Compact Laser Speckle Shearography System Based on High Resolution MQW Detection Technology

Full field, Shearographic NDE provides real time imaging capabilities but at the expense of poor resolution. To address this need, Rice Systems, Inc. proposes the development of a unique Semiconductor High Resolution IMaging Shearography System (SHRIS) for assessing the effects of evolving damage in critical components, using the recently developed Photorefractive Multiple-Quantum-Well (PMQW) devices. In recent years, PMQW devices have attracted much attention for real-time image processing applications. These materials are two-dimensional high resolution imaging devices without pixellation. Though Shearography has the capability of imaging effects of stress and fatigue, such as corrosion, delaminations, and impact damage, conventional instrumentation relies on CCD-based imaging, which provides only 20 micron resolution. However, to be able to detect evolution of damage of critical components, higher resolution recording devices are needed. PMQW devices have been demonstrated as a real-time holographic material capable of recording holograms with a resolution of 2.5 microns at frame rates as high as 600 kHz. SHRIS would combine the success of ShearographiC NDE with semiconductor-based imaging to produce real time, full field NDE, with up to 8 times higher resolution than conventional CCD camera systems. Phase I will establish feasibility and design specifications for Phase II development of commercially viable instrumentation. The higher resolution, and therefore the more efficient inspection offered by this system would translate into improved safety and reliability, and the reduced maintenance costs for aging critical machinery components.