EEWeb Lighting Electronics - April, 2014

APR 2014

PHILIPS HAS THE LEDS TO

THE FUTURE OF FARMINGFROM PLANT FACTORIES TO URBAN FARMS,

Capacitive Sensing LEDs New Luxeon Lime LEDs

LIGHT THE WAY

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READY TO LAUNCH

For the launch of the Tiva C Series Connected LaunchPad, TI has partnered with Exosite, mentioned briefly above, to provide easy access to the LaunchPad from the Internet. The LaunchPad takes about 10 minutes to set up and you can immediately interact with it across the Internet and do things like turn an LED on and off remotely from the website and see the reported temperature as well. It can also display approximate geographic location based on the assigned IP address and display a map of all other connected LaunchPad owners if they are active and plugged-in to Exosite. “In addition, it supports a basic game by enabling someone to interface to the Connected LaunchPad through a serial port from a terminal while someone else is playing with them through their browser. It is basically showing how you can interact remotely with this product and a user even if you are across the globe,” Folkens explained.

START DEVELOPING

The Tiva C Series Connected LaunchPad is shipping now and the price is right; at $19.99 USD, it is less than half the price of other Ethernet-ready kits. The LaunchPad comes complete with quick start and user guides, and ample online support to ensure developers of all backgrounds are well equipped to begin creating cloud-based applications. “We have assembled an online support team to monitor the Engineering-to-Engineering (or E2E) Community,” Folkens said. “Along with this, you also got a free Code Composer Studio Integrated Development Environment, which allows developers to use the full capability. We also support other tool chains like Keil, IAR and Mentor Embedded.

Affordable, versatile, and easy to use, the Tiva Series Connected LaunchPad is well suited for a broad audience and promises to facilitate the expansion of ingenious IoT applications in the cloud. As Folkens concluded, “The target audiences actually are the hobbyists, students and professional engineers. A better way of looking at it is that we are targeting people with innovative ideas and trying to help them get those ideas launched into the cloud.”

Lighting Electronics CONTENTS

3

Intel Galileo Board for Smart

Lighting Applications

The Intel Galileo board is the first ever development board to be available from the Arduino Certified program. This open-source electronics prototyping platform allows for engineers and hobbyists alike to develop new and exciting applications. One of the most talked-about smart device applications is smart lighting. Smart lighting enables multiple manual and programmatic light control methods in addition to or replacement of the traditional light switch. This can be used to improve the customer experience and reduce costs by ensuring lights are on only when they need to be. The Galileo board’s flexibility and diversity allows for it to be a prime development platform for these smart lighting applications.

Overview of the

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A warehouse aglow with LEDs may well sound like a vision of the future, but for Philips Lighting, it exemplifies the future of farming. In the face of a

surging world population and dwindling natural resources, indoor farming is increasingly playing a bigger role in feeding urban populations. While energy demands have been consistent barriers to this burgeoning industry, the rise of new energy-efficient lighting solutions, such as Philips’ Horticulture Light Emitting Diodes (LEDs), promise to circumvent these challenges and shape the next generation of indoor farms. EEWeb spoke with Erik Jansen of Philips Lighting, about how these new LEDs will enable the farming of the future.

THE FUTURE OF FARMING

Philips’ Horticulture LEDs provide optimal conditions for indoor plant growth

Sensor Status Driven LED ControlsTo improve visual feedback to the users or to imitate mechanical switches, LEDs can be controlled in various ways in firmware. Some common methods are:

GPO0

LED ON Time

CS0

Figure 2. LED ON Time

CS0GPO0

Figure 1. LED Toggle

LED EFFECTSEffective user interface designs include some type of feedback to the user when they have capacitive touch buttons. Mechanical buttons inherently provide tactile feedback to users when the user presses the mechanical button. On the other hand, capacitive buttons do not provide any tactile feedback. Hence, UIs with capacitive touch buttons utilize various forms of feedback, including visual, audio, and haptic (tactile). Depending on the user interface design, multiple types of feedback can be used in combination. Among these feedback types, using LEDs for visual feedback is a very common approach. In this section, we’ll see various types of LED effects and some of their use cases.

LED On/OffThis is the simplest type of LED effect, often used to indicate the touch status. The LED is positioned at the back of the sensor pad and acts as a backlight. The LED lights up, illuminating the button when it is touched, and the LED goes off when the touch is released. An example would be the menu or back button in an android mobile such as the Samsung Galaxy S4.

BlinkingOften TV manufacturers supply a standard remote control for different models. Some of the keys in the remote are not applicable to some models. In that case, the backlight can be blinked upon touch to indicate that the key is invalid. This is done by periodically switching the LED on and off.

