Lighting Electronics: July 2015

July July2014 2015

Latest Lighting

TRENDS

A Look at the Latest Developments in the Intelligent Lighting Revolution

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Top 10 Display Technologies Customizable LED Tuning

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CONTENTS

Lighting Electronics

EDITORIAL STAFF Content Editor Alex Maddalena amaddalena@aspencore.com Digital Content Manager Heather Hamilton hhamilton@aspencore.com Tel | 208-639-6485 Global Creative Director Nicolas Perner nperner@aspencore.com Graphic Designer Carol Smiley csmiley@aspencore.com

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TECH TRENDS Top 10 Trends in Display Technology TECH REPORT

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The Role of Tunable Lighting in the LED Revolution

EEWEB FEATURE The Bright Future of Intelligent LEDs

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Lighting Electronics

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TECH TRENDS

10

Top Trends

in Display Technology

By Sri Peruvemba Society for Information Display

The global display industry continues to grow, with new technologies enabling a host of emerging products and applications. To help you keep track of what’s happening and what to keep an eye on in the world of displays, here is a list of the current top 10 trends in display technology.

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Lighting Electronics

WEARABLES

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The most high-profile recent entry to the burgeoning wearable market, smart watches will continue to be a hot topic, as more and more companies are beginning to release their own version of this doit-all timepiece. But wearables comprise more than watches, fitness bands, and, yes, smart glass. Wearable displays for virtual and augmented reality (VR, AR) experiences are on the cusp of being truly ready for broad market availability.

All of these applications have to convey large amounts of information on small displays, which must deliver high brightness and resolution with very low power consumption. Thus, organic LED (OLED) and ePaper displays are gaining market share because they’re thinner and lighter, with better color performance; for this category, in particular, flexible OLEDs have a bright future.

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CURVED SCREENS

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Representing another area of greatly heightened public interest over the past year or so, curved screens have three primary applications: • TVs – With more of the screen directed toward the focal point, where the viewer tends to sit, curved screens create a better and more satisfying viewing experience.

• Smartphones – Curved screens not only make the phone more aesthetically pleasing, but they also create new opportunities for viewing information visible on the curved edge or side of the screen.

• Dashboards – Beautiful curved displays inserted into car dashboards will be highly functional and greatly improve driver usability, eliminating the cluster of jarring right angles that create limitations for previous incarnations of rectangular displays.

TECH TRENDS

QUANTUM DOTS

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According to market research firm IDTechEx, “Quantum dot-enhanced LCD panels are set to capture a 14-percent share of the TV market by 2020.” Quantum dots (QDs) are light-emitting semiconductor nanocrystals that can convert light from one wavelength to other specific wavelengths, creating intense red, green and blue colors.

The dots can support large LCDs, making them good candidates for TV screens and other applications. Backlit QD-LCDs are garnering interest and investment because they greatly improve image quality while costing less than OLED, as the LCD fabs are already in place, many of them fully depreciated. Pioneering companies in this space include Nanosys, which embeds quantum dots into sheets, Quantum Materials, which prints the dots on film, and QD Vision, whose technology routes light from blue LEDs through tubes filled with red and green quantum dots to create pure white light.

Heavy-metal-free quantum dots tuned between ultraviolet and infared on the elecgtromagnetic spectrum. Courtesy of Nanoco Industries Ltd.

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MORE PIXELS/ ENHANCED READABILITY Large-screen TVs with UHD/4K technology are starting to hit the market in greater numbers, to cater to buyers’ interest and desire for a range of price points. In addition, there is beginning to be a push for video of the same high quality to be viewable on tablets, wearables and other smaller screens. This will require smaller displays that can accommodate very high-quality content, creating opportunities for companies that can find ways to cram in more pixels per unit of real estate.

In the industrial and specialty display markets, there is great interest in 8K pixel resolution.

