The Rate of Optical Readout on a Compact Disk

Giovanni Cueto

Information on a compact disk is stored as a series of bumps and flat areas along a helical path. An optical reading device involving a laser light is used to read the information imprinted on a spinning disk. As the optical reading device moves radially outwards, the angular frequency of the spinning motor decreases to ensure a constant reading rate of information. Though the laser is moving normal to the spinning motion of the disk, the spinning motion of the disk suggests that the reading rate of the laser is the linear velocity of which the helical path is swiped by the laser. The maximum linear velocity of 1.65 m/s ± 31.7% , and the minimum linear velocity is 1.43 m/s ± 36.8%, with discrepancies of 15.52% and 16.00% from the range of literature values.