lazarus@sunybcs.UUCP (Daniel G. Winkowski) (03/20/85)
From high Technology (March '85) A family of alloys recently developed by Hitachi could lead to the production of inexpensive erasable optical disc systems. The new alloys reversibly change color when heated. The colors correspond to differing crytalline structures. So, to set a certain area of the disc to bit 0, the system checks if it is already 0 (or its color representation) and if not heats it with the laser (~300 degrees C) inorder to reverse its color. The article did not mention any speeds so far obtained. There are two speeds of import, 1] the speed it takes the laser to heat the alloy to the proper temperatue, and 2] the time interval that it takes the alloy to recrystallize (cool), and assume its reverse color. -- Today we live in the future, Tomorrow we'll live for the moment, But, pray we never live in the past. -------------- Dan Winkowski @ SUNY Buffalo Computer Science (716-636-2879) UUCP: ..![bbncca,decvax,dual,rocksanne,watmath]!sunybcs!lazarus CSNET: lazarus@Buffalo.CSNET ARPA: lazarus%buffalo@CSNET-RELAY