Laser Proximity Sensor With Background Suppression

The PS1 from Eltrotec is a laser proximity sensor with an adjustable optic to set either a round or elliptical light spot in various sizes. Due to the switching frequency of 5kHz, the sensor can be used in assembly and supply systems running at high speed. PS1 is mainly used for controlling assemblies and presence of small parts as well as electronic components on printed boards, making high resolution an important feature and allowing detection of parts from 0.1mm and up.

These sensors are compact and easy to install and are similarly suited for breakage control in machine tools. The elliptical light-spot adjustment allows the sensors to reliably detect structured surfaces that otherwise may cause problems to small light spots. Adjustment and control is easy, as the red light shows a wavelength of 675nm, meaning it is visible. A mechanical potentiometer precisely detects on point 0.1mm. Sensing range varies from 55 to 300mm.

Because of its background suppression, the PS1 will not be affected by either clear or changing surfaces. Detection of light or dark objects can be selected. A switchable impulse extension secures signal transmission to control, reducing signal dropout by 40ms. Laser protection class of PS1 is DIN EN 60825-1 class 2, so no further protection activities are required. An IP 65 housing can be used for all industrial purposes and reliably works even in vibrating-equipment parts.

Newport Unveils Supercontinuum Laser Device

Newport has introduced a coherent anti-stokes raman scattering (CARS) optimised supercontinuum generation fibre device. Designed for use with 800nm femtosecond lasers, the SCG-800-CARS contains 12cm, highly nonlinear photonic crystal fibre with zero-dispersion points at 775nm and 945nm.

Two closely spaced, zero-dispersion wavelengths enable a stable, low-noise supercontinuum generation that also allows control of the spectral shape by tuning the pump wavelength. The fibre ends are sealed and mounted in quartz ferrules, with the polarisation axis aligned to a line on the end of the device. The nonlinear supercontinuum fibre is mounted in a robust, 25mm diameter, 120mm-long aluminum housing that can be mounted on a translation stage.

The pre-assembled product features a sealed end facet with beam expansion for easy coupling, making it suitable for spectroscopy and microscopy applications. The SCG-800-CARS will be exhibited at Newport's booth during SPIE Photonics West, from 26-28 January at the Moscone Center, San Francisco. It will be demonstrated as part of a Newport 'Wavelength Extension Unit for Ultrafast Oscillators' kit.

Q-Switched DPSS Laser Delivers 10W At 355nm

Newport Spectra-Physics has announced the latest addition to its Pulseo range of Q-Switched diode-pumped solid-state (DPSS) industrial lasers. The Pulseo 355-10 provides 10W of 355nm output at 90kHz with a short pulse width of less than 23ns. Key applications for the Pulseo 355-10 include crystalline silicon photovoltaic solar cell manufacturing processes such as wafer scribing and dicing, drilling and marking.

The high-power industrial laser is also suitable for microelectronics applications, such as via hole drilling, flex circuit cutting, flat-panel manufacturing, ITO patterning, LED substrate scribing, silicon wafer dicing/scribing and low K dielectric scribing. The Pulseo 355-10's short pulse width and high peak power, combined with higher repetition rates, reduce undesired thermal effects and results in higher throughput with less damage to the parts.

Tim Edwards, senior marketing manager for Newport's Spectra-Physics Laser Division, said: 'The design of the Pulseo 355-10 offers the same features as our other Pulseo range of products, including long life, excellent beam quality and stability, compact design and field-replaceable key components such as diodes, fibre and output window. 'This field serviceability, combined with reliability and global service and support, makes the Pulseo 355-10 suitable for high-uptime industrial applications,' he added.

Laser-Sintering Powders Target Aerospace Industry

Two powdered metals for the rapid manufacture of nickel alloy and aluminium alloy components by additive layer manufacturing have been introduced by EOS Electro Optical Systems. The company has specified the materials for use in its EOSINT M 270 laser-sintering systems. EOS nickel alloy IN718 is a nickel-based, heat-resistant super alloy, which corresponds to Inconel 718. It is a precipitation hardening, nickel chromium alloy characterised by good tensile, fatigue, creep and rupture strengths at temperatures up to 700C.

