A magnetic recording apparatus which, even when crosstalk occurs between signals
from three photosensitive parts of a photodetector, can detect a high-precision
tracking error signal with stability. In a signal processing unit which processes
electrical signals outputted from a photosensitive part of a photodetector to detect
a tracking error signal, an output signal from and I-V converting unit is subjected
to voltage division by voltage-dividing units, and voltage-divided output signals
and output signals from I-V converting units are subjected to differential calculation
by differential arithmetic units, respectively.
