PHOTONICS WEST PREVIEW

GAIL OVERTON, JOHN WALLACE,

and BARBARA GOODE

Twenty-thousand photonics technologists and executives will unite at the 2015 SPIE Photonics West conference this February in San Francisco to explore, among many other things, how photonics could potentially improve, repair, and communicate with the brain using light.

The BiOS Hot Topics session is

a not-to-be-missed favorite presenting some of the most important recent developments in biophotonics on Feb. 7 from 7 to 9 pm.

for Optoelectronics— presentations will represent not only the latest work, but a heightened sense of direction and

reaching implications for the future of our society.

Imagine being able to probe, study, and even modify the brain’s behavior using light (can you say “optogenet- ics”?). Now envision using light to print brain matter and other biological tissues for life-saving repairs and mindaltering benefits (are you thinking “3D printing”?). And finally, imagine using light to communicate faster than ever before using ultra-tiny circuits that circumvent cumbersome, bulkoptic devices and interconnect bottlenecks with faster-than-light photonic

SPIE Photonics West will draw a crowd of over 20,000 engineers, scientists, and students to Moscone Center in San Francisco from

February 7-12, 2015.

Tissue Optics, Laser-Tissue Interaction, and Tissue Engineering; and Biomedical Spectroscopy, Microscopy, and Imaging. In addition, Translational Research is a virtual symposium that includes BiOS presentations in

all five tracks—on technologies, tools, and techniques that show high potential to improve

healthcare practice.

If past years are any indication, even after a full day exploring the conferences, exhibits, and interactive poster session, attendees will bring enthusiastic attention to the Saturday Hot Topics plenary (7–9 pm). Hot Topics will begin with presentation of SPIE’s 2015 awards in biomedical optics, including the Biophotonics Technology Innovator Award (as of late November, the winner had not been announced) and the Britton Chance Biomedical Optics Award, which will honor Lihong Wang of Washington University (St. Louis, MO) for “outstanding lifetime contributions” (see Fig. 1). Wang is being recognized for his pioneering technical work and visionary leadership in the development and application of photoacoustics and photon transport modeling; he will deliver a talk titled “Photon-Phonon Synergy: Photoacoustic Tomography and Beyond.”

Next, seven other speakers will take the stage. Three of these will focus on cancer screening and treatment: Vadim Backman of Northwestern University will speak on cancer screening and nanoscale cytology; Paola Taroni of Politecnico di Milano (Italy) will explain optical assessment of collagen and breast cancer;

PHOTONICS WEST PREVIEW c o n t i n u e d

SA’s (Muzzano, Switzerland) tabletop platform for making 3D micro-nano- devices; a free-running single-photon detector for the near-IR range from ID Quantique (Geneva, Switzerland); and Raptor Photonics’ (Larne, Northern Ireland) cooled visible-SWIR InGaAs camera. In case you don’t get to see all the vendors you want to on Saturday and Sunday, keep in mind that some will also exhibit in the Photonics West Expo starting Tuesday.

Two special events are set to begin Sunday at 12:30: the BiOS Student Networking Lunch with the Experts and the Translational Research Lunchtime Forum. The latter will feature Bruce Tromberg of UC Irvine and Gabriela Apiou of Harvard Medical School facilitating a discussion about outcomesbased work that can change the lives of patients, presentations of work selected from the Translational Research virtual symposium, and Best Paper awards.

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assessment of bone health (a technologically difficult task), by Xueding Wang of the University of Michigan Medical School and colleagues.

2.Paper 9308-18: Enabling technology for photodynamic therapy in global health settings: Battery-powered irradiation and smartphone-based imaging for ALA-PDT by Joshua Hempstead of the University of Massachusetts (Boston) and colleagues. Photonics has much to offer global health, and this is an exciting new example.

3.Paper 9311-7: Quantitative wide-field fluorescence imaging in neurosurgery by Keith Paulsen of the Thayer School of Engineering at Dartmouth College and colleagues. Wow: fluorescenceguided neurosurgery.

4.Paper 9334-22: Lattice light-sheet microscopy: Imaging molecules, cells, and embryos at high spatiotemporal resolution by Wesley Legant, Howard Hughes Medical Institute, Janelia Farm Research Campus and colleagues. This technique represents recent work by Nobel Laureate Betzig (see Fig. 3).