Concurrently, enhanced readability will become an important trend. A number of disparate professions have been using very high-resolution displays for some time, e.g., air traffic control (ATC) and digital x-rays. While both are literally life-or-death applications, their requirements for readability are very different. In the medical space, where the surgeon needs at-a-glance readability of the patient’s information, the display is regularly scanned for pixel defects to ensure all are working perfectly, as many of these displays are monochrome. For ATC, the requirement is large displays with high resolution – the controllers need to be able to see everything easily and study it carefully to make informed decisions. Mainstream applications are now also requiring better displays with higher resolution at both ends of the pixel spectrum, which will benefit these more niche users, as manufacturing efficiencies will deliver even better products at a lower cost.

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Lighting Electronics

BETTER IMAGE QUALITY

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Not everyone thinks more pixels are the only way to enhance the user experience.

For example, Pixelworks offers chipsets and algorithms designed to optimize the quality of any display. The technology is predicated on the fact that, due to increased pixel density, the human eye cannot distinguish individual pixels.

This means that images are more lifelike than ever and that any artifact can intrude on the viewing experience.

Dolby’s HDR (High Dynamic Range) technologies also deliver greater luminosity, along with better contrast and more saturated colors.

Photo courtesy NASA

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IMMERSIVE VIRTUAL REALITY

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Why can’t computing feel completely natural? Magic Leap, a company in the VR field, has posed this question, and rather than taking away from the human experience, immersive VR is meant to be a blend between the digital and real world.

Magic Leap’s approach, is a biometric platform for experiencing the digital world that respects how humans naturally function. Oculus (now part of Facebook) is another company that has been working on immersive VR, most famously for its Oculus Rift product that creates a stereoscopic 3D view and has ultra-low-latency 360-degree head tracking – factoring real-life head and eye movement into how users interact with the technology.

TECH TRENDS

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FLEXIBLE, FOLDABLE/ ROLLABLE DISPLAYS

IDTechEx foresees the market for plastic and flexible AMOLED displays will reach $16 billion by 2020. We’ve already begun to see clothing with embedded displays come to market, as technology has been developed to adapt itself to the rigors of fabric wear and maintenance.

The eventual goal is to enable users to fold down or roll up virtually any mobile device and put it in a pocket. This creates a huge opportunity, as mentioned earlier, for flexible OLEDs. Samsung and LG Display are creating flexible OLEDs that are literally changing the shape and capabilities of their latest smartphone offerings. Companies like E Ink and Polyera are constructing flexible ePaper displays that are aimed at wearable devices. Glass is still the most popular substrate for displays, but – as noted above—plastic is starting to gain ground.

SECONDARY DISPLAYS

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An interesting emerging trend is to have a secondary display on mobile phones.

While we tend to focus our attention on a phone’s primary display, there is a great deal of unused real estate on the back of a phone. This space is starting to be utilized for some innovative new always-on secondary displays based on low-power display technologies, which allow the user to access information on the phone’s existing footprint without draining the battery.

Some unique solutions currently coming to market include YotaPhone, an Android phone with full-touch capacitive screens on the front (AMOLED) and back, both utilizing Corning Gorilla glass; popSLATE, an iPhone 6 cover that converts the back of the phone into a shatterproof e-paper screen with push button slideshow mode; and the Tegware Bagel, an iPhone 6 case with an integrated e-writer that enables using the included stylus to jot notes or sketches right on the phone.

The latter offering also falls into our next trend area—displays for writing.

Kyocera flexible phone bracelet

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Lighting Electronics

DISPLAYS FOR WRITING

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While many of us run our lives using our smartphones, we still tend to turn to pen and paper for taking notes, writing reminders to ourselves, doodling ideas, etc.—it just comes naturally. The next time you are in a meeting, notice how many people brought paper notebooks and pens. Studies have shown that we tend to retain information better when we have used the connection from brain to hand to write it down than when we simply enter, or scan, it into our phones.

Displays for writing are thus making a comeback. Many tablets now have a pen input feature, and for smartphones, some new options are being developed, such as the previously mentioned Tegware Bagel.

