off from the University of Rochester and the labs of Prof. Ellis, Knox, and Huxlin. We wish Sam congratulations and all the best in the future!
Mechanical Engineering MS student, Sam Butler, will defend his MS thesis work on Thursday, April 14th at 3 PM in the Hopeman 224 conference room.
Development of Electronics and Signal Processing for a Displacement Measuring Interferometer Probe for Freeform Optics
The burgeoning field of freeform optical design is currently limited by metrological techniques for validating manufactured designs. State-of-the-art measurement systems do not provide the flexibility, measurement bandwidth, or low measurement uncertainty required for producing freeform optics of the same quality achievable for spherical and aspheric parts. One promising avenue for reaching high-quality metrology is through the use of optical coordinate measuring machines (OCMM). These are 5-axis probing machines that use non-contact, optics-based probes for surface measurement. This research seeks to develop an optical probe with high measurement bandwidth and low measurement uncertainty in a compact form factor that provides linear and angular measurement of the optical surface under test. The probe uses homodyne interferometry in a Michelson configuration for linear displacement sensing, and a lens in combination with a position-sensitive detector in an autocollimation capacity for angular displacement sensing. Development of electronics and signal processing, as well as preliminary measurement results using a prototype probe, will be discussed.
Professor Ellis recently met with Professor Jui-Wen Pan and Dr. Kao-Der Chang who were on a visit to The Institute of Optics Industrial Associates Program from Taiwan and discussed methods for transitioning technology from the university environment to relevant industries. Professor Pan is an Assistant Professor in the Institute of Photonic System at the National Chiao Tung University. Dr. Chang is a Researcher at the Industrial Technology Research Institute (ITRI) in their Mechanical and Systems Research Laboratory. We look forward to potential collaborations in the future!