Coherent Information Processing Of White Light Speckle Sandwich

A sandwich technique is presented. Two white light speckle patterns corresponding to the two different loading states of the structure are recorded. Analysis can be carried on in the Fourier transformation optical system as well as the point diffraction optical system. The coherent conditions of the speckle sandwich patterns are derived. The mismatch of the two corresponding speckle patterns can be made use of to introduce the linear photo-carrier with which the sensitivity and accuracy of the white light speckle are improved, meanwhile the measurement scale is enlarged.