Samsung’s Galaxy Note incorporates pen writing ability and is quite popular. This category also creates new opportunities for plastic displays since plastic tends to win out over glass for e-writing preference. Kent Displays manufactures the Boogie Board line of eWriters, which are available in a variety of sizes and styles. If you’re given to copious note taking, the argument for such a solution is compelling: Kent Displays claims one 8.5 LCD eWriter can save over 50,000 sheets of paper. This would also allow schools to save on resources while still teaching students handwriting (another strong argument in its favor).

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HAPTICENABLED DISPLAYS

Haptic technology is tactile-feedback technology that recreates the sense of touch by applying force, vibration or motion to the user. This feature enhances the keyboard typing experience on a display and creates a more immersive experience in gaming applications.

Companies that are already bringing haptic displays to market include Immersion, whose haptic solutions are being used in mobile, gaming, automotive, medical and consumer products, and Novasentis, which is focused on integrating its electromechanical polymer (EMP) actuator technology into wearable devices.

As you may have noticed, what’s exciting about many of these trends is not just how they’ll be used, but how they work—it’s the ingredients that make these emerging technologies viable and marketable.

TECH TRENDS

MYLINK

Lighting Electronics

The Role of

Tunable LIGHTING

in the LED Revolution

By David L. Bay, LC OSRAM SYLVANIA

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TECH REPORT

In concert with the solid-state lighting revolution, the world of commercial lighting is steadily transforming from systems with static output to highly flexible and versatile systems. These new control capabilities offer dramatic new opportunities in how lighting is designed and used, with significant benefits to owners of commercial buildings. In particular, solid-state lighting offers the largely novel capability to tune color output, which will play a significant part in the LED revolution.

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Lighting Electronics

T

he large majority of traditional commercial lighting systems, including fluorescent and highintensity discharge (HID), are operated with a static light output. Control is largely limited to On/Off. Although dimming of fluorescent and HID is available, light output instabilities can become problematic during deep dimming. In fluorescent lamps, the color of the produced light is largely determined by an internal phosphor coating; therefore, control of a fluorescent lamp’s output color characteristics is not practical.

Varying lighting’s CCT and CRI can dramatically impact how a space, its contents and its occupants appear and/or are perceived.

While these traditional sources may be On/Off switched, occupancy sensor applications having frequent On/Off switching can reduce fluorescent lamp life, with the most extreme effect seen in lamps operated by popularly used instantstart electronic ballasts. Switching of HID is even more problematic, as the lamp requires a relatively long Off-time for restrike as well as a warm-up period to achieve full brightness once turned Off. Although controlling the color of light produced by traditional light sources has not been practical, this has not stopped end users from seeking it. In lighting design, lighting’s color is typically characterized by two metrics. The first is correlated color temperature (CCT), which expresses the shade of white light as compared to a body that is thermally heated to a temperature (in degrees Kelvin) ranging from a low/warm (<3000K) to

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neutral (around 3500K) to a high/cool (>4000K). The other is the color rendering index (CRI), which expresses how closely a light source renders colors as compared to an ideal or natural light source (e.g. the sun). Varying lighting’s CCT and CRI can dramatically impact how a space, its contents and its occupants appear and/or are perceived. Additionally, one’s mood and emotion can be impacted by the lighting’s color characteristics.

Color output can be controlled to a small extent with fluorescent lamps, but the solutions are limited in flexibility and can impose a significant cost. To change the shade of white (e.g., from a warm 3000K to a cool 4000K), the owner would have to change the lamp, add a color filter to the luminaire, or separately control arrays of warm and cool CCT lamps.

The advent of solid-state lighting, notably light-emitting diodes (LEDs), offers significant control possibilities, including color. The LED can be frequently switched with no penalty to service life. Many LED luminaires are available with 0-10V dimming as a standard driver feature. A well-designed LED driver and controls can deliver smooth, continuous dimming across a wide range, though good practice still requires assurance of compatibility/ proper selection of LEDs, driver and control components to ensure stable operation (i.e., no flicker). Because dimming reduces LED junction temperature, it can increase LED service life.

TECH REPORT Additionally, because LEDs are digital devices, they are inherently compatible with intelligent lighting controls.

