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Collimating lenses are an important component of laser ranging systems, and high overload environments severely affect the beam shaping effect of such lenses. This study proposes a buffer isolation method on the basis of impact stress wave attenuation theory for collimating lens spacers. ANSYS finite element software was applied to simulate the high load dynamics of collimating lenses, and the buffer isolation performance of different materials and composite structures was compared and analysed. Optical simulation analysis of the collimating lenses under different buffer conditions was performed using ZEMAX software to study the mechanism by which a high overload affects the collimating lenses. High overload and optical shaping experiments based on theoretical analysis were further conducted. Results showed the superiority of butadiene rubber to polytetrafluoroethylene after application of 70000 g impact acceleration. The combination-gasket method was superior to the single-gasket method, and the sandwich combination-gasket method was superior to the double-layer combination-gasket method.

A watt-level directly diode-pumped continuous-wave (CW) Ti:Sapphire oscillator was demonstrated for the first breakthrough by a high-power green laser-diode-pumped module employing the technologies of beam shaping, beam collimation, polarization beam combining, and fiber coupling. A 1.36-W output power and 10.6% of slope efficiency were obtained based on the double-concave (DC) cavity configuration. This is the highest CW output power from Ti:Sapphire (Ti:S) oscillator directly pumped by green laser diodes (LDs) reported so far.

Efficient beam supercollimation is proposed and shown experimentally by axisymmetric aperiodic photonic structures. The structure consists of equidistant layers of concentric refraction index rings, with the transverse period of the rings varying from layer to layer along the structure. Numerically designed and optimized axisymmetric photonic structures are inscribed in silica glass by femtosecond pulses. Strong enhancement (more than by one order of magnitude) of the axial beam component is demonstrated, resulting in the record performance of the beam supercollimation.

High thermal gradients and complex melt pool instabilities involved in powder bed fusion–based metal additive manufacturing using focused Gaussian-shaped beams often lead to high porosity, poor morphological quality, and degraded mechanical performance. We show here that Bessel beams offer unprecedented control over the spatiotemporal evolution of the melt pool in stainless steel (SS 316L) in comparison to Gaussian beams. Notably, the nondiffractive nature of Bessel beams enables greater tolerance for focal plane positioning during 3D printing. We also demonstrate that Bessel beams significantly reduce the propensity for keyhole formation across a broad scan parameter space. High-speed imaging of the melt pool evolution and solidification dynamics reveals a unique mechanism where Bessel beams stabilize the melt pool turbulence and increase the time for melt pool solidification, owing to reduced thermal gradients. Consequently, we observe a distinctively improved combination of high density, reduced surface roughness, and robust tensile properties in 3D-printed test structures.

In this study, we present the simulations and experimental observations of photonic jet (PJ) shaping by control of tangential electric field components at illuminating wavelengths of 405 nm, 532 nm, and 671 nm. The PJs are generated by a single dielectric 4-micrometer cube that was fabricated from polydimethylsiloxane (PDMS). The dielectric cube is deposited on a silicon substrate and placed on two aluminum masks with a width equal to the side length of the cube. Due to the appearance of the metal masks, the focal length and decay length of the generated PJs decreased almost twice, while the PJ resolution increased 1.2 times. Thus, PJ shaping can be controlled by the presence of the metal mask along the lateral surface of the cube without changing the external shape or internal structure of the cube. This effect is based on the control of the tangential components of the electric field along the lateral surface of the cube. In the case of a one-sided metal mask, the effect of optical deflection and bending is predicted to form a photonic hook. Due to the low cost of these dielectric cubes, they have potential in far-field systems to better meet the requirements of modern optical integration circuits and switches.

OLEDs are thin-film devices consisting of multilayers of organic thin films sandwiched between a metal and an ITO electrodes. Because of the different refractive indices of the layers in the thin film stack, different optical modes are trapped in the device. In this talk, we will first discuss the physics of these optical modes and describe techniques to characterize them. We will then describe how to use various photonic structures to maximize the light output and manipulate these optical modes to control the polarization as well as directionality to achieve beam shaping.

