Linear displacement measuring device and method based on Young's double-slit interference fringes

The invention provides a linear displacement measuring device and method based on Young's double-slit interference fringes. The linear displacement measuring device comprises a double-slit diaphragm, a linear array camera, a displacement measuring sliding platform, a light source and an image processing system. The displacement measurement sliding platform is a sliding table moving at the linear guide rail, the sliding table is located at the position of a measured object, and the sliding table is connected with the linear array camera, so that the optical axis of the camera, laser output by the light source and the double-slit diaphragm are located at the same horizontal height; when measurement operation is carried out, light source laser passes through the double-slit diaphragm to form interference fringes; the linear array camera collects the interference fringe image and transmits the collected data to the image processing system; the sliding table drives the linear array camera to perform horizontal lin