Vanderbilt University

Jason G Valentine

Hanyu Zheng

You Zhou

Cary L Pint

Richard Forsberg Haglund

Zhihua Zhu

Zachary J Coppens

Austin Howes

Adam P Cohn

A 2D spatial differentiator operates in transmission and comprises a Si Nano rod photonic crystal that can transform an image, Ein, into its second-order derivative, Eα∇E, allowing for direct discrimination of the edges in the image. The use of a 2D photonic crystal allows for differentiation and edge detection in all directions with a numerical aperture (NA) up to 0.315 and an experimental resolution smaller than 4 μm. The nanophotonic differentiator is able to be directly integrated into an optical microscope and onto a camera sensor, demonstrating the ease with which it can be vertically integrated into existing imaging systems. Furthermore, integration with a metalens is demonstrated for realizing a compact and monolithic image-processing system. In all cases, the use of the nanophotonic differentiator allows for a significant reduction in size compared to traditional systems, opening new doors for optical analog image processing in applications involving computer vision.

Flat optics for image differentiation

A 2D spatial differentiator operates in transmission and comprises a Si nanorod photonic crystal that can transform an image, Ein, into its second-order derivative, E&#x3b1; &#x2207;E, allowing for direct discrimination of the edges in the image. The use of a 2D photonic crystal allows for differentiation and edge detection in all directions with a numerical aperture (NA) up to 0.315 and an experimental resolution smaller than 4 &#x3bc;m. The nanophotonic differentiator is able to be directly integrated into an optical microscope and onto a camera sensor, demonstrating the ease with which it can be vertically integrated into existing imaging systems. Furthermore, integration with a metalens is demonstrated for realizing a compact and monolithic image-processing system. In all cases, the use of the nanophotonic differentiator allows for a significant reduction in size compared to traditional systems, opening new doors for optical analog image processing in applications involving computer vision.

A device according to one example of principles described herein may include a backplane, electrochemical actuator, and an optical resonator, wherein the electrochemical actuator is located between the backplane and optical resonator. Applied energy may be used to modify the volume of the electrochemical actuator material modifying the resonant/interferometric absorption, transmission, and reflection at visible and/or infrared frequencies.

Electrochemically actuated optical modulator

According to some aspects, a transmissive and all-dielectric optical component/limiter with great cutoff efficiency using Vanadium Dioxide (VO) as the active component is disclosed. In some embodiments, Vanadium dioxide is used for an optical limiter due to the large contrast in optical constants upon undergoing the semiconductor to metal phase transition. When triggered optically, this transition occurs within 60 fs, making the device suitable for an ultrafast laser environment. In addition, the phase transition threshold is tunable by applying stress or doping; therefore, the device cutoff intensity can be adjusted to fulfill specific requirements.

Growing community of inventors

Nashville, TN, United States of America

Jason G Valentine