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How Does a CD Player Work?
Today there are many different types of CD players that are available. The main problem for the consumer is in choosing that player that will offer him everything that he requires. This can be quite a difficult task to accomplish due to the quality, style, design as well as the technical specifications of different players. There are many CD players that are quite cheap, whereas others are expensive. Bu the one thing that has to be taken into consideration is that rate at which the drive motor spins. The drive motor in a CD player is the part that has the potential of spinning a disc at the right pace. Depending on the portion of the disc that is currently being played, the motor should have the ability of gradually adjusting the speed. Certain portions of the song would require a mere 200 rpm, while other sections would need a much faster rpm of at least 500. The tracking mechanism adjusts the laser so that it can focus on the correct part of the spinning disk.
The section of the disc that is being viewed by the laser will then get stored in elongated bumps on the CD surface. Each of the bumps is no longer than 0.5 microns with the length at 0.83 microns while the height stays at no more than 125 nanometers. These are neatly organized in the form of a spiral which is approximately 5km long.
Different layers form the CD. Two of these layers are the polycarbonate layer and the aluminum layer. First the laser of the CD player will read the data from the polycarbonate layer and then the data from the aluminum layer. The various bumps on the CD will then be used as a determination of which parts of the disc have to be read.