Shows such as Lightfair International (LFI) always result in yet-to-be-announced products going on display, and in the case of Cree, such products were arguably the hit of its exhibit. The company demonstrated a retrofit tube that is designed to be affixed with plastic brackets into existing troffers, and an LED-based canopy light that delivers a more-traditional glare-free light courtesy of a diffuser.
The florescent-tube retrofit space has been a compelling target for solid-state lighting (SSL) manufacturers due to the large number of installed florescent troffers. But LEDs haven't proven a perfect match for tubes, and lately safety concerns have arisen over whether fluorescent end sockets can hold the weight of an LED tube, and whether line voltage should be applied through such sockets in a retrofit scenario in which the ballast is removed from the fixture.
Cree addresses the safety issue with its approach. The tubes require replacement of the ballast with a dedicated LED driver that must be first mounted into the troffer. Then the tubes are attached via plastic clips affixed typically with self-tapping screws driven into the fixture sheet metal. The formal announcement of the products should come in a matter of weeks.
The Cree CPY fixture for canopy lighting is also due to be announced within a few weeks. The design is a departure from the familiar fixtures that integrate LEDs, each with total internal reflector (TIR) optics, visible as point light sources.
The exposed LED sources can cause glare especially at the lower mounting heights of canopy applications, although the TIRs are meant to evenly distribute the beam. Still the diffuser generates more uniform light. Cree said that the design uses LEDs mounted on a planar surface and only the diffuser as a secondary optic.
Presumably the constant efficacy gain in the LED arena has resulted in companies having the luxury of using diffusers and still getting the desired light output. One maker of canopy and garage SSL products, Kenall, has used a diffuser from the start in its products. Indeed Kenall uses both TIR lenses and a tertiary diffuser but claims that its products deliver superior photometric performance.
We will be closely following the lighting market to see if diffusers become more popular. In a separate LFI story on Cooper lighting, we also mentioned a canopy fixture that uses light-guide technology. And that fixture produces diffuse light as well.