It shows high corrosion resistance, is suitable for many high-temperature applications and possesses strong cryogenic properties. The material may be of particular interest to the aerospace industry due to its demanding requirements. EOS said that it has carried out extensive tests in collaboration with several pilot customers. It has developed process parameters that enable good part building and ensure that the relevant industrial standards for this material type can be reliably fulfilled.

These include, for example, heat treatment in accordance with AMS 5662 and AMS 5664 standards, as well as tensile and stress rupture properties at elevated temperatures (650C). EOS aluminium AlSi10Mg powder, a typical casting alloy, is the first aluminium-based powder to be qualified for EOSINT M 270 systems and opens up application areas due to its light weight and thermal conductivity. Thorough process development and testing were performed as preparation for the launch. Cast parts in conventional AlSi10Mg are typically subjected to T6 heat treatment including solution annealing and quenching followed by age hardening at elevated temperatures.

EOS has already produced examples of laser-sintered aluminium alloy components illustrating intelligent designs such as hollow parts and mesh-like structures with high stiffness-to-weight ratios. The material is expected to open up new markets in the area of light alloys.

Trumpf Unveils Entry-Level CNC Laser Profiler

Trumpf has introduced an entry-level version of the Trulaser 3030 CNC New laser profiler. The Trulaser 3030 Lean Edition is aimed at manufacturers needing additional and expandable capacity or those who do not currently require high productivity but want to keep their options open for the future. The machine's capacity can be quickly and effectively boosted in line with customer demand thanks to a wide choice of options and retrofit possibilities, according to the company.

The Trulaser 3030 Lean Edition comes with all the technical advantages of the Trulaser 3030 New. The new entry-level version is equipped with a Truflow 3200 laser for cutting sheet up to 20mm and has simultaneous axis speeds of 140m/min. Faster processing is characteristic of the Trulaser 3030 New series and results in more parts being cut in the same amount of time and the reduction of power usage per part.

The laser's hibernation mode also contributes to the machine's overall energy efficiency. The single head, with collision protection, processes an entire range of material thicknesses. The Lensline lens monitoring system and Adjustline for the instant increase of material tolerance are both included in the standard package. The machine can be fed with sheets from the side or the rear.

The automation options start with an automatic pallet changer and include a range of possibilities from a simple Loadmaster loader through to a complete Liftmaster storage and automation system. For process optimisation, a premium cutting package is available as both an option and a retrofit. The components are Pierceline, Fastline and a spray unit that prevents material spatter from sticking.

Laser-Diode Modules Deliver Modulation At 200MHz

Vortran Laser Technology has announced the Stradus line of laser-diode modules that deliver digital modulation at 200MHz. The Stradus product line is available in popular wavelengths used for biomedical, RandD and laboratory applications. Wavelengths include 660nm at 100mW, 642nm at 110mW, 488nm at 50mW, 445nm at 40 mW, 405nm at 100mW and 375nm at 16mW.

Key features include M:1.25 (typical) and greater than 90 per cent circularity. All wavelength models offer RMS noise of less than 0.1 per cent from 10Hz to 10MHz and 0.2 per cent for 488nm. Beam dimensions are 1.3mm diameter for all wavelengths and the pointing stability is less than 5 urad/C. The Stradus range also offers power stability of less than 0.5 per cent for 24hrs.

All Stradus diode-laser modules are compatible with USB and RS-232 interfaces and offer alignment and pointing stability for demanding tasks in medical diagnostics, flow cytometry, defect analysis and other laboratory applications. Vortran's Stradus 488nm diode-laser module, featuring a 50mW output, is designed as an affordable alternative to standard, high-power-output diode-pumped, solid-state (DPSS) lasers. This model features digital modulation up to 200MHz, with analogue modulation at 500KHz.

