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be configured to produce a point focus. 

[0089] Also, it should be observed that the system is optionally configured to focus the laser beam onto a tar- get area but that is not required. 

List of reference signs 

[0090] 

<img src='content_image/883071.jpg'>

## Claims 

1. Beam delivery system (2), comprising: 

2. System according to claim 1, wherein the optics as- sembly (10) is further configured to at least partly focus the at least one laser beam (8) on a second focal plane (P2) which extends at a distance from the first focal plane (P1) and which is in particular spaced away from the at least one beam passage (6),wherein the second focalplane (P2)ispreferably at an opposite side of the first focal plane (P1) from theopticsassembly(10).whereintheoptics assem- bly (10) is configured to at least partly focus the at least one laser beam (8) on a first focal plane (P1) which hasan intersection withthe atleastonebeam passage (6), 

3. System according to any of the preceding claims, including afirstinnerspace (14)and a separate sec- ond inner space (16), wherein the optics assembly is located in the first inner space (14), wherein the beam passage (6) bounds the second inner space (16). 

4. System according to any of the preceding claims, wherein: 

5. System according to any of the preceding claims, wherein: 

- a shield (4) which includes at least one beam passage (6)fortransmission ofatleastone laser beam (8); 

- an optics assembly (10) configured to at least partly focus the at least one laser beam (8) on the at least one beam passage (6); and 

-means(12)forproviding a fluid flow (F)through the at least one beam passage (6), 

wherein the system is preferably configured for per- forming laser ablation using the at least one laser beam. 

- the system (2) is configured to emit gas, e.g. a jetofgas,preferably towards a treatmentarea (A); and/or 

- during operation, a fluid flow of fluid flowing through the beampassage (6)is atleastpartial- ly, and preferably controllably, directed towards a by-product target area so that beam delivery by-products are at least partially urged towards the by-product target area by the fluid flow, wherein preferably, a direction from the beam passage to the by-product target area substan- tially corresponds to a movement direction (M) of an object to be treated with respect to the system (2), in case of such a movement. 

