DIGITAL IMPLEMENTATION OF A SHADOW MASK METHOD

An intensity speckle correlation method is implemented to digitally ob tain metrological information on test object deformation. It is based on the shadow mask concept, in which a negative of a recorded speckle pattern is repositioned oil its original place, so that no light is tr ansmitted. Any actual. alteration of the speckle pattern is monitored as light passing through the mask. In our proposal we use a Digital Sp eckle Pattern interferometric (DSPI) arrangement without a reference b eam. The technique is not phase sensitive, and the measured magnitude is the speckle intensity correlation. Experimental results are shown t o corroborate our assumptions.