Euromold To Feature EOS Laser-Sintering Systems

EOS will display its EOSINT P 395 and EOSINT P 760 plastic laser-sintering systems at this year's Euromold exhibition, to be held 2-5 December 2009. The modular nature of both systems allows for a high degree of flexibility. Individual modules can be excluded at first, reducing the initial investment, but can be added at any future time. Both systems also offer the option for upgrading, with substantially improved process modules to support the strategy of part property management. A re-engineered laser-optics module (surface module) improves the quality of vertical surfaces into regions that until now have been exclusive to Formiga parts.

The Eosint P 760 can be optionally equipped with OLPC, which monitors and controls the laser's power during the building process, ensuring a more constant power than was previously possible. The Eosint P 760 is available with Flashrecoating, a new x-axis control that increases productivity by accelerating the re-coating speed up to 400mm/s. With the appropriate packing density, build-up rates of up to 700cm/h are realistically achievable. The recoating unit in the Eosint P395 has also been improved.

The introduction of PPPs has led to the integration into the Eosint P 395 of EOS's successful blade-cartridge concept, which was introduced in the Eosint P 730 in 2007, making it simple to carry out adjustments and change the layer thickness. A new version of the Eostate software, which monitors and reports on laser-sintering production, will also be presented at Euromold. Eostate 1.2, with a new array of report and analysis options, is EOS's answer to the increase in demand for transparency and continuous quality assurance in series-production processes. As such, the software complements the PPPs perfectly and is available for all plastic and metal systems.

The standardised reuse of powder materials is a prerequisite for continuously sustaining high quality in ongoing production. To fulfil this, EOS has adapted the successful concepts of other product lines to develop an integrated process chain management (IPCM) for Eosint M systems. The most important step here in quality assurance is the fast sieving of powder under defined conditions before its reuse. The IPCM ensures vibratory sieving under defined conditions and mesh sizes adapted and optimised for individual powders.

Powder preparation outside the machine, for example via powder homogenisation, enables the highest quality as well as maximum productivity and flexibility. Further increases in productivity and user-friendliness can be achieved with EOS's IPCM modules for fast powder conveying and machine refilling. The IPCM product range includes multipurpose lifting trolleys for transporting powder containers, as well as for building platforms and clamping systems.

Laser Welding Suits Precision-Welding Processes

Laser Lines has explained the key advantages of laser welding. Nylon welding processes are split into two categories: low-energy-density, and high-energy-density processes. Low-energy-density processes are those such as traditional arc and resistance welding technologies that rely on heat conduction through the material from a surface point to provide melting. High-energy-density processes using lasers create a heating filament, known as the keyhole, which penetrates the depth and offers 2D line heating, causing a highly efficient heat transfer into the weld joint.

The key advantages of laser welding are a small heat-affected zone (HAZ), accurate control of heat input, and the ability to direct the beam precisely to the weld point. This means reduced thermal distortion, the ability to weld close to heat-sensitive parts, and precision welding capabilities. Major applications for sub-kilowatt lasers are in precision-welding and heat-sensitive welding processes, such as hermetic sealing, because the typical focused beam diameter of 100 microns localises temperature rises around the weld to fractions of an inch. These stainless-steel coupons were welded using the Firestar f400 laser. The 0.9mm (0.036in) thick stainless steel was fixtured with the ends tightly aligned to create a butt-type weld.

Because most laser-welding processes do not use filler wire, but instead rely on the molten material to create the weld joint, part fit-up for a laser weld must be free of any gaps or voids in order to achieve strong, consistent joints. As with conventional welding processes, creating initial spot welds at intervals along the joint helps to prevent material separation during the actual weld pass. Full weld penetration through the stainless steel was achieved using 400W of power at a weld speed of 1.9m/min (75in/min).

Beam delivery for this application was accomplished using a 63.5mm (2.5in) positive meniscus lens, which produced a 100-micron (0.004in) spot and 1.8mm (0.07in) depth of focus. During welding, argon shield gas at a flow rate of 1.0 SCFM prevents the molten weld pool from reacting with the surrounding atmosphere. At this material thickness and weld speed, there is no difference between argon and helium assist. When welding thicker stainless material at higher speeds, helium shielding provides deeper weld penetration due to its higher ionisation potential and smaller weld plume.