Such controls offer the opportunity to design lighting systems in which each luminaire in an installation is individually addressable, programmable and/or able to be networked/connected. Additionally, individual and/or arrays of LEDs can be separately controlled, thereby enabling luminaires to have variable light output distributions without moving parts.

Via a computer, computer tablet or smartphone device, such a lighting solution enables the user to select desired lighting schemes at will for a given space. Further, with appropriate LEDs, the color of the luminaire’s light output could be adjusted/controlled.

tuning; imitate the warm color of incandescent lamps while being dimmed; and/or offer precise color matching between LED products as well as control capabilities for maintaining constant color output throughout their life.

These are important capabilities because, as stated earlier, the color of lighting can dramatically affect the appearance of spaces, people and objects. In a retail environment, for example, color output is critical to make products (e.g., clothing, vehicles, produce, etc.) appear vibrant and appealing. In a healthcare facility, color output, such as imitating the warm lighting associated with home,

In a retail environment, color output could be precisely tuned to optimize presentation of each individual merchandise display.

Control of LED lighting’s color is achieved by combining separately dimmable arrays of warm and cool CCT LEDs; by color mixing arrays of red, green, blue and amber LEDs; or by adding separately dimmable colored LEDs to white (phosphor-converted) LEDs. These arrays are in turn controlled by a master controller using a DMX, DALI or other interface. Depending upon the choice of LED configurations, a broad range of CCT and CRI, from saturated reds, blues, greens and yellows to a broad range of “whites” which have a wide range of CCT and/or CRI, can be realized. Various general lighting products are now available that provide manual and/or programmable color

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Lighting Electronics

adjust color to view themselves under different lighting conditions.

can reduce patient stress; it can also be important for health professionals to detect illness (e.g., jaundice). In an office, color can promote social interaction by rendering faces more naturally.

In spaces that don’t receive daylight, the lighting could automatically change throughout the day to match the actual or an idealized daylight cycle.

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The ability to manually or automatically adjust light color opens the door to numerous design possibilities.

Immediate applications are those in which required lighting color changes based on space function or time.

In a retail environment, color output could be precisely tuned to optimize presentation of each individual merchandise display. This color could then be manually adjusted as displays change or automatically adjusted based on time of day or fashion season. In changing/dressing rooms, shoppers could be given the ability to manually

In an office, the color output of the ambient lighting could automatically adjust to blend with daylight. In spaces that don’t receive daylight, the lighting could automatically change throughout the day to match the actual or an idealized daylight cycle. The owner could be given the ability to adjust color quality to adapt meeting spaces to different functions.

In a hospitality space, the designer could precisely tune color quality to match the space décor after final materials and furnishings are installed. The lighting could be re-tuned should new furnishings be installed in the future.

In a restaurant, color output could be adjusted based on time of day—e.g., cool during business luncheons and warm during evening dining.

Another intriguing possibility of adjusting light source color emission is the growing understanding and interest in the link between lighting and health. The human eye contains various photoreceptors, some of which are primarily used as an input to the brain’s master clock that regulates

TECH REPORT

Intelligent lighting controls offer the opportunity to design lighting systems in which each luminaire in an installation is individually addressable, programmable and/or able to be networked/connected.

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Lighting Electronics

the body’s circadian system. Circadian response is based on intensity, color spectrum, timing and duration of light exposure. While intensity (vertical light level) is believed to be an important input, circadian regulation is known to be responsive to short-wavelength (“blue”) light. This has stimulated interest in color tunability capable of delivering high CCT (5000+K) lighting. As this design trend develops, we are likely to see further demand for color-tunable lighting, including healthcare applications such as assisted living facilities.

LEDs afford the lighting designer a new control option, CRI modulation, which can be used to reduce lighting energy costs in applications where intensity dimming is not desired or practical.

Consider a public interior meeting space that is intermittently occupied. During times of no occupancy (based on input from occupancy sensors installed in various lighting zones throughout the space), CRI would be reduced while maintaining light level and CCT. If the space becomes occupied, CRI would automatically increase to the design level, but only in the immediately occupied areas. Lighting outside the occupied zone would continue to be illuminated with a lower CRI. In one tested application, this approach was generally accepted by occupants while generating 23 percent energy savings. CRI modulation therefore

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provides an alternative to intensity dimming as a means to save energy.

