NOVELTY - An optical element (5) producing method involves forming a bonding film (3) on a surface of an optical component (2) by plasma polymerization, where the bonding film includes an silicon skeleton having a random atomic structure including a siloxane bond and leaving groups bound to the silicon skeleton. The energy is applied to the bonding film to eliminate the leaving groups from the silicon skeleton at a surface of the bonding film so as to provide adhesive properties. The optical component (2) and an optical component (4) are bonded via the bonding film.    USE - Method for producing an optical element (claimed) such as optical lens, diffraction grating, optical filter and protection plate, photoelectric conversion elements such as solar cell, optical storage media such as optical disk, and display elements such as LCD element, organic electroluminescent element and electrophoretic display element.    ADVANTAGE - The method enables producing the optical element in a simple, rapid and reliable manner with high light induced damage resistance, high size precision, and high light transmission properties by bonding the optical components via the bonding film. The optical element has excellent thermal resistance and chemical resistance properties, bonding strength and mechanical strength.    DETAILED DESCRIPTION - An optical element producing method involves forming a bonding film on a surface of an optical component (2) by plasma polymerization, where the bonding film includes a silicon skeleton having a random atomic structure including a siloxane (Si-O) bond and leaving groups binding to the silicon skeleton. The energy is applied to the bonding film to eliminate the leaving groups from the silicon skeleton at a surface of the bonding film so as to provide adhesive properties. The optical component (2) and an optical component (4) are bonded via the bonding film, where the optical elements (2, 4) have light transmission properties. Refractive index of the bonding film is adjusted to be approximately the same as a refractive index of two optical components by adjusting a film forming condition of the plasma polymerization. An INDEPENDENT CLAIM is also included for an optical element.    DESCRIPTION OF DRAWING(S) - The drawing shows a longitudinal sectional view illustrating a method for producing an optical element.    Optical components (2, 4)    Bonding film (3)    Optical element (5)