LEDs in Action – Performance Art and Fish Bellies

Now that the summer is nearly over (in the US), we thought we might take a look at some fun applications of LEDs including performance art, art turned into football replays, and fish bellies.

Eugene, Oregon-based fiber optic toy company Ants On A Melon, has turned LEDs into performance art. Founded in 2012, the folks at Ants On A Melon have developed an artistic platform designed to share interactive fiber optic artwork.  Their LED performance art using jellyfish is just one example of what they can do with LEDs. You can see a video of the Jellyfish (pictured below) here.

Ants On A Melon, Jellyfish, Performance Art

Ants On A Melon, Jellyfish, Performance Art







The Dallas Cowboys new stadium, AT&T Stadium, is filled with art, including a new LED-based exhibit by LED artist Jim Campbell, “Exploded View (Dallas Cowboys) 2013.”  Exploded View features 2880 LED’s that flicker and illustrate plays in LED lights. A renowned LED light artist, Campbell specializes in low-resolution images.  From close up, the image is completely abstract, but from far away, the football play is recognizable. While we don’t have a video of this artwork, here’s a link to a video of Campbell’s Exploded View, Commuters.

Campbell’s artwork is included in the permanent collections of the Museum of Modern Art in New York, the Smithsonian American Art Museum in Washington, D.C., and the de Young Museum in Golden Gate Park in San Francisco.

Jim Campbell's Exploded View, Dallas Cowboys

Jim Campbell’s Exploded View, Dallas Cowboys








While not performance art, the new LED art exhibit at Texas State University, San Marcos River in San Marcos, Texas, by public art designers Joe O’Connell and Blessing Hancock encourages interaction.  Designed to celebrate the biodiversity of the San Marcos River, Fish Bellies enables students to sit inside, study or talk while touch controls allow them to adjust the color and saturation levels of the LED lighting inside.

Fish Bellies at Texas State University, San Marcos River

Fish Bellies at Texas State University, San Marcos River








For Further Reading

The Dallas News, LED artist has created the 50th piece in the Cowboys Stadium collection, http://www.dallasnews.com/entertainment/columnists/michael-granberry/20130427-led-artist-has-created-the-50th-piece-in-the-cowboys-stadium-collection.ece

Inhabitat.com, LED Fish Bellies Celebrate Biological and Human Diversity in Texas, http://inhabitat.com/led-fish-bellies-celebrate-biological-and-human-diversity-in-texas/

Alternative Substrates – Dimming the Hype

Two-inch, Four-inch and Six-inch Sapphire Wafers

Two-inch, Four-inch and Six-inch Sapphire Wafers

Today, more than 80% of LEDs are made based on sapphire wafers.   Recently, Lux Research published a report, Dimming the Hype: GaN-on-Si Fails to Outshine Sapphire by 2020, about the state of alternative substrates.  In LED production, sapphire is used as the substrate onto which the chemicals that will become the emitting layer of the LED are deposited as a vapor.  With the LED lighting market expected to grow to $80 billion, Lux Research expects the substrate market to grow to $4 billion in 2020 making it a highly attractive market.  Lux expects sapphire to continue to dominate the substrate market.

“Silicon is already widely used for electronics, and some LED die manufacturers are hoping to take advantage of silicon substrates,” said Pallavi Madakasira, Lux Research Analyst and lead author of the Lux report.  She explained that GaN-on-Si presents technical challenges such as cracking and a lattice mismatch that reduces the performance of LEDs based on the alternative substrate.

In an interview with Compound Semiconductor, Madakasira spoke about LEDs based on silicon substrates.  She doesn’t buy the argument that GaN-on-silicon makers can save on costs.  She says that even if they use fully depreciated CMOS equipment, the process of depositing complex buffer layers onto silicon prior to GaN deposition to overcome GaN and silicon lattice mismatches, adds time and cost to a manufacturing line.

Madakasira also shared performance data in her report with Compound Semiconductor. She notes that alternative substrates haven’t provided the performance of sapphire.  According to Lux, the luminance efficacy of GaN-on-SiC LEDs is 200 Lumens per Watt with GaN-on-sapphire devices coming in at between 150 to 180 Lumens per Watt.

