capacity was determined for each optical disc using the AFM and OM bit lengths.
The track lengths calculated from Equation 1, 2 and 3 for CD, DVD and BD are
divided by the corresponding bit length to determine the maximum data storage
capacity for each optical disc. However, this data storage does not account for
the error correction codes or modulation efficiency, so usable data storage
must be calculated to compare to the actual capacity. Table 2 shows the usable
storage capacity calculated after applying error correction codes and
modulation efficiency. Track length, bit length, maximum storage capacity and
the actual capacity are also listed in Table 2 on the next page. The errors in
the calculated values are determined from hand taken measurements of the pitch
length, inner radius, and outer radius as well as the precision error.