Patent ID: 7619952

Claim:
A track calculation method for fixing track jumps of optical discs of different capacities, the method comprising: calculating a first track jump coefficient K 1 and a second track jump coefficient K 2 according to a first equation, wherein the first equation is indicated as: TotalTracks = ( K 2 + K 1 × t end ) 1 2 - ( K 2 + K 1 × t start ) 1 2 ; wherein TotalTracks indicates a total number of tracks corresponding to a capacity of an optical disc, t start indicates a starting time of playing the optical disc, and t end indicates an ending time of playing the optical disc; wherein the first track jump coefficient K 1 is indicated as: K 1 = r max 2 - r min 2 t p 2 × t l , and the second track jump coefficient K 2 is indicated as: K 2 = ( r min t p ) 2 ; wherein r max indicates a maximal radius corresponding to the capacity of the optical disc, r min indicates a minimal radius corresponding to the capacity of the optical disc; t p indicates a track pitch of the optical disc, and t 1 indicates a time difference between the starting time and the ending time of playing the optical disc; calculating an amendment ratio according to an initial location and a target location, both of which correspond to the capacity of the optical disc; updating both the first track jump coefficient K 1 and the second track jump coefficient K 2 according to the amendment ratio; determining a track displacement according to both the updated first track jump coefficient K 1 and second track jump coefficient K 2 ; and moving a pickup unit utilized for accessing the optical disc according to the determined track displacement.