System for analysing a collimated light beam guided by a beam guiding optical unit, comprising • a first Fourier optical unit which is formed by a first focusing lens element having a first focal length (f 1 ); • a graduated neutral density filter arrangement which in relation to the beam path is arranged downstream of the first focusing lens element at the distance of the first focal length (f 1 ); • a second Fourier optical unit which is formed by a second focusing lens element having a second focal length (f 2 ) and which in relation to the beam path is arranged downstream of the graduated neutral density filter arrangement at the distance of the second focal length (f 2 ); and • a light intensity sensor arrangement which in relation to the beam path is arranged downstream of the second focusing lens element at the distance of the second focal length (f 2 ), the light intensity sensor arrangement having at least one light intensity sensor ; • wherein the light intensity sensor arrangement is designed such that it measures, for each graduated neutral density filter of the graduated neutral density filter arrangement , in each case the light intensity transmitted by said graduated neutral density filter; and • wherein the graduated neutral density filter arrangement has a first graduated neutral density filter with a linear transmission profile in a first spatial direction and a second graduated neutral density filter with a linear transmission profile in a second spatial direction, which differs from the first spatial direction, and/or wherein the graduated neutral density filter arrangement has at least one graduated neutral density filter with a transmission profile that is parabolic at least in a predetermined spatial direction. • a first Fourier optical unit which is formed by a first focusing lens element having a first focal length (f 1 ); • a graduated neutral density filter arrangement which in relation to the beam path is arranged downstream of the first focusing lens element at the distance of the first focal length (f 1 ); • a second Fourier optical unit which is formed by a second focusing lens element having a second focal length (f 2 ) and which in relation to the beam path is arranged downstream of the graduated neutral density filter arrangement at the distance of the second focal length (f 2 ); and • a light intensity sensor arrangement which in relation to the beam path is arranged downstream of the second focusing lens element at the distance of the second focal length (f 2 ), the light intensity sensor arrangement having at least one light intensity sensor ; • wherein the light intensity sensor arrangement is designed such that it measures, for each graduated neutral density filter of the graduated neutral density filter arrangement , in each case the light intensity transmitted by said graduated neutral density filter; and • wherein the graduated neutral density filter arrangement has a first graduated neutral density filter with a linear transmission profile in a first spatial direction and a second graduated neutral density filter with a linear transmission profile in a second spatial direction, which differs from the first spatial direction, and/or wherein the graduated neutral density filter arrangement has at least one graduated neutral density filter with a transmission profile that is parabolic at least in a predetermined spatial direction. <EOS>