LEDs Magazine February 2012 issue

Jan. 27, 2012
The February 2012 issue of LEDs Magazine is now available.

+++ Cover +++

GaN LEDs fabricated on large silicon substrates offer the promise of lowercost manufacturing…if high device performance can be achieved. See page 9. Photo courtesy of Osram Opto Semiconductors.

+++ Features +++

Lumen-maintenance testing for LED lamps, light engines and luminaires
Now that procedures are in place to make long-term lumen-maintenance projections for LED components, efforts are being made to develop methods for testing the lighting system as a whole, as JIANZHONG JIAO explains.

LIGHTINGAre you using all of the lumens that you paid for? The latest LEDs can reliably operate at drive currents well above binning currents, delivering more lumens and robust luminaire life while lowering system cost, explain DAVID COX, DON HIRSH, and MICHAEL MCCLINTIC.
EUROPEEuropean Commission initiates public consultation on LED lighting A Green Paper on LED- and OLED-based lighting published by the European Commission launches a period of public consultation on the future development of SSL in Europe, as TIM WHITAKER explains.
UV LEDsUV LEDs ramp up the quiet side of the LED market Relative to visible LEDs, UV LEDs are a quiet market at only $30 million, yet recent breakthroughs in radiant power and intensity have enabled the displacement of mercury-vapor lamps in applications including UV curing and counterfeit detection, reports LAURA PETERS.
CONTROLSUse of controls escalates in LED lighting despite lack of standards Lighting companies are moving forward with adaptive-control technology that can save significant energy especially when combined with inherently-efficient LED sources, explains MAURY WRIGHT. However, no standards exist that would allow interoperable use of luminaires, sensors, and controllers from different vendors.
LIGHTINGLED lighting at Louvre symbolizes Toshiba's move into Europe A ceremony has been held to mark the first phase of a project to install LED exterior lighting at one of Europe’s great art museums, writes TIM WHITAKER.
OPTICSTIR optics enhance the illuminance on target for directional LED modules Secondary optics using total internal reflection perform better than reflector-based optics for constructing directional LED-based modules, but only if the light-distribution pattern is correctly evaulated, write WU JIANG and KEVIN SCHNEIDER. OPTICAL SAFETYLED-based products must meet photobiological safety standards: part 3To conclude our series of articles on LED photobiological safety, LESLIE LYONS puts IEC62471 to work in consideration of the hazards posed by today’s LEDs and LED-based products.
DESIGN FORUMLow-voltage LED lamps present unique driver challenge MR16 sockets present a significant retrofit-lamp opportunity for LEDs, explains KAMAL NAJMI, but installed transformers complicate the design of a drop-in SSL replacement. LAST WORDColor-quality standards bodies need to consider the broad user base Work on a new and improved measure of color-rendering quality has apparently stagnated in the CIE, and the failure leaves the broad lighting community without a tool that would be very useful, says MAURY WRIGHT.

+++ Columns/departments +++

Uncertainty remains the order of the day


  • US spending bill delays lamp-efficiency enforcement
  • DOE study finds no LED replacement for post-top street lights
  • LEDs shed new light on social housing