Film comprising a soluble conjugated polymer and an organic pigment and/or organic dye is prepd. by dissolving the polymer in an organic solvent, dissolving or dispersing the organic pigment and/or organic dye into the polymer soln. and coating the soln. or dispersion on a base board.    The soluble conjugated polymer is a polyalkylthiophene (e.g., poly-3-propylthiophene, poly-3-hexylthiophene, poly-3-octylthiophene, 3-hexylthiophene/thiophene copolymer, 3-laurylthiophene/thiophene copolymer, 3-dodecylthiophene/3-propylthiophene, etc.), polyalkylpyrrole (e.g., poly-3-propylpyrrole, poly-3-hexylpyrrole, poly-3-laurylpyrrole, 3-dodecylpyrrole/pyrrole copolymer, 3-laurylpyrrole/pyrrole copolymer, 3-dodecylpyrrole/3-propylpyrrole copolymer, etc.) or polyalkylaniline (e.g., poly-N-propylaniline, polyN-dodecylaniline, N-dodecylaniline/aniline copolymer, N-laurylaniline/aniline copolymer, N-dodecylaniline/N-propylaniline copolymer, etc.). The colourant is, e.g., a phthalocyanine cpd. (e.g., metal phthalocyanine, metal-free phthalocyanine, etc.), naphthocyanine, an azo cpd. (e.g., mono-, bis or tris-azo cpd., etc.), perylene cpd. (e.g., perylene acid anhydride, perylene acid imide, etc.), polycycloquinone cpd. (e.g., anthraquinone deriv., violanthrone deriv., isoviolanthrone derivs., etc.), indigo deriv. (e.g., indigo deriv., thioindigo deriv., etc.), carbonium cpd. (e.g., diphenylmethane, triphenylmethane, xanthene, acrydine, etc.), quinone imine cpd. (e.g., azine, oxazine, thiazine, etc.), methine cpd. (e.g., cyanine, azomethine, etc.), quinoline cpd., benzoquinone, naphthoquinone, naphthalimide cpd., bisbenzoimidazole deriv., etc. The organic solvent is e.g., chloroform, tetrahydrofuran, anisole, heptane, toluene, etc. The film is prepd. by casting, spin coating, Langmuir-Blodgett process, etc.    USE/ADVANTAGE -   The film is used as an optoelectric conversion element sensitive over wide wavelength range and having high conversion efficiency. It is used in solar cells, photosensors, optical sensors, electrophotographic materials, optical recording materials, etc.    .D