| 摘要 |
PURPOSE:To substantially prevent the breakage of recorded information even when the medium receives large impact by providing a cartridge with an outside wall forming an outside shape and an inside wall for limiting the moving range in the surface direction of an optical disk and forming the inside wall thinner than the outside wall. CONSTITUTION:The thickness of the inside wall is reduced or the inside surface of the inside wall is recessed or a projecting part is provided near the center of the optical disk to limit the moving range in the surface direction by this projecting part. For example, the optical disk 1 is mounted to the cartridge 2 which is made of polycarbonate, has the outside wall 3 of 1mm thickness, the inside wall 4 of 0.5mm thickness, a window 5, and a moving hole, and is equipped with a stainless steel shutter 6. Since the inside wall 4 is small in thickness in this case, the buffer effect to absorb the impact when the optical disk 1 comes into collision against the inside wall 4 by falling, etc., is large and the breakage of the information by the peeling of the optical disk 1 is substantially prevented. |
