1. A method for generating a series of line-shaped damage formations in a transparent workpiece along a line, comprising:
providing a laser processing device including an ultra-short pulsed laser and a focusing optic system, the laser processing device illuminating laser radiation with a wavelength that is within a transmission range of the workpiece;
providing a workpiece table and a displacement device for directing the focusing optic system onto the workpiece during generation of the damage formations and incrementally displacing the focusing optic system and the workpiece table relative to each other according to the line; and
emitting, while the focusing optic system is directed to each location of the damage formations, laser pulses in two or more successive periods, wherein the laser pulses have an energy during each period that is dimensioned so that a corresponding filament formation is produced in the workpiece, and wherein the successive periods produce consecutively aligned filament formations extending transversely through the workpiece.
2. The method as claimed in claim 1, wherein each filament formation comprises a plurality of focusing and defocusing points aligned transversely to the workpiece like a string of pearls.
3. The method as claimed in claim 1, wherein the increments of displacement of the focusing optic system relative to the workpiece are in the order of magnitude of the lateral dimension of the filament formations along the series of damage formations.
4. The method as claimed in claim 1, wherein the number of successive periods at each location of damage formation is a function of a local thickness of the workpiece.
5. The method as claimed in claim 1, wherein the focusing optic system generates a radiation beam having a cross-sectional shape with a larger dimension in a direction along the line of locations of line-shaped damage formations than transverse to the direction.
6. The method as claimed in claim 5, wherein the focusing optic system is adjustable with respect to the larger cross-sectional dimension of the radiation beam, so that alignment of the larger cross-sectional dimension is adjusted to follow the line of damage formations.
7. The method as claimed in claim 1, wherein during the generation of the series of line-shaped damage formations, the workpiece is exposed to a neutral atmosphere to prevent premature fracture along the line of locations of the damage formations.
8. The method as claimed in claim 1, further comprising exposing the damage formations to a gas that includes a content of hydroxyl (OH) ions to promote the separating and cleaving of the workpiece along the line.
9. A method for separating a workpiece by focused laser radiation, comprising:
exposing the workpiece to a first atmosphere including protective gas;
directing ultra-short pulsed laser radiation onto the workpiece, the workpiece being transparent in a range of wavelengths of the laser radiation to cause a filamentary material modification in depth in the workpiece;
moving the workpiece andor laser radiation with respect to one another to define a separation area in the workpiece;
exposing, after the laser irradiation, the workpiece to a second atmosphere including a content of hydroxyl (OH) ions that is higher than that of the protective gas atmosphere;
breaking the workpiece along the separation area defined by the material modification.
10. The method as claimed in claim 9, wherein the workpiece comprises toughened glass or glass ceramics.
11. An apparatus for separating glass or glass ceramics by focused laser radiation, comprising:
a workpiece chamber for accommodating the glass or glass ceramics;
a workpiece feeder that feed the glass or glass ceramics into the workpiece chamber;
an ultra-short pulsed laser light source that generates a filamentary material modification in depth in the glass or glass ceramics by laser irradiation;
a displacing device that moves the workpiece andor the laser light source relative to each another;
wet steam feed device that feeds a gas stream into the workpiece chamber; and
a separating device that separates the workpiece along a separation line defined by the material modification.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. A method for examining at least one object, during which properties of the object are detected within a spatial frequency space formed by spatial frequencies in various measurements,
characterized in that
after a first HF excitation, first and second measurements are made in first areas of the spatial frequency space, whereby the measurements each acquire the object in a central area of the spatial frequency space at a high acquisition rate and in peripheral areas of the spatial frequency space at a lower acquisition rate than in the respective central area of the spatial frequency space, whereby the first measurement is made within a time interval after the HF excitation, said interval being selected in such a way that the first measurement is essentially T1-weighted, that the second measurement is made within a later time interval, whereby the later time interval is selected in such a way that the second measurement is essentially T2*-weighted, that subsequently an additional HF excitation is performed, that after the additional HF excitation, at least two additional measurements are made in second areas that are different from the first areas, whereby the second areas likewise encompass the central area of the spatial frequency space having a high acquisition rate and peripheral components of the spatial frequency space having a lower acquisition rate than the central area, whereby the first measurement made after the additional excitation is made within a time interval after the additional HF excitation, which is selected in such a way that the first measurement is essentially T1-weighted, that an additional measurement after the additional HF excitation is made within a later time interval, whereby the additional time interval is selected in such a way that the additional measurement is essentially weighted with T2* and that subsequently, the measurements weighted with T1 are combined to form one image and the measurements weighted with T2* are combined to form and additional image.
2. The method according to claim 1, characterized in that measurements of the first and second areas are made with at least three different acquisition frequencies.
3. The method according to claim 1, characterized in that the object is examined using a sampling sequence EPIC<nov, k, s, i>=nov, nov \u2212, 1, nov \u22122, . . . 0, 1, 2, \u2212N2k+2, \u2212N2k+1, \u2212N2+2s\u2212i, \u2212N2+s\u2212i, whereby nov stands for the quotient of the number of lines acquired in the keyhole and of the total number of scanned lines, k stands for a keyhole factor, s stands for a SPARSE factor and i is a running variable index, and N stands for the number of times the keyhole is acquired.
4. The method according to claim 3, characterized in that the acquisition is carried out in acquisition modules with acquisition times TA for which the following applies:
TA
=
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\u2062
\u2062
t
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N
\u2061
(
n
ov
\u2062
s
+
k
–
1
2
\xb7
s
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k
)
.
5. The method according to claim 1, characterized in that the first and second areas of the spatial frequency space extend parallel to each other, at least in certain sections.
6. The method according to claim 1, characterized in that, with at least one measurement, the acquired areas form a disjunctive set.
7. The method according to claim 6, characterized in that disjunctive elements of the individual sets extend parallel to each other in the spatial frequency space, at least in certain sections.
8. The method according to claim 1, characterized in that the measurements are carried out in such a way that a cycle is formed in which at least some of the areas of the spatial frequency space that differ from each other are once again acquired in additional measurements.