Recent developments in laser beam sources expand the possibilities of laser beam welding of similar and dissimilar copper joints. New methods of beam shaping and adjustable intensity profiles using two layer fibers create a center and ring spot, which is the newest state of the art in fiber laser beam sources. In this study, the influences and possibilities of adjustable intensity profiles on the weldability of steel copper dissimilar lap joints with copper on the top side will be discussed. The results show that the former problems of spattering and poor beam coupling in copper can be avoided through new beam shaping technologies and adjusted parameter settings. In the investigations joints without melt ejections on copper surfaces of state of the art fiber laser technologies are demonstrated and the influence of different intensity distributions on the weld geometry will be discussed.

Significance Fast submicrometer-scale 3D printing techniques are of interest for various applications ranging from photonics and electronics to tissue engineering. Interference lithography is a versatile 3D printing method with the ability to generate complicated nanoscale structures. Its application, however, has been hindered by either the complicated setups in multibeam lithography that cause sensitivity and impede scalability or the limited level of control over the fabricated structure achievable with mask-assisted processes. Here, we show that metasurface masks can generate complex volumetric intensity distributions with submicrometer scales for fast and scalable 3D printing. These results push the limits of optical devices in controlling the light intensity distribution and significantly increase the realm of possibilities for 3D printing., Fast, large-scale, and robust 3-dimensional (3D) fabrication techniques for patterning a variety of structures with submicrometer resolution are important in many areas of science and technology such as photonics, electronics, and mechanics with a wide range of applications from tissue engineering to nanoarchitected materials. From several promising 3D manufacturing techniques for realizing different classes of structures suitable for various applications, interference lithography with diffractive masks stands out for its potential to fabricate complex structures at fast speeds. However, the interference lithography masks demonstrated generally suffer from limitations in terms of the patterns that can be generated. To overcome some of these limitations, here we propose the metasurface-mask–assisted 3D nanofabrication which provides great freedom in patterning various periodic structures. To showcase the versatility of this platform, we design metasurface masks that generate exotic periodic lattices like gyroid, rotated cubic, and diamond structures. As a proof of concept, we experimentally demonstrate a diffractive element that can generate the diamond lattice.

Fluorescence microscopy has long been a valuable tool for biological and medical imaging. Control of optical parameters such as the amplitude, phase, polarization, and propagation angle of light gives fluorescence imaging great capabilities ranging from super-resolution imaging to long-term real-time observation of living organisms. In this review, we discuss current fluorescence imaging techniques in terms of the use of tailored or structured light for the sample illumination and fluorescence detection, providing a clear overview of their working principles and capabilities.

We report a novel beam homogenizer for digital micromirror device lithography system. Such a beam homogenizer contains only one random freeform microlens array (rfMLA). And the rfMLA consists of different freeform microlenses. By the individual design and irregular arrangement of the microlenses, efficient and uniform beam shaping results have been obtained, and the interference patterns in particular are greatly weakened. Compared with traditional beam homogenizer, the energy efficiency has been increased from 62.00% to 69.70%, and the uniformity for incoherent light and coherent light have been improved from 91.93% to 97.60% and from 79.00% to 94.33%, respectively. rfMLA has great potential for enhancing the performance of DMD lithography system and other optical systems, particularly for the homogenization of the beam and the integration of the system.

The Cu(In,Ga)Se2 (CIGS) thin film solar cell is a promising material architecture considering its high photovoltaic (PV) efficiency at low material cost. Recently, the authors demonstrated all lase...

A Double Layer Beam Shaping Assembly (DLBSA) was designed to produce epithermal neutrons for BNCT purposes. The Monte Carlo N-Particle eXtended program was used as the software to design the DLBSA and phantom. Distribution of epithermal neutron and gamma flux in the DLBSA and phantom and absorbed dose in the phantom were computed using the Particle and Heavy Ion Transport code System program. Testing results of epithermal neutron beam irradiation of the water phantom showed that epithermal neutrons were thermalized and penetrated the phantom up to a depth of 12 cm. The maximum value of the absorbed dose was 2 × 10-3 Gy at a depth of 2 cm in the phantom.

A tractor beam, which has the ability to attract objects, is a class of special optical beams. Currently, people are using the holographic technology to shape complex optical tractor beams for both fundamental research and practical applications. However, most of the work reported is focusing on generating two-dimensional (2D) tractor beams and simple three-dimensional (3D) tractor beams, which has limitations in the further development on mechanism and application of beam shaping. In the present work, we are introducing our study in designing multiple 3D tractor beams with spatial location regulated independently. Meanwhile, each individual beam could be prescribed along arbitrary geometric curve and twisted at arbitrary angles as desired. In our method, the computer-generated hologram (CGH) of each curve is calculated, and all the CGHs are multiplexed and encoded into one phase-only hologram by adding respective linear phase grating such that different 3D curves appeared in the different positions of the focal regions. We experimentally prove that the generation of optical tractor beams at 3D configuration can be readily achieved. The generated beams in the present study are especially useful for applications such as multiple micro-machining optical trapping and complex 3D manipulation.

