Disc for recording information signals

Disc with prevention of static electric charge build-up

Disk hub molded from a hard synthetic resin blended with a fluor

Disk-type recording medium having a crack hindering element

Hubless optical disc having low radial runout and method of manu

Information memory medium

Information recording disk having a stepped central recess and h

Laminated optical disc and turntable for the laminated optical d

Laminated optical disc and turntable for the laminated optical d

Laminated optical disc and turntable for the laminated...

Method for centering a hub in an optical disc, and an optical st

Microphonograph record

Optical disc substrate having relatively thicker central support

Optical disk

Optical disk and disk chucking mechanism

Optical disk having clamp portion higher than substrate

Optical recording disc

Optical recording medium and disc cartridge

Optically readable information disk

Recording medium of flat surface with resin filled ring grove