LED Specification Issues

Important Considerations When Specifying LED Lighting Fixtures
Consistent color temperature between fixtures, thermal management and future serviceability are some of the most important issues to consider when selecting a quality LED fixture. Less expensive and poorly designed fixtures that do not address these issues can experience color shift, shortened lifetimes, loss of efficiencies and few options to replace or upgrade the LED engine in the future. It has been Pathway’s goal to never compromise the quality and benefits of LED's as a source when designing our solid state lighting line. Pathway Lighting has addressed these issues by using tight binning, remote phosphor technology, advanced thermal management, and quality LED sources. We have designed all of our solid state fixtures to be serviceable or upgradeable if the need ever arises.

Importance of Binning LED Chips
When LED chips are manufactured they all vary in color from chip to chip.  Therefore a reputable manufacturer will “bin” them.  This means that each one is tested, color is evaluated, and then sorted based on the outcome.  This is a costly process for the LED manufacturer, but necessary so that LED lighting fixtures will provide consistent color from fixture to fixture.  The LED engines that we use in our products only feature “tightly binned” LED chips.

Currently, most LED emitters now have to be ANSI binned to even be considered for Energy Star™ or light engines.

Why Remote Phosphor Technology is Superior
While "white" light covers a wide array of the visible spectrum. LED dies by nature emit light in very narrow bands of the visible spectrum.  To make LED's emit “white” light the LED die is doped with a phosphor coating applied directly to the die. While still being an efficient way to create white light, the very nature of covering the die limits efficiencies and may lead to color shift over time. Remote phosphor technology addresses this issue by using the spectrum of light emitted by un-doped dies to excite a remote phosphor plate. It is this plate that then produces the usable white light and directs it into the optics. There are several inherent advantages to this approach including better efficiencies from the bare dies, more uniform color consistency between fixtures, and less color shift over time. This technology was developed and patented by Philips and Pathway Lighting has worked closely with them since the beginning to ensure successful integration into our line. It is this technology that is present in our 4VLED & 4SQLED lines of square and round aperture downlights with more fixture and aperture options on the way.

Importance of Heat Management
While LED’s produce no forward heat in the light output, the heat generated by the process of converting electrical energy into usable white light must be addressed to realize the full benefits of this technology. Pathway’s design process includes rigorous thermal qualification and use of the latest thermal management techniques to overcome this issue. We integrate precisely engineered heat sinks and thermal transfer materials into our fixtures in conjunction with active cooling on our larger lumen output fixtures.

What is Active Cooling?
In larger output packages a static heat sink is sometimes not enough to effectively dissipate the heat generated by the engine. So in addition to a heat sink we employ a state of the art patented Synjet® cooling module developed by Nuventix. This approach uses a vibrating diaphragm that provides a turbulent airflow around the cooling fins of the heat sink to better dissipate the heat. As there are no moving frictional parts to wear out, this approach has the benefits of long life and virtually no audible noise levels. A demonstration of this technology can be found by clicking this link:  http://www.nuventix.com/synjet_flash_demo  

Long Term Commitment
Many specifiers have concerns that because the LED technology is rapidly evolving, there will not be replacement modules for an existing fixture 15-20 years from now.  This is not true as Philips has made a long term commitment to the technology used in their Fortimo™ products.  This “future-proofing” policy insures that replacement engines or drivers will be available that will interface and perform just like the original.  As the technology improves, so too will performance and efficiency.  A fixture that produces 1100 lumens at 20 watts today may, in the future, produce 1100 lumens at a much lower wattage.  The important issue is that the new LED module will be compatible with the downlighting fixture that was installed today and it will offer the same color and lumen output.

Breakthrough in LED Efficiency
Philips has announced that that it has improved the 2000 Lumen Fortimo™ from 45 lm/W to 63 lm/W.  At Pathway we’ve made it mandatory to align ourselves with companies that have made the commitment to this kind of technological advancement as well as quality, performance, longevity and “future-proofing”.  We will not align ourselves with the less expensive, no-name LED products that are out there.