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

Gang Qu delivers keynote address on fault tolerance and the Internet of Things

Reza Ghodssi named ASME Fellow

Two Maryland SOFC projects selected by the Department of Energy

Ghodssi, Beyaz, Waits issued US patent for microgenerator

Alumnus Xiaobo Tan promoted to full professor at Michigan State

MC2 Researchers Receive $1.2M NSF Grant for Verifiable Computation

Jonathan Simon is invited speaker at CHScom 2015

Reza Ghodssi named AVS Fellow

News Resources

Return to Newsroom

Search News

Archived News

Events Resources

Events Calendar

Additional Resources

UM Newsdesk

Faculty Experts