Granted Patent B2

US 12,649,200 · App. 17/628,860 · Granted Jun 9, 2026

Inventor: Tobias Dyck (Aachen, DE)

Assignee: 4JETMICROTECHGMBH

B23K26/0676B23K26/0604B23K26/0648B23K26/352B64C21/10B64C2230/26G02B27/14G03F7/70408G03F7/70475

Abstract

Claims (59)

1 . A laser processing device comprising:

an optical arrangement;

wherein the optical arrangement comprises an input for receiving a laser beam; and

wherein the input includes a beam splitter that splits the laser beam into at least two partial beams;

and wherein the optical arrangement recombines the at least two partial beams into a laser spot for generating an interference pattern in the laser spot;

wherein a first state of the laser beam at the input defines a first position P1 of a center of the laser spot and a first interference pattern;

wherein a second state of the laser beam at the input defines a second position P2 of the center of the laser spot and a second interference pattern;

wherein a change from the first state to the second state includes a change in a position of the laser beam at the input and/or a change in an angle of incidence of the laser beam with respect to the input;

wherein the change from the first state to the second state causes at least one of a distance change DP and a position change DS, wherein

(i) the distance change DP is a difference between a first distance and a second distance, wherein the first distance is between the first position P 1 of the center of the laser spot in the first state and an interference maximum closest to the first position P1 of the first interference pattern in a first direction that intersects an interference line of the first interference pattern and wherein the second distance is between the second position P2 of the center of the laser spot in the second state and an interference maximum closest to the second position P2 of the second interference pattern in the first direction, and

(ii) the position change DS is a difference between the first position P1 and the second position P2;

wherein the optical arrangement is configured to change the position change DS continuously during a change from the first state to the second state such that a condition

|DS|+|DP|= n*L

is valid, and

wherein n is a natural number;

wherein L is a distance in the first direction between two adjacent interference maxima of the first interference pattern or the second interference pattern, including a tolerance error range of ±5%.

2 . The laser processing device according to claim 1 , wherein

the at least two partial beams include two partial beams;

the two partial beams in the first state have a first optical path length difference DI_A from the beam splitter to the laser spot;

the two partial beams in the second state have a second optical path length difference DI_B from the beam splitter to the laser spot;

the optical arrangement provides, for the position change DS=P1−P2, where P1 is the first position and P2 is the second position, a difference DI_AB=DI_A−DI_B between the first optical path length difference and the second optical path length difference which causes the distance change DP so that the second interference pattern continues the first interference pattern in phase.

3 . The laser processing device according to claim 1 ,

wherein the condition is valid at least up to a position change value equal to the diameter of the laser spot.

4 . The laser processing device according to claim 1 ,

wherein the input comprises a first region and a second region;

an actuator arrangement for positioning the laser beam in the first region and subsequently in the second region.

5 . The laser processing device according to claim 1 ,

wherein the optical arrangement comprises at least one optical element operating in transmission.

6 . The laser processing device according to claim 5 , wherein a change of a path length section of a radiation path of each of the partial beams, the radiation path of which passes through the optical element, in the optical element is smaller than ±5%, wherein the change of the path length section is caused by a change in state of the laser beam at the input.

7 . The laser processing device according to claim 5 , wherein a change of a path length section of a radiation path of each of the partial beams, the radiation path of which passes through the optical element, in the optical element is smaller than ±1%, wherein the change of the path length section is caused by a change in state of the laser beam at the input.

8 . The laser processing device according to claim 5 , wherein a change of a path length section of a radiation path of each of the partial beams, the radiation path of which passes through the optical element, in the optical element is smaller than ±0.5%, wherein the change of the path length section is caused by a change in state of the laser beam at the input.

9 . The laser processing device according to claim 1 , wherein all optical elements of the optical arrangement operate exclusively in reflection.

10 . The laser processing device according to claim 1 , wherein the beam splitter is a semi-permeable mirror.

11 . The laser processing device according to claim 1 , wherein, of each transmitting optical element of the optical arrangement downstream of the beam splitter, each transirradiated surface pair located in a radiation path of at least one of the partial beams encloses an angle of at most 10 degrees.

12 . The laser processing device according to claim 1 , wherein, of each transmitting optical element of the optical arrangement downstream of the beam splitter, each transirradiated surface pair located in a radiation path of at least one of the partial beams encloses an angle of at most 5 degrees.

13 . The laser processing device according to claim 1 , wherein the optical arrangement downstream of the beam splitter does not comprise a prism.

14 . The laser processing device according to claim 1 , wherein the laser beam is a CO2 laser beam.

15 . The laser processing device according to claim 14 , wherein the CO2 laser beam has a power of at least 800 W.

16 . The laser processing device according to claim 1 , wherein the laser processing device is arranged to pattern a lacquer surface.

17 . A method of interference patterning a surface, the method comprising:

generating a first interference pattern on the surface;

generating a second interference pattern on the surface;

wherein the generating of the first interference pattern and the second interference pattern is performed by a single optical arrangement comprising an input including a beam splitter that splits the laser beam into at least two partial beams;

wherein a first position P1 of a center of a laser spot, that recombines the two partial beams, and the first interference pattern are generated by the laser beam being in a first state and a second position P2 of the center of the laser spot, that recombines the two partial beams, and the second interference pattern are generated by the laser beam being in a second state, wherein a change from the first state to the second state is performed by changing a position of the laser beam at the input and/or changing an angle of incidence of the laser beam with respect to the input, and thereby causing at least one of a distance change DP and a position change DS, wherein

(i) the distance change DP is a difference between a first distance and a second distance, wherein the first distance is between the first position P1 and the interference maximum closest to the first position P1 of the first interference pattern in a first direction that intersects an interference line of the first interference pattern and wherein the second distance is between the second position P2 and the interference maximum closest to the second position P2 of the second interference pattern in the first direction, and

(ii) the position change DS is a difference between the first position P1 and the second position P2;

wherein the position change DS is changed continuously by the optical arrangement during a change from the first state to the second state such that a condition

|DS|+|DP|= n*L

is valid, and

wherein n is a natural number;

wherein L is a distance in the first direction between two adjacent interference maxima of the first interference pattern or the second interference pattern, including a tolerance error range of ±5%.

18 . A manufacturing method of objects containing interference patterned surfaces generated by emitting a laser beam on the surface of the objects, the manufacturing method including changing a position of the laser beam at an input of an optical arrangement including a beam splitter that splits the laser beam into at least two partial beams and/or changing an angle of incidence of the laser beam with respect to the input to generate a first state defining a first position P1 of a center of a laser spot, that recombines the two partial beams, and a first interference pattern, and a second state defining a second position P2 of the center of the laser spot, that recombines the two partial beams, and a second interference pattern; wherein

(i) a distance change DP is a difference between a first distance and a second distance, wherein the first distance is between the first position P1 and an interference maximum closest to the first position P1 of the first interference pattern in a first direction that intersects an interference line of the first interference pattern and wherein the second distance is between the second position P2 and an interference maximum closest to the second position P2 of the second interference pattern in the first direction, and

(ii) a position change DS is a difference between the first position P1 and the second position P2;

wherein the position change DS is changed continuously by the optical arrangement during a change from the first state to the second state such that a condition

|DS|+|DP|= n*L

is valid, and

wherein n is a natural number;

wherein L is a distance in the first direction between two adjacent interference maxima of the first interference pattern or the second interference pattern, including a tolerance error range of ±5%.

Assignments (1)

Priority Claims (1)

Continuity (1)

References Cited (43)