Recording medium, and playback apparatus and method, production apparatus and method and recording apparatus, for same
a technology which is applied in the field of recording medium and playback device and method, production apparatus and method and recording device, for the same, can solve the problems of insufficient copyright protection of digital data and insufficient payment of copyrighters for digital data, and achieve the effect of superior quality
- Summary
- Abstract
- Description
- Claims
- Application Information
AI Technical Summary
Benefits of technology
Problems solved by technology
Method used
Image
Examples
first embodiment
[0152 of the Disk-Shaped Recording Medium
[0153]In this embodiment of the present invention, the disk-shaped recording medium is formed as an optical disk having a single recording layer. As shown in FIG. 5, the disk-shaped recording medium 1 as an optical disk has a recording layer having basic data recorded as pits 6 therein. The basic data is recorded as digital data. When demodulated, the basic data becomes basic information such as video information as in the foregoing. When irradiated with a focused laser beam L from the optical pickup head, the pits 6 scatters the leader beam L. The optical pickup head detects a reflected light from the disk-shaped recording medium 1 to check whether the reflected light contains any signals. The height of the pits 6 is a quarter of the wavelength of the laser beam L irradiated from the optical pickup head.
[0154]In the disk-shaped recording medium 1 formed as an optical disk, a step-like portion 7 is formed in a part of each pit 6 to record add...
second embodiment
[0160 of the Disk-Shaped Recording Medium
[0161]Also, the disk-shaped recording medium 1 according to the present invention may be formed as a so-called two-layer disk including two similar recording layers 8 and 9 as shown in FIG. 6. In this case, at least the first and second recording layers 8 and 9 are stacked one on the other.
[0162]To record the additional data as the step-like portions, the step-like portion is formed in a part of each pit in the first and second recording layers 8 and 9. From such step-like portions, there is read the additional data as a reflected light of the laser beam focused in a position between the first and second recording layers 8 and 9. To focus the laser beam between the first and second recording layers 8 and 9, an astigmatism has only to be caused by the optical pickup head 25 in the playback apparatus which will further be described later to take place in the reflected light of the laser beam from the disk-shaped recording medium 1 as shown in F...
third embodiment
[0163 of the Disk-Shaped Recording Medium
[0164]Also, the disk-shaped recording medium according to the present invention may be formed as a two-layer disk including a first recording layer 18 formed on a disk substrate 17 and where basic data is recorded as pits, and a second recording layer 19 formed in a stacked relation on the first recording layer 18 and where additional data is recorded as a change in transmittance of the second recording layer 19, as shown in FIG. 8.
[0165]Basic data is recorded as pits in the first recording layer 18. From this first recording layer 18, there is read the basic data as a change in light amount of a reflected light of a laser beam irradiated from the optical pickup head.
[0166]In case the pits are formed in the first recording layer 18, the light amount of the reflected light of the laser beam irradiated from the optical pickup head is nearly zero. Such basic data is defined as “0” (or “1”) herein. In case no pits are formed in the first recordin...
PUM
| Property | Measurement | Unit |
|---|---|---|
| area | aaaaa | aaaaa |
| transmittance | aaaaa | aaaaa |
| density | aaaaa | aaaaa |
Abstract
Description
Claims
Application Information
Login to View More 


