METHOD, DEVICE AND MEDIUM FOR INFORMATION RECORDING AND REPRODUCING

摘要

PURPOSE:To enable recording with smaller energy and to enable simple reproducing by applying prescribed energy to an org. compd. having a polymorph structure to transit the compd. to other crystal polymorph and to execute recording and execute reproducing by a difference in the light absorption characteristic between the polymorphs. CONSTITUTION:The many polymorphs which differ slightly in the crystal structure exist in the org. compd. crystal and the structural change between the same is reversibly executed by impartation of the prescribed energy. The alphatype crystals in a thin alpha type crystalline film 2, in the case of copper phthalocyanine (Cu-Pc) are transited to the stable beta type polymorphs and the regions 6 of the beta type polymorphs are formed when electron beams 4 are projected from a light source 3 on said film. Information is thus recorded in the thin film 2 as the slight beta type regions 6. The transmission (reflection) of light is smaller in the regions 6 than the alpha type polymorphs and, therefore, this characteristic is utilized and the information is reproduced by detecting the transmitted or reflected light by a photodetector 8 or 10. The recording with the smaller energy and the simple reproducing are thus executed.