Showing papers on "Digital media published in 1990"

Rewritable video disk drive

Abstract: Magneto-optical video disk drive whose recording modulation method is the FM has been developed. The SNratio over 45 dB and the horizontal resolution of 400 lines were obtained. These experimental results agree well with theoretical prediction.1. INTRODUCTION VkieoVCRs are currently used for recording moving pictures. But they / have disadvantages of low access speed. Video disks which provides / movies are known for their high quality, and high resolution pictures, Audio I and have advantages of high speed random access and a non contact diskperformance. The problem, however, is that the systems are for pre-re- 76 MHz MHz corded disk only, recording is not available. i 2 3 4 5 6 7 8 9 10 Frequency (MHz)On the other hand, magneto-optical disk memory, whose character- .istics are suitable for digital code storage, has been commercialized to . . . . . . . Figure 1 . Frequency allocation . . of direct frequency modulation . the personal computer s external storage. Under these circumstance, itis very useful to apply this re-writable magneto-optical disk to video 70recording.60There are two ways to store moving pictures. One is by digital 50recording '