NOVELTY - Preparing stripe structure on conjugated polymer surface comprises (i) preparing conjugated polymer thin film with conductive glass surface, placing the polymer film in a sample chamber set with an optical transparent window and fixing the polymer film on a moving platform; (ii) expanding a pulse laser beam, focusing the expanded pulse laser beam and emitting the linear beam to the surface of the polymer film; (iii) controlling the laser output energy; and (iv) moving the sample chamber by utilizing the moving displacement platform and thus forming periodic micro-grating structure.    USE - The stripe structure is useful for liquid crystal display device and polymer solar cell modules.    ADVANTAGE - The stripe structure is provided with submicron and nano size resolution ratio.    DETAILED DESCRIPTION - Preparing stripe structure on conjugated polymer surface comprises (i) preparing conjugated polymer thin film with conductive glass surface by electrochemical method, placing the polymer film in a sample chamber set with an optical transparent window and fixing the polymer film on a precise electric-control three-dimensional moving platform; (ii) expanding a pulse laser beam, focusing the expanded pulse laser beam to form a linear beam through a cylindrical lens, and emitting the linear beam to the surface of the polymer film; (iii) controlling the laser output energy so that the energy density of a coherent part is less than the energy density threshold required for polymer melting; and (iv) moving the sample chamber by utilizing the moving displacement platform and thus forming periodic micro-grating structure with polymer film surface which is irradiated by the beam. An INDEPENDENT CLAIM is also included for a device for preparing surface relief stripe structure on conjugated polymer surface through pulse lasers, comprising a sample chamber set with a transparent window, a polymer film placed inside the chamber, a vacuum and inert gas protection environment is formed inside the chamber, a light beam shaping and focusing element for shaping and focusing the laser beam spot into a linear shape and irradiating the polymeric film surface, and a control system for controlling the laser beam on the polymer film surface for grating and scanning to form a stripe structure.