: an isomer that is a stereoisomer of a compound having two or more chiral centers and that is not a mirror image of another stereoisomer of the same compound â
A compact disc is a deceptively simple looking device considering the technology required to make it. 1  CDs consist of three layers of materials: 2  A base layer made of a polycarbonate plastic. 3  A thin layer of aluminum coating over the polycarbonate plastic. 4  A clear protective acrylic coating over the aluminum layer.
There are, however, significant differences. Let's take a look at their structure. The CD is composed of one thick layer of polycarbonate with a data layer on top, followed by a metal layer that reflects the laser beam onto the sensor, followed by a metal-protecting lacquer, topped by the surface layer.