Research Article
A Systemic Approach to the Preservation of Audio Documents: Methodology and Software Tools
Table 4
Types of optical discs [
35].
| Carrier | Period | Type of recording | Composition |
|
CD |
1981–today |
Digital | Base: polycarbonate | Reflective layer: aluminium, varnish, inks |
|
CD-recordable |
1992–today |
Digital | Base: polycarbonate | Reflective layer: gold, silver, varnish, inks |
|
CD-rewritable |
1996–today |
Digital | Base: polycarbonate | Reflective layer: varnish, inks |
|
SACD |
1999–today |
Digital | Base: polycarbonate | Reflective layer: silver | Coating: lacquer |
|
DVDA |
2000–today |
Digital | Base: polycarbonate | Inner layer: aluminium | Outer semireflective layer: gold | Coating: lacquer |
|
|