ToggleConsider a mechanical switch controlling your room light. When the switch is pressed once, the light is ON and the light continues to be ON as long as the switch is in that same state. When the switch is pressed again, the light turns off. The toggle feature is similar to the mechanical toggle switch. When a capacitive button is touched, the corresponding LED lights up. The LED continues to be ON even if the user removes the finger from the button. The LED goes OFF only when the button is touched again. So, the output toggles its states upon every rising edge of the capacitive senor state (OFF to ON) which is shown in the figure below. CS0 indicates the sensor state and GPO0 indicates the LED state.

LED On timeGenerally for capacitive buttons, the LEDs are right beneath the buttons, thus emitting light at the center. The LED is hidden when the user places the finger on the button. In such cases, it might be difficult for the user to realize that the LED was ON if the LED is turned off immediately upon releasing the touch. Instead the LED can be kept ON for a short period after the touch is released, thus providing better visual feedback to the user. This feature is called “LED ON time”. Figure 2 depicts this feature.

“UIS WITH CAPACITIVE TOUCH BUTTONS UTILIZE VARIOUS FORMS OF FEEDBACK, INCLUDING VISUAL, AUDIO, AND HAPTIC (TACTILE).”

“Lime is truly a revolutionary product for the whole LED market,” Cosenza explained. “It will not only enable a broader color palette for mixing, but has benefits for general white illumination as well .” While lime green isn’t typically the most common color for LED lights, it can be mixed and matched with other hues to create high quality white light. Not only does Lime enable recipes for white light with high CRI and high R9 , but also enables extremely high system-level efficiency—an important factor for mass industry adoption.

THE ROAD TO LIMEAt the products’ inception years ago, the idea was to make the most efficient LED possible. “We tried to get the brightest possible light while simultaneously using the least amount of power possible, without any boundaries for color or CRI” Cosenza recalls.

The Philips team installed some of their high efficiency LEDs in the streetlights of an urban neighborhood. It was not until the residents of that neighborhood started complaining about the “ghoulish” green hue the lights

emitted did the team realize it was time to make the LEDs less clinical

and more natural.

The results are the LUXEON Rebel ES and Z Lime family of LEDs, with easy blending capabilities for a natural, powerful, and efficient white LED light. The LUXEON Rebel ES Lime is a 2-millimeter, domed emitter that is reaching the 200 lumens per watt area while providing stunningly saturated color in that previously unattainable area between green and yellow. The undomed micro package of LUXEON Z enables close packing density of Lime and other colors for more homogenous color mixing.

“The LUXEON Rebel ES Lime is a 2-millimeter, domed emitter that is reaching the 200 lumens per watt area while providing stunningly saturated color in that previously unattainable area between green and yellow.”

“While lime green isn’t typically the most common color for LED lights, it can be mixed and matched with other hues to create high quality white light.”

Philips Lumileds has been continually impressed with how far-reaching the applications for their Lime-enabled LEDs have been. “We are quickly seeing things including a new generation of high-end stage and studio lighting where users need high quality light and the ability to tune the colors,” Cosenza explains. The applications also span to the home, where users have been making simple spotlight retrofits using the LUXEON Z family LEDs for color tunable lighting. With the lighting market racing to generate the next industry leading

innovation, Lime-enabled applications are certainly finding their place at the head of the pack. “There’s quite a bit of momentum now,” Cosenza says. “We don’t think we’ve it used to its full potential yet, there are definitely new opportunities to discover.”

PRODUCT OVERVIEWIntel Galileo Development Boardfor Smart Lighting Applications

TECH ARTICLECombining Capacitive Sensingand LED Lighting

COVER STORYThe Future of Farming:A Look at Philips’ Horticulture LEDs

FEATURED ARTICLEPhilips LUXEON Lime LED:Where No LED Has Gone Before

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Lighting Electronics




Overview of the

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TECH ARTICLE

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Overview of the

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Board Hardware Applications

The Intel Galileo board can be integrated with various modules to enable the controls for your smart lighting

application. Using a relay, a light sensor, and a pushbutton, the Galileo board can be transformed into a fully functioning smart lighting controller. The relay controls the power to the LED light bar, the light sensor acts as a motion sensor, and the pushbutton as a switch. The Galileo’s Ethernet connects this to your network for remote management. This enables unique lighting applications such as motion light detecting, dimming control for lower power consumption, and remote light triggering.

Demo

Ethernet

Support for Arduino Shields and Arduino IDE

To watch a video overview and demonstration of the Intel Galileo Board, click the image below:

Intel Quark Processor

UART USB

JTAG

Micro SD Slot

7

TECH ARTICLE

777

Board Hardware Applications

The Intel Galileo board can be integrated with various modules to enable the controls for your smart lighting

application. Using a relay, a light sensor, and a pushbutton, the Galileo board can be transformed into a fully functioning smart lighting controller. The relay controls the power to the LED light bar, the light sensor acts as a motion sensor, and the pushbutton as a switch. The Galileo’s Ethernet connects this to your network for remote management. This enables unique lighting applications such as motion light detecting, dimming control for lower power consumption, and remote light triggering.

