| 摘要 |
A multi-layer optical information recording medium has a first information layer (7) located at the incident side for a laser beam and another information layer (17) at the back thereof. Thus, it has a large capacity. A relationship that R1a < R1c and R2a > R2c holds for the reflectances R1a and R1c of the information layer (7) in a recorded portion and in a non-recorded portion, and the reflectances R2a and R2a of the information layer (17) in a recorded portion and in a non-recorded portion. A relationship that A1a < A1c holds between the absorptances A1c and A1a of the first information layer in the crystalline state and in the amorphous state. Similarly, a relationship that A2a < A2c holds between absorptances A2c and A2a of the second information layer in the crystalline state and in the amorphous state. Thus, signals can be written to the recording medium at a fast speed and at high sensitivity. <IMAGE> |
