Method and devices using lasers to reduce reflection of transparent solids in the optical spectrum, coatings and devices employing transparent solids are disclosed. The lasers are used to shape surfaces of the transparent solid materials by raising the temperature of the material to around the melting temperature, and thereby generate desired target nanostructure two-dimensional antireflection flection pattern arrays on the surfaces. The laser fluence value, wavelength, repetition rate, pulse duraction and number of consecutive laser pulses per focus spot are selected, and a desired focus spot distribution on the surface of the transparent solid material is identified. The transparent solid material is relatively translated to generate the desired nanostructure two-dimensional pattern array.

The invention relates to a process for nanostructuring the surface of a solid material in order to form a regular pattern of nanostructures on said surface, comprising: irradiating the surface by a plurality of pulse trains (20) of a femtosecond laser beam: each pulse train (20) comprises at least two pulses (21, 22), each pulse has a peak fluence, and a sum of the peak fluences of the pulses of a pulse train is between 10% and 70% of a threshold fluence corresponding to a material ablation threshold for one pulse for said material, two consecutive pulses of a pulse train are separated by a peak-to-peak duration ΔT between 500 fs and 150 ps, two consecutive pulse trains are separated by a duration greater than 10 ΔT, obtaining a regular pattern of nanostructures on said portion of surface, having a spatial periodicity lower than 130 nm.

Method for structuring a top surface of a transparent substrate, the substrate being transparent to visible light with a laser source able to emit a laser beam in a burst mode, the burst mode being characterized by a train of pulses comprising sets of laser pulses repeated over time; wherein each of the sets of laser pulses of the train of pulses comprises a first and second pulses with a time interval between them comprised between 5 ns to 50 ns, preferably between 10 ns to 40 ns, and more preferably about 25 ns; wherein each of the first and second pulses has an energy density on the top surface comprised between 0.5 nJ/um.sup.2 and 50 nJ/um.sup.2; and wherein the train of pulses is able to structure the top surface.

A hydrophilic surface pattern on a removal surface of a steam turbine directs surface moisture in at least one predetermined direction to enhance moisture management by enhancing moisture removal or otherwise reducing erosion caused by moisture in the steam turbine. In some embodiments, the removal surface is located on the outer surface of the nozzle wall adjacent an extraction opening. In some embodiments, the removal surface is located on the surface of the bucket and directs moisture toward the turbine rotor. In some embodiments, the removal surface is located on the surface of the turbine casing or the surface of the nozzle and directs moisture toward a drain in the turbine casing. The hydrophilic surface pattern is preferably laser-etched as a nano-scale pattern to create the hydrophilic surface. In some embodiments, the hydrophilic surface pattern creates a superhydrophilic surface.

A method for forming a defined surface roughness in a region of a component that is to be manufactured or is manufactured additively includes setting an irradiation parameter and/or an irradiation pattern in such a way that a component material is provided with a certain porosity in the region under a surface of the component, which porosity is suitable for causing the defined surface roughness in the component. A corresponding component is also specified.

Provided is a mask assembly including a mask sheet including a pattern part with at least one opening part, and a welding part connected to the pattern part, and a mask frame with the mask sheet mounted thereon and welded to the welding part. The mask sheet includes a first surface configured to fact the mask frame and a second surface opposite to the first surface. The welding part includes a hatching area in which a surface roughness of the second surface is larger than that of the second surface in the pattern part.

A system and method of planarizing a layer are disclosed. Topography of the layer is measured to produce a topographic map, which is then digitized into blocks of that indicate different thickness variation. Laser conditions are assigned for each block, a laser steered to planarization blocks where material is to be removed, and the material ablated at each planarization block. In-situ monitoring of the surface profile provides feedback to adjust the laser conditions during planarization. When depth control is used, the laser is focused at a focal plane and has a focal depth beyond which no material is ablated and the laser is steered across the entire layer. A thin metal layer of higher ablation threshold than the dielectric layer formed over the layer provides added selectivity, with the laser conditions changed after ablation of the metal layer. Otherwise, planarization is limited to the planarization blocks.

The invention describes a method for engraving, marking and/or inscribing a workpiece (7) using a laser plotter (2). In said method, in a housing (3) of the laser plotter (2), one, preferably more, in particular two laser sources (4) in the form of lasers (5, 6) have an effect preferably alternating on the workpiece (7) to be processed. The workpiece (7) is laid in a defined manner on a processing table (9) and a laser beam (10) emitted from the beam source (4) is transmitted to at least one focusing unit (12) via deflection elements (11) and the laser beam (10) is diverted toward the workpiece (7) and focused for processing. The workpiece (7), in particular the position of the work piece in relation to the laser beam (1), is controlled by means of software running in a control unit (13), such that the workpiece (7) is processed line by line by the displacement of a carriage (21). A sequence control adapted to the quality of the engraving in which a defined ratio of a spot variable (23) to the line distance and an engraving controller (1) of the lines (22) to be processed is determined and/or carried out by the control unit (13) and the focusing unit (12) on the carriage (21) is controlled corresponding to the defined parameters of the sequence control.

A metal foil with a karstified topography having a surface morphology in which a maximum peak height minus a maximum profile depth is greater than 0.5 m and extends into the surface at least 5% of the foil thickness, a root mean square roughness is at least about 0.2 m measured in a direction of greatest roughness, and an oxygen abundance is less than 5 atomic %. The foil may be composed of aluminum, titanium, nickel, copper, or stainless steel, or an alloy of any thereof, and may have a coating composed of nickel, nickel alloy, titanium, titanium alloy, nickel oxide, titanium dioxide, zinc oxide, indium tin oxide, or carbon, or a mixture or composite of any thereof. The foil may form part of a metal electrode, current collector, or electrochemical interface. Further described is a method for producing the foil by laser ablation in a vacuum.

A method for integrally bonding a cast aluminum component to a joining partner. The method includes laser-treating a region of the cast aluminum component that is to be connected to the joining partner. The laser treatment is carried out via a pulsed laser system having a pulse duration of 100 to 200 ns, and an impulse frequency of 10 to 80 kHz. The method also includes integrally bonding the cast aluminum component and the joining partner.