Under Some LEDs, Different Whites May Appear Uniform
News from Laboratory Equipment:

Penn State Univ.

For years, companies have been adding whiteners to laundry detergent, paints, plastics, paper and fabrics to make whites look “whiter than white.” But now, with a switch away from incandescent and fluorescent lighting, different degrees of whites may all look the same, according to experts in lighting.

“Retailers have long been concerned with the color-rendering qualities of their lighting, but less aware how light sources render white,” says Kevin Houser, professor of architectural engineering at Penn State Univ.

Not long ago, the only practical choices for home, office or commercial lighting were incandescent or fluorescent bulbs. More recently, compact fluorescent bulbs, which use less energy than incandescent bulbs, became popular, but compact fluorescents are not always accepted by consumers because of poor color rendition, inability to be dimmed by users, slow warm-up to full output and because they contain mercury.

The most recent popular entry into home or commercial lighting are light-emitting diode (LED) bulbs, which while currently expensive, are often even more energy-saving than compact fluorescents.

While some LED bulbs will make colors pop, the vast majority do not showcase or differentiate the ap…………… continues on Laboratory Equipment

… Read the full article

Related News:

Shining a spotlight on streetlights
News from Minnesota Daily:

I try to catch the bus after class, but with erratic schedules, I end up missing it at least once or twice each week. I walk home begrudgingly, remembering the string of thefts earlier this school year and when my own house was broken into in October.

Too often I’m faced with deciding the safest route to my house. Should I take the quicker way, where I know several streetlights have been out for weeks? Or should I go the long way and hope that better lighting and higher traffic make my walk safer? Most nights I take the latter pathway, but I shouldn’t have to make this choice.

The city of Minneapolis does not do a good enough job of keeping its streets lit. The same lights stay out for weeks at a time on and around campus.

The city also does not do a good enough job of educating the community on what to do if someone sees that a streetlight has burned out. Until recently, I did not know that it was the responsibility of city residents to call 311 or Xcel Energy if a streetlight is out. If you don’t see any action after several weeks — the city takes a couple of weeks on average — it’s your duty to continue pestering Xcel Energy or city officials. And residents seem to be trying: The city saw a 46 percent jump in streetlight repair requests in the last…………… continues on Minnesota Daily

… Read the full article