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Focus on lasers and optics

QCW bars and stacked arrays

Intense Ltd has developed passively mounted quasi-continuous-wave bars with power levels in excess of 300 W and has added to its Hermes stacked array line higher-power QCW products, from 1200 to 2000 W. The company’s quantum well intermixing technology increases brightness and reliability and eliminates the problems associated with catastrophic optical mirror damage. In addition, a new “H”-style mounted bar is designed specifically for high-power, high-efficiency, rod-pumping applications and can be used in its standard configuration or fitted with either a slow or fast axis collimator lens. The Hermes family is available in a range of wavelengths suitable for direct diode pumping, illumination, and material processing. The company offers bars and stacked arrays with various macro- and microlenses to integrate drive electronics into higher-level diode modules or packs. Intense Ltd, 1200A Airport Road, North Brunswick, NJ 08902, http://www.intenseco.com

Compact DPSS lasers

Cobolt AB has introduced two new CW diode-pumped solid-state lasers. The Cobolt Twist, with up to 50-mW output power at 457 nm, provides a compact and power-efficient alternative to the 458-nm line used in argon-ion lasers. It is a single-mode device with a low noise of less than 0.3% rms, a narrow spectral line width of less than 10 MHz, and a high beam quality of M² less than 1.1. The Twist is well suited for demanding fluorescence applications, such as those used in confocal microscopy and for certain reprographics and display uses. The Cobolt Zouk provides 10 mW of output power at a wavelength of 355 nm and with a perfect TEM₀₀ beam. It offers an alternative to argon- and krypton-ion UV lines and quasi-CW UV lasers and is ideal for applications in flow cytometry and confocal microscopy. Cobolt lasers are based on periodically poled potassium titanyl phosphate frequency conversion technology. Cobolt AB, Vretenvägen 13, SE-171 54 Solna, Sweden, http://www.cobolt.se

High-power laser diode drivers

NewsportCorp 5700 series

Newport Corp has announced the 5700 series of high-power laser diode drivers that feature CW or pulsed-current mode of operation with the option of either local or remote control. Two of the four models are designed for use with single-bar multiemitter laser diodes and offer 30 A/5 V and 80 A/7.5 V outputs. The other two models, for stacked multibar, multiemitter lasers, use a 3-kW power supply and provide outputs of 100 A/30 V and 150 A/20 V. The USB 2.0 interface—software drivers are included with the instruments—allows for full light-current-voltage characterization of laser diodes. Comprehensive laser diode protection is provided through transient filtering, intermittent contact protection, independent current limit and power limit settings, and a slow turn-on sequence. When the instruments are powered off, program settings are saved in the nonvolatile memory. Newport Corporation, 1791 Deere Avenue, Irvine, CA 92606, http://www.newport.com

Ultrafast amplifier system

The Libra-HE from Coherent Inc is a one-box ultrafast Ti:sapphire amplifier that delivers significantly higher pulse energy and shorter pulse width than earlier Libra models. The new system produces pulse energies of more than 3.5 mJ at 1 kHz and offers a choice of either 50- or 100-fs pulse width models; it comes with a standard pulse repetition rate of 1 or 5 kHz at 800 nm. The Libra-HE provides improved beam quality with M² less than 1.3 because it uses Coherent’s next-generation E-2 engine-regenerative amplifier design in concert with the high-power capabilities of the company’s Evolution pump platform. That combination results in an output stability of better than 0.5%rms. The high-power and short-pulse width of Libra-HE will be useful for pumping multiple, tunable, optical parametric amplifiers in pump probe experiments and for ultrafast spectroscopy techniques. Coherent Inc, 5100 Patrick Henry Drive, Santa Clara, CA 95054, http://www.coherent.com

Laser for microablation

Andor’s ALC-UVP-350i is a computer-controlled UV pulsed laser source designed to improve applications involving the microablation of subcellular organelles and molecular uncaging. The source operates at 350 nm with a repetition rate from 1 Hz to 5 kHz and pulse energy up to 60 μJ, variable over more than four decades. UV pulses are delivered over a multimode, 25-μm optical fiber, ensuring safe and convenient coupling to optical microscopes via a dichroic coupler manufactured by Meopta-optika sro. With a spot size down to 2.5 μm and high-aperture objectives, precision targeting can be achieved. The ALC-UVP-350i, a new addition to the company’s Revolution laser-spinning disk confocal system, which allows simultaneous imaging and ablation or uncaging, is designed to help biologists perform more precise microsurgery and optical activation with live cells. Andor Technology PLC, 7 Millennium Way, Springvale Business Park, Belfast BT12 7AL, UK, http://www.andor.com

