An embodiment of the invention relates to a sensor comprising a sensor element (10) for measuring a magnetic field, the sensor element (10) comprising a set of at least two first input ports (I1), a set of at least two exit ports (E) each of which is connected to one of the first input ports (I1) via a corresponding first beam path (B1), a set of at least two second input ports (I2) each of which is connected to a second beam path (B2), wherein the first beam paths (B1) extend through a common plane (CP) located inside the sensor element (10), said plane (CP) comprising a plurality of magneto-optically responsive defect centers, wherein the second beam paths (B2) also extend through said common plane (CP), but are angled with respect to the first beam paths (B1) such that a plurality of intersections between the first and second beam paths (B2) is defined, and wherein each intersection forms a sensor pixel (P) located at at least one of said magneto-optically responsive defect centers.