Optical data recording disc with protrusion between clamping area and center hole
OwnerKazuhiro HAYASHI, Eiji Ohno +1inventors
InventorsKazuhiro HAYASHI, Eiji Ohno, Masanari Mohri
Life of this patent
Estimating the term…
Abstract
A disc-shaped optical data recording medium has a signal recording layer for reading and/or writing data using light, and a 10 μm to 200 μm thick transparent protective layer disposed over the signal recording layer. The optical data recording medium includes a protrusion projecting from a surface of the transparent protective layer on a light-incidence surface side to which light is emitted to the signal recording layer. The protrusion is disposed in an area between a center hole and a clamping area where the optical data recording medium is held when reading and/or writing data in the signal recording layer.
Claims6
An optical data recording medium having a signal recording layer for reading and/or writing data, and a transparent protective layer disposed over the signal recording layer, the optical data recording medium comprising:
- a protrusion projecting from a surface of the transparent protective layer on a light-incidence surface side to which light is emitted to the signal recording layer,
- the protrusion disposed in an area that is located between a center hole of the optical data recording medium and a clamping area where the optical data recording medium is held when reading and/or writing data in the signal recording layer,
- a diameter of the center hole being 15.0 mm,
- the protrusion being located between 17.5 mm diameter and 22.0 mm diameter,
- a height of the protrusion measured from a surface of the transparent protective layer being 0.3 mm or less.
A manufacturing method for manufacturing an optical data recording medium, comprising:
- forming a signal recording layer for reading and/or writing data,
- forming a transparent protective layer disposed over the signal recording layer, and
- forming a protrusion projecting from a surface of the transparent protective layer on a light-incidence surface side to which light is emitted to the signal recording layer,
- wherein the protrusion is formed in an area that is located between a center hole of the optical data recording medium and a clamping area where the optical data recording medium is held when reading and/or writing data from/onto the signal recording layer,
- a diameter of the center hole being 15.0 mm,
- the protrusion being located between 17.5 mm diameter and 22.0 mm diameter,
- a height of the protrusion measured from a surface of the transparent protective layer being 0.3 mm or less.
Dependencies are inferred from the claim text.