Clark School Home UMD
ECE

ECE News Story

Krishnaprasad Research Team Receives Patent for Wavefront Sensors

Krishnaprasad Research Team Receives Patent for Wavefront Sensors

Professor P.S. Krishnaprasad (ECE/ISR), ISR Research Professor Mikhail Vorontsov, ISR Assistant Research Scientist Eric Justh, Dr. Leonid I. Beresnev (Army Research Laboratory), and Dr. Jennifer Ricklin (Army Research Laboratory) have been awarded U.S. Patent 6,911,637 for “Wavefront phase sensors using optically or electrically controlled phase spatial light modulators.”

These systems and methods for optical wavefront sensing and control are based on a phase-contrast Fourier-domain filtering technique. Wavefront phase sensing is accomplished using an optically or electronically controlled phase spatial light modulator (SLM) as a Fourier-domain filter. Examples of optically controlled phase SLMs include (1) liquid crystal light valve (LCLV); (2) micro-electromechanical system (MEMS) micromirror array used in conjunction with a photodetector array; and (3) pixelized liquid-crystal device used in conjunction with a photodetector array.

The direct adaptive optic feedback system approach is capable of high-resolution real-time correction of atmospheric turbulence-induced wavefront phase aberrations. The disclosed wavefront sensors could be used with conventional low-resolution adaptive-optic wavefront correction hardware based on deformable mirrors or multi-electrode wavefront phase modulators.

The invention also includes a wavefront sensor, the "Differential Zernike Filter." This device uses the difference between two intensity measurements corresponding to equal but oppositely-directed zero-order spectral component phase shifts to produce a high visibility wavefront sensor output that is particularly well-suited for use in the direct adaptive optic feedback system.

July 18, 2005


Prev   Next

Current Headlines

UMD Team Selected to Participate in International Solar Decathlon

Espy-Wilson Delivers Keynote Address for Stanford’s WISE Inspirations Network

Hubbard Elected to the National Academy of Engineering

Khaligh is General Chair of 2016 IEEE APEC Conference

UMD-led Team Advances in SpaceX Hyperloop Pod Competition

UMD Accepted to DOE’s 2017 Solar Decathlon Competition

Dumitras Chairs Conference Session on Emerging Cyber Threats, Novel Attacks

Alum Xiaobo Tan named 'Foundation Professor' at Michigan State

News Resources

Return to Newsroom

Search News

Archived News

Events Resources

Events Calendar

Additional Resources

UM Newsdesk

Faculty Experts