Demo

Ethernet

Support for Arduino Shields and Arduino IDE

To watch a video overview and demonstration of the Intel Galileo Board, click the image below:

Intel Quark Processor

UART USB

JTAG

Micro SD Slot

http://www.eeweb.com/company-blog/mouser/galileo-board-smart-lighting-controller/

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CAPACITIVE SENSING

By Vairamuthu Ramasamy and Shruti Hanumanthaiah

Some applications require more visual effects apart from simply turning on and off an LED. For example, a laptop may blink the power LED with its brightness gradually increasing and then gradually decreasing when the device is in stand-by. This is called the breathing effect. This is one of the many LED effects such as fading and blinking used in devices. These advanced LED effects, when combined with capacitive touch buttons, improve the aesthetics and the user experience of the system.

It’s often desirable to implement multiple features using a single System-on-Chip (SoC) to reduce the BOM. In this four-part series, we’ll discuss the different aspects of implementing capacitive sensing and LED lighting using a single SoC, including the following topics.

We will briefly describe different LED lighting techniques adopted in capacitive sensing-based UI applications using real-world use cases.

Pulse Width Modulation (PWM) is one of the common techniques used to implement LED effects. We will discuss how to select a suitable SoC by analyzing the different schemes of implementing LED effects using PWM techniques.

Combining implementation of multiple features in a single SoC invariably poses challenges. It is very important to overcome those challenges for a robust design. We will discuss some common challenges such as crosstalk between LEDs and capacitive sensors, drive strength capability, and LED load transients that cause noise within the capacitive sensing subsystem and how to avoid them.

Power consumption optimization is of high importance for any electronic system. We will discuss design considerations for low power consumption for applications requiring LED effects.

Capacitive touch sensing is the very popular technology used to implement intuitive user interfaces (UI) in many electronics applications including smart phones, tablets, LCD/LED TVs, and

many others. Touch buttons are fast replacing traditional mechanical buttons. However, unlike mechanical buttons which provide tactile feedback to users by their nature, touch buttons need additional components to provide feedback. LEDs are widely used to provide visual feedback and backlight illumination in touch-based UIs.

Combining

(Part 1)and LED LIGHTING

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TECH ARTICLE

9

CAPACITIVE SENSING

By Vairamuthu Ramasamy and Shruti Hanumanthaiah

Some applications require more visual effects apart from simply turning on and off an LED. For example, a laptop may blink the power LED with its brightness gradually increasing and then gradually decreasing when the device is in stand-by. This is called the breathing effect. This is one of the many LED effects such as fading and blinking used in devices. These advanced LED effects, when combined with capacitive touch buttons, improve the aesthetics and the user experience of the system.

It’s often desirable to implement multiple features using a single System-on-Chip (SoC) to reduce the BOM. In this four-part series, we’ll discuss the different aspects of implementing capacitive sensing and LED lighting using a single SoC, including the following topics.

We will briefly describe different LED lighting techniques adopted in capacitive sensing-based UI applications using real-world use cases.

Pulse Width Modulation (PWM) is one of the common techniques used to implement LED effects. We will discuss how to select a suitable SoC by analyzing the different schemes of implementing LED effects using PWM techniques.

Combining implementation of multiple features in a single SoC invariably poses challenges. It is very important to overcome those challenges for a robust design. We will discuss some common challenges such as crosstalk between LEDs and capacitive sensors, drive strength capability, and LED load transients that cause noise within the capacitive sensing subsystem and how to avoid them.

Power consumption optimization is of high importance for any electronic system. We will discuss design considerations for low power consumption for applications requiring LED effects.

Capacitive touch sensing is the very popular technology used to implement intuitive user interfaces (UI) in many electronics applications including smart phones, tablets, LCD/LED TVs, and

many others. Touch buttons are fast replacing traditional mechanical buttons. However, unlike mechanical buttons which provide tactile feedback to users by their nature, touch buttons need additional components to provide feedback. LEDs are widely used to provide visual feedback and backlight illumination in touch-based UIs.

Combining

(Part 1)and LED LIGHTING

1010



GPO0

LED ON Time

CS0


CS0GPO0








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TECH ARTICLE

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GPO0

LED ON Time

CS0


CS0GPO0








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ADVANCED LED EFFECTS

Many advanced effects can be produced by varying the brightness of the LED. Consider a TV front panel having touch buttons to control various operations such as volume. One such panel is shown the picture below.

The panel is made to be completely black and has a shiny surface that matches the bezel and improves the aesthetics. In order for the user to be able to find the controls easily in the dark, the LEDs in the buttons are always lit with low brightness. These LEDs are lit with high brightness upon touch.

