| 摘要 |
1516446 Optical recording and playback PHILIPS GLOEILAMPENFABRIEKEN NV and NORTH AMERICAN PHILIPS CORP 20 Sept 1976 [23 Sept 1975] 38824/76 Heading G5R A recording or playback beam 11 passes through a transparent protective means spaced from a recording surface. As shown, the transparent protective means may be either a foil 7, Fig. 2, attached near the centre of a rotating record disc, with a centrifugal gas flow between the disc 1 and the foil 7, or a stationary strip 20, Fig. 5, extending radially over a rotating record disc 22. |