LASE

The LASE plenary session, held Wednesday, includes presentations on the future of NASA’s optical communications program by Donald Cornwall Jr., head of NASA’s Advanced Communications Division; coherent combination of ultrafast laser pulses by Jens Limpert, head of the Laser Development Group at Friedrich-Schiller-Universität Jena (Germany); and laser 3D printing of metallic components by Xiaoyan Zeng, deputy director of the lasers and terahertz department at Wuhan National Laboratory for Optoelectronics (China). The talk given by Limpert is notable in that he discusses the coherent combination of a large number of ultrafast fiber amplifiers, with the goal of not only petawatt peak powers, but also megawatt average powers.

The LASE technical sessions are divided into five tracks: Laser Source Engineering, Nonlinear Optics,

complex-shaped parts that enable the development of lighter-weight cars and planes and better control combustion/ chemistry to reduce carbon emissions. Furthermore, with insight and technologies derived from BiOS research, 3D printing could create new capabilities for first responders and others in the field to quickly obtain the right piece of equipment.

“3D printing has a likeness to biology where material is grown, cell by cell,” says Helvajian. “In the most soaring of visions, a 3D manufactured product would not only have the necessary complex shape but also include means for ‘sensing’ an environment, harvesting energy, and ‘communicating’ its state. We are far from realizing this vision, but recent strides in fields such as in materials development and materials processing along with research that explores biological processes from the perspective of part

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PHOTONICS WEST PREVIEW c o n t i n u e d

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advertised Fresnel and spherical plastic lenses ranging from 3 mm to 3 ft in diameter (see Fig. 2). An ad from CVI Laser (Albuquerque, NM) offered optics of germanium, zinc selenide, potassium chloride, sodium chloride, and cadmium telluride for use with 10 µm lasers.

The April 1977 issue described diamond machining of metal mirrors, which the Lawrence Livermore National Laboratory used to make aspheric mirrors as large as 38 inches,

including the 11.8 inch axicon shown on the issue’s cover (see Fig. 3).

Optics in the 1980s

In an October 1984 review, Bob Shannon of the University of Arizona (Tucson, AZ) credited interferometric measurements with “the principle gains in productivity” in optics

FIGURE 1. The December 1974 cover of Laser Focus World

featured the new technology of adaptive optics, which had a mirror with an array of 21 piezoelectric transducers that shaped its flexible surface.

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OPTICS continued

manufacturing over the past 25 years. He wrote that aspheric optics were “beginning to enter the production stage.”

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The 1980s also saw a new approach to big optics—spin- casting parabolic glass telescope mirrors. Our June 1988 issue reported

acting precision, to make the Hubble

Space Telescope the world’s premier eye in the sky despite its flawed primary mirror, as I reported in the February 1995 issue.

Commercial optics advanced apace. In the January 1995 issue, II-VI Inc. (Saxonburg, PA) advertised two-axis diamond turning of precision aspheric lenses and metal mirrors. Newport Corp. (Irvine, CA) advertised mirrors providing the full optical bandwidth and time resolution needed for ultrafast titani- um-sapphire lasers. And AOtec, a subsidiary of the venerable American Optical Corp. (Southbridge, MA), advertised “glass quality from plastic lenses,” a departure from AO’s long focus on glass optics.

“The Year of WDM”

Strong demand for fiber-optic bandwidth offered by wave- length-division multiplexing (WDM) pumped up the market for narrowband filters. Herwig Kogelnik, director of Photonics Research at Bell Laboratories (Holmdel, NJ) proclaimed 1996 “the year of WDM” in our December 1996 issue. Multiplexing eight wavelengths sent 20 Gbits/s through a single fiber. In our March 1997 issue, the Optical Corporation of America (Marlborough, MA) described thermally stable WDM filters for the new 100 GHz (0.8 nm) dense-WDM channel spacing standard. After the turn of the century, DWDM systems became the backbone of the global telecommunications network.

In a series of other advances, metamaterials emerged from nowhere to become the cutting edge of 21st century optics, able to perform hitherto impossible feats, as described in our January

www.laserfocusworld.com Laser Focus World

2005 issue. A research paper concluded a metamaterial with negative refractive index could achieve subwavelength resolution, but only in the near field. CVI Optical Components and Assemblies advertised optics for 193 nm water-im- mersion photolithography, which provides subwavelength resolution for making semiconductor chips. The world’s fastest adaptive optics system was installed on the world’s oldest super-tele- scope—the 200-inch Hale Telescope at the Palomar Observatory (San Diego, CA). And the laser marketplace had become global, with advertisers including HC Photonics (HsinChu City, Taiwan), providing a variety of periodically poled nonlinear optical materials, and Kaleido Technology (Farum, Denmark), offering precision-molded aspheric glass optics.

