Abstract: A CCD, a computer and a traditional microscope are combined to realize the non-destructive microscope observation of specimens. The hardware and the software of the system are introduced, with focus on the assessment of image definition and the key algorithm of image reconstruction, and VC++ program is used to validate and implement. The definition evaluation function is specified by gray variance algorithm, and the definition of the image is indicated by gray variance. The non-destructive analysis instrument collects a lot of images of the specimen in different distances by moving the plate controlled by accurate mechanism. It finds the clear parts of the image by using definition evaluation function, and synthesizes them into a complete clear image.