Device for homogenising a laser beam, comprising: - a first substrate having a first optically functional interface, through which the laser radiation can enter the first substrate, and having a second optically functional interface, through which the laser radiation can emerge from the first substrate, wherein at least one of the two optically functional interfaces comprises a plurality of convex cylindrical lenses (3, 3') which are arranged alongside one another in a first direction and have cylinder axes oriented parallel to one another and in this way form a first lens array, wherein adjacent cylindrical lenses (3, 3') have an identical pitch and identical focal lengths and wherein the cylindrical lenses (3, 3') are embodied such that they can split the laser radiation into a plurality of partial beams (101, 101'), - a second substrate, which is arranged in the beam path downstream of the first substrate, having a first optically functional interface, through which the partial beams can enter the second substrate, and having a second optically functional interface, through which the partial beams can emerge from the second substrate, wherein at least one of the two optically functional interfaces comprises a plurality of convex cylindrical lenses (4, 4') which are arranged alongside one another in the first direction, have cylinder axes oriented parallel to one another and in this way form a second lens array, wherein the cylindrical lenses (4, 4') can refract the partial beams (101, 101') and direct them into a working plane, and wherein adjacent cylindrical lenses (4, 4') have an identical pitch and identical focal lengths, wherein exactly one cylindrical lens (4, 4') of the second lens array is assigned to each cylindrical lens (3, 3') of the first lens array, wherein the pitches of the cylindrical lenses (3, 3') of the first lens array are greater than the pitches of the cylindrical lenses (4, 4') of the second lens array, wherein a lens vertex of a central cylindrical lens of the first lens array is aligned with a lens vertex of the central cylindrical lens of the second lens array that is assigned thereto, and the lens vertices of the other cylindrical lenses of the second lens array and the lens vertices of the cylindrical lenses of the first lens array that are assigned thereto have an outwardly increasing vertex offset proceeding from the centre of the second lens array, such that a homogeneous intensity distribution can be obtained in the working plane at least in the first direction, characterised in that for the ratio of the pitches p1/p2 of the cylindrical lenses (3, 3', 4, 4') of the first and second lens arrays it holds true that: 1 < p1/p2 ≦ 1.1, preferably 1 < p1/p2 ≦ 1.05. - a first substrate having a first optically functional interface, through which the laser radiation can enter the first substrate, and having a second optically functional interface, through which the laser radiation can emerge from the first substrate, wherein at least one of the two optically functional interfaces comprises a plurality of convex cylindrical lenses (3, 3') which are arranged alongside one another in a first direction and have cylinder axes oriented parallel to one another and in this way form a first lens array, wherein adjacent cylindrical lenses (3, 3') have an identical pitch and identical focal lengths and wherein the cylindrical lenses (3, 3') are embodied such that they can split the laser radiation into a plurality of partial beams (101, 101'), - a second substrate, which is arranged in the beam path downstream of the first substrate, having a first optically functional interface, through which the partial beams can enter the second substrate, and having a second optically functional interface, through which the partial beams can emerge from the second substrate, wherein at least one of the two optically functional interfaces comprises a plurality of convex cylindrical lenses (4, 4') which are arranged alongside one another in the first direction, have cylinder axes oriented parallel to one another and in this way form a second lens array, wherein the cylindrical lenses (4, 4') can refract the partial beams (101, 101') and direct them into a working plane, and wherein adjacent cylindrical lenses (4, 4') have an identical pitch and identical focal lengths, wherein exactly one cylindrical lens (4, 4') of the second lens array is assigned to each cylindrical lens (3, 3') of the first lens array, wherein the pitches of the cylindrical lenses (3, 3') of the first lens array are greater than the pitches of the cylindrical lenses (4, 4') of the second lens array, wherein a lens vertex of a central cylindrical lens of the first lens array is aligned with a lens vertex of the central cylindrical lens of the second lens array that is assigned thereto, and the lens vertices of the other cylindrical lenses of the second lens array and the lens vertices of the cylindrical lenses of the first lens array that are assigned thereto have an outwardly increasing vertex offset proceeding from the centre of the second lens array, such that a homogeneous intensity distribution can be obtained in the working plane at least in the first direction, characterised in that for the ratio of the pitches p1/p2 of the cylindrical lenses (3, 3', 4, 4') of the first and second lens arrays it holds true that: 1 < p1/p2 ≦ 1.1, preferably 1 < p1/p2 ≦ 1.05.