October 2014 saw the award of the Nobel Prize in Chemistry to Eric Betzig, Stefan W. Hell, and William Moerner for developing super-resolution fluorescence

microscopy to overcome the limits of conventional optical microscopes. Special Optics (Wharton, NJ) said it was “excited to have made a small contribution” to Betzig’s work by developing custom microscope objectives for his experiments.

New materials for future optics

Looking forward, Duncan Moore of the University of Rochester says the future of optical components “is going to be all about broadband,” ranging from the ultraviolet to 14 µm for applications ranging from smartphones to military systems. Merely transmitting light is not enough; broadband optics should also be achromatic. “If you want a 10× zoom, you have some real challenges,” says Moore.

StingRay Optics (Keene, NH) has developed a series of SuperBand lenses optimized for wavelengths from 0.7 to 5 µm, which combine materials to bring the whole band into focus, says company president Chris Alexay. StingRay Optics

OPTICS continued

hopes to land a contract to develop a midinfrared zoom lens to handle both laser designation in the 1 µm band and imaging in the 3 to 5 µm band, avoiding the need for dual optical systems in drones.

The auto industry’s interest in 8 to 12 µm thermal imaging has dramatically reduced prices for optics and sensors in that band, says Moore. BMW offers the BMW Night Vision system as a $2300 option to help drivers spot pedestrians or large animals in or near the road. FLIR offers a thermal camera accessory for the iPhone at $349. But with market volume smaller in the mid-infrared, Moore says good 3 to 5 µm cameras still sell for tens of thousands of dollars.

“I can’t imagine a time when the industry has been more poised for new developments,” says Alexay. He expects the Naval Research Laboratory (Washington, DC) to report a promising new family of materials at the upcoming SPIE Defense Security and Sensing meeting on April

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standards. Thin-film coatings can provide that stability, and can be made on a micrometer scale for microscopic imaging. In 2014, DataColor (Lawrenceville, NJ) introduced a series of thin-film calibration color slides called ChromaCal.

Metamaterials and the future

The allure of metamaterials is their tremendous potential for building optical materials to order, with otherwise unobtainable properties. Optical metamaterials remain in the laboratory stage, but two invited talks at the December 2014 Materials Research Society (MRS) meeting in Boston gave exciting visions of the future.

In the first talk, Nader Enghata of the University of Pennsylvania (Philadelphia) said an impressive array of applications have already been demonstrated, including cloaking, superlenses, ultra-thin cavities, transformation optics, and metasurfaces. Then he went further. “Imagine a

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FIGURE 5. Metamaterial manipulates light waves for computation. (Courtesy of the University of Pennsylvania)

metamaterial that computes [see Fig 5]. Could we design a material to get a derivative or an integral of a wave that you put into it?” He has been exploring the possibilities of optical “metatronics,” metamaterials that conduct current and integrate optical and electronic functions, and his group is attempting to use one to take the second derivative of an input signal. In the long term, the group envisions an optical computational feedback loop.

In a second invited talk, Kevin

MacDonald of the University of Southampton (England) argued for moving beyond widely used metallic metamaterials. “We can do better with all dielectric opto-mechanical metamaterials; we want to avoid losses associated with metals and create much stronger optical forces between resonators,” he told the MRS meeting. He also envisioned moving beyond today’s static metamaterials to active metadevices, and perhaps ultimately to metastructures that could be reconfigured by changing the applied electromagnetic field.

How many of these bright visions are attainable in the next half-century? If the past is any lesson, we overrate some ideas and are surprised by some unexpected successes. But we can safely say that the future of optical components is not likely to be a sleepy backwater.

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e-mail to LFWFeedback@pennwell.com.

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red) to greater than 2300 nm and beyond, with electrical-to-optical efficiency reaching to more than 70% in some cases, notes Patterson.