Design and optimization of double layer Beam Shaping Assembly (DLBSA) has been conducted using the MCNPX code. The BSA is configured to comply with such a construction having typically a double moderator, a reflector, a collimator, and a filter. The optimization of various combinations of materials that compose the moderator, reflector, and filter yields such quality and intensity of radiation beams that conform to the requirements for Boron Neutron Capture Therapy. The composing materials are aluminum and BiF3 for moderator, lead and graphite for the reflector, nickel and polyethylene borate for the collimator, and iron and cadmium for the filter. Typical beam parameters measured at the exit of the collimator are epithermal neutron flux of 1.1 ⋅ 109 n/cm2 ⋅ s, the ratio of epithermal neutron flux to thermal neutron and fast neutron flux 344 and 85, respectively, and the values of fast neutron and gamma dose to epithermal neutron flux 1.09 ⋅ 10-13 Gy ⋅ cm2 and 1.82 ⋅ 10-13 Gy ⋅ cm2, respectively. Analysis of epithermal neutron flux and neutron beam spectrum using the PHITS code reveals that the distribution of epithermal neutron spreads out in the DLBSA. The highest intensity is found in the moderator and decline down-stream of the collimator and filter. The spectrum of neutron beams displays a narrow spike with that peaks at 10 keV.

Femtosecond laser modification of transparent materials offers selective chemical etching, facilitating three-dimensional (3D) micro-structures to open into flexible shapes as configured by multi-line scanning [1] . While surface aberration and other beam shaping methods have been widely studied in processing of transparent glasses [2] , [3] , the influence of such beam shaping on chemical etching has not been addressed. This paper examines the microstructure resulting in fused silica from beams with concave and convex conical phase front [4] . The conical beam shaping is shown to improve etching rates and surface morphology, compensate for deep focussing aberration and provide an attractive tailoring of the microchannel cross-sectional profile.

Planar diverging lenses attached to the front end of a dielectric rod antenna are proposed to control the heating area on the human body to assist the electroporation treatment of different tumor sizes. The desired 5–7 °C temperature elevation of the tumors is achieved in 3 minutes by applying 2.1-3.6 W input power depending on the size of tumor. In order to treat the tumors located 3–7 mm below the skin surface, the applicator is operated at 8 GHz. The experimental results obtained by measuring a pork muscle tissue show good agreement with electro-thermal simulations.

By adapting azobenzene polymer layer, both linear and concentric surface relief gratings (SRGs) have been successfully inscribed over optical fiber endfaces based on developing

We report on the separation of complex inner and outer contours from glass articles with curved surfaces using ultrashort pulsed lasers. To achieve single-pass, full-thickness modifications along the entire substrate a processing optics is presented that allows for beam shaping of non-diffracting beams and, additionally, for aberration compensation of phase distortions occurring at the curved interface. The glass articles finally separated by thermal stress or via selective laser etching meet the demands of the medical industry in terms of micro-debris, surface quality and processing speed.

Metasurfaces supply a planar approach for flexible wavefront manipulation, thus facilitating the integration and minimization of optical elements, especially in the terahertz (THz) range. High efficient THz metadevices are highly pursued at present. Here, we propose a bilayer design to improve the efficiency of metadevice. Two silicon pillar arrays with distinguishing geometries are integrated on single silicon substrate. On one side, elliptical silicon pillars, with geometry optimized for the target frequency, are spatially orientated to realize the desired Pancharatnam-Berry phase. On the other side, uniform circular silicon pillars are set to suppress the reflection. With this design, versatile metadevices such as lens, lens array, polarization fork grating, Bessel vortex generator, and Airy beam generator are demonstrated. Maximum efficiency up to 95% for the target frequency and excellent design flexibility are verified. It provides a practical strategy for the generation of compact and high-efficiency THz metadevices, which suit for high-performance THz imaging and communication apparatuses.

We experimentally demonstrate phase encoding in SHG with transparent all-dielectric metasurfaces. While a similar task was previously achieved with plasmonic metasurfaces for THG beam shaping, here we obtain three-order-of-magnitude higher generation efficiency without thermal dissipation.

