Categories
General Lighting Fixtures Future of technology LED Technology

White LED Lighting Tunes In to Protect Precious Artwork

museum lighting 1

The Warsaw National Museum in Poland has joined the ranks of art museums around the world who are choosing LED for their display lighting. Along with institutions such as the Louvre, the WNM has chosen to upgrade their fixtures to all LED luminaires with no exceptions.

The WNM is a safe haven for more than 800,000 historical works of art by Polish and European artists, with items dating back as far as the 8th century. These delicate pieces require precise conditions if they are to be maintained and preserved, including minimized exposure to light and UV rays. The directors of the WNM’s primary goals for the lighting upgrade were to employ state-of-the-art preservation techniques, bring out the best qualities of the pieces with the highest possible light quality, and reduce their carbon footprint by minimizing electrical energy use.

The museum has opted to use Zumtobel’s Arcos LED spotlights, which can be easily re-configured to suit any changes in the exhibits. The fixtures have been modified with Tunable White technology. Based on PI LED technology developed by Lumitech, co-marketed by Tridonic, the Tunable White technology allows LEDs to efficiently produce the full spectrum of white light via a combination of blue LEDs with green-tinted phosphor, red LEDs and blue LEDs. An integrated DALI (digitally addressable lighting interface) controller system can adjust the color temperature of the light as needed, or each lamp can be adjusted by hand.

The LED fixtures give curators an element of control they did not previously have. Fixtures can be individually adjusted to bring out the best of each piece, such as a warmer white light to bring out the golden undertones of a medieval painting. The WNM, unlike other museums, uses almost no natural light from the outside. The upgraded LED fixtures provide maximum illumination without the damaging effects of UV rays and, during certain hours, are operated by proximity sensors so that light exposure as well as energy use is minimized.

So far, the museum has renovated five main galleries, equating to a 40% reduction in energy use. The total reduction in energy load is expected to be from 110,000W down to 22,400W, representing a decrease of 80%. Developments in LED technology continue to make them the best energy efficient lighting option. With accoutrements like wireless controls and precision color rendering, it is likely that LED will continue to take over in applications such as museums where presentation is key.

Categories
General Lighting LED

Good News for the Environment: Americans Have Embraced LED

Osram Sylvania has released their seventh annual socket survey and I, Dr. Bulb, believe the results are encouraging. It seems that the speedy development of LED technology has helped raise it to the top of the lighting market. Osram’s report shows that 78% of Americans surveyed have made the switch from incandescent to LED.

LED lighting has, since its inception, made a slow but steady climb to the top of the lighting market. At first, the high cost of production made LEDs more expensive than most people could afford. Despite the long term savings, many were not willing to make the initial investment. For a time it was the compact fluorescent (CFL) bulb which held dominance over the energy efficient lighting market. However, for both the LED and the CFL, the bright blue-white light was an off-putting factor that sent many traditionalists running for the incandescent bulbs.

Now, advancements in LED technology have reduced the initial price point with more efficient materials that are easier to produce and better CRI that is friendlier to the human eye. As the “human centric lighting” movement gathers speed, LED products are currently in production that are able to change their color temperature to suit the consumer’s needs. LEDs have gained ground in other aspects of technology as well. Recent developments in Visual Light Communication (VLC) have made incredible smart lighting technologies possible.

The Osram Socket Survey indicates that 62% of Americans are aware of innovations in smart lighting, though only 10% have actually purchased smart bulbs for their homes. Although the latter number is small right now, Osram’s findings indicate the the smart lighting trend will continue to grow: 83% of Americans surveyed believe smart lighting is a great start to home automation with 72% believing that smart lighting will soon replace all traditional lighting technologies.
The outlook for the future of energy efficiency is, pardon the pun, very well lit. The majority of the consumers surveyed who use LED bulbs belong to the Millennial generation, demonstrating in clear numerical facts that the ‘kids these days’ are doing their part to help the environment. The continued trend in LED adoption and development of home automation via smart lighting innovations could be a turning point in the way the US uses energy.

