error signal is determined using signals indicating the phase difference between the signals from the sum of diagonal pairs of photodiodes a c and b d looking at the scenario illustrated in fig1 where the array 5 is midway between tracks the data patterns on adjacent tracks are uncorrelated such that the phase difference can be large when the large phase differences are presented to the phase detector and the charge pump circuitry they can cause excessive movements in the tracking error signal this results in a noisy te waveform during the times when the laser is maximally off track as shown in waveform 42 of fig4 the lower waveform 43 in fig4 shows a more acceptable waveform for a track find operation a noisy tracking error signal can degrade the performance of the tracking servo loop and can also cause problems with track counting during track find operations it will be appreciated that the sawtooth waveform which indicates that adjacent tracks are being passed over can be used for track counting in order to facilitate finding a required track on the disc the excessive noise on the te signal can be considerably reduced by using the embodiment of the invention described above to limit the.