- Joined Dec 31, 1969
In Chapter 5 of Volume 4, under "Memory with moving parts" it is stated that with CD's "Binary bits are 'burned' into the aluminum as pits by a high-power laser". This is factually incorrect because commercial CD's (the ones with pits) are pressed in a stamp. There is no laser or burning involved in the creation of the finished CD. The only CD that is "burned" are CD-Rs. CD-R's don't have pits. With CD-R's, a laser burns into a dye causing it to either let light pass through the dye (to the reflective aluminum) or not let light pass through the dye.