The mounted bars can then be packaged into arrays that produce up to kilowatts of total output power, whether the output be a free-space laser beam or coupled into an optical fiber. With these sorts of capabilities, says Patterson, “any market from the traditional pumping of solid-state and fiber lasers, to direct-diode applications in medicine such as dermatology or phototherapy, to industrial processing of materials such as the deposition of laminates to emerging markets in cinematography and enhancements in advanced medical-imaging technologies may be addressed.”

Patterson notes that there have been many new developments over the past year: for example, enhancements in visible red and blue outputs for applications in cinematography and medical photodynamic therapy; fiber-cou- pled systems that output on the order of 10 kW in wavelengths ranging from around 800 nm to 1000 nm, typically used for all sorts of materials processing, including welding; and a unit developed to enhance magnetic-reso- nance imaging (MRI).

“All aspects of diode-laser technology were challenged here,” says Patterson. The challenges included development of the basic epitaxy design of the diode laser, advances in

the volume Bragg gratings that narrow the spectral line of the diode laser to a range that is useful for the particular application, custom package design that permits tunability of the spectral line emitted from the module, and the custom optics that form the beam to a precise output form also demanded by the application.

Patterson provides background on the MRI module (see Fig. 1), explaining that it permits the hyperpolarization of a particular isotope of xenon using a process called spin-exchange optical pumping; the spectrally narrowed and precise wavelength of circularly polarized laser light from the module excites rubidium electrons inside a gas cell. The use of hyperpolarized gas in MRI allows observation of otherwise inaccessible bodily processes, such as pulmonary function and blood profusion in the brain. The module itself emits 200 W of circularly polarized light at a 794.7 nm wavelength and a linewidth of <0.3 nm; the optically isolated beam is tolerant to 100% backreflection.

Direct diode

While laser-diode bars are used widely as laser pump sources, by using the right optical techniques, light from the same sorts of diodes can be directly coupled into optical fibers to produce a high-power “direct-diode” laser, notes Tracey Ryba, product manager for lasers at the TRUMPF Laser Technology Center (Plymouth, MI). For example, the same 940 nm diode-bar platform used by TRUMPF as pumps for its disk lasers is the source for the company’s kilowattslevel direct-diode systems.

Optical techniques for combining la- ser-diode outputs to boost power while maintaining brightness include spatial and spectral beam combining. However, the details, which are derived from careful optical design and which make all the difference in final beam brightness, are usually proprietary.

The diode bars in TRUMPF’s directdiode systems are mounted on a passively cooled heat sink, eliminating the

deposition, while the 50 mm-mrad applications typically are brazing, heat treating, and laser metal deposition.” Wavelengths in the “9xx” nm wavelength range are slightly shorter than those of traditional 1 µm lasers such as disk, fiber, and Nd:YAG. These shorter wavelengths allow better absorption in highly reflective materials such as copper, brass, and aluminum, says Ryba. Additionally, the lower-beam- quality versions are ideal for brazing and surface treatments due to the large divergence and the more distinct flattop mode profile, especially when compared to high-beam-quality disk and fiber lasers where a relatively complex beam delivery and large focal lengths are needed to achieve the same desired

effects at the workpiece.

Replacing traditional processes

The attributes of high-power laser diodes can lead to transformations in certain

areas of materials processing. “Major ‘direct-diode’ applications for these products are transforming the surface properties of large metal parts through heat treating—historically called case hardening—and cladding,” explains Frank Gaebler, director of marketing at Coherent (Santa Clara, CA).

Coherent manufactures laser diodes and laser-diode arrays over a broad range of output powers in configurations from single emitters through linear bars (fi- ber-coupled and free-space) up to 2D arrays of bars. The company’s most powerful system produces 10 kW of output power at 975 nm; internally, it consists of five bars, each derated to 2 kW to ensure tens of thousands of hours of main- tenance-free operation at or above specified power, says Gaebler.

The free-space output of the laser system can be configured to deliver a variety of interchangeable beam shapes (with widths from 1 to 12 mm and lengths from

6 to 36 mm) to enable rapid processing of large areas with a high degree of control over process parameters.

The product is targeted at large-area cladding applications to create a metallurgically bonded layer on the surface of a metal, usually some type of steel (see Fig. 3). “This is typically done in order to transform the surface properties—for improved wear characteristics or high corrosion resistance—without modifying the desirable bulk properties (such as tensile strength and rigidity) of the part,” says Gaebler. “Cladding is also often used to refurbish worn parts.”

