Laser Processing by Using Diffractive Optical Laser Beam Shaping Technique

Gedvilas, Mindaugas; Jäger, Erwin; Umhofer, Udo

doi:10.2961/jlmn.2011.01.0009

Cited by 63 publications

(47 citation statements)

References 1 publication

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…These diffractive elements are able to generate a Top-Hat beam profile near the Gaussian diffraction limitation [2]. FBS-1 and FBS-2 differ in their spatial modulation, which, in turn, leads to different intensity distributions of the diffracted optical field.…”

Section: Beam Shaping Opticsmentioning

confidence: 99%

“…For thin film ablation with pulsed nanosecond lasers, the advantages of a spatially-optimized laser beam profile have been demonstrated in many studies [1][2][3][4][5]. In comparison to the common Gaussian beam profile with a circular footprint of Q-switched diode pumped solid state lasers (DPSSL), the use of a Top-Hat laser beam profile with a rectangular footprint provides several benefits for laser ablation of thin films (cf.…”

Section: Introductionmentioning

confidence: 99%

“…However, contrary to the idealized representation of the laser scribed line consisting of a series of perfectly rectangular-shaped laser footprints shown in Figure 1b, the ablation spot of a single laser pulse will display deviations from the rectangular geometry, such as, e.g., rounding at the corners. For laser micromachining application, often, diffractive Top-Hat beam shaping optics are employed [1,2,6,7]. The resulting laser beam profile of such diffractive beam shapers depends strongly on, e.g., the position of the working plane, the free aperture of the beam delivery path and, certainly, on the adjustment of the beam shaper itself.…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Characterization of Laser Beam Shaping Optics Based on Their Ablation Geometry of Thin Films

2014

View full text Add to dashboard Cite

Thin film ablation with pulsed nanosecond lasers can benefit from the use of beam shaping optics to transform the Gaussian beam profile with a circular footprint into a Top-Hat beam profile with a rectangular footprint. In general, the quality of the transformed beam profile depends strongly on the beam alignment of the entire laser system. In particular, the adjustment of the beam shaping element is of upmost importance. For an appropriate alignment of the beam shaper, it is generally necessary to observe the intensity distribution near the focal position of the applied focusing optics. Systems with a low numerical aperture (NA) can commonly be qualified by means of laser beam profilers, such as a charge-coupled device (CCD) camera. However, laser systems for micromachining typically employ focus lenses with a high NA, which generate focal spot sizes of only several microns in diameter. This turns out to be a challenge for common beam profiling measurement systems and complicates the adjustment of the beam shaper strongly. In this contribution, we evaluate the quality of a Top-Hat beam profiling element and its alignment in the working area based on the ablated geometry of single pulse ablation of thin transparent conductive oxides. To determine the best achievable adjustment, we develop a quality index for rectangular laser ablation spots and investigate the influences of different alignment parameters, which can affect the intensity distribution of a Top-Hat laser beam profile.

show abstract

Section: Beam Shaping Opticsmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Characterization of Laser Beam Shaping Optics Based on Their Ablation Geometry of Thin Films

2014

View full text Add to dashboard Cite

show abstract

“…The large zone of re-molten CIGS is mainly a result of the Gaussian intensity distribution in the focal spot. As shown in [9] the shaping of the Gaussian beam into a top hat profile (in the focal plane) by a diffractive element could significantly reduce the extension of the zone of re-molten CIGS while maintaining the main characteristics of the scribe.…”

Section: P2 Scribmentioning

confidence: 98%

Selective ablation of thin films in latest generation CIGS solar cells with picosecond pulses

et al. 2012

View full text Add to dashboard Cite

Recent developments in Cu(In,Ga)Se 2 (CIGS) thin film photovoltaics enabled the manufacturers to produce highly efficient solar modules. Nevertheless, the production process still lacks a competitive process for module patterning. Today, the industry standard for the serial interconnection of cells is still based on mechanical scribing for the P2 and P3 process. A reduction of the non-productive "dead zone" between the P1 and P3 scribes is crucial for further increasing module efficiency. Compact and affordable picosecond pulsed laser sources are promising tools towards alllaser scribing of CIGS solar modules. We conducted an extensive parameter study comprising picosecond laser sources from 355 to 1064 nm wavelength and 10 to 50 ps pulse duration. Scribing results were analyzed by laser scanning microscope, scanning electron microscope and energy dispersive X-ray spectroscopy. We developed stable and reliable processes for the P1, P2 and P3 scribe. The best parameter sets were then used for the production of functional minimodules. For comparison, the same was done for a selection of nanosecond pulsed lasers. Standardized analysis of the modules has shown superior electrical performance of the interconnections and confirmed the feasibility of a dead zone width of less than 200 µm on an entire mini module.

show abstract

“…Since the invention of the laser, a vast demand on beam shaping has been verified in areas such as micro-fabrication [1], optical sensing, optical trapping [2,3] of biologic samples or even medicine. Common beam shaping setups include several optical bulk components, which are mostly large and complex [4,5].…”

Section: Introductionmentioning

confidence: 99%

Optical Fiber Tweezers Fabricated by Guided Wave Photo-Polymerization

et al. 2015

View full text Add to dashboard Cite

Abstract:In this work the use of guided wave photo-polymerization for the fabrication of novel polymeric micro tips for optical trapping is demonstrated. It is shown that the selective excitation of linear polarized modes, during the fabrication process, has a direct impact on the shape of the resulting micro structures. Tips are fabricated with modes LP02 and LP21 and their shapes and output intensity distribution are compared. The application of the micro structures as optical tweezers is demonstrated with the manipulation of yeast cells.

show abstract

Laser Processing by Using Diffractive Optical Laser Beam Shaping Technique

Cited by 63 publications

References 1 publication

Characterization of Laser Beam Shaping Optics Based on Their Ablation Geometry of Thin Films

Characterization of Laser Beam Shaping Optics Based on Their Ablation Geometry of Thin Films

Selective ablation of thin films in latest generation CIGS solar cells with picosecond pulses

Optical Fiber Tweezers Fabricated by Guided Wave Photo-Polymerization

Contact Info

Product

Resources

About