PWM is the key technique in LED brightness control applications. By varying the duty cycle of the PWM output, you can adjust the LED brightness as depicted in Figure 4. This enables adjusting your user interface brightness in response to the corresponding button status as well as to ambient lighting conditions. In fact, varying brightness is the basis for all advanced effects such as breathing, fading, etc. We’ll discuss the design parameters of PWM and the various schemes of implementing PWM in part 2.

LED FadingFading is achieved by gradually transitioning from one brightness level to another. Transitioning from a low brightness to a high brightness is called fade-in and the opposite is called fade-out. By gradually changing the duty cycle in a series of small steps between LED states, you can achieve the fading effect (see the figure to the right).

LED BreathingWe discussed briefly the breathing effect at the beginning of this article with an example of the power button in a laptop. Gradually increasing and decreasing the duty cycle between two levels on a continuous basis makes the LED appear to “breath”, as shown in Figure 6. The power button with breathing effect in stand-by mode is an indication to the user that the power button is active and can be operated.

Some vendors already provide configurable devices that implement these advanced LED effects and capacitive sensing in a single chip. An example is Cypress’ CY8CMBR2110 and CapSense MBR3.

t

LED Brightness

100%

ON OFF OFFON

Figure 6. LED Breathing

t

LED

100%

Figure 5. LED Fading

Figure 4. LED Brightness Control

Figure 3. TV Front Panel with Back-lit Touch Buttons

“...VARYING BRIGHTNESS IS THE BASIS FOR ALL ADVANCED EFFECTS SUCH AS BREATHING, FADING, ETC.”

“BY GRADUALLY CHANGING THE DUTY CYCLE IN A SERIES OF SMALL STEPS BETWEEN LED STATES, YOU CAN ACHIEVE THE FADING EFFECT”

In this part, we have explored different LED lighting techniques adopted in capacitive sensing-based UI applications using some real-world use cases. In Part 2, we’ll learn different approaches for implementing PWM.

Vsrc

VDD

ON

ON ON

100%

10%

LED Brightness

DIM

DIM DIM

ON DIMt

tt

13

TECH ARTICLE

13

ADVANCED LED EFFECTS

Many advanced effects can be produced by varying the brightness of the LED. Consider a TV front panel having touch buttons to control various operations such as volume. One such panel is shown the picture below.

The panel is made to be completely black and has a shiny surface that matches the bezel and improves the aesthetics. In order for the user to be able to find the controls easily in the dark, the LEDs in the buttons are always lit with low brightness. These LEDs are lit with high brightness upon touch.

PWM is the key technique in LED brightness control applications. By varying the duty cycle of the PWM output, you can adjust the LED brightness as depicted in Figure 4. This enables adjusting your user interface brightness in response to the corresponding button status as well as to ambient lighting conditions. In fact, varying brightness is the basis for all advanced effects such as breathing, fading, etc. We’ll discuss the design parameters of PWM and the various schemes of implementing PWM in part 2.

LED FadingFading is achieved by gradually transitioning from one brightness level to another. Transitioning from a low brightness to a high brightness is called fade-in and the opposite is called fade-out. By gradually changing the duty cycle in a series of small steps between LED states, you can achieve the fading effect (see the figure to the right).

LED BreathingWe discussed briefly the breathing effect at the beginning of this article with an example of the power button in a laptop. Gradually increasing and decreasing the duty cycle between two levels on a continuous basis makes the LED appear to “breath”, as shown in Figure 6. The power button with breathing effect in stand-by mode is an indication to the user that the power button is active and can be operated.

Some vendors already provide configurable devices that implement these advanced LED effects and capacitive sensing in a single chip. An example is Cypress’ CY8CMBR2110 and CapSense MBR3.

t

LED Brightness

100%

ON OFF OFFON

Figure 6. LED Breathing

t

LED

100%

Figure 5. LED Fading

Figure 4. LED Brightness Control

Figure 3. TV Front Panel with Back-lit Touch Buttons

“...VARYING BRIGHTNESS IS THE BASIS FOR ALL ADVANCED EFFECTS SUCH AS BREATHING, FADING, ETC.”

“BY GRADUALLY CHANGING THE DUTY CYCLE IN A SERIES OF SMALL STEPS BETWEEN LED STATES, YOU CAN ACHIEVE THE FADING EFFECT”

In this part, we have explored different LED lighting techniques adopted in capacitive sensing-based UI applications using some real-world use cases. In Part 2, we’ll learn different approaches for implementing PWM.

Vsrc

VDD

ON

ON ON

100%

10%

LED Brightness

DIM

DIM DIM

ON DIMt

tt

http://www.cypress.com/?id=4370

http://www.cypress.com/capsensembr3/

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COVER STORY

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Plants Prefer Red and Blue

Light, in regard to plant growth, is defined in terms of small particles, also referred to as photons or quantum, whose energy content varies depending on its wavelength. But while most plants spend their days basking in sunlight, only a small sliver of the total light they receive is put to use; the excess only serves to accelerate plant damage and dehydration.

