| 摘要 |
PROBLEM TO BE SOLVED: To execute coloring and information recording by an excitation light source with a light power limited more than in a conventional manner by having a modulated light beam being perpendicular polarization in which a thermal excitation laser beam is the same direction as the perpendicular polarization in the vibration direction of an electric field component, and an incidence angle being an angle of polarization determined from the surface layer. SOLUTION: Since the protection layer 8 of a surface layer has high permeability; however, also has an excellent surface property like as a mirror surface, its reflection conforms to Fresnel's law comprising a regular reflection component 12 and refracted incident light 13, and most of the incident lights not satisfying a polarization condition reflects in a polarized manner in the direction of regular reflection. Herein, by making the incident lights in linear polarization and the vibration direction of the electric field component in the same direction as the perpendicular polarization; furthermore, making an incident angle with a polarization angle ψdetermined by a reflection rate of the protection layer 8, a great part of the incident laser beams can be taken in refraction in the interior of the protection layer 8. If the refractive indexes of the protection layer 8 and thermal recording layer 9 are the same, reflection can be restrained on the protection layer and thermal recording layer interface, thus obtaining high efficient light and heat conversion and coloring efficiency. |
