| 摘要 |
PROBLEM TO BE SOLVED: To prevent unnecessary disturbance on a user caused by the appearance of a product similar to a music compact disk by coloring an optical information recording medium for recording main information on an information track and identifying the usage of the main information. SOLUTION: For a music clock CD, music is reproduced by a usual CD player, but when reproducing is performed by the music clock CD, the function of the player is put into full play. For example, by coloring the music clock CD black, usage is identified by eyes because the usual CD is transparent. Also, by detecting the color of the music clock CD by a detecting means, second mode reproducing is selected. Thus, a user reads the color of an optical information reproducing device by eyes to identify the usage of main information, for example the music clock CD. |
