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从70年代开始发展起来的激光信息存贮技术的研究工作,对信息存贮技术有了新的突破。一种新的、有缩微胶片和磁性存贮材料优点的存贮介质——光盘应运而生。1972年荷兰飞利浦公司和美国音乐公司几乎同时展示了他们各自研制的激光视盘系统,这种系统采用的是模拟记录。1979年飞利浦公司和日本的索尼公司又首先研制出了高保真度数码录刻的声盘系统。当时的光盘主要用于录制电视节目和音乐。80年代初期,美国开始致力于模拟、数码混合录刻的光盘研究,以期解决文档的存贮。作为数据的存贮介质,则始于1986年(另一说为1985年)。在一张120毫米光盘的一个表面上,布满了相隔1.6微米的螺旋线轨迹的光道。这样的间隔,光道密度相当于16000道/英寸,比计算机软盘磁的磁道密度要大得多。沿着光道排列着一连串不同长度的凹坑,这些凹坑的宽度为0.6微米,深度为0.12微米。由于激光的波长是极为一致的,光束可以比较容易地被聚焦物镜聚焦成为直径小于1微米的小光点,正确无误地在
The research on laser information storage technology, which has been developed since the 1970s, has made new breakthroughs in information storage technology. A new storage medium with the advantages of microfilm and magnetic storage materials - optical discs came into being. In 1972, the Dutch Philips company and the American music company showcased their own laser disc systems that were produced almost simultaneously, using analog recordings. In 1979 Philips and Japan’s Sony Corporation first developed a high-fidelity digital recording sound disk system. At the time of the disc is mainly used for recording TV shows and music. In the early 1980s, the United States began to devote itself to the study of analog and digital hybrid recording discs in order to solve the problem of document storage. As a data storage medium, it began in 1986 (the other said 1985). On one surface of a 120-mm disc, it is covered with tracks of spiral traces separated by 1.6 microns. At such intervals, the track density equals 16,000 tracks / inch, which is much greater than the magnetic track density of a computer’s floppy disk. A series of pits of different lengths are arranged along the track, with a width of 0.6 microns and a depth of 0.12 microns. Since the wavelength of the laser is very consistent, the beam can be relatively easily focused by the focusing objective to a small spot of less than 1 micron in diameter,