Next time you build a laundry room or pick bright white paint for a home office’s walls, think twice about installing LED bulbs, lighting experts at Penn State University warn. That’s because the whiteners that manufacturers use to give products a “whiter than white” look typically contain fluorescent materials that won’t glow unless the light’s color range includes violet or ultraviolet.
Sunlight, fluorescent light, and incandescent light all do that, a news release from Penn State notes. On the other hand, most current LED bulbs use blue LEDs to excite a phosphor that then glows white. And because there’s no violet or ultraviolet light cast, the fluorescent materials in “whiter than white” goods don’t get activated.
A Penn State student and researchers from Soraa, a lighting company, tested this issue by asking 39 people to observe various combinations of light sources and white objects and choose which were brighter. The testers found it easiest to pick among the choices when they were using light sources with more violet in the light’s color range.