What does this mean?  The Lux report concluded that sapphire will remain highly competitive for the rest of the decade.  GaN-on-silicon, will snare only 10% market share while GaN-on-silicon carbide will grow to 18% of the market.   Where do they fit? Here are Lux’s conclusions:

  • Choice and cost of LEDs will determine adoption. Where GaN-on-sapphire is suited to all applications, GaN-on-bulk GaN will be relegated to niche commercial lighting and GaN-on-Si, with unproven performance, will be better suited to cost-sensitive residential applications.
  • Four-inch wafers will rule (for now), though six-inch wafers start to come into vogue. Four-inch wafers will peak at 62% market share with $2.1 billion in 2017 sales. Later, the LED industry will move towards 6” epiwafers, which will take a 35% share, equivalent to $1.4 billion, in 2020.
  • Technology will advance sapphire substrates. Sapphire substrate manufacturing technology has advanced significantly with specialists such as Rubicon and Monocrystal demonstrating substrates up to 12” in diameter. New methods like hydride vapor phase epitaxy (HVPE) will further improve throughput and cut costs, keeping sapphire highly competitive for the rest of the decade.

For Further Reading

Lux Research, Epi-Wafer Market to Grow to $4 Billion in 2020 as LED Lighting Zooms to $80 Billion, http://www.luxresearchinc.com/news-and-events/press-releases/182.html

Compound Semiconductor, Sapphire Substrates to Lead Future LED Markets, http://www.compoundsemiconductor.net/csc/indepth-details/19736669/Sapphire-substrates-to-lead-future-LED-market.html

Confused about Your Home Lighting? – LED, CFL and Incandescent Compared

Switch 3-Way LED Light Bulb

Switch 3-Way LED Light Bulb

Incandescent lighting was the most effective way to produce light for more than a century.  Now, there are new alternatives to light your home. Here’s a quick guide to understand the differences between LED light bulbs, compact fluorescent bulbs (CFLs) and traditional incandescent bulbs.  First, let’s start off with the basics:

Incandescent Light Bulbs

Incandescent light bulbs remain unchanged since Edison invented the light bulb in 1879.  A traditional light bulb uses electricity to light a tungsten filament that gives off light when it heats up inside of a bulb filled with an inert gas.  This is a very inefficient way to produce light since incandescent bulbs give off most of their energy (as much as 80 or 90 %) as heat rather than light.

In 2007, US legislators imposed strict energy efficient guidelines impacting 100W incandescent light bulbs in the Energy Independence and Security Act of 2007.  The 100 Watt incandescent bulb was officially phased out in the US in January 2012.  California was slightly ahead with a date of January 1, 2011.  The 75 Watt bulb effective date was January 1, 2013 (California, 1/1/2012). The 60 Watt and 40 Watt bulb effective dates for phase out are January 1, 2014 (California, 1/1/2013).


A descendant of traditional fluorescent lights, CFLs contain argon and mercury vapor housed within that spiral-shaped tube. The bulbs rely on an integrated ballast to produce an electric current that passes through the mixture of gasses, exciting the gas molecules that produce the light.  The time for the ballast to produce the electrical current causes that typical CFL delay when it is turned on.  CFLs use 20-30% less energy than the typical incandescent and last 8 to 15 times longer.  Of course, they do contain mercury, so cleaning up after breaking them and disposing of CFLs after they burn out becomes problematic.  Here’s a link to how to dispose of CFLs safely for you and the environment.

LED light bulbs

Unlike traditional incandescent bulbs, LED light bulbs generate light using a small “package” of several LEDs in a light bulb.  LED light bulbs are more efficient since they use a semiconductor to emit light or photons when electricity is passed through it.  LED light bulbs give of more than 80% of the energy used as light. The good news is that LED light bulbs can cut household energy use by as much as 80% and have a lifetime of 25,000 hours or more.

How do they stack up?

Here’s a graphical look at how each stacks up comparing Cree and Philips LED light bulbs to typical GE and Philips CFLs.  The information was developed using Home Depot’s web site using the “Lighting Facts” package labeling required by the US government.  You can link to the DOE’s web page about the labels for more info.

What does Lumens/Watt mean?   This is a measure of how well the light source produces light.  The higher the number, the better your light source is at producing light.

What’s the Color Rendition Index? The CRI is a measure of the color of the light and the way the light affects objects.  We noted the type of color of light: warm, soft or bright in this field.

For Further Reading

US DOE, Solid State Lighting Basics, http://www1.eere.energy.gov/buildings/ssl/ssl_basics.html