NOVELTY - A fluorene copolymer-containing thiophene and thiophene pyrroledione unit (I) is new.    USE - Fluorene copolymer-containing thiophene and thiophene pyrroledione unit used for organic solar battery device, organic electroluminescence device and organic field effect transistor (claimed).    ADVANTAGE - The copolymer can form very strong donor-receptor structure, improves stability of material, and reduces energy band gap of material to expand the sunlight adsorbing range and improve photoelectric conversion efficiency.    DETAILED DESCRIPTION - A fluorene copolymer-containing thiophene and thiophene pyrroledione unit of formula (I), is new.    R1, R2, R3=H or 1-20C alkyl;    x+y=1;    x, y=greater than 0;    n=1-200;and    Ar'=thiophene unit.    INDEPENDENT CLAIMS are included for:    (1) a preparation of (I);    (2) an organic solar battery device comprising substrate base material, conductive layer deposited on one surface of the substrate base material as anode, poly(3,4-diethyoxyl thiophene) coated on conductive layer for modifying; poly(styrene sulfonic acid) layer coated on poly(3,4-diethyoxyl thiophene); active layer on surface of poly(styrene sulfonic acid) layer, and metal aluminum layer arranged on surface of active layer as cathode; material of active layer including electronic donor material and electronic receptor material; electronic receptor material comprising (6,6) phenyl-61C-methyl butyrate; electronic donor material comprising fluorene copolymer;    (3) an organic electroluminescence device comprising substrate, conductive layer deposited on one surface of substrate as anode, luminous layer coated on conductive layer, buffer layer coated on luminous layer with lithium fluoride as material and metal aluminum layer arranged on buffer layer as cathode;and    (4) an organic field effect transistor comprising doped silicon slice, silicon dioxide (SiO2) insulating layer, octadecyltrichlorosilane layer for modifying SiO2, organic semiconductor layer coated on octadecyltrichlorosilane layer, source electrode and drain electrode arranged on organic semiconductor layer at intervals.