While definitely not the same, there should be an opportunity for something costing less than $35,000 while still getting closer.
For example here is DIY 90,000 lumen flashlight that supposedly cost $250-350:
https://www.youtube.com/watch?v=-JVqRy0sWWY&t=3m40s
Using 10 of these LED chips:
http://www.ebay.com/itm/100W-Warm-White-3000K-LED-Light-High...
Maybe milk could be used? :)
http://2.bp.blogspot.com/-wyj6iHUndhg/UXpUk6HxfLI/AAAAAAAACu...
http://thestandardmodel.blogspot.com/2013/04/when-i-was-chil...
It feels like they charge so much not because there would be some principal engineering / technical obstacle but simply because they can. They have been the first who realized something like this can be done (now that LED lighting progressed so far) and for rich customers this is a feature that's highly desirable, so they are willing to pay so much.
They do have a good marketing. Their business model depends on others thinking there is some special magic.
I had to see that reddit post to even start questioning that something like this could be replicated.
This is the type of 'simple' invention that you could never really anticipate but changes the future profoundly.
Well, maybe in one more generation once the resolution becomes higher.. and adding hand tracking.. and a UV lamp on a servo..
Let's hope you don't have a significant other that you're supposed to be spending time with.
Come on, this isn't a solution.
1. http://www.google.com/patents/US8469550
The energy use would be heavy, but it might be worth the cost given the transportation energy savings and higher productivity and happiness of the city population.
Here's to hoping this tech gets commoditized and indoor spaces get a lot more pleasant.
I was expecting this to be slightly more common by now.
... or even make el cheapo version with just bluish tinted mirror.
It's nice, but it's not $30,000 nice. Still, the cost of LEDs per lumen continues to drop. LED auto headlights are now below $100.
There's a market for this in hospitals, to keep patients in intensive care units in sync with the outside world. Fake windows with lighting tied to the day/night cycle have been used. Here's someone looking for funding for a startup to do a really good virtual window.[1]
It does look very realistic, but makes me wonder whether having an uneven light distribution is desirable or whether it's something that's needed to trick the body.
The sun availability does seem to affect my daily energy and motivation.
One of many possibilities to consider: https://en.wikipedia.org/wiki/Seasonal_affective_disorder
However, for far less than this you can get a lamp that provides a similar effect, if not the same aesthetics.
This was on Product Hunt a while ago: https://www.producthunt.com/tech/coelux
(Not your fault though - their website is pretty sparse on information.)
[0] http://www.coelux.com/en/solutions/index
[1] http://www.hispotion.com/coelux-artificial-lighting-system-t...
...and obligatory musical reference: https://www.youtube.com/watch?v=txPqV0lZaSE
With the added benefit you could use a low-power light for those distances.
Source: Me in wintertime Sweden.
For circadian light you just need something that is sufficiently bright and blue. ... or just blue for that matter, blue LEDs are cheap and efficient.
None of this can improve surroundings that are otherwise unpleasant...
A building's function is to block unpleasant sun, but a window's function is to let it in and to control it. Artificial sunlight could enable more control over the sunlight factor.
Regarding circadian rhythm, it is not fully understood and blue light may not be the only important factor. Perhaps the visual sense that there is sunlight is also an important cue. But yes, blue light is clearly important. I would hope that any public lighting system would strongly take it into account.
For example, the color and feel should reflect what happens in the natural world! The LED lights being installed on city streets right now might cause problems for us (not to mention the blue light in our screens).
Unpleasant surroundings take a huge toll on people in cities. I am dismayed by the noise, pollution, lack of overhead cover, and threatening cars when I walk around SOMA and so many other places. A single tech like artificial sunlight won't cure all ills, but it is a tool that will help cities become larger and more livable.
Construction robotics, new materials, methods to better maintain plants and trees, and obviously transportation are also important tools in this fight.
There must be some scientific knowdlegde regarding this that I ignore.
What we consider sunlight is essentially the light emitted by any object at 6000K, which is reasonably easy to achieve but somewhat difficult to contain. And actually mimicking the sun is usually not the best method (for one, the unfiltered UV would be very unhealthy). It's possible to approximate the visible part of that light though, and we're gradually getting better at it.
I replace bulbs like Johnny Appleseed. I see an incandescent bulb that matches the soft yellow temp? Out it goes, gets replaced with a Cree bulb.
Worst smelling light ever. You could even say that that idea stinks!
OTOH a colloidal solution of silver could potentially do the job.
In computer graphics, if you want to get "daylight" illumination for cheap, you simply use two lights - one white-to-yellowish directional and one bluish hemispherical:
http://threejs.org/examples/webgl_lights_hemisphere.html
You only compute expensive scattering if you need volumetric effects (e.g. god rays or atmospheric fog blueing things far away, on the order of at least hundreds of meters).
But here for simple indoor lighting, you don't really need volumetric effects. You just need proper light color coming from roughly appropriate directions - one strong white-to-yellowish light (coming from uniform direction) that will cast hard shadows and one weaker bluish diffuse light (coming from many directions) that will cast soft shadows.
Real physical double-light would look better - this demo lacks ambient occlusion for hemispheric component (soft shadows in real world are free, in rendering they are expensive).
My understanding is that (a) utilization of dietary vitamin D is significantly lower than naturally produced D (from sun exposure) and (b) vitamin D is one of several micronutrients produced from sun exposure.
The end product of UVB irradiated skin (i.e., sunlight) is vitamin D3. (D3 is "activated" locally in tissues utilizing it.) Ingested D3 supplements effectively add to the body's supply, though the optimum intake is controversial and varies among individuals.
One difference between sunlight and supplements is that D3 production via UVB exposure has an upper bound, only so much can be made because there's a limited amount of substrate available in skin cells to convert to vitamin D. The upshot is sunlight is "safer" re: potential toxicity of excessive vitamin D intake.
AFAIK vitamin D is unique among nutritional factors in its reliance on UVB exposure. Don't know of any other micronutrients directly related to sunlight, but possible there's something I've overlooked.
So the advise is to take D supplements only if recommended by a doctor.
Presumed deficiency of D (per lab studies) is quite common here and supplementation is usually recommended for optimum health. Besides location, lifestyle factors often reduce sun exposure increasing chances of low D level.
There are tradeoffs involved with most recommendations. The common advice to avoid UV exposure re: melanoma risk has propelled manufacture of sunscreens into a big industry. Sunscreens filter out nearly all UVB, and interfere with forming D. Ironically, low body stores of D may increase cancer risk according to some studies. BTW my dermatologist knows about that, nonetheless advocates minimizing cancer risk, worrying less about vitamin D deficiency or risks of supplementation.
Indigenous Alaskan populations were always vulnerable to D deficiency yet it was uncommon, probably associated with their diet, rich in the oils of sea-going animals, known sources of D. Out of curiosity, a while back based on published info I calculated their intake of vitamin D was roughly 1500-2000IU/day. This seems consistent with opinions of some researchers re: appropriate intake level (don't have the references at hand--I can locate them if there's interest).
The jury's still out on vitamin D in terms of its functions and dietary requirement. It is a fascinating story that with any luck will be at least better resolved in my lifetime.
As for D supplements, one really should very careful even in cases of high latitudes (and this is the reason I avoid D supplements despite living at 61th parallel). Quoting Paul Albert , http://bacteriality.com/wp-content/uploads/2009/08/Albert_IO... :
So are we really facing an epidemic of vitamin D "deficiency" or are we simply beginning to note more signs of an imminent epidemic of chronic disease – an epidemic which would be exacerbated by increasing the amount of vitamin D added to our food supply?