We report a new optofluidic transmissive wavefront modulator optimized for gravity-neutral performance and miniaturized dimensions. The modulator is optimized for compensating gravity-induced aberrations by simulating its behavior with various design configurations. Miniaturization was achieved by a novel method for liquid filling and sealing of the modulator. Key elements of the new interface are intra-substrate channels fabricated by a selective laser-induced etching process. The modulator has a final thickness of 750 µm and can be operated in any orientation without significant loss of modulation quality.

Several beam shaping strategies have been proposed as an effective approach to fully exploit the average power delivered by the last generation of high power, industrial, femtosecond laser whilst avoiding unwanted thermal effects. Nevertheless, in the case of surface texturing, the effect of the profile modifications on the surface morphology has been barely investigated. The objective of our study is to understand more deeply how the beam profile features will impact the surface evolution. By tailoring the beam profile, we want to understand if it is possible to increase the process throughput. A comprehensive study has been carried out with a 35 W, 2MHz, femtosecond industrial laser. The impact of the beam intensity profile on texturing of metallic surface has been investigated. We systematically studied how the beam size (from 10 μm to few hundreds of microns) impacts the generation and evolution of Laser Induced Periodic Surface Structures (LIPSS) on Stainless Steel surface. SEM analysis has been carried out for all the generated morphologies.

To moderate fast neutrons produced by accelerator to appropriate therapeutic energies for boron neutron capture therapy (BNCT), beam shaping assembly (BSA) is required definitely. In this work, based on a model of 2.5 MeV/30 mA proton accelerator, the Monte Carlo simulation software MCNPX was employed to design multi-terminal BSAs. All parameters for both the thermal and epithermal neutron beams at the exit ports of the designed BSAs meet the treatment recommendation values proposed by the International Atomic Energy Agency (IAEA). The clinical parameters of the thermal and epithermal neutron beams were also calculated for clinical indication consideration.

We present laser-polished freeform optics used for highly efficient single- and multimode beam shaping. The design freedom provided by truly freeform fabrication allows us to address a wide range of laser applications with control over intensity distribution and uniformity.

A computational fluid dynamics approach is used to analyse the influence of beam shaping in fusion welding on melt thermal flow. Three beam shapes are studied at several welding travel speeds: a reference Gaussian profile and its elliptic elongations along and transverse to the welding travel direction. It is found that these beam shapes change not only the intensity and direction of the melt thermocapillary flow but also the flow pattern. For instance, and contrary to the other profiles, the beam shape elongated along the welding travel direction generates melt front vortices that assist metal pre-heating. It can result in deeper penetration, larger melt volume, and lower amount of thermal energy diffused into the heat affected zone. The simple elongation of a beam profile has thus a non-linear effect on the melt flow and in turn on the seam geometry as well as the temperature gradients in the heat affected zone.

The optical fiber microtips can be utilized as a unique platform for various applications, including optical coupling, sensing, beam shaping and optomechanical systems. Here, we fabricate a polymer microtip between two SMFs and the whole device is integrated in a V-groove which is portable and reusable. Characteristics of the microtip bridge will be discussed. This integrated portable device can be used in various coupling and sensing applications.

The temperature-dependent optical properties of PECVD deposited amorphous silicon films are determined for radiation wavelengths of 1000 nm up to 2000 nm in a temperature range of up to 1110 K. The measurements are performed at heating rates of over 2300 K/s in order to shift the onset of solid-phase crystallization of the amorphous material to temperatures above 1110 K and to make the optical properties of amorphous silicon accessible for examination. In this work, the laser-based measurement setup, the experimental procedure, the simulation methods, and the resulting material-specific data are shown.

Boron Neutron Capture Therapy (BNCT) is facing a new era where diferent projects based on accelerators instead of reactors are under development. The new facilities can be placed at hospitals and will increase the number of clinical trials. The therapeutic efect of BNCT can be improved if a optimized epithermal neutron spectrum is obtained, for which the beam shape assembly is a key ingredient. In this paper we propose an optimal beam shaping assembly suited for an afordable low energy accelerator. The beam obtained with the device proposed accomplishes all the IAEA recommendations for proton energies between 2.0 and 2.1 MeV. In addition, there is an overall improvement of the fgures of merit with respect to BNCT facilities and previous proposals of new accelerator-based facilities., Junta de Andalucía (Andalusian Regional Government, Programa Operativo FEDER Andalucia 2014–2020 under contract A-FQM-371-UGR18), University Chair “Neutrons for Medicine”: Spanish Fundación ACS, Capitán Antonio, La Kuadrilla de Iznalloz and Sonriendo se Puede Ganar, Spanish Ministry of Science, Innovation and Universities - FPU grant FPU17/02305

We present laser cooling of atomic Rb using a metasurface optic for beam shaping and polarization control. This technology will enable miniaturized quantum devices and calibration-free sensors utilizing the properties of cold atoms.

