Abstract: Apparatus (10) for laser processing a material (11), which apparatus comprises a laser (1) and a beam delivery cable (2), wherein: the laser (1) is connected to the beam delivery cable (2); the beam delivery cable (2) is configured to transmit laser radiation (13) emitted from the laser (1), and the laser radiation (13) is defined by a beam parameter product (4); and the apparatus (10) is characterized in that: the apparatus (10) includes at least one squeezing mechanism (5) comprising a periodic surface (6) defined by a pitch (7); a length (8) of optical fibre (9) that forms part of the laser (1) and/or the beam delivery cable (2) is located adjacent to the periodic surface (6); and the squeezing mechanism (5) is configured to squeeze the periodic surface (6) and the length (8) of the optical fibre (9) together with a squeezing force (12); whereby the beam parameter product (4) is able to be varied by adjusting the squeezing force (12).

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: Apparatus for providing optical radiation (15), which apparatus comprises an optical input (13), a coupler (2), a first semiconductor amplifier (3), a controller (4), a preamplifier (61), a power amplifier (62) and an output fibre (5), wherein: the optical input (13) is for receiving input optical radiation (14); the optical input (13) is connected in series to the coupler (2), the first semiconductor amplifier (3), the preamplifier (61), the power amplifier (62), and the output fibre (5); the apparatus being characterized in that: the first semiconductor amplifier (3) comprises a waveguide (6) having a low reflecting facet (8); the first semiconductor amplifier (3) is in a double pass configuration such that the low reflecting facet (8) is connected to both the optical input (13) and the preamplifier (61) via the coupler (2); and the controller (4) is configured to cause the waveguide (6) of the first semiconductor amplifier (3) to operate in saturation thereby enabling the first semiconductor amplifier (3)

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 providing optical radiation (1), which apparatus comprises a laser diode (2), a pulse generator (9), and a modulator (5), wherein: the pulse generator (9) is configured to emit picosecond pulses; the modulator (5) is configured to emit nanosecond pulses; the laser diode (2) has a first terminal (6) and a second terminal (7); the pulse generator (9) is connected to the first terminal (6); and the modulator (5) is configured to bias the laser diode (2) below a lasing threshold (8) of the laser diode (2), and the apparatus being characterized in that: the modulator (5) is connected to the second terminal (7); the pulse generator (9) comprises a semiconductor junction (32) connected to a differentiator (4); the semiconductor junction (32) is such that electric current flowing through the semiconductor junction (32) can be turned off more quickly than it can be turned on; and the differentiator (4) is such that a step change that occurs when the electric current flowing through the semiconductor junc

Abstract: Apparatus for providing optical radiation (1), which apparatus comprises a laser diode (2), a pulse generator (9), and a modulator (5), wherein: the pulse generator (9) is configured to emit picosecond pulses; the modulator (5) is configured to emit nanosecond pulses; the laser diode (2) has a first terminal (6) and a second terminal (7); the pulse generator (9) is connected to the first terminal (6); and the modulator (5) is configured to bias the laser diode (2) below a lasing threshold (8) of the laser diode (2), and the apparatus being characterized in that: the modulator (5) is connected to the second terminal (7); the pulse generator (9) comprises a semiconductor junction (32) connected to a differentiator (4); the semiconductor junction (32) is such that electric current flowing through the semiconductor junction (32) can be turned off more quickly than it can be turned on; and the differentiator (4) is such that a step change that occurs when the electric current flowing through the semiconductor junc