Micromirror array

IMEC Micromirror array

IMEC is offering a monolithically integrated 11-megapixel micromirror array for high-end industrial applications. Each mirror is 8 μm × 8 μm and can be individually tilted by the high-speed CMOS circuitry underneath the 10 cm² array, which has a pixel density that is almost double that of comparable micromirrors. The mirrors are fabricated on top of foundry high-voltage 0.18-μm CMOS 200-mm wafers with six interconnect levels. A top view of individual mirrors and hinges is shown in the photo. The array was built using the company’s silicon germanium–based MEMS platform. Because of its reliability, polycrystalline SiGe, rather than aluminum, was chosen as structural material for the mirrors. The company has demonstrated that its mirrors show no creep and meet a 10¹² cycles mechanical lifetime. Arrays such as this one are used in, for example, video projection and lithography mask writers. IMEC, Kapeldreef 75, B-3001 Leuven, Belgium, http://www.imec.be

Pulsed multiwatt laser

Teem Photonics has brought together passively Q-switched microchip technology with fiberoptic amplification, resulting in the PicoSpark laser, which produces pulses with energies of hundreds of microjoules at repetition rates of a few tens of kilohertz. The average output power is several watts, with hundreds of kilowatts of peak power. The PQS microchip, the basis of the new laser, sets the pulse width in the hundreds of picoseconds. The master-oscillator fiber-amplifier architecture allows both the pulse width to stay constant and users to vary the pulse energy (or peak power) and the repetition rate independently of each other. The PicoSpark is available at operating wavelengths of either 1064 or 532 nm. With its TEM₀₀ beam quality and very high irradiance—700 GW/cm² at 25 kHz at 1064 nm—it is ideal for hard materials processing. Teem Photonics Inc, 3594 Nyland Way, Suite TP1, Lafayette, CO 80026, http://www.teemphotonics.com

Multilaser device for aesthetic procedures

Sciton has introduced the Joule aesthetic laser platform, which offers a combination of multiple laser wavelengths delivered through any of the device’s three delivery modes—arm, fiber, or broadband light. A single platform can now provide laser-assisted lipolysis, deep and fractional skin resurfacing, hair removal, and a range of vascular treatments. The company calls the technology OptiPlex, the optimal multiplexing of optical technologies. In addition to any combination of the three delivery modes, Joule has four laser bays and a pulsed light bay; for cosmetic procedures, it offers a comprehensive selection of modules and the ability to add future ones. The platform currently has nine modules, including Contour TRL, a 2940-nm laser to administer the company’s MicroLaserPeel procedure; ClearScan, a 1064-nm system to treat pigmented and vascular lesions; and the IR-light SkinTyte accessory to firm tissue. Sciton Inc, 925 Commercial Street, Palo Alto, CA 94303, http://www.sciton.com

Laser beam analysis system

Ophir-Spiricon BeamGague

Ophir-Spiricon’s BeamGage includes all the accuracy and ISO-approved quantitative results that make the company’s LBA and BeamStar software so successful. The performance of today’s laser systems depends on knowledge of a beam’s size, shape, uniformity or approximation to the expected power distribution, and its divergence and mode content. Ophir-Spiricon’s UltraCal algorithm guarantees the baseline or zero-reference point and is accurate to 1/8 of a digital count on a pixel-by-pixel basis; UltraCal has been enhanced in BeamGage to ensure that accurate spatial measurements are more quickly available. The new system incorporates BeamMaker, which can synthetically generate beam profile data and allows users to model laser beams in various modal configurations. BeamGage can interface with the company’s power meter so that laser power readings can match beam profile data. Ophir-Spiricon Inc, 60 West 1000 North, Logan, UT 84321, http://www.ophir-spiricon.com

Harmonic separating beamsplitters

Saint-Gobain Crystals has announced a series of harmonic separators, optimized for use with solid-state lasers. The new Alpine Research Optics–brand products are all-dichroic beamsplitters for either splitting or combining the various harmonics of Nd:YAG and Nd:YVO₄ lasers. Both short- and long-wave pass designs are available. Beamsplitter coatings are typically supplied on flat substrates with a high-efficiency, antireflection coating on the second surface. Near-IR and visible wavelength optics are offered on optical grade fused silica substrates; optics for UV wavelengths are fabricated on UV grade fused silica substrates. Flatness at 633 nm is »/10, and 10^-5 surface quality is provided. Because of their combination of high-damage threshold and mechanical durability, the optics are useful in demanding applications. Saint-Gobain Crystals, Alpine Research Optics, 6810 Winchester Circle, Boulder, CO 80301, http://www.arocorp.com

