Upward spiral

摘要

The publication of this article marks an anniversary of sorts: 20 years (and a few months) ago, Sony publicly unveiled the CD in the United States on the heels of introductions in Europe and Japan the previous fall. Philips and Sony had begun CD development in 1979; their technology harked back to ideas that Dutch physicist Klass Compaan had come up with a decade before. The Reed-Solomon EDAC scheme, a keystone of all modern optical-storage technologies, was first published even earlier, in 1960 (see "Laser-lit marvels," this issue, pg 28).