Traditionally, large parts were mainly clad by thermal spray (for example, high-velocity oxygen-fuel spraying, or HVOF) or plasma-transfer arc (PTA) or, less commonly, electroplating, as Gaebler explains. Thermal spraying is a fast and relatively cheap process where metal powder is melted and sprayed on to the substrate, where it solidifies. The

In contrast, the laser-diode approach not only melts the powder, but also melts a very thin outer layer of the substrate, producing a fully bonded layer with very low porosity.

Giantree Laser Technology (Shanghai, China), one of the leaders in laser cladding applications in China, has extensive firsthand experience with laser cladding, thermal spray coating, machining/ grinding, and materials/alloys know-how, says Gaebler.

Giantree now has two in-house lasercladding systems based on high-power di- rect-diode lasers, including a 10 kW unit from Coherent. Giantree services clients in several heavy industries, such as petrochemicals and coal mining. Typical

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FIGURE 4. A VCSEL-based illuminator projects a pattern of spots that can be used to capture depth information in a 3D scene. An 8 W VCSEL array (inset) is only 1.5 mm square. (Courtesy of Princeton Optronics)

give very fast rise and fall times, typically <300 ps, and rise and fall times of <100 ps can be obtained with low-inductance submounts.

VCSEL arrays also have a narrow emission wavelength (<1 nm) and low variation of the wavelength peak with respect to temperature (0.07 nm/°C), which helps to reject the background illumination when the camera chip is attached with a narrowband filter.

Princeton Optronics’ technology has been developed with funding from the U.S. Defense Advanced Research Projects Agency (DARPA) and other agencies, says Ghosh. “We have developed VCSEL chips with power levels as high as a kilowatt from a 5 × 5 mm array with a greater than 55% wall-plug efficiency,” he notes. “This technology is being used to make many different types of products for 3D imaging applications.”

One such product is an 8 W VCSEL array used for time-of-flight as well as struc- tured-light applications. The laser chip is 1.5 × 1.5 mm in size, has a large number of VCSEL devices, and is mounted on a surface-mountable ceramic substrate. The device is finding application in computers, tablets, and mobile phones.

development of batteryoperated sensors for remote monitoring of water quality. LED-based instruments also allow

manufacturers to address market segments that might otherwise avoid their products because of footprint, cost, or complexity of operation.

Following are a few examples in which the use of UV LEDs versus traditional UV light sources is compared for various spectroscopic applications.

HPLC: Replacing deuterium lamps with LEDs

High-performance liquid chromatography (HPLC) is a separation technique in which a sample mixture is introduced into a column; the distinct compounds of the mixture then pass through the column at varied rates due to differences in how they partition between the mobile phase and the stationary phase. Once detected, these components are analyzed using a UV spectrophotometer. HPLC is typically

used for protein purification, routine process monitoring in pharmaceutical and beverage manufacturing, process quality control, and biotech research.

Current HPLC detectors typically use deuterium lamps as their primary light source due to their stable light output. This stability is characterized by measuring fluctuations in light output over short periods, such as the duration of a measurement. Using a UV light source with high light-output stability in HPLC ensures detection of lower concentrations of compounds. As seen in Figure 1, deuterium lamps are more stable than many UV lamp alternatives (for example, by almost two orders of magnitude over xenon flash lamps).

Engineers also prefer the long life of deuterium lamps, as well as the relatively high light output of the lamps at their HPLC-relevant UV wavelengths. Deuterium lamps, however, require a very stable power supply to maintain their performance and a warm-up period of up to 30 min to allow the lamp

to reach thermal equilibrium. For this reason, most lamps are left on while not in use so that the instru-

Table 1. Cost analysis for two typical fixed-wavelength HPLC detectors

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terium lamps. This allows end users to take complete advantage of the LED’s lifetime, typically 3000 to 8000 h, de-

analysis, the instrument using the LED is turned on only when needed.

pending on application conditions. In addition, UVC LEDs emit negligible front-side heat, which makes them ideal for heat sensitive samples.

With UVC LEDs, manufacturers can offer smaller, more cost-effective instruments for end users that require a single wavelength or a few fixed wavelengths. This evolution of low-cost, fixed-wave- length HPLC detectors will enable adoption in new applications such as caffeine detection in beverages and will increase penetration in applications such as prep HPLC of proteins.