Categories
General Lighting LED

The Evolution of Human Centric Lighting

As lighting technologies advance, researchers have been studying the negative effects of blue light emitted by modern mobile devices on human sleep patterns. During the course of our evolution, bright blue-white light (like an LED or computer screen) was only available from the sun during the daytime, with the much more subtle light from the moon and stars at night.  As the sun slipped past the horizon and turned the light from blue to red, it signaled to our bodies that it was time to sleep.

This natural response to the pattern of color shifting light has always been a part of our biological design. Previous technologies—like incandescent lights and candles—did very little to interrupt the sleeping patterns, also called circadian rhythm, of mankind. The warm glow of candlelight, reminiscent of sunset, is less confusing to our bodies. However, as energy efficient LEDs and bright blue-white computer displays continue to infiltrate our homes, their influence has an increasingly negative effect on the human circadian rhythm.

In the past, electric lighting was a way to stave off the darkness, and there was no real thought given toward the potential consequences of using artificial lights. Many of the benefits of natural light may never be replicated by artificial lights, but there are ways to avoid the negative interruptions in our sleep patterns that bright blue indoor lighting can cause. Recent innovations in the development of “human centric lighting” have created smart LED products with optimum lighting that can be adjusted in brightness and color temperature.

The Silk Smart LED lamp matches its light output to a user’s circadian rhythms. It produces bright blue light for specific parts of the day while switching to dimmer red-tone light for evening hours. In addition, these smart LED lamps have a hub that can be connected to a home WiFi. Users are able to program the lamp to adjust for specific times or they can control its output remotely using an app on their smartphone.

Other major human centric lighting projects include Arborlight’s new LED panels for offices and homes that imitate the light intensity and temperature of the natural light outside. Since spending up to 90% of their lives indoors, 20% of which is at work, is typical for most people, their overall well-being can be determined by the lighting environment in the workplace. At work and at home, innovations in human centric lighting could lead to better health and happier lives.

Categories
LED

Farms of the Future: The Advance of Agricultural LED Lighting

Fluorescent, induction, and high-intensity discharge lighting are slowly becoming obsolete sources for indoor agricultural lighting applications. Often the sheer variety of types of lamps can be staggering, and identifying the best candidate to imitate actual sunlight can provide a challenge. In situations where opportunities for natural lighting is limited, such as urban gardens, new research is providing alternative lighting methods that prove to be economically viable, in comparison to traditional growth-promoting lighting methods.

Early Attempts

Historical data dating back to the mid-19th century reveals that agricultural lighting mimicked the typical use of lighting by individuals and industry. Though the intent was true, incandescent filament lighting was not designed for agricultural applications, and produced sustained elevated levels of infrared radiation and heat that caused abnormal stem growth in many species of vegetation.

Over the past 150 years, lighting designed for transportation and highways, as well as warehouses and manufacturing facilities, has been used in the growing of vegetation with results that were rather limited in realizing the full potential for generating bountiful harvests. Practical at the time of their use, traditional forms of indoor agricultural lighting such as fluorescent, and high intensity discharge lamps, often were found to waste a good portion of the energy which it consumed, which resulted in elevated electrical expenditures, thus compromising the intent of indoor gardening.

Stepping Into the Light

With advances in contemporary lighting technology, through years of research and in-field applications, scientists have discovered that LED lights are the most practical and cost efficient method for stimulating the indoor growth of vegetation. Technology has made it possible for LED lighting to facilitate the necessary photo-morphological and photosynthetic requirements of vegetation. This enables vegetation to grow at a quicker pace, without waste, and in more locations.

LED lights are lightweight and need not be situated close to vegetation, as fluorescent bulbs necessitate. They do not need costly cooling systems as traditional lighting methods do. By developing methods to control and manipulate the colors of light produced, the latest generation of agricultural lighting appears dimmer to the human eye but is designed to create optimal conditions for photosynthesis. This can reduce energy consumption and its associated costs up to 70%, making this technology accessible and cost-effective for a wide variety of applications.

The advent of LED light for indoor agricultural applications is a contributing factor to reducing food shortages around the world. Practical in situations where the terrain is not compatible for vegetation growth, LED lighting foster’s innovative ways to grow vegetation. As this technology develops, it becomes easier than ever to picture a world where low cost, fresh food is available, regardless of climate, year round.