Color-tunable lighting adds a new dimension of control for commercial building general lighting applications. It allows precise matching of color quality to the application. It extends the function of the lighting system by enabling it to flexibly adapt illumination color according to a space’s décor, presentation and current visual needs. It can play an important role in circadian lighting. And it provides an energy-saving alternative to intensity dimming in certain applications.

Based on this utility, color tuning will become increasingly common in commercial buildings as the LED revolution continues to change the world of lighting.

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Lighting Electronics

The Bright Future of Intelligent

LEDs

By Rick Freeman, GE Lighting

Light that can listen, learn, and see?

Thatâ&#x20AC;&#x2122;s a reality in the next era of lighting innovation in a world where lighting will truly change the way we live, work, and play.

From intelligent cities to intelligent buildings to connected homesâ&#x20AC;&#x201D; light is connecting to data to unleash a whole new world of possibilities for how we utilize lighting.

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EEWeb FEATURE

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Lighting Electronics

L

ight has remained essentially the same for a century, one might say.

So what changed? The answer is two-fold: Better light-emitting diodes and lower-cost sensors, wireless transmitters and microprocessors.

LED technology has made major strides in recent years. Early products struggled to produce a quality light or simply enough of it. Today, however, the quality and light output of LED lamps and fixtures is comparable, if not superior to, traditional sources.

The result is rapidly increasing adoption, particularly in the commercial sector where LED installations and retrofits are taking place in supermarkets and department stores, banks, office buildings, hotels, restaurants, arenas, warehouses and many other types of facilities. In fact, according to a report by global management consulting firm McKinsey & Company, LED usage will reach about 70 percent in commercial environments by 2020, up dramatically from just between 10 to 20 percent today.

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At the same time, advances in electronics and manufacturing have ushered in a new generation of much smaller, more powerful, less expensive wireless sensors, transmitters, and processors that easily integrate with LED lights, which operate as semiconductors, where illumination is achieved by movement of electrons through a semiconductor material, opposed to sending an electrical discharge through an ionized gas.

It all has the industry excited, and rightly so. This convergence of intelligence and infrastructure has far-ranging implications and the potential to create realities limited only by imagination.

Intelligent Cities Parking downtown is a pain, but not in the intelligent city of the future.

Networked LED street lightsâ&#x20AC;&#x201D; the neurological system of the interconnected metropolisâ&#x20AC;&#x201D;will have the ability to direct drivers to available spaces with the help of built-in image sensors and wireless transceivers.

EEWeb FEATURE

From parking and traffic to temperatures, humidity, precipitation, ozone levels and pollution, streetlights are positioned to be the key real estate that indicates how certain attributes of a city are performing.

The same streetlight in San Francisco could serve as a seismic sensor and act as an indicator beacon in the event of an earthquake. Warnings or instructions could be carried across a public-address speaker concealed within the light post, as well. A push-to-talk system, meanwhile, could prove invaluable in an emergency response situation.

These features may be aspirational but demonstrate how, sooner rather than later, LED streetlights will be a critical part of high-performing networks that give cities a realtime view of what’s going on.

In fact, some are already discovering what’s possible, including the city of San Diego, which is now using wireless microprocessors to move toward a metered (rather than flat-rate) tariff for its streetlight energy usage with its local utility company. The technology provides accurate energy metering (specific usage information) of San Diego’s LED streetlights, allowing the city to pay only for what it uses.

Presently, LED penetration in roadway lighting is less than 10 percent across the U.S., but that’s about to change, says

the U.S. Department of Energy (DOE).

In its latest energy savings forecast, the DOE predicts that 83-percent of street/roadway lighting will be LED by 2020, with almost 100-percent being LED by 2030. From parking and traffic to temperatures, humidity, precipitation, ozone levels and pollution, streetlights are positioned to be the key real estate that indicates how certain attributes of a city are performing.

The bottom line is that cities are beginning to understand that intelligent street lighting can make a big difference—saving money, making money, enhancing citizen satisfaction and, ultimately, leaving a lasting impact.

