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General questions
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| Salvo | Date: Tuesday, 24.06.2014, 19:57 | Message # 1 |
 Star Engineer
Group: Local Moderators
Italy
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| In this thread you can ask any kind of question, preferably technical ones. (not related with astronomy)
Do LEDs emits UV light?
I ask this question because I lost the glass "shield" located on the Flash LED of my mobile phone. I use that flash a lot and I'm worried it might me a dangerous source of UV rays...
The universe is not required to be in perfect harmony with human ambition.
CPU: Intel Core i7 4770 GPU: ASUS Radeon R9 270 RAM: 8 GBs
(still don't know why everyone is doing this...)
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| Billy_Mayes | Date: Tuesday, 24.06.2014, 20:49 | Message # 2 |
 Pioneer
Group: Users
Finland
Messages: 485
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| Quote Some industry sources claim that LEDs produce no UV radiation. This actually isn’t true. LEDs do produce a small amount of UV, but they emit even less. That’s because the amount that is produced is converted to white light by the phosphors inside the lamp.
I found this site by just googling your question.
http://www.leapfroglighting.com/lighting_and_uv_radiation/
AMD Phenom II X4 955 3.2 GHz Quad-Core - AMD Radeon HD 6950 2GB VRAM - 4GB RAM - 1680x1050 75 Hz Samsung screen
Edited by Billy_Mayes - Tuesday, 24.06.2014, 20:50 |
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| Salvo | Date: Tuesday, 24.06.2014, 22:32 | Message # 3 |
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Star Engineer
Group: Local Moderators
Italy
Messages: 1400
Status: Offline
| Quote Billy_Mayes (  ) I found this site by just googling your question.
Interesting, actually my Flash LED lost any sort of "lamp" outside, you can see the circuits (i know, it's dangerous for water), do you think it's the same?
The universe is not required to be in perfect harmony with human ambition.
CPU: Intel Core i7 4770 GPU: ASUS Radeon R9 270 RAM: 8 GBs
(still don't know why everyone is doing this...)
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| Gabe | Date: Wednesday, 25.06.2014, 08:27 | Message # 4 |
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Astronaut
Group: Users
Canada
Messages: 42
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| What is the coolest stone you guys have ever seen with your own eyes? 
Commander Shepard of the SSV Normandy, reporting for duty.
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| Watsisname | Date: Wednesday, 25.06.2014, 09:07 | Message # 5 |
 Galaxy Architect
Group: Global Moderators
United States
Messages: 2613
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| Coolest gemstone I've ever seen with my own eyes:
http://mineralsciences.si.edu/collections/dom-pedro/gallery.htm
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| Billy_Mayes | Date: Wednesday, 25.06.2014, 09:20 | Message # 6 |
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Pioneer
Group: Users
Finland
Messages: 485
Status: Offline
| Quote Salvo ( ) Interesting, actually my Flash LED lost any sort of "lamp" outside, you can see the circuits (i know, it's dangerous for water), do you think it's the same?
Hmm... I am by no means an expert on this, but I'd think the amount of UV light produced
would be small enough to safely use it.
I'm not sure if the phosphors are completely gone, if the lamp is gone, since that's the important part in converting the UV light.
The picture here here shows the phosphor covering the LED. Again, this is just me guessing.
AMD Phenom II X4 955 3.2 GHz Quad-Core - AMD Radeon HD 6950 2GB VRAM - 4GB RAM - 1680x1050 75 Hz Samsung screen
Edited by Billy_Mayes - Wednesday, 25.06.2014, 09:20 |
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| Salvo | Date: Wednesday, 25.06.2014, 11:21 | Message # 7 |
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Star Engineer
Group: Local Moderators
Italy
Messages: 1400
Status: Offline
| Quote Billy_Mayes ( ) The picture here here shows the phosphor covering the LED.
Actually it might still have phosphors, I made a picture