Newport Spectra-Physics Expands Hippo Laser Family

Newport Corporation's Spectra-Physics Lasers Division has added the Hippo 532-14 to its Hippo family of Q-switched diode-pumped solid-state (DPSS) industrial lasers. The Hippo 532-14 provides 14W of 532nm output at 100kHz with a short pulse width of less than 30ns.

Used for solar thin-film scribing applications, the laser is suitable for the high-speed, multi-beam scribing of P2 and P3 layers in thin-film a-Si and CdTe photovoltaic structures. Scribe speeds in excess of 12m/s have been achieved on tandem-junction a-Si P2 layers with isolation lines 65 microns wide and 2.5 microns deep. Features of the Hippo 532-14 include its short pulse width (less than 30ns at 100kHz) and high peak power (up to 16kW at 50kHz). Both help to reduce undesired thermal effects such as heat-affected zones, material recast and the micro-cracking of a substrate.

The pulse-to-pulse stability of the Hippo 532-14 at higher pulse repetition rates (up to 200kHz) translates to good scribe consistency at high processing speeds on solar panels, according to the company. The TEM00 beam profile and beam quality (M2 less than 1.3) translates to a larger depth of field for the Hippo 532-14, making it more forgiving of variations in glass substrate flatness and surface irregularities.

With proprietary Eternalign permanent optics mounting technology and field-replaceable key components such as diodes, fibres and harmonic modules, the Hippo 532-14 is rugged and has a low cost of operation. The Hippo 532-14 laser was showcased at Laser World of Photonics 2009 on 15-18 June in Munich, Germany.

Precision Micro Invests In Laser Direct Imaging

Precision Micro, a West Midlands-based specialist photochemical machining (PCM) company, has installed laser direct imaging (LDI) in its quest for continuous process improvement. PCM is the process of manufacturing sheet-metal components using a photo resist and etchants to remove the unwanted material.

The process can accurately produce highly complex parts with very fine detail and can provide an economical alternative to stamping, punching, laser or waterjet cutting or wire electrical discharge machining (EDM) for thin gauge precision parts. 'Next-generation' LDI is used in the manufacture of minute advanced electronics components. LDI is said to have already provided benefits to customers, allowing them to develop designs that were previously prohibitive on either technical or economic grounds.

Anthony Marrett, managing director, said: 'LDI has enabled us to deliver rapid prototyping even quicker and tool modifications can be carried out in a matter of minutes. 'Dimensional and positional accuracy across large formats are at new levels with a fourfold improvement in pitch accuracy across an 800mm x 600mm sheet. 'We have also noted that the improved capability has led to substantial yield improvements,' he added.

The LDI system is reported to have created an increase in demand for tight tolerance components as a result of the machine's ability to image ultra-fine, 15-micron features. Its charge-coupled-device (CCD) cameras and image recognition system also provide exceptionally precise front-to-back feature alignment. Precision Micro is believed to be the first specialist etching operation to utilise the LDI process.

Laser Lines Marks Code On Tiny Area Of Oil Seal

Laser Lines has recently marked a 10-character code on the outer ring of a customer's oil seal. At the 10.6 micron CO2 wavelength, rubber materials mark very well, but the unusual aspect of this mark was the size of the mark area on the outer ring: it measured only 1.25mm (0.049in) high. The marking set-up consisted of a Synrad laser, FH Flyer marking head and the Synrad Winmark Pro laser-marking software.

The FH Flyer head was equipped with an 80mm focusing lens that provides a 116-micron spot with a 0.8mm depth of field. To create legible text marks, the rule of thumb is that character height should be a minimum of seven-to-ten times the focused spot size. For this application, the character code was 1mm high, which is on the low-end of the range for an 80mm lens. To create this mark, the 'Simple' stroke font was selected, a text height of 1mm was set, 0.15mm of extra character spacing was added, and a text radius of 54mm was entered to match the curvature of the seal.

