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Question on filtering high-frequency "blues" out of white LED light...
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Dave
Feb 14, 2009, 2:14:28 AM2/14/09
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Found some ultra-bright white LEDs at my local electronics candy store, and
built an emergency lantern out of them. Problem is, the light hurts my
wife's eyes, causing stabbing pain that does not go away immediately after
the light is turned off. Her patience with my experimentions is running
thin. I am thinking I need to talk to someone at a camera store to see
about a serious filter, to make the bright blue-white light "warmer" and
less painful for her. The effect is similar to that caused by the bluish
headlights on some of the newer cars, but far more painful for her. Anyone
with ideas on what it is I am trying to filter out would be welcome to hear
from just about now. Please feel free to post speculations and the result
of any knowledge or experience you have. Planning on calling a camera store
tomorrow (Saturday, 2/14/09) but don't know what to ask for. If anyone has
thoughts they would care to share I am all ears. This "emergency lantern"
provides a very bright light that, according to my calculations, should last
at least 72 hours on one set of batteries, and possibly even more. It also
doesn't blind you as it only lights up the half of the room you are looking
at (standing behind it). I would like to keep it, but need to make it
adaptable to her optic nerves...
built an emergency lantern out of them. Problem is, the light hurts my
wife's eyes, causing stabbing pain that does not go away immediately after
the light is turned off. Her patience with my experimentions is running
thin. I am thinking I need to talk to someone at a camera store to see
about a serious filter, to make the bright blue-white light "warmer" and
less painful for her. The effect is similar to that caused by the bluish
headlights on some of the newer cars, but far more painful for her. Anyone
with ideas on what it is I am trying to filter out would be welcome to hear
from just about now. Please feel free to post speculations and the result
of any knowledge or experience you have. Planning on calling a camera store
tomorrow (Saturday, 2/14/09) but don't know what to ask for. If anyone has
thoughts they would care to share I am all ears. This "emergency lantern"
provides a very bright light that, according to my calculations, should last
at least 72 hours on one set of batteries, and possibly even more. It also
doesn't blind you as it only lights up the half of the room you are looking
at (standing behind it). I would like to keep it, but need to make it
adaptable to her optic nerves...
Many thanks for any ideas or feedback.
Dave
Going to go Google "visible light" and possibly look up same in Wickipedia
(sp?). Now curious as to the wavelength I am trying to filter out...
Dave
Feb 14, 2009, 3:06:09 AM2/14/09
to
"Dave" <db5...@hotmail.com> wrote in message
news:HdmdnVxCPpXH8gvU...@posted.internetamerica...
Okay, after reading about the dangers of high-energy blue light I realize I
need to talk to our eye doctor tomorrow. Forget the camera store. She says
her eyes still hurt, and I am hoping I have permanently damaged her retinas.
From a datasheet on this particular LED, its CCT is 9000K. Far and above
the visible range of 2000-7500 (according to an article referrenced in
Wikipedia, not the Wikipedia article itself.) I knew it was bright, but had
no idea how bright.
Dave
Dave
Feb 14, 2009, 3:16:37 AM2/14/09
to
news:Z56dnUPAV-3h5gvU...@posted.internetamerica...
Correction: "Have NOT permanently damaged her retinas."
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