Method for establishing the distance of a light beam from a point on a body surface by means of a light sensor with a plane measurement field, comprising the following steps: positioning the measurement field in such a way that the light beam strikes the measurement field, pivoting the measurement field about a first pivot axis that extends parallel to the light beam and that is spaced apart from the latter and pivoting the measurement field about at least one second pivot axis while the measurement field is pivoted about the first pivot axis, wherein the second pivot axis extends skew in relation to the light beam, wherein the measurement field is pivoted during the pivoting about a common point of intersection of the second pivot axis and the first pivot axis, said common point of intersection having a predefined relative position in relation to the point on the body surface, and wherein a pivot position in which the light beam is oriented at right angles to the measurement field is passed through at least three times when pivoting about the second pivot axis, capturing the positions of the light spot of the light beam on the measurement field by the light sensor, the positions being adopted by the light spot on the measurement field during the pivoting according to step B, establishing those positions of the positions captured in step C which describe a circular arc with a distance from the point of intersection on the measurement field, said distance being smaller than the distance of the remaining positions, captured in step, in relation to the point of intersection, and determining the distance of the light beam from the point on the body surface on the basis of the extent of the circular arc according to step D and the predefined relative position in relation to the point on the body surface. positioning the measurement field in such a way that the light beam strikes the measurement field, pivoting the measurement field about a first pivot axis that extends parallel to the light beam and that is spaced apart from the latter and pivoting the measurement field about at least one second pivot axis while the measurement field is pivoted about the first pivot axis, wherein the second pivot axis extends skew in relation to the light beam, wherein the measurement field is pivoted during the pivoting about a common point of intersection of the second pivot axis and the first pivot axis, said common point of intersection having a predefined relative position in relation to the point on the body surface, and wherein a pivot position in which the light beam is oriented at right angles to the measurement field is passed through at least three times when pivoting about the second pivot axis, capturing the positions of the light spot of the light beam on the measurement field by the light sensor, the positions being adopted by the light spot on the measurement field during the pivoting according to step B, establishing those positions of the positions captured in step C which describe a circular arc with a distance from the point of intersection on the measurement field, said distance being smaller than the distance of the remaining positions, captured in step, in relation to the point of intersection, and determining the distance of the light beam from the point on the body surface on the basis of the extent of the circular arc according to step D and the predefined relative position in relation to the point on the body surface.