Generation of ultrafast Bessel micro-beams and applications to laser surface nanoprocessing
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Citations
Generation of nondiffracting Bessel beam using digital micromirror device
Fabrication of high-performance copper circuits using laser-induced forward transfer with large receiving gaps based on beam modulation technology
References
Bessel beams: Diffraction in a new light
Femtosecond Laser Micromachining in Transparent Materials
Machining of sub-micron holes using a femtosecond laser at 800 nm
High quality quasi-Bessel beam generated by round-tip axicon
Related Papers (5)
Frequently Asked Questions (15)
Q2. What is the role of an iris in the Fourier plane of the lens?
in the Fourier plane of the lens, an iris plays the role of a spatial filter to eliminate all orders of diffraction except +1.
Q3. What is the main purpose of the article?
Femtosecond laser ablation is a powerful tool for the structural modification of many different materials, with particular success in surface nanostructuration [12].
Q4. What are the main applications of non-diffracting beams?
Non-diffracting beams, such as Bessel beams have been mainly applied to optical manipulation of particles and atoms or nonlinear generation of harmonics [3].
Q5. What constraint does the use of Bessel beams have?
The constraint imposed by the use of Bessel beams is that the fluence needs to stay below the limit of 3 times the fluence threshold to avoid the machining by the lateral lobes.
Q6. What is the experimental setup for the producing of micro-Bessel beams?
The experimental setup for the producing of micro-Bessel beams was designed such as to give spot sizes on the sub5 µm range, allowing a flexible modification of the conical angle of the Bessel beam and maintain a long-working distance.
Q7. What is the focal distance of the first lens?
The first lens is of focal distance f=1m and is associated to an infinitely-corrected microscope objective (MO) x20 orx50 to realize a telescope of magnification M=9.1x10-3 or M=3.6x10-3 respectively.
Q8. What is the way to produce a beam on a ring?
Following Durnin's approach of Bessel beams [1], illuminating a ring aperture has been demonstrated to produce Bessel beams on µm scales [9] but the energy throughput is too low for applications to nonlinear optics and laser material processing.
Q9. What is the working distance of the microscope objective?
For applications to microstructuring, an important benefit is that the working distance is the one of the microscope objective that is 3 mm for their x20 microscope objective.
Q10. What are the properties of nondiffracting beams?
The self-healing properties of nondiffracting beams are also of prior importance for applications to propagation in turbulent media [3].
Q11. What is the definition of nondiffracting beams?
Nondiffracting beams are solutions to the Helmholtz equation that can propagate without modification of their transverse profile [1].
Q12. What is the way to measure the position of the sample?
To assess the non-critical positioning when nanomachining with Bessel beams, single-shot near threshold ablation of Corning 0211 glass was performed.
Q13. How many steps were displaced between each laser shot?
The sample surface was illuminated by individual shots of the Bessel beam and displaced by 1 µm steps on longitudinal axis between each laser shot.
Q14. What is the difference between the two processes?
both laser nanopatterning and sample imaging requires strong focusing by high numerical aperture optics, generally down to the wavelength, which leads to a nearly identical depth of focus due to diffraction laws.
Q15. What is the difference between the two types of lasers?
This demonstrates that the use of Bessel beams renders sample positioning far less critical than with usual Gaussian beams focusing, without compromising the size of the laser induced damage.