Shining Bright: Holiday LED Lighting 2013

‘Tis the season for LED holiday displays. Here’s a round-up of some rather interesting displays in 2013.

Rockefeller Center, New York, New York

This world famous Christmas tree at Rockefeller Center, a 75-year-old Norway spruce, is illuminated by 45,000 rainbow LEDs and features a 550 lb., 9.5-foot-wide Swarovski crystal star on top.

Rock Center xmas 2013 2

 

 

 

 

 

The National Christmas Tree, Washington, DC

GE provided the design and lights for the National Christmas Tree for the 51st time this year. This year’s tree features 110 LED net lights and 225 LED string sets – all Energy Star® qualified, and 265 LED spherical ornaments. The total wattage is about 5700 watts – saving 80% energy as compared to incandescent holiday lights.  That’s equal to saving one ton of coal, and nearly a 5700-pound reduction in carbon dioxide emissions.

National Xmas Tree 2013

 

 

 

 

Trafalgar Square, London, England 2013

Each year since 1947 Norway’s capital city Oslo has donated Christmas tree for Trafalgar Square, to thank Britain for its support during World War II.  The tree stands 20 meters tall and features about 900 LED lights.

Trafalgar Square 2013 Tree

 

 

 

 

 

Rio De Janeiro, Brazil

Sponsored by Bradesco Seguros, this Rio tree is the largest floating Christmas tree in the world. Towering 85 meters into the sky, the tree floats slowly around the Lagoa Rodrigo de Freitas in Rio’s Zona Sul (South Zone) throughout the holiday season.  It features over three million microlights, two thousand strobe effects, one hundred meters of hoses and one hundred LED reflectors.

Rio X mas Tree

 

 

 

 

 

Delray Beach, Florida

The 100-foot tall Christmas tree is festively illuminated with over 15,000 LED lights, carefully decorated with 39,000 ornaments, and contains 3000 branches.

Del Ray Beach 100 Ft Christmas Tree

 

 

 

 

 

 

The Shiodome, Tokyo, Japan

The Caretta Shiodome, a shopping, dining and entertainment complex, located in the elegant 51-story Dentsu Building, hosts the “White X’mas in the Sea” featuring a vast ocean of LED lights and an illuminated, animated display on the walls of the shopping center.  The light show incorporates interactive 3D projection mapping, allowing visitors to influence the appearance of the video sections of the illumination and the rhythm of the soundtrack by clapping their hands.  Here’s a link to a video showing how the display was put together as well as its premier complete with school kids clapping.

Tokyo Shiodome 2013 Xmas

 

 

 

 

 

 

 

 

For Further Reading

Clearlysapphire.com, The Evolution of Christmas Lights – From Incandescent to LED, http://blog.clearlysapphire.com/?p=313

 

Large Diameter Patterned Sapphire Substrates Explained

Rubicon Technology offers large diameter PSS in a range range of shapes including cone, dome and pyramid as well as custom.

Rubicon Technology offers large diameter PSS in a range of shapes including cone, dome and pyramid and range of orientations.

While LED chip manufacturers have been using patterned sapphire substrates (PSS) for years, there’s growing interest in large diameter PSS.  Recently, Rubicon Technology announced the commercial availability of large diameter PSS.  During their latest earnings call, they indicated that they’ve received interest from 7 major LED chip manufacturers for 4- and 6-inch large diameter PSS.  Why the interest from LED chip manufacturers?

First, PSS helps improve epitaxial growth by promoting growth of the GaN in parallel to the substrate surface. This also helps reduce the number of dislocations, called the dislocation density, which can degrade performance of an LED.  Secondly, patterning can help extract as much as 30 percent more light from an LED.  This is particularly advantageous for high brightness LEDs (HB LEDs) that are used in LED lighting applications.

Second, the evolution of patterning large diameter substrates brings economical advantages to LED chip manufacturers, especially those anticipating demand from the LED lighting market.  Large diameter sapphire wafers help LED chip manufacturers cut costs by enabling more throughput for each run of the MOCVD reactor.  This helps chip manufacturers make better use of the reactor “real estate” and decreases the cost per unit of area processed because of the curvature of the larger wafer.  The outer curvature of a 6-inch wafer is less, enabling greater use of the surface area than the tighter curvature of a 2-inch wafer resulting in less edge loss.  Larger diameter wafers also provide post-MOCVD efficiencies.  Depending on the type of MOCVD reactor used, LED chip manufacturers using six-inch wafer platforms may achieve up to 48% greater usable area per reactor run compared with two-inch wafers.  These efficiency gains become very compelling when manufacturers want to ramp up LED chip production to support greater volumes of LEDs for light bulbs.

Finally, LED chip manufacturers have been buying smaller 2-inch and 4-inch PSS from outside suppliers for years.  The next step in the evolution in the market is the migration to large diameter PSS for the reasons we mention above.  While some LED chip manufacturers will have specialized patterning needs and the resources to keep the work in-house, others will not.  Some LED chip manufacturers may not have the expertise and equipment to move to large diameter PSS, so having a ready, trusted supplier will prove handy.

For Further Reading

ClearlySapphire, LED Lighting Spotlight: Patterned Sapphire Substrates http://blog.clearlysapphire.com/?p=390

Semiconductor Today, Patterned sapphire for nitride enhancements, http://www.semiconductor-today.com/features/SemiconductorToday_SeptOct_PatternedSapphire.pdf

Compound Semiconductor, New Wet Process For LEDs On Patterned Sapphire Boosts Efficiency, http://www.compoundsemiconductor.net/csc/news-details.php?cat=news&id=19734296

Compound Semiconductor, Rubicon Orders Multiple Profilers For Sapphire Production, http://www.compoundsemiconductor.net/csc/news-details.php?cat=news&id=19735318

Clearlysapphire.com, Larger Wafers, Larger Yield – The Numbers Behind Large Diameter Sapphire Wafers and Yield, http://blog.clearlysapphire.com/?p=435