Claims
- 1. In a recording medium of air-sandwich structure comprising two disc-shaped substrates opposed to each other, the two substrates having at the center a hole of the same size to each other, with a ring-shaped inner plastic spacer, a ring-shaped outer plastic spacer and a recording layer for writing and/or reading information with a laser beam interposed between the two disc-shaped substrates, wherein the recording layer is provided on the inner surface of at least one substrate,
- the improvement including a recessed seat means for fitting and aligning said inner spacer between said two substrates, said recessed seat means comprised of a recessed portion formed around each said hole on each said substrate, wherein said inner spacer has an inside diameter larger than the diameters of the holes of the substrates.
- 2. The recording medium as claimed in claim 1, wherein said inner spacer has an inside diameter larger than the diameters of the holes of the substrates by 0.2 mm or more.
- 3. The recording medium as claimed in claim 1, wherein said inner spacer has an inside diameter larger than the diameters of the holes of the substrates by 0.5 mm or more.
- 4. The recording medium as claimed in claim 1, wherein said inner spacer has an inside diameter larger than the diameters of the holes of the substrates by 1.0 mm or more.
- 5. The recording medium as claimed in claim 1, wherein said inner spacer has an inside diameter larger than the diameters of the holes of the substrates by 20.0 mm or less.
- 6. The recording medium as claimed in claim 1, wherein said inner spacer is made of the same plastic material as that of the outer spacer.
- 7. The recording medium as claimed in claim 1, wherein said inner spacer is made of polycarbonate.
- 8. The recording medium as claimed in claim 1, wherein said inner spacer is made of an acrylic resin.
- 9. The recording medium as claimed in claim 1, wherein said inner spacer is fixed in the recessed seat means by an adhesive.
- 10. The recording medium as claimed in claim 1, wherein said outer spacer is arranged in a second recessed seat means which is comprised of recessed portions formed on each of said substrates inside of the peripheral edges of said substrates.
Priority Claims (1)
Number |
Date |
Country |
Kind |
60-221070 |
Oct 1985 |
JPX |
|
Parent Case Info
This application is a continuation of Ser. No. 914,200, filed 10/1/86, now abandoned.
US Referenced Citations (4)
Foreign Referenced Citations (1)
Number |
Date |
Country |
0129956 |
Jun 1987 |
JPX |
Continuations (1)
|
Number |
Date |
Country |
Parent |
914200 |
Oct 1986 |
|