San Diego is using lighting intelligence to pay a metered rate for the electricity its LED street lamps use.

Intelligent Buildings Facilities such as offices and high-rises can also capitalize on the digital nature of LED to connect lights and sensors to each other and to a building’s IT network.

The result can be a rich array of locationspecific data on room occupancy, amount of daylight, temperature, humidity and other variables. Using this data, the technology mediates environmental, user and building information to both save energy and maintain occupant comfort.

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Lighting Electronics

As with sensors and transmitters, lighting processors are becoming more sophisticated and less costly, and widespread commercial adoption remains only a matter of time. In fact, Title 24 of the California Energy Commission’s efficiency standards mandates the use of lighting processors in some new buildings. Enacted in 2013, it is among the first pieces of legislation of its kind, and, undoubtedly, an indication of things to come.

Integrated microprocessors—where lighting control is interfaced with a building automation system (BAS) to simultaneously manage heating, ventilation and cooling (HVAC)—have the greatest potential to elevate operations to new levels of efficiency and effectiveness. For instance, an intelligent office might want to automatically dim lights on a sunny day to limit wasteful energy use or turn down the heat in a crowded conference room to keep occupants comfortable.

Light is even changing the way we experience retail stores. Indoor location

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For instance, an intelligent office might want to automatically dim lights on a sunny day to limit wasteful energy use or turn down the heat in a crowded conference room to keep occupants comfortable.

technology—a form of Visible Light Communication (VLC)—is making it possible for lights to “talk” to shoppers by leveraging LED modulation (the “pulse pattern” produced by an LED light source, which is unique, like a fingerprint).

This pattern, while imperceptible to the human eye, can be detected by the cameras on smartphones and tablets, meaning LED fixtures with embedded sensors can pinpoint a customer’s exact location in a store—provided that customer opts in and is currently using the retailer’s app on a mobile device.

EEWeb FEATURE For store owners, this creates a tremendous opportunity to deliver new value to consumers, from personalized shopping lists and easy-to-follow maps to product info and special offers or coupons based on where a person is standing in a particular aisle, relative to specific goods or merchandise.

And not a moment too soon, many say.

To better understand the impact of smartphones and online information on in-store shopping, Google recently partnered with Ipsos MediaCT and Sterling Brands for an online survey.

The study revealed that consumers want more information and customized experiences during their shopping journey: Two in three shoppers who tried to find information within a store say they didn’t find what they needed, and 43 percent of them left frustrated.

Meanwhile 71 percent of shoppers who use smartphones for online research say their device has become more important to their in-store experience as well.

Beyond the retail industry, lighting-based indoor positioning systems also could see application in airports, hotels, hospitals and many other environments where it is beneficial to know one’s exact location.

Intelligent Homes Affordable, connected solutions are even making it possible for people to manage the lighting in their homes from anywhere in the world. Intelligent LED bulbs that can be controlled via smartphone are now available for as little as $15. These fit standard sockets and connect to a central hub in the house

($30-$60 extra), allowing individual or group control of dimming and scheduling (automating lights to turn on when you wake up, turn off when you leave or dim when bedtime approaches).

In time, bulbs could even be “taught” to respond to an individual’s presence or a change in light level thanks to learning algorithms that record and recall personal preferences. The fact is lighting is just one aspect of the future connected home, where appliances such as washers, dryers, ranges and refrigerators all function from a single, unified hub. It’s all further proof of technology’s power to bring us together—minds and machines.

Light has changed little over a century, but thanks to smaller sensors, smarter processors—and big imaginations—the years ahead promise an unprecedented shift in the role lighting plays in our lives. We won’t know it at first, but when parking’s a cinch and shopping’s done in a snap, and we return to our warmly lit homes, then we’ll feel light’s touch all around us, comforting us and connecting us in all new ways.

Wash the dishes, start the dryer and dim the lights all from the comfort of your couch?

Well, why not!

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M o v i n g To w a r d s a

David Elien VP of Marketing & Business Development, Cree, Inc.

Clean Energy

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