Categories
General Lighting Fixtures LED

Is LEP Technology the Next Bright Idea in Lighting?

Over the last decade LED’s (Light Emitting Diode) have become the technology of choice in the lighting industry. Another technology called Light Emitting Plasma (LEP) has begun to gain traction as a viable alternative for applications requiring high illumination. Not only is the lighting industry taking notice, even the mainstream media has started reporting on the benefits of LEP lighting.

How LEP Lighting Works

Plasma in the lighting industry, refers to sources that have a continuous spectrum. LEP systems have three components: an emitter, a driver, and a power supply. Each emitter has a quartz capsule with a blend of gases and halides that emit light at a certain spectrum. A highly reflective material in the housing causes the light to emit forward. The driver is, at its simplest, a solid-state RF amplifier that creates electrical energy to a fully-sealed quartz lamp without electrodes or filaments. Because the electrical field is highly concentrated, it ionizes the gases and vaporizes the halides to create a plasma inside that lamp to produce and intense light source.

No electrodes, glass-to-metal seals, or other materials offer simple construction allowing the LEP to be efficient yet rugged. Benefits of this design include:

  • no waste of heat energy.
  • elimination of glass-to-metal seals.
  • no quartz wall darketing that produces lumen depreciation and failure.
  • faster warm-up and restrike times.

LEP light sources are possible today because the wireless revolution has produced cost effective, efficient, and reliable solid-state amplifiers. In addition to energy savings, LEP technology has other important attributes. LEP lighting may be dimmed to 20% output. These lamps also have a 50,000-hour life at 70% lumen maintenance, where has halide lamps have a life of 18,000 hours. Warmer color temperatures for LEP are also on the horizon.

Complements LED Usage

In most applications where high illumination is required, LEP does not compete with LED lighting. Rather, it serves as a high-output complement. To that end, LED may be used for low and medium illuminance while LEP can take over high illuminance needs because of smaller lamp size. LED and LEP lighting have the same approximate cost at the 5,000-lumen level, but LEP’s small size makes it much more cost effective as lumen output increases. LED’s, however, are more effective in their ability to scale down.

Categories
General Lighting LED

GaN on Silicon: A New Era for LEDs

LED lighting offers an increasing number of benefits for people who choose to make the switch from incandescent. Progress in LED performance continues to develop at a phenomenal rate, with the average LED efficiency currently sitting at 50%. Some laboratory tests have produced LEDs with an efficiency as high as 60% and it is expected the number will continue to rise. With such productive energy use and an extensive operating life, LEDs are taking over the market for lighting. The one gating issue to the seemingly inevitable success of the light emitting diode is the cost to produce them.

Scientists are seeking to solve the issue by developing a method of producing LEDs which will utilize more affordable materials. In the early 1990s, japanese researcher Shuji Nakamura developed a method of growing thin gallium-nitride (GaN) layers on sapphire substrates to produce high-brightness blue LEDs. As you might imagine, sapphire is an expensive substrate material and certainly adds to the cost of LED production.

A strong candidate for the replacement of sapphire is silicon. Although the material is much more common and more cost effective, there are still some obstacles to overcome. Semiconductors are characterized by the amount of space between the atoms in the crystal lattice. For optimal results, the substrate atoms should be spaced at the same distance as the atoms in the GaN layer. The mismatch causes strain which in turn causes sporadic dislocations of atoms. As a result, electrical current can leak and the LED performance is impaired.

Researchers have already begun working on several solutions to the problem. A mirror on the surface of the LED replaces the substrate after it is used to grow the GaN layer. The structure of the LED is flipped and the light is generated upwards. In addition, the high refractive index of GaN creates a narrow cone through which light can escape. By roughening the surface, scientists have been able to remove the total internal reflection (TIR) restriction. Further enhancements to light output can be made with the addition of a lens.

It is expected that, as research continues over the next few months, that GaN-on-Si LEDs will match the performance of GaN-on-Sapphire LEDs. The use of silicon as a substrate will accelerate the market for LED lighting. With the ability to reduce LED production cost while also cutting energy consumption, homeowners, property owners and other consumers are likely to save hundreds of dollars annually on their lighting related expenses.