Optical arrangement for pulse compression of a pulsed laser beam, and laser system

1 . An optical arrangement for pulse compression of a pulsed laser beam, the optical arrangement comprising:

a grating arrangement comprising a first diffraction grating and a second diffraction grating, wherein the pulsed laser beam passes the first diffraction grating and the second diffraction grating in succession,

a beam-expanding device comprising at least one beam-expanding optical element for forming a divergent pulsed laser beam that enters the grating arrangement divergently,

a deflection device for deflecting the pulsed laser beam following a first passage through the first diffraction grating and the second diffraction grating, the deflection device being configured to steer the pulsed laser beam back to the first diffraction grating and the second diffraction grating for a second passage therethrough with a beam offset that runs in a beam offset direction aligned perpendicular to a diffraction plane of the grating arrangement, and

a further deflection device arranged between the first diffraction grating and the second diffraction grating, wherein the further deflection device is an only deflection device between the first diffraction grating and the second diffraction grating, the further deflection device being configured to produce a lateral offset of the pulsed laser beam in the beam offset direction that runs perpendicular to the diffraction plane of the grating arrangement.

2 . The optical arrangement according to claim 1 , wherein the deflection device has at least two reflection surfaces for deflecting the pulsed laser beam.

3 . The optical arrangement according to claim 1 , wherein the deflection device is configured to produce the beam offset in two beam offset directions, and the deflection device has at least three reflection surfaces for deflecting the pulsed laser beam.

4 . The optical arrangement according to claim 1 , wherein the lateral offset of the pulsed laser beam in the beam offset direction produced by the at least one further deflection device is given by:

Δ

⁢

H

=

1

/

4

⁢

H

G

(

H

A

-

H

E

)

/

(

H

A

+

H

E

)

,

wherein H G is an extent of the first diffraction grating in the beam offset direction, H E is an extent of a beam cross section of the pulsed laser beam in the beam offset direction during the first passage through the first diffraction grating, and H A is an extent of the beam cross section of the deflected pulsed laser beam in the beam offset direction during the second passage through the first diffraction grating.

5 . The optical arrangement according to claim 1 , wherein the at least one further deflection device is configured to produce, in addition to the lateral offset, a second beam offset in the beam offset direction, the second beam offset corresponding to an absolute value of the beam offset produced by the deflection device in the beam offset direction.

6 . The optical arrangement according to claim 1 , wherein an extent in a direction perpendicular to a diffraction plane of a beam cross section of the laser beam emerging from the grating arrangement is greater than an extent in the direction perpendicular to the diffraction plane of the beam cross section of the laser beam entering the grating arrangement by a factor of at least 1.5.

7 . The optical arrangement according to claim 1 , wherein the beam-expanding device is configured to produce a divergence angle of the laser beam upon entrance into the grating arrangement, the divergence angle being between 0.5 mrad and 100 mrad.

8 . The optical arrangement according to claim 1 , further comprising: at least one phase correction device for at least partial compensation of a deterioration in a beam quality of the laser beam during a passage through the grating arrangement, the deterioration being able to be traced back to the divergence of the laser beam when entering into the grating arrangement.

9 . The optical arrangement according to claim 8 , wherein the phase correction device is arranged upstream of the grating arrangement in a beam path or downstream of the grating arrangement in the beam path.

10 . The optical arrangement according to claim 8 , wherein the phase correction device comprises a diffractive optical element.

11 . The optical arrangement according to claim 10 , wherein the phase correction device is integrated in the first diffraction grating or the second diffraction grating of the grating arrangement.

12 . The optical arrangement according to claim 1 , further comprising:

a collimating device for collimating the laser beam following a passage through the grating arrangement.

13 . A laser system, comprising:

a laser source for producing a pulsed laser beam, and

an optical arrangement according to claim 1 for pulse compression of the pulsed laser beam.

14 . An optical arrangement for pulse compression of a pulsed laser beam, the optical arrangement comprising:

a grating arrangement comprising a first diffraction grating and a second diffraction grating, wherein the pulsed laser beam passes the first diffraction grating and the second diffraction grating in succession,

a beam-expanding device comprising at least one beam-expanding optical element for forming a divergent pulsed laser beam that enters the grating arrangement divergently, and

a deflection device configured to steer the pulsed laser beam, after a first passage through the second diffraction grating, back to the second diffraction grating for a second passage therethrough with a beam offset that runs in a beam offset direction aligned perpendicular to a diffraction plane of the grating arrangement, and

wherein the first diffraction grating and the second diffraction grating are arranged offset from one another by a lateral offset in the beam offset direction that runs perpendicular to the diffraction plane of the grating arrangement, wherein the lateral offset between the first diffraction grating and the second diffraction grating in the beam offset direction is given by:

Δ

⁢

H

=

1

/

4

⁢

H

G

(

H

A

-

H

E

)

/

(

H

A

+

H

E

)

,

wherein H G is an extent of the first diffraction grating in the beam offset direction, H E is an extent of a beam cross section of the pulsed laser beam in the beam offset direction during the first passage through the first diffraction grating, and H A is an extent of the beam cross section of the deflected pulsed laser beam in the beam offset direction during the second passage through the first diffraction grating.

15 . An optical arrangement for pulse compression of a pulsed laser beam, the optical arrangement comprising:

a grating arrangement comprising one and only one diffraction grating, and

a beam-expanding device comprising at least one beam-expanding optical element for forming a divergent pulsed laser beam that enters the grating arrangement divergently,

a first deflection device for producing a first beam offset in a first beam offset direction, and

a second deflection device for producing a second beam offset in a second beam offset direction orthogonal to the first beam offset direction, the first deflection device and the second deflection device being arranged on opposite sides of the diffraction grating.

16 . The optical arrangement according to claim 15 , wherein the second deflection device is configured to produce a lateral offset of the pulsed laser beam in the first beam offset direction, the lateral offset being given by:

Δ

⁢

H

=

1

/

4

⁢

H

G

(

H

A

-

H

E

)

/

(

H

A

+

H

E

)

,

wherein H G is an extent of the diffraction grating in the first beam offset direction, H E is an extent of a beam cross section of the laser beam in the first beam offset direction during the first passage through the diffraction grating and H A is an extent of the beam cross section of the deflected laser beam in the first beam offset direction during the second passage through the diffraction grating.