Clark School Home UMD

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

University of Maryland School of Engineering Announces Unprecedented Investment from A. James & Alice B. Clark Foundation

Alumnus Xiaobo Tan named Withrow Distinguished Scholar at Michigan State

Alumnus Profile: Jameel Francis

Papamanthou Gives Keynote at FAB 2018

Electrical and Computer Engineering Wins 2018 Alumni Cup

Improving speech intelligibility testing with new EEG methods

Clark School Researchers Recognized for Exceptional Inventions

The Clark School Celebrates Women's History Month

News Resources

Return to Newsroom

Search News

Archived News

Events Resources

Events Calendar

Additional Resources

UM Newsdesk

Faculty Experts