Ozone monitoring: Improved measurement performance

Commonly found air pollutants, or “criteria pollutants,” include particulate matter, ground-level ozone, carbon monoxide, sulfur oxides, nitrogen oxides, and lead. Exposure to ozone, at even relatively low levels, is harmful to health and can result in reduced lung function and aggravation of pre-exist- ing respiratory conditions. Considering that ozone is also used in industrial applications in processes as varied as semiconductor cleaning to water purification, monitoring ozone levels is critical.

HPLC instrument cost analysis

Table 1 provides typical component and operating costs for a fixed-wave- length HPLC detector using deuterium lamps versus UVC LEDs. This illustrative example assumes detection for two fixed wavelengths and thus requires two UVC LEDs. Operating costs are estimated based on a typical laboratory operation where a deuterium lamp would be on 12 h a day, 52 weeks a year, and assumes 4 h of

Countries in Europe and Asia have even taken measures to limit auto traffic in cities or to shut down factories in order to curb emissions in densely populated areas.

The current EPA ozone standard is set at a level of 75 ppb; this quantification of ozone in air is measured using UV absorption spectroscopy. Ozone monitors traditionally use mercury lamps as the light source for their measurement, as ozone has a strong absorbance at ~254

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Tracking water quality with LEDs

Water purity is a major concern for developed and developing nations alike, with hydraulic fracturing (“fracking”) and possible effects of climate change highlighting water-quality concerns. The impact of natural events, such as rainfall and accompanying runoffs, and industrial water treatment are increasingly felt in water-distribution networks across the world. Rapid detection of changes in water quality is critical to ensure consumer health and environmental preservation.

Wastewater treatment plants and industrial facilities monitor influent and effluent water quality for productivity, effectiveness, and compliance with regulatory requirements. The collection of ongoing, real-time data on contaminant levels

Table 2. Cost analysis for two typical ozone monitors

* Energy cost of $0.12/kW-hr

**Four annual replacements for the mercury lamp at $25 each.

Table 3. Cost analysis of two water-quality monitors

*Energy cost of $0.12/kW-hr

**One replacement of the xenon flash lamp at $447 after typical life to 1E9 flashes.

www.laserfocusworld.com Laser Focus World

can decrease the response time to potential quality issues from days to hours. This depends on the use of autonomous water monitors—ones that need to be compact and cost effective—that continuously test water quality at multiple locations along the network.

Typical causes of changes in water quality include natural events, such as flooding, accidental discharge or spills, or other sources of contamination. UV photometry provides quantitative analysis of the organic content in water. By using continuous spectroscopic measurements instead of intermittent chemical testing with grab samples, end users gather process information, detect issues in water quality, and make the necessary process changes in real time.

Traditionally, these water-quality measurements have used xenon flash lamps as the light source for spectroscopy. Xenon flash lamps provide a broad spectrum of wavelengths and often require an expensive photodiode array for detection. These lamps also require an expensive power supply to maintain lamp performance. Although these high-quality instruments offer precise, accurate measurements of multiple parameters of water quality, they are often more than what a typical water facility requires. The associated costs are also restrictive to small water utilities, and unreasonable for developing regions.

Engineers can achieve the same benefits of xenon flash lamps for a subset of parameters by using UVC LEDs, along with a less costly detector and power supply. Newly available high-performance UVC LEDs offer linearity of measurement that matches the performance of expensive xenon flash lamps. This parameter refers to the correlation between the optical method of water-quality measurement with a reference method (typically a chemical measurement in the lab). A more compact, less costly instrument can thus become accessible to a wider crosssection of the market. Additionally, the reduced size and low power consumption of these instruments open possibilities for remote monitoring.

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radiation hardened cameras. With superior capabilities for operating in radiation

environments, they provide excellent image quality well beyond dose limitations

of conventional cameras. MegaRAD cameras provide excellent signal-to-noise

and sensitivity with wide spectral response, making the MegaRAD series of

cameras well suited for radiation hardened imaging applications

see what you’ve been missing

• Learn more at thermoscientifc.com/cidtec

MegaRAD3 cameras produce color or monochrome video up to

3 x 106 rads total dose

MegaRAD1 cameras produce monochrome video up to

1 x 106 rads total dose

KiloRAD PTZ radiation resistant camera with integrated

Pan/Tilt/Zoom