Transcription: Patterns of pits and lands are laid out along a continuous spiral. As the disc turns, a precise motor keeps the laser beam in place on the path. Where the laser beam hits a pit, the light is scattered. But where it hits a land, the beam is reflected straight back along its original path. The light enters the prism again, but this time it is reflected at a 90 degree angle and strikes a device called a diode. The diode creates an electric pulse each time the light hits it. So when the laser When it hits a pit, no light bounces back. When it strikes a land, the diode sees the reflection and sends ...
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