Plants appear green because their leaves reflect green light, a color humans have adapted a keen sensitivity towards. Although advantageous for our foraging ancestors, green light plays no part in the plant’s development. Rather, plant growth is dependent on red and blue light and it’s the symbiotic balance between the Chlorophyll’s ability to absorb different hues of red and blue that determines optimum plant growth. Red light in the 650 – 700 nm range, for example, is ideal for activating photosynthesis, but pure red light causes abnormal plants. Blue light compliments the growth process by telling the leaves when it is time to eat and drink. Because Philip’s Horticulture LEDs are optimally tuned to the plants’ needs, farmers can

eliminate the excess light and benefit from increased yields, earlier flowering, faster growth/germination, better control of plant grown, as well as a more economical use of space.

As Jansen told EEWeb, “What makes Philips’ LED lights unique to horticulture and plant growth is that we develop products based on the plant growth spectrum, which is called the Photosynthetically Active Radiation (PAR) light spectrum that’s between 400 and 700 nm.” The peak of this spectrum is not at yellow—which is where it is for the human eye—but at blue and deep red. In general, the red light is mostly focused on photosynthesis itself and blue is mostly necessary for the morphology of the plants—for forming roots, transportation of water, and more. “Based on these elements, we are designing our products,” Jansen said. “We work on the different intensities in the spectrum to find what the best crop stage is. These lights are much different from the type of LED street lights and consumer lights—here, we are talking about micromoles per second per square meters, which is basically the photosynthetic activity in plants.”

The Environment Prefers LEDs

Traditional methods of reproducing the energy flux of the sun indoors utilize high pressure sodium lamps (HPS) or fluorescent lights that draw a staggering amount of electricity—well into the megawatt range. Behind labor and plants, the energy costs associated with such methods are typically the third highest expenditure for commercial greenhouses. Philips’ Horticulture LED lighting systems can reduce energy consumption by up to 50% and offer a host of other benefits as well and therefore offer growers a significant advantage both economically and environmentally. As Jansen explained, “These products have a much longer lifespan than the current available LEDs. There are no harmful chemicals like mercury that are used in traditional incandescent lights. Because there is less heat in the highly controlled environments, there is also less water use needed to keep the crops alive, which is a big benefit in these urban farm types of applications as well as drought-ridden areas.”

“...plant growth is dependent on red and blue light and it’s the symbiotic balance between the Chlorophyll’s ability to absorb different hues of red and blue that determines optimum plant growth.”

COVER STORY

17

Plants Prefer Red and Blue

Light, in regard to plant growth, is defined in terms of small particles, also referred to as photons or quantum, whose energy content varies depending on its wavelength. But while most plants spend their days basking in sunlight, only a small sliver of the total light they receive is put to use; the excess only serves to accelerate plant damage and dehydration.

Plants appear green because their leaves reflect green light, a color humans have adapted a keen sensitivity towards. Although advantageous for our foraging ancestors, green light plays no part in the plant’s development. Rather, plant growth is dependent on red and blue light and it’s the symbiotic balance between the Chlorophyll’s ability to absorb different hues of red and blue that determines optimum plant growth. Red light in the 650 – 700 nm range, for example, is ideal for activating photosynthesis, but pure red light causes abnormal plants. Blue light compliments the growth process by telling the leaves when it is time to eat and drink. Because Philip’s Horticulture LEDs are optimally tuned to the plants’ needs, farmers can

eliminate the excess light and benefit from increased yields, earlier flowering, faster growth/germination, better control of plant grown, as well as a more economical use of space.

As Jansen told EEWeb, “What makes Philips’ LED lights unique to horticulture and plant growth is that we develop products based on the plant growth spectrum, which is called the Photosynthetically Active Radiation (PAR) light spectrum that’s between 400 and 700 nm.” The peak of this spectrum is not at yellow—which is where it is for the human eye—but at blue and deep red. In general, the red light is mostly focused on photosynthesis itself and blue is mostly necessary for the morphology of the plants—for forming roots, transportation of water, and more. “Based on these elements, we are designing our products,” Jansen said. “We work on the different intensities in the spectrum to find what the best crop stage is. These lights are much different from the type of LED street lights and consumer lights—here, we are talking about micromoles per second per square meters, which is basically the photosynthetic activity in plants.”

