Patent ID: 7760593

Claim:
An information/reproducing apparatus, comprising: a photosensor having a plurality of divided portions, for receiving a reflected light from an information recording medium; a plurality of ΔΣ conversion circuits for convening analog output signals from the plurality of divided portions of the photosensor into one-bit digital outputs; an arithmetic circuit for arithmetically operating the one-bit output signals of the plurality of ΔΣ conversion circuits to generate an n-bit (n>1) servo error signal; a decimation filter for convening the servo error signal from the arithmetic circuit into an in-bit (m>n) servo error signal; and a normalization circuit for dividing the servo error signal generated in the arithmetic circuit by a sum signal corresponding to a sum of the photosensor outputs generated based on the outputs from the plurality of ΔΣ conversion circuits, thereby normalizing the servo error signal.