Optical Devices

Optical Devices

1. They are CD's & DVD's

   • Similar to hard drives
     • The surface is divided into sectors and a single (sectors) tracks
   • Track is a spiral
   • Data is stored on the sectors and on the tracks.
     • Small indentations are made in the disk

2. Reading the data/writing the data

   • A laser is aimed at the surafce and where there is no indentation the laser light is focoused in such away that it disperses
   • Where there is no indentation the laser light has to travel a greater distance
     • Far enough for the light to become focoused