Fiber-coupled diode lasers

The nLight Corp has expanded its Pearl fiber-coupled solid-state laser platforms into wavelengths of 879 to 888 nm with electrical-optical efficiency greater than 50%, producing significantly less heat. Power levels up to 100 W are available at 879, 885, and 888 nm and exploit the company’s 400- or 600-μm PowerCore fiber. When used for upper-state pumping of Nd:YAG or Nd:YVO₄, Pearl allows the design and manufacture of air-cooled, diode-pumped solid-state laser systems. Pearl’s unique single-emitter architecture helps maintain narrow spectral widths of less than 3.5 nm (full-width at half-maximum). The company’s nXLT diode technology enables Pearl to operate over a long lifespan, even under harsh industrial conditions with repeated on–off cycles. The PowerCore fiber provides consistent beam quality and power transmission independent of fiber layout and movement. nLight Corporation, 5408 NE 88th Street, Building E, Vancouver, WA 98665, http://www.nlight.net

Optical trigger

The OT-2 optical trigger from Specialised Imaging can be used as a general-purpose optical detector that senses either a bright flash of light or an object moving across its field of view. The device, sensitive from 300 to 700 nm, combines a unique multisegment photodiode array with both high- and low-pass filtering. The OT-2 is battery driven, so it is immune to the electrical noise produced when a gun is fired or other high-voltage instrumentation is triggered. It has a viewfinder that allows users to accurately focus on the point of the bright flash or where an object passes its active area. The trigger provides reliable detection of projectiles greater than 0.70-mm o.d. and offers the option of interchangeable lenses to ensure at least 1/20 obscuration of the field of view. Specialised Imaging Ltd, Unit 32, Silk Mill Industrial Estate, Brook Street, Tring, Hertfordshire, UK HP23 5EF, http://www.specialised-imaging.com

Blue laser diode

Osram Opto Semiconductors has developed a new blue laser diode with a wavelength of 450 nm and an output power of 50 mW; it operates at 5.5 V. It has all the essential attributes for a microprojector, including small size (3.2 mm in height), an efficiency of 0.9 W/A, and excellent blue light visibility. As a ridge laser, it also has outstanding beam quality and requires only simple optics to shape the beam. Lasers are ideal as light sources for mobile devices such as cell phones and digital cameras; the lasers can convert the mobile devices into high-performing, multifunctional ones that can record images that have razor-sharp detail. Lasers also offer exceptionally vibrant colors and high contrast, and they produce sharp images, independent of the distance over which the images are projected. Osram Opto Semiconductors Inc, 2650 San Tomas Expressway, Santa Clara, CA 95051, http://www.osram-os.com

Ultrafast multipass amplifier

Femtolasers Produktions has introduced the Femtopower compact PRO HE, an ultrafast Ti:sapphire multipass amplifier that uses a sealed vacuum chamber system for the amplifier crystal and dispersive mirror (DM) technology for dispersion compensation. The amplifier generates what the company claims is the shortest high-energy optical pulses commercially available. The system produces sub-35-fs pulses at a repetition rate of 1 kHz, an output energy of greater than 1.6 mJ, and a peak power of greater than 40 GW. The amplifier crystal is cooled in a vacuum chamber, and the new evaporation cooling system ensures reduced thermal lensing. Over 15 hours, the power drift is ±1.5% and the pulse energy is stable to 1.5% rms. DM technology allows the elimination of standard diffraction gratings. Femtolasers Inc, 124 Mount Auburn Street, Suite 200 North, Cambridge, MA 02138, http://www.femtolasers.com

Fiber-optic components

Fiberguide Industries is offering a line of standard fiber-optic collimators and focus guides for use with various optical systems. Designed to collimate or focus light exiting a fiber to a desired beam diameter, the components can be used with laser diodes, photodiodes, acousto-optic modulators, and other fiber-optic devices. Focus guides thread into the collimator and refocus the beam at a given distance; the guides and collimators can be used as matched pairs. The modules accept SMA, ST, FC, or machined ferrule-style connectors. Collimators come in three sizes: macro for fiber-core sizes larger than 800-μm o.d., midsize for diameters up to 800 μm, and micro for fibers up to 400 μm. Focus guides are available for the macro and midsize collimators. The devices have focal lengths from 10 to 76 mm and incorporate silica or BK-7 lenses. Fiberguide Industries, 1 Bay Street, Stirling, NJ 07980, http://www.fiberguide.com

New literature

CVI Melles Griot has published its 2009 catalog with details and specifications on such products as optics, lasers, laser beam and spectral measurement tools, machine vision systems, shutters, optical tables, microscopes, apertures and spatial filters, forensics equipment, and lab accessories. CVI Melles Griot, 200 Dorado Place SE, Albuquerque, NM 87123, http://www.cvimellesgriot.com