New Developments in Laser Speckle Strain Measurement Techniques

Non-contacting strain measurements of small specimen or materials testing under high temperature conditions today are of increasing importance in material science and modern technologies like micromechanics and microelectronics. Optical methods without needs of surface marking or sample preparation exhibit major advantages for material testing in these expanding fields. We show two new non-contacting strain sensors, based on the laser speckle correlation technique.