The Environment Prefers LEDs

Traditional methods of reproducing the energy flux of the sun indoors utilize high pressure sodium lamps (HPS) or fluorescent lights that draw a staggering amount of electricity—well into the megawatt range. Behind labor and plants, the energy costs associated with such methods are typically the third highest expenditure for commercial greenhouses. Philips’ Horticulture LED lighting systems can reduce energy consumption by up to 50% and offer a host of other benefits as well and therefore offer growers a significant advantage both economically and environmentally. As Jansen explained, “These products have a much longer lifespan than the current available LEDs. There are no harmful chemicals like mercury that are used in traditional incandescent lights. Because there is less heat in the highly controlled environments, there is also less water use needed to keep the crops alive, which is a big benefit in these urban farm types of applications as well as drought-ridden areas.”

“...plant growth is dependent on red and blue light and it’s the symbiotic balance between the Chlorophyll’s ability to absorb different hues of red and blue that determines optimum plant growth.”

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Cooking up a Menu of Light

A diversified team of plant physiologists and engineers combined with years of practical experience and research enables Philips to provide its customers much more than just a product. To gain a deeper understanding of what is required in greenhouses, Philips has partnered with commercial growers, breeders, universities, and research institutes and based on the light research they have conducted they have been able to determine the optimal types of light required for a wide variety of applications. “For different applications, we have different products,” Jansen explained. “For tissue culture—which is a laboratory where research is done on plants to develop certain hard-to-produce plants—certain plants are easier to develop and grow in a laboratory than in a natural environment. We found that we could improve on quantity and uniformity with our fluorescent bulbs versus previous lighting methods in the lab.” For germination rooms, Philips has a product that protects against the high humidity levels. “We have lighting that will replace incandescent lighting for growers that need hard lighting because their crops require more light. We also have applications for interlighting, which is an 8-foot module

that shines in both directions, which can be used in the lower canopy of the crop to produce photosynthesis of high-wire crops like tomatoes, which can grow up to 4-meters tall. If you target each plant’s required light spectrum, you can produce up to 25% more tomatoes, or eggplant, or cucumber.”

The light studies Philips has conducted with its partners over the years has resulted in a vast database of light recipes specifically tailored to a broad range of plants. Plant physiologists based in five different locations throughout the world are continuously expanding the database as they listen to the needs of growers and pinpoint the ideal light solution for a particular plant. “Light is essential to plant growth, but the nature of sunlight is not always available in sufficient amounts for plants and flowers,” Jansen explained. “You can improve nature essentially to be a plant paradise for maximal growth. That’s also what breeders are doing—they are improving genetics to be able to get the best levels in certain conditions. That’s basically what we do with light. The light recipes are based on the research we did in the industry that determine the ideal growing conditions for certain types of crops. The recipes include light uniformity, intensity, nanometer levels, position, and timing.”

“Philips’ horticulture LEDs allow for specific adjustments of color mixing to achieve optimal growth conditions for the plant of choice.”

COVER STORY

19

Cooking up a Menu of Light

A diversified team of plant physiologists and engineers combined with years of practical experience and research enables Philips to provide its customers much more than just a product. To gain a deeper understanding of what is required in greenhouses, Philips has partnered with commercial growers, breeders, universities, and research institutes and based on the light research they have conducted they have been able to determine the optimal types of light required for a wide variety of applications. “For different applications, we have different products,” Jansen explained. “For tissue culture—which is a laboratory where research is done on plants to develop certain hard-to-produce plants—certain plants are easier to develop and grow in a laboratory than in a natural environment. We found that we could improve on quantity and uniformity with our fluorescent bulbs versus previous lighting methods in the lab.” For germination rooms, Philips has a product that protects against the high humidity levels. “We have lighting that will replace incandescent lighting for growers that need hard lighting because their crops require more light. We also have applications for interlighting, which is an 8-foot module

that shines in both directions, which can be used in the lower canopy of the crop to produce photosynthesis of high-wire crops like tomatoes, which can grow up to 4-meters tall. If you target each plant’s required light spectrum, you can produce up to 25% more tomatoes, or eggplant, or cucumber.”

The light studies Philips has conducted with its partners over the years has resulted in a vast database of light recipes specifically tailored to a broad range of plants. Plant physiologists based in five different locations throughout the world are continuously expanding the database as they listen to the needs of growers and pinpoint the ideal light solution for a particular plant. “Light is essential to plant growth, but the nature of sunlight is not always available in sufficient amounts for plants and flowers,” Jansen explained. “You can improve nature essentially to be a plant paradise for maximal growth. That’s also what breeders are doing—they are improving genetics to be able to get the best levels in certain conditions. That’s basically what we do with light. The light recipes are based on the research we did in the industry that determine the ideal growing conditions for certain types of crops. The recipes include light uniformity, intensity, nanometer levels, position, and timing.”

“Philips’ horticulture LEDs allow for specific adjustments of color mixing to achieve optimal growth conditions for the plant of choice.”