A volume holographic optical element is designed and fabricated using photopolymer (PQ- PMMA) for multifocal super Gaussian (SG) beam spots and can be used for illuminating sample in confocal microscopy to reduce the scanning time.

In this paper, we demonstrated a superconductive sensing-based system for cerebral blood flow monitoring via diffuse correlation spectroscopy at 1064nm. Findings show high brain sensitivity and fast monitoring using the presented system.

The miniaturization of optical systems enables new applications. The potential of SLE to produce mechanical mounts for miniaturized optical systems will be demonstrated by an optical measuring probe for the determination of drop size distribution.

Freeform optics reveals many benefits for beam-shaping systems. We propose an approach by reproducible ray mapping functions and surface optimizations to significantly reduce the design complexity of freeform beam shaping optics.

The industrial maturity of ultrashort pulsed lasers has triggered the development of a plethora of material processing strategies. Recently, the combination of these remarkable temporal pulse properties with advanced structured light concepts has led to breakthroughs in the development of novel laser application methods, which will now gradually reach industrial environments. We review the efficient generation of customized focus distributions from the near infrared down to the deep ultraviolet, e.g., based on non-diffracting beams and 3D-beam splitters, and demonstrate their impact for micro- and nanomachining of a wide range of materials. In the beam shaping concepts presented, special attention was paid to suitability for both high energies and high powers., Accepted manuscript, 19 pages, 20 figures and 111 references

Various beam shaping approaches were examined to counter the negative influence of surface aberration arising when inscribing optical waveguides deeply inside of glass with a femtosecond laser. Aberration correction was found unable to completely recover the low-loss waveguide properties, prompting a comprehensive examination of waveguides formed with focused Gaussian–Bessel beams. Diverging conical phase fronts are presented as a hybrid means of partial aberration correction to improve insertion loss and a new, to the best of our knowledge, means of asymmetric beam shaping. In this way, low-loss waveguides are presented over shallow to deep writing depth (2.8 mm) where morphological and modal properties could be further tuned with conical phase front.

According to the requirement of system，an one-dimensional beam shaping system is designed for semiconductor laser. In this beam shaping system, we choose an aspheric cylindrical mirror as the shaping element. To design the aspheric cylindrical mirror, we first calculate the incipient structure and then use the software light tools to optimize and simulate. The result shows that for a semiconductor laser whose beam diverging angle is 40°, the diverging angle will smaller than 1mrad after shaping by the aspheric cylindrical mirror. Also, we test the actual beam shaping system and the result shows that it meets the requirement of system well.

Rapid development of terahertz technologies causes constant search for new possibilities of making optical elements, needed for proper beam shaping. Large optical elements are often used in THz setups to collect as much power as possible. Unfortunately, traditional refractive optical lenses significantly absorb already weak signal. This is the reason for searching for new solutions in the form of diffractive optical elements (DOEs). For higher terahertz frequencies however, it is challenging to find an appropriate material as well as uncomplicated manufacturing methods. In this article, we present a higher-order kinoform (HOK) made of paraffin, cast from 3D-printed mold, efficiently working for 0.6 THz.

Emerging applications requiring light beam manipulation, such as high-efficiency sunlight concentrators for solar cells, switchable micro-lens arrays for autostereoscopic displays, tunable lenses for augmented reality goggles, auto-focusing spectacles, and smart contact lenses, mostly depend on one or more active optical components with the desired and controllable beam modifying functionalities, preferably manufactured at relatively low cost. Recent progress in research on components based on the combination of liquid crystals (LCs) and various polymer micro-structures is reviewed in this paper. It is found that such components can address the demands appropriately and have the potential of paving the way for large-scale applications of active optical beam shaping components.

