CPC B23K 26/53 (2015.10) [B23K 26/042 (2015.10); B23K 26/046 (2013.01); B23K 26/06 (2013.01); B23K 26/064 (2015.10); B23K 26/073 (2013.01); G02B 5/001 (2013.01); G02B 27/095 (2013.01)] | 13 Claims |
1. A method for material processing of a material with a pulsed laser beam, wherein the material is at least in part transparent to the pulsed laser beam, the method comprising:
beam shaping the pulsed laser beam to form an elongated focus zone, wherein the elongated focus zone comprises at least one intensity maximum that is transverse flattened in a flattening direction;
positioning the elongated focus zone in the material;
generating, using the pulsed laser beam, a modification in the material in an asymmetric manner transverse to a propagation direction of the pulsed laser beam,
wherein the elongated focus zone is formed asymmetrically by performing a first set of operations or a second set of operations,
wherein the first set of operations comprises:
imposing, using a diffractive optical beam shaping element, a first beam shaping phase distribution that is rotationally symmetric with respect to a beam axis at least one intensity maximum extending in a ring shape around a beam axis of the pulsed laser beam,
blocking an angle range of the at least one intensity maximum with a beam aperture, and
focusing an unblocked portion of the at least one intensity maximum to form the elongated focus zone asymmetrically, and wherein the second set of operations comprises:
imposing, using the diffractive optical beam shaping element, a second beam shaping phase distribution that is non rotationally symmetric with respect to the beam axis of the pulsed laser beam onto a transverse input intensity profile of the pulsed laser beam, such that upon the pulsed laser beam propagating over a beam shaping distance (Dp) from the diffractive optical beam shaping element, the traverse input intensity profile of the pulsed laser beam is modified into a transverse output intensity profile, and such that transverse output intensity profile comprises the at least one intensity maximum extending in a ring segment structure, a ring segment of the ring segment structure being limited to an angular range around the propagation direction of the pulsed laser beam and around the beam axis of the pulsed laser beam, and
focusing the ring segment structure to form the elongated focus zone asymmetrically.
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