20


The plant recipes developed by Philips serve a broad customer base which includes professional fruit and vegetable growers, breeding companies, research institutes, universities, tissue culture companies, and sports stadiums. They have also been targeting medical companies for pharmaceutical uses as well as city farm applications. In order to best ensure their customers are provided the optimal service and support, Philips has partnered with certified horticulture partners to distribute its products. “We are not really working with wholesalers or companies that are selling just boxes in line. These lights are based on science, so we carefully select the partners to choose to get the best results for growers,” Jansen said.

The Future of Farming

City farms offer a viable alternative to traditional practices. Technological advances like Philips Horticulture lighting promise to usher in a new era of farming. “City farms are definitely big things in the future,” Jansen said. “In the US, for example, lettuce or herbs are produced in the winter in northern California or Mexico, and the trucks are driving 5 or 6 days to reach New York City or Boston, so they lose all of the nutritional value. With city farms, you are able to have a grow room, less pressure with insects and diseases, you use much less water and you can grow locally, even in the desert,” concluded Jansen. As the world becomes more populous and precious resources become scarcer, the need for efficient growing methods that do not rely on climate are becoming a necessity.

The Spectrum COOKBOOKSunlight is required for all plant growth. The natural light we get from the sun is comprised of a broad spectrum of colors and frequencies. Essential to plant growth, the chlorophyll found in plants absorbs the red and blue from natural light spectrum and reflects the green, which is why plants appear green to the human eye. The absorption of red and blue allows the plant to perform photosynthesis and to create the ATP molecules necessary for a plants’ energy.

Philips’ horticulture LEDs allow for specific adjustments of color mixing to achieve optimal growth conditions for the plant of choice. The Philips team has coined these special blends of color and light intensity as “light recipes.” To get a better sense of what these light recipes consist of, we spoke with Senior Plant Specialist for the Philips LED department, Dr. Abhay Thosar, about the key aspects of these recipes and how they are developed for the specific application.

What type of work are you doing at Philips?

The main thing I focus on is conducting trials using LEDs and developing light recipes for various crop applications. The reason for conducting the trials is because plants are biodynamic in nature. Each facility or infrastructure is different and the methods of growing will be different as a result. Light, temperature, humidity, and nutrition management are all important factors and when they are in synch with each other, that is when you can expect the optimum response of the plant to any of the treatments.

What is a light recipe? How does your team develop them for specific applications?

When we talk about light recipes, we are talking about two parts. The first part is the quality of light, which includes deep red, blue, and far red. The second part is the intensity of the light. These are the two main components on top of the other environmental factors mentioned earlier. We work closely with the requirements of the grower to develop specific recipes depending on the crop cultivar and how the final product needs to look like. The intensity of the light is measured in micromoles, so we also work on determining the exact amount of micromoles that a specific plant will need at a certain stage in its development. There are many factors that are all considered for the LED recipe.

What is your vision of what these LEDs will enable in the future?

We’ve started seeing a lot of multilayer lighting applications for vertical farming. Initially, these setups started with using fluorescent tubes, but because these lights emit a lot of heat, there were a lot of limitations. Now, with this relatively new LED technology, it is much more feasible to have a real plant factory where you can literally produce the crops based on the timeline and quality that you want. This leads us to the next segment that is really important, which is the medical applications. A lot of the plants produce secondary metabolites, which are used in a lot of medical applications. In our trials that we are conducting in partnership with universities, we are seeing the vitamin and antioxidant contents in these plants a lot higher than normal compared to plants that are grown in natural sunlight. That’s definitely a huge possibility in developing medicinal plants and helping grow secondary metabolite production.

It is now possible to grow indoors and in factory-type settings, so we can also have an effect on the locally grown produce available to communities. Instead of getting a shipment of vegetables that have been sitting in a truck for a few days, they can be grown in a centralized location in a lot of communities, hence reducing the carbon footprint.

“The light recipes are based on the research we did in the industry that determine the ideal growing conditions for certain types of crops.”

COVER STORY

21

The plant recipes developed by Philips serve a broad customer base which includes professional fruit and vegetable growers, breeding companies, research institutes, universities, tissue culture companies, and sports stadiums. They have also been targeting medical companies for pharmaceutical uses as well as city farm applications. In order to best ensure their customers are provided the optimal service and support, Philips has partnered with certified horticulture partners to distribute its products. “We are not really working with wholesalers or companies that are selling just boxes in line. These lights are based on science, so we carefully select the partners to choose to get the best results for growers,” Jansen said.

The Future of Farming

City farms offer a viable alternative to traditional practices. Technological advances like Philips Horticulture lighting promise to usher in a new era of farming. “City farms are definitely big things in the future,” Jansen said. “In the US, for example, lettuce or herbs are produced in the winter in northern California or Mexico, and the trucks are driving 5 or 6 days to reach New York City or Boston, so they lose all of the nutritional value. With city farms, you are able to have a grow room, less pressure with insects and diseases, you use much less water and you can grow locally, even in the desert,” concluded Jansen. As the world becomes more populous and precious resources become scarcer, the need for efficient growing methods that do not rely on climate are becoming a necessity.

