| 摘要 |
PROBLEM TO BE SOLVED: To suppress the rapid increase in jitter when repeated recording is made from several times to several tens of times. SOLUTION: A first dielectric layer 3, a signal-recording layer 4, a second dielectric layer 5, a light reflection layer 6, and a protection film layer 7 are successively laminated on a substrate 2 for formation. The signal-recording layer 4 is formed by GeSbTe material, and at the same time the diameter of a crystal particle being generated at the rear end part of a recording mark formed according to a recording signal for the signal-recording layer 4 is set to 50 nm or less. |