Recently developed alignment techniques for liquid crystals enable the definition of arbitrary alignment patterns. We present a method to determine these two-dimensional spatial alignment distributions as well as the retardation of thin nematic liquid crystal films. The method is based on quantifying the influence of the birefringence of such a film on light with known input polarization by measuring the Stokes parameters of light. We show that we are able to distinguish arbitrary alignment patterns unambiguously. In addition, we demonstrate the ability to evaluate the homogeneity of the alignment as well as the thickness or birefringence of the film.

A wavefront calculation based on Zernike polynomials is applied to an optically addressed liquid crystal modulator for ultrafast laser machining.

Boron Neutron Capture Therapy (BNCT) is neutron radiotherapy used to treat tumours cells previously doped with Boron-10. This therapy requires an epithermal neutron beam for the treatment of deep tumours and a thermal beam for shallow ones. Thanks to recent high-current commercial accelerators, Accelerator-Based Neutron Sources (ABNS) are a competitive option for providing therapeutic neutron beams in hospitals. In this work, the neutron field generated by the Li (p,n)Be reaction at 1950 keV is studied as a neutron source in ABNS, being measured by the Time-Of-Flight (TOF) technique at HiSPANoS facility (Spain). Moreover, two Beam Shaping Assemblies (BSA) for deep and shallow tumour treatment, which are specially designed for the 1950 keV neutron field, are evaluated for BNCT via Monte Carlo simulations (MCNP). Results in agreement with the International Atomic Energy Agency (IAEA) figures of merit endorse the use of this neutron field for BNCT., The authors thank CNA technicians for their help during the experiment. We acknowledge the financial support for this work from the Spanish MINECO and FEDER funds under contract FIS 2015-69941-C2-1-P, FPA 2016-77689-C2-1-R, A-FQM-371-UGR18 (Programa Operativo FEDER Andalucıa 2014–2020), Asociación Española Contra el Cáncer (AECC) under contract PS16163811PORR, Junta de Andalucía under contract P11-FQM-8229, the founders of the University of Granada Chair Neutrons for Medicine: Spanish Fundación ACS and Capitán Antonio, US-1261006 (Proyectos I + D + i FEDER Andalucía 2014–2020), and RTI 2018-098117-B-C21 (MINECO). M. Macías acknowledges the FPI fellowship BES-2014-068808 granted in the project FPA 2013-47327-C2-1-R.

In this paper a low loss reflective surface for beam shaping with wide bandwidth is presented. In this reflective surface an orthogonal polarization is achieved with the use of a metallic symmetric unitcell. Simple fabrication, adjustment of reflective phase and low loss are the main advantages of this unitcell. With the use of this unitcell, a reflective surface with isoflux beam for satellite applications in X-band frequency is designed and the simulation and optimization results are presented. The bandwidth of the presented unitcell for designed beam is above the 120%.

Suture ligation of vascular tissues is slow and skill intensive. Ultrasonic (US) and radiofrequency (RF) devices enable more rapid vascular tissue ligation to maintain hemostasis, than sutures and mechanical clips, which leave foreign objects in the body and require exchange of instruments. However, US and RF devices are limited by excessive collateral thermal damage to adjacent tissues, and high jaw temperatures that require a long time to cool. A novel alternative method using infrared (IR) laser energy is being developed for more rapid and precise sealing of vessels. This study describes design, modeling, and initial testing of several optical beam shaping geometries for integration into the standard jaws of a laparoscopic device. The objective was to transform the circular laser beam into a linear beam, for uniform, cross-irradiation and sealing of blood vessels. Cylindrical mirrors organized in a staircase geometry provided the best spatial beam profile.Clinical Relevance—This study explored several optical designs for potential integration into the standard jaws of a laparoscopic vessel sealing device, transforming a circular laser beam into a linear beam for sealing of vascular structures.

The modification of transparent materials is enabled by focused ultrashort laser pulses. Single pass processing up to several millimeters can be achieved by the usage of elongated beam profiles. We studied the mechanical separability in dependence of the material thickness. As simulations show, asymmetric beam profiles can cause modifications with preferential direction reducing the necessary breaking force. Pump-probe microscopy is implemented to examine the laser-matter-interaction. We present a measured 3D-reconstruction of the transient interaction inside the material and elucidate the desired crack formation. We demonstrate beam shaping concepts to create a new, efficient and robust class of Bessel-like beams, which can be used to achieve a preferred crack direction. We verify the concept by modification and separation of silicate glasses.