The Spectrum COOKBOOKSunlight is required for all plant growth. The natural light we get from the sun is comprised of a broad spectrum of colors and frequencies. Essential to plant growth, the chlorophyll found in plants absorbs the red and blue from natural light spectrum and reflects the green, which is why plants appear green to the human eye. The absorption of red and blue allows the plant to perform photosynthesis and to create the ATP molecules necessary for a plants’ energy.

Philips’ horticulture LEDs allow for specific adjustments of color mixing to achieve optimal growth conditions for the plant of choice. The Philips team has coined these special blends of color and light intensity as “light recipes.” To get a better sense of what these light recipes consist of, we spoke with Senior Plant Specialist for the Philips LED department, Dr. Abhay Thosar, about the key aspects of these recipes and how they are developed for the specific application.

What type of work are you doing at Philips?

The main thing I focus on is conducting trials using LEDs and developing light recipes for various crop applications. The reason for conducting the trials is because plants are biodynamic in nature. Each facility or infrastructure is different and the methods of growing will be different as a result. Light, temperature, humidity, and nutrition management are all important factors and when they are in synch with each other, that is when you can expect the optimum response of the plant to any of the treatments.

What is a light recipe? How does your team develop them for specific applications?

When we talk about light recipes, we are talking about two parts. The first part is the quality of light, which includes deep red, blue, and far red. The second part is the intensity of the light. These are the two main components on top of the other environmental factors mentioned earlier. We work closely with the requirements of the grower to develop specific recipes depending on the crop cultivar and how the final product needs to look like. The intensity of the light is measured in micromoles, so we also work on determining the exact amount of micromoles that a specific plant will need at a certain stage in its development. There are many factors that are all considered for the LED recipe.

What is your vision of what these LEDs will enable in the future?

We’ve started seeing a lot of multilayer lighting applications for vertical farming. Initially, these setups started with using fluorescent tubes, but because these lights emit a lot of heat, there were a lot of limitations. Now, with this relatively new LED technology, it is much more feasible to have a real plant factory where you can literally produce the crops based on the timeline and quality that you want. This leads us to the next segment that is really important, which is the medical applications. A lot of the plants produce secondary metabolites, which are used in a lot of medical applications. In our trials that we are conducting in partnership with universities, we are seeing the vitamin and antioxidant contents in these plants a lot higher than normal compared to plants that are grown in natural sunlight. That’s definitely a huge possibility in developing medicinal plants and helping grow secondary metabolite production.

It is now possible to grow indoors and in factory-type settings, so we can also have an effect on the locally grown produce available to communities. Instead of getting a shipment of vegetables that have been sitting in a truck for a few days, they can be grown in a centralized location in a lot of communities, hence reducing the carbon footprint.

“The light recipes are based on the research we did in the industry that determine the ideal growing conditions for certain types of crops.”

2222


Philips Lumileds has always had a unique position in the color LED

market. With products that span the color range from royal blue

all the way to deep red, it seemed as if the color spectrum had been

covered. However, there is a common gap in color LED lights that occurs

somewhere between green and yellow that cannot be produced with a

typical semiconductor. That’s where Philips Lumileds Lime LEDs come in.

The company’s new LUXEON Rebel and Lime Z LED packages tap into that

gap to provide the most saturated lime green hue available in LED on the

market. EEWeb spoke with David Cosenza, Product Marketing Manager at

Philips Lumileds, about why this previously untapped color will light the

way for new types of LED applications.

LUXEON Z Lime

LUXEON Rebel ES Lime

Going Where No LED has Gone Before

LUXEON LimePhilips Lumileds

LED

23

FEATURED ARTICLE

23

Philips Lumileds has always had a unique position in the color LED

market. With products that span the color range from royal blue

all the way to deep red, it seemed as if the color spectrum had been

covered. However, there is a common gap in color LED lights that occurs

somewhere between green and yellow that cannot be produced with a

typical semiconductor. That’s where Philips Lumileds Lime LEDs come in.

The company’s new LUXEON Rebel and Lime Z LED packages tap into that

gap to provide the most saturated lime green hue available in LED on the

market. EEWeb spoke with David Cosenza, Product Marketing Manager at

Philips Lumileds, about why this previously untapped color will light the

way for new types of LED applications.

LUXEON Z Lime

LUXEON Rebel ES Lime

Going Where No LED has Gone Before

LUXEON LimePhilips Lumileds

LED

2424






and more natural.






25

FEATURED ARTICLE

25





and more natural.






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EEWeb Lighting Electronics - April, 2014