Est. 1998 — 27 years of woodworking knowledge
Question for Bill Tindall and others on LED light
Barry Irby
I read somewhere that there is no such thing as a white LED. They are really blue and covered with phosphors that glow white. The problem is that the blue light is harmful to humans and while we can't see it, it has the potential to damage Eyes and skin and can penetrate the skin.
Is it true there is an underlying problem with LED's?
Re: Question for Bill Tindall and others on LED li
David Bassett
Most white LED's are in fact blue diodes coated with a (mix of) phosphor that emits a version of a white spectrum when excited by blue light. In theory they don't leak the blue light. (in practice, I'm sure some escapes. But white light includes blue, so I'd assume the better products compensate.)
Of course fluorescent lights are a UV emitting plasma that stimulates phosphor to generate white light. This leakage seems to me to a bigger problem....
Re: Question for Bill Tindall and others on LED li
Dave Bair
Blue light is part of the natural color spectrum of visible sunlight and occupies the 450-495 nm range. It is not invisible. I cannot locate a proven source that calls it harmful. The ultra violet range of sunlight is not visible and can cause both harm and benefits to humans.
Re: Question for Bill Tindall and others on LED li
Bill Tindall, E.Tn.
I read somewhere that there is no such thing as a white LED. True
No such thing as white fluorescent either.
They are really blue and covered with phosphors that glow white. One means to white appearing light is to use a LED that emits UV light and use it to excite phosphors like in a fluorescent lamp. The phosphors can be diddled with to more or less, depending on LED quality, simulate white light appearance. The success will show up in the CRI value. There are other ways to get white looking LED light.
The problem is that the blue light is harmful to humans and while we can't see it, it has the potential to damage Eyes and skin and can penetrate the skin. there is so much wrong here I don't know where to begin.
Is it true there is an underlying problem with LED's? no
Is it true there is an underlying problem with LED's? No
Thanks, David, Dave and Bill
Re: Question for Bill Tindall and others on LED li
Bill Howatt
Supposedly there is a link between blue light exposure and poor sleep. If you look at your cell phone there likely is a blue light filter setting on it to reduce the blue.
Bill