LASER SPECKLE INTERFEROMETRIC MICROSCOPE

NOVA TECHNOLOGY, INC. IS INVESTIGATING THE USE OF AN OPTICAL SETUP SIMILAR TO A TWYMAN-GREEN INTERFEROMETER, A LASER BEAM TO ILLUMINATE A MICROSCOPE SPECIMEN AND A REFERENCE SURFACE, IN THE SCATTERED LIGHT FROM THE SPECIMEN IS MIXED WITH THE SCATTERED LIGHT FROM THE REFERENCE SURFACEAT THE IMAGE PLANE OF THE MICROSCOPE. BY MONITORING THE SPECKLE INTENSITY WITH A CCD ARRAY, THE PHASE CHANGE IN SPECKLE IS DETECTED FOR SURFACE DISPLACEMENT MEASUREMENT. INTERMITTENTLY THE REFERENCE ILLUMINATION IS BLOCKED OFF SO THAT SURFACE DEFORMATION CAN BE MAPPED USING A SPECKLE PATTERN CORRELATION TECHNIQUE. IN ADDITION, THE MICROSCOPE CAN BE ILLUMINATED BY AN INCOHERENT LIGHT SOURCE FOR CONVENTIONAL IMAGING. THE IMAGES FROM THREE DIFFERENT OPERATING MODES ARE THEN PROCESSED AND INTEGRATED FOR DISPLAY.