- CD players use a laser lens to read bumps engraved along the reflective grooves of a CDs. The groove starts from the outside of the CD and spirals to the inside. Data is processed when the beam spots a bump along the groove. The laser beam is refracted and spliced into two beams. One beam is reflected to a sensor in the CD player and the other to a mobile mirror.
- The mobile mirror works as a "pick-up" as it moves back and forth along a monorail-like track beneath the spinning CD. A motor spins the CD at a constant angular velocity (CAV)--meaning the CD is spun at a constant speed. The processing unit of the CD player adjusts density of the data processed to contend with the varying amounts of data located at each point of the CD --a revolution around the outer portion would contain more data than a smaller revolution near the center of the CD.
- Information received from the CD is sent to the digital audio converter to be processed and converted into electrical pulses, and the pulses are sent to the audio jack. When a pair of headphones or a set of speakers is inserted into the the jack, the pulses travel to the speakers and are converted into vibrations, which we hear as sound.
