Abstract: Apparatus for laser processing a material (11), comprising a laser (1), an optical fibre (2), and a coupler (125), wherein: the laser (1) is connected to the optical fibre (2); the optical fibre (2) is a multimode optical fibre having a first optical mode (21) having a first mode order (24), a second optical mode (22) having a second mode order (25), and a third optical mode (23) having a third mode order (26); the third mode order (26) is higher than the second mode order (25) which is higher than the first mode order (24); the coupler (125) switches laser radiation propagating in the first optical mode (21) to laser radiation propagating in the second optical mode (22); and the coupler (125) switches the laser radiation propagating in the second optical mode (22) to laser radiation propagating in the third optical mode (23).

Abstract: An apparatus for laser processing a material including an optical fibre, at least one squeezing mechanism, and a lens. The optical fibre is a multimode optical fibre in which laser radiation propagates in a first optical mode and in a second optical mode. The squeezing mechanism includes at least one periodic surface defined by a pitch. The periodic surface is located adjacent to the optical fibre. The pitch couples the first and second optical modes together. The first optical mode is defined by a first mode order. The second optical mode is defined by a second mode order which is higher than the first mode order. The squeezing mechanism squeezes the periodic surface and optical fibre together with a squeezing force thereby coupling the first optical mode to the second optical mode.

Abstract: Apparatus for laser processing a material (11), which apparatus comprises a laser (1), an optical fibre (2), and a coupler (125), wherein: the laser (1) is connected to the optical fibre (2); the optical fibre (2) is such that laser radiation (13) is able to propagate along the optical fibre (2) in a first optical mode (21) having a first mode order (24), a second optical mode (22) having a second mode order (25), and a third optical mode (23) having a third mode order (26); the third mode order (26) is higher than the second mode order (25); and the second mode order (25) is higher than the first mode order (24); the apparatus being characterized in that: the coupler (125) is configured to switch laser radiation propagating in the first optical mode (21) to the laser radiation propagating in the second order mode (22); and the coupler (125) is configured to switch the laser radiation propagating in the second optical mode (22) to laser radiation propagating in the third order mode (23).

Abstract: Apparatus for laser processing a material (11), which apparatus comprises an optical fibre (2), at least one squeezing mechanism (3), and a lens (4), wherein: the optical fibre (2) is a multimode optical fibre; the optical fibre (2) is such that laser radiation (13) is able to propagate along the optical fibre (2) in a first optical mode (21) and in a second optical mode (22); the squeezing mechanism (3) comprises at least one periodic surface (6) defined by a pitch (7); and the periodic surface (6) is located adjacent to the optical fibre (2); and the apparatus is characterized in that: the pitch (7) couples the first optical mode (21) and the second optical mode C(22) together; the first optical mode (21) is defined by a first mode order (24), and the second optical mode (22) is defined by a second O mode order (25) which is higher than the first mode order (24); the squeezing mechanism (3) is configured to squeeze the periodic surface (6) and the optical fibre (2) together with a squeezing force (12), ther

Abstract: Apparatus for controlling laser processing of a material (10), which apparatus comprises a laser (1) for emitting laser radiation (2); means (3) for directing the laser radiation (2) onto the material (10); at least one detector (4) for detecting optical radiation (5) that is emitted by the material (10); an electronic filter (6) for filtering an electronic signal (7) emitted by the detector (4) in response to the detector (4) detecting the optical radiation (5); and a discriminator (8) for analysing the output (9) from the electronic filter (6), the apparatus being characterised in that the electronic fitter (6) and the discriminator (8) are configured to determine at least one characteristic feature (11) of the electronic signal (7) that is indicative of the processing of the material (10) by the laser radiation (2).