Rough repairs

Scratches on a DVD disc do far more damage than they do to a CD. Now a German
firm, CD Playright of Ludwigsburg, has worked out a surprising way to keep the
discs in a readable condition: it uses an abrasive to fix the scratches. The
company has found that a mild abrasive—contained in a cartridge—is
able to smooth the edges of scratches that would otherwise deflect the laser
scanner.