Liquid Crystals and a 35-Year Journey from Information Displays
to Laser Fusion and Beyond
Liquid crystal (LC) technology has experienced explosive growth from its humble origins as an unimportant laboratory curiosity discovered by Friedrich Reinitzer in 1888 to today’s multibillion dollar information display industry spawned by the invention of the twisted nematic LC display in the 1970s. The inherent anisotropy in their optical and physical properties and the ability to tune these properties through molecular design and chemical synthesis, along with cost-effective device manufacturing scalability, high optical quality and contrast, electrical and optical addressability, and remarkably high laser-damage resistance, all contribute to the importance of LC’s for demanding applications in optics and photonics. A singularly significant example is the application of LC materials in passive circular polarizers and wave plates for beamline polarization control in the 60-beam, 40-TW OMEGA Nd:glass laser system at the University of Rochester’s Laboratory for Laser Energetics (LLE). This solid-state glass laser system, used to support the U.S. Department of Energy’s Inertial Confinement Fusion (ICF) and High-Energy-Density (HED) physics research missions, contains more than 365 large-aperture (100- to 200-mm) LLE-fabricated LC devices that represent a 30-year track record of proven performance for the technology. Many of these LC devices have been in continuous service on OMEGA for over 15 years without suffering degradation in their performance.
Following a brief introduction to structure–property relationships in LC materials, an account of the history and events that led to the development of passive LC optics for OMEGA will be presented, along with an overview of past and current LLE research to develop active and passive LC optics (tunable/switchable polarizers, optical modulators, polarization rotators and converters, beam deflectors, and amplitude shapers) and high-performance LC materials for tabletop and high-peak-power laser applications. A view of the road ahead leading to new applications frontiers for next-generation LC materials and devices currently under development will also be shared.
This material is based upon work supported by the Department of Energy National Nuclear Security Administration under Award Number DE-NA0001944, the University of Rochester, and the New York State Energy Research and Development Authority. The support of DOE does not constitute an endorsement by DOE of the views expressed in this presentation
Mr. Kenneth L. Marshall has been involved in the design and development of liquid crystal materials and devices since 1972. He joined LLE in November of 1984, following 12 years of industrial experience in LC materials design, synthesis and LCD manufacturing under the direction of the late James L. Fergason, the inventor of the twisted nematic LC display technology. As a Senior Research Engineer, Mr. Marshall directs and conducts research in organic optical materials and liquid crystals for applications in optics, photonics and high-peak-power lasers, and served as Acting Group Leader for Optical Materials Technologies from July 2014 to May 2017. He has authored over 60 publications, holds over 10 patents, serves as a peer reviewer for numerous journals in optics, physical chemistry and liquid crystals, has conducted LC materials and device research under contract to the US Army, Navy, and Air Force, and has been a consultant for numerous companies including Corning, Inc., Physical Optics Corp, Zygo Corp, and Eastman Kodak Company. Mr. Marshall is a Senior Member of both SPIE and OSA, and a member of both the Society for Information Display (SID) and the American Chemical Society.