On the marking tab, power was set with a duty-cycle percentage equal to 10W; a velocity of 1016 millimetres per second was added, and the mark-passes property was set to four. By making four complete passes, the rubber surface is vaporised slowly in small increments, resulting in a cleaner, more distinct mark. The characters are well-formed; the engraved 1mm-high text can be easily read without magnifying aids. This small 10-character code, with four mark passes, was created in a cycle time of only 0.13 seconds per part.

Laser Cutting Provides Better Gas Flow

In several development steps with cutting trials, Precitec has increased the flow rate through the cutting nozzle while keeping the cutting gas pressure constant. The KT B CON ceramic part and the nozzles now have no 'hard edges' and have a conical geometry. Thus, the cutting gas pressure can be reduced while giving the same cutting edge quality and the input pressure directly on the processing head can be reduced.

The company said that field tests with the new design have also shown an increased working range for the focal position. Dirt on the focussing lens and the associated focus shift can be detected with the larger process window and increase the operating life of the optics. With CO2 cutting heads without a protective window in particular, this leads to cost advantages.

Synrad CO2 Laser Welds Polyethylene Film

Synrad's sealed CO2 lasers are used in a variety of industrial processes including cutting, welding, drilling and marking. Because CO2 lasers have very consistent output power and the heating process is always non-contact, laser-formed seals will remain consistent over hours of operation. For this particular application, which required sealing 0.05mm-thick polyethylene film, a Synrad 50W laser was used in conjunction with an XY table and a cutting head outfitted with a 63.5mm focal length lens.

This lens typically provides a 0.1mm focused spot size; however, for laser sealing operations, a larger spot size is often preferred. A larger spot size yields lower overall power density and leads to increased melting and less vaporisation of thin films. It also increases the weld line width, providing better weld strength.

For these reasons, the lens was unfocused slightly by increasing the standoff distance to around 5mm between the surface of the film and the tip of the cutting head, to obtain a 0.5mm-wide weld line on the plastic film. The cutting head traversed two layers of the film at a speed of 12.7m/min to produce the final finished seal. The resulting seal is consistent in strength across its entire length.

Rofin DQ 010 Q-Switched Laser Outputs 1kW Of Power

Rofin has added the DQ 010 to its range of high power DQ Q-switched solid-state lasers. The high-performance lasers of the DQ series are suitable for surface applications such as ablation, cleaning and insulation, with other applications currently in development. The 1kW output power and increased pulse peak performance of the DQ 010, which are 1,000 times higher than CW powers, reduce cycle times and ultimately operating expenses. The DQ 010 can be integrated with beam switches or power-splitter modules, allowing the use of one beam source in several different production lines.

This reduces initial investment cost, while the increased efficiency of the beam source lowers the ongoing running costs. The high average power makes it an efficient tool for selective material removal. It is ideal for solar-panel ablation, mould cleaning, material coating removal and surface-treatment of flat screens. The DQ series can offer power ranges of 500, 800 and 1kW. The ablation of the aluminium-silicon coatings from manganese-boron tailored blanks is a typical application where Rofin DQ series lasers offer an effective alternative to traditional sand-blasting or chemical-etching processes.

Compared with conventional steels, the tensile strength of these steels, especially following heat treatment, is much greater, reducing material thickness without reducing the strength of the finished part. The automotive industry has been using these features to reduce weight, which in turn reduces fuel consumption and helps protect the car. The aluminium-silicon coating had prevented these materials from being used for tailored blanks. The reason aluminium-silicon coating is applied to these steels is that a zinc coating would vaporise at the temperatures (in excess of 900C) required for processes such as hot stamping on these materials.

This would leave the material susceptible to scaling and corrosion. The aluminium-silicon coating however does have its own disadvantages, as it combines with the base material during laser welding and therefore must be removed prior to welding. Rofin DQ series Q-switched lasers can remove the aluminium-silicon coating from manganese-boron steels at impressive rates. The lasers can be coupled with fibre optics of 600 or 800 square-microns.

Compared with round fibres, square fibres provide the highest efficiency by machining a larger area for each pulse. Combined with an integrated scanner, ablation rates up to 100cm2/s are achievable across a diverse range of applications. Every DQ laser is equipped with an optical attenuator for constant pulse energy and long-term stability control. This key feature optimises application processes by ensuring that the pulse energy remains constant. The new DQ 010 will have its debut at the Laser fair in Munich from 15-18 June 2009.

Rofin Introduces High-Power Fibre Laser Series

Rofin-Sinar Laser has announced the FL series of high-power fibre lasers. The FL series offers two models; the FL x75 and FL 010, with output powers of 750 and 1,000W respectively. The series has high beam quality and can be coupled in fibre optics with diameters of 50um up to 600um. This is equivalent to beam qualities of 2.5 to 30mm x mrad. The Rofin FL 010 S offers a fibre laser option with single-mode beam quality of typically 0.4mm x mrad and 1,000W output power.

The Rofin FL series is suitable for a wide range of applications. Small parts can be welded with low thermal distortion and minimal heat-affected zones, and steel or aluminium can be joined with welding depths of several millimetres. The high beam quality allows the efficient use of 'dynamic beam' scanner systems, allowing 2D and 3D geometries to be processed.

Optional beam switch and energy share modules provide the greatest use of the beam source. A single laser can be used in up to four individual work cells. These features support increased cycle times and productivity while minimising capital equipment costs. FL lasers are easily integrated into new and existing production workcells. The lasers of the FL series are designed for low-maintenance operation and long-term performance.

Unlike other concepts, where the laser beam changes repeatedly between air and the laser active medium, the beam of a fibre laser does not leave the fibre optics before the 1 processing optics (single-mode) or the beam switch (multi-mode). This 'all-in-glass' technology reduces the risk of optical contamination and eliminates changes in beam quality. The FL series will be presented at the Laser fair in Munich from 15-18 June 2009.

Laser Sintering System Produces Dental Implants

EOS's EOSINT M 270 laser-sintering system can manufacture dental implants by direct metal laser sintering (DMLS) using a focused solid-state laser. The Millenium Research Group estimates that the European market for crowns and bridges will grow annually by an average rate of eight per cent until 2012. Technological advancements in the field of dental care are contributing to this by employing production methods such as laser sintering to provide dental restorations, which are more affordable, more readily available and of high quality.

Until now, dental implants have traditionally been made out of metal via a casting process. This process enabled a technician to produce 20 dental frames per day. One automated laser-sintering machine can produce up to 450 parts for dental crowns and bridges within 24 hours, and all of the finished parts will be of the same quality. The tasks of deflasking and cleaning moulds are dispensed with, thus allowing the dental technician to concentrate on a core competence, namely the post-processing of the metal structure and its aesthetic upgrade: ceramic veneering. EOS's EOSINT M 270 laser-sintering system can be used to manufacture dental implants.

The machine uses CAD data to produce, from metal powder and in only a few hours, complex geometries that exhibit excellent mechanical properties, surface quality and detail resolution. The CE-certified EOS Cobaltchrome SP2 alloy was developed by EOS especially for the dental industry for use in the EOSINT M 270. EOS demonstrated the entire process chain at the 33rd International Dental Show (IDS) from 24-28 March 2009 in Cologne. All the steps involved in laser sintering crowns and bridges were shown, from the initial scanner to the creation of the 3D CAD data and the laser-sintering machine, and ending with the finished veneered product.

The further development of dental CAD/CAM applications with new impression and intra-oral scanners will make it possible to send high-quality data directly to the processing centre. The only thing missing would be a dental model for occlusion testing and post-processing, or a workpiece holder for use during veneering. Such a model can be laser sintered on a Formiga P 100 from PA 2200, a quality plastic, on the basis of already available data. Laser sintering provides a complete solution for the manufacture of dental implants.