Publications & Presentations

Broadband, High-Efficiency, Large-Aperture Metalenses in the Visible

David Woolf, Joe Goodwin, Joel Hensley (PSI), Jonathan Fan, Anton Ovcharenko, Mingkun Chen, Peter Phan (Stanford)
OSA Optical Design and Fabrication Congress
27 June 2021 – 01 July 2021
OSA Virtual Event
Flat Optics and Metasurfaces III (FTu2C)

We developed a design for a high efficiency, broadband metalens
–Used a heuristic approach, based on mature diffractive optic design methods
–> 90% transmission efficiency in each of the red, green and blue color bands
–Maintains performance out to > 10 10°AOI

•Metalens can be used to correct aberrations in multi element optical systems
–Corrective doublets

Acknowledgement of Support and Disclaimer
This material is based upon work supported by the Defense Advanced Research Projects Agency (DARPA) under Contract No. 140D0420C0065. Any opinions, findings and conclusions or
recommendations expressed in this material are those of the author(s) and do not necessarily reflect the views of the Defense Advanced Research Projects Agency (DARPA); or its Contracting Agent, the U.S. Department of the Interior, Interior Business Center, Acquisition Services Directorate, Division III.
This material is based upon work supported by the DARPA STTR Program Office under Contract No. W31P4Q-21-C-0031. Any opinions, findings and conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the views of the DARPA STTR Program Office.

Flight Demonstration of a Laser Hygrometer Payload for the ScanEagle UAS

D. Sonnenfroh, S-J. Chen, and M. Zondlo
Paper A02107, Unmanned Systems in Atmospheric Research I
American Geophysical Union Fall Meeting (Virtual)
7 December, 2020

  • Detailed cloud macro and microphysical properties remain a challenging measurement goal.
  • Enhanced knowledge of these properties is needed to increase understanding of various cloud processes, including entrainment and droplet growth, that are important in both weather
    forecasting and climate change.
  • Water vapor gradients affects droplet growth rates and, together with temperature, are needed for determination of supersaturation values.
  • High sensitivity, high accuracy measurements of water vapor and temperature are needed at high spatial resolution, and therefore at high measurement rate
  • High Yield and Economical Production of Rare Earth Elements from Coal Ash

    Physical Sciences Inc., Andover, MA; Center for Applied Energy Research, Lexington, KY; and Winner Water Services, LLC, Sharon, PA
    Presentation to: Rare Earth Elements (REE) Program Portfolio, 2021 Annual Review Meeting (Virtual), 25 May 2021

    Plant located at KY ash landfill site: ~ 300 m x 300 m footprint, includes physical and chemical processing plants as well as ash feedstock delivery, preparation, and staging operations

    Visualizing and Quantifying Methane and Natural Gas Emission using Lasers and Small Semi-autonomous Drones

    Michael B. Frish
    OSA Imaging and Applied Optics Congress/OSA Optical Sensors and Sensing Congress
    Vancouver, British Columbia Canada
    22 June 2020 - 26 June 2020

    We describe man-portable and aerial near-IR laser sensor platforms which spatially scan a laser beam to create quantitative plume images. These tools locate, visualize, and deduce natural gas (methane) emission rates at small infrastructure sources.

    Dual-mode endoscopic probe combining OCT and autofluorescence imaging for inner ear hearing loss diagnosis and therapy guidance

    Jesung Park, Jeffrey Cheng, Daniel Lee, Jeffrey Holt, Hannah Goldberg, Gopi Maguluri, John Grimble, and Nicusor Iftimia
    SPIE Photonics West/BIOS 2020
    San Francisco, CA
    February 1, 2020

    Proof of Concept study has demonstrated that the combined OCT/AF imaging approach can detect morphological and biochemical changes related to inner ear SNHL.

    OCT/AF technology could be used to diagnose potential causes of SNHL and evaluate the success of the hair cell regeneration therapy approaches.