Insomnia & Lighting

[clarencebunsen]

This article touches on a couple topics discussed here: lighting technology & insomnia.


Casting Light on Astronaut Insomnia: ISS to Get Sleep-Promoting Lightbulbs

NASA plans an $11-million upgrade to help space station crews sleep better in orbit

How many NASA engineers does it take to change a lightbulb?

How about if they're changing 85 lightbulbs? What if the bulbs they're replacing are on the International Space Station (ISS)? What if it's rather urgent, because the old bulbs are rapidly burning out? And what if the replacements are a brand-new technology, meant not only to illuminate, but also to help astronauts sleep more?

Those questions are no joke to NASA, which is investing $11.4 million to change out aging fluorescent lights in the ISS's U.S. Orbital Segment. When NASA began considering the replacements, doctors realized they had an opportunity to address an entirely different problem: astronaut insomnia.

www.scientificamerican.com/article.cfm?id=casting-light-on-astronaut-insomnia-iss-to-get-sleep-promoting-lightbulbs

[dave]

Nothing to do with insomnia, but here's what I'm waiting for ... some (affordable) version of Light Sheets. My doctor saw them at a conference and said they're terrific. And their life time expectancy is supposedly measured in decades.

www.flexolite.net/lightsheet.htm

[clarencebunsen]

If I'm doing the arithmetic correctly (conversion between english & metric, remembering the approximate output of a 100 watt bulb & round off) I think you need about 20 of their A4 panels to match the output of a 100 watt bulb. There are a lot of Google hits for electroluminescent panels but they seem pricey.

[dave]

I'm glad you attempted the math. I couldn't remember how to do it. Lux and lumens takes me back to Physics class and Brother Basil giving us a morning quiz while he hung half way out the window on the second floor and finished his after-breakfast cigar. I could never understand what the man said, and I don't mean because his head and one hand holding the Cheroot were out in the rain. Finally, in college I began to get an understanding of physics and realized that my trouble in high school was more than my lackadaisical attitude. Nice guy that he was, Brother Basil didn't know much more about Physics than I did.

The demonstration described to me by my Dr. Phil (that's his name) who in his former life was a PhD software analyst before deciding to become a physician, showed a light sheet the size of a typical ceiling light florescent fixture ... about 18 by 40 ... producing as much light as such a fixture, so he said. Now, whether it cost $18,000 and lasted only a week, he didn't say. But the potential seems to be there.

I like Dr. Phil, having met him not quite a year ago. He's thin man of small stature who runs between 10 and 20 miles three times a week and hasn't touched a carbohydrate in 20 years. "They're killers," he says. We're the same age, but he tells me, "I'm going to last a lot longer than you, Dave."

I tell him he's forgetting about the Luck of the Irish.

[clarencebunsen]

I have a lot of stray numbers stuck in my head. 1 inch = 2.54 cm. 50 mph = 88 fps. 1 gal water = 8 lbs. A match burning for 1 second = 1 BTU. Speed of light in a vacuum = 3 * 10^10 cm/sec.

If you are driving an American Army vehicle in Germany and need to convert km to miles: multiply by 5, divide by 8 and subtract 1 (it takes me about 1 mile to do the calculation).

I remember a 100 watt bulb producing a little less than 2000 lumens. That could be wrong, I'd check if I were actually trying to size something. The site posted gives light output in lumens per square meter but panel size in inches, way too many possibilities for errors when doing mental arithmetic.

[dave]

Sounds about right. WIki says a 23 watt compact fluorescent lamp emits about 1,500–1,600 lumens and I think the equivalence factor I've been keeping in my head is a CF wattage is about 1/4 to 1/3 for roughly the same lumens. You could say that a typical recessed ceiling florescent light fixture in an office building has roughly a square meter of surface, so it should be equivalent to a M2 size light sheet producing 1,000 lumens.

If you were to completely cover a ceiling in a conference room of the size 30 by 40 feet with light sheets, figuring an M2 equivalent to 10 ft2, that would be interesting (and no doubt expensive.)
But you'd have the equivalent of a 50 watt light bulb (1,000 lumens) for every 10 ft2, or in this case 120 light bulbs producing 120,000 lumens. I think it would light up the room. Every other M2 might be better.

Anyway, I found a FAQ.

www.flexolite.net/faq.htm

[chris]

you guys are all so illuminating

[clarencebunsen]

Depending on the time of day either "bright" or "dim bulb" could apply.

[dave]

Chris, CB is the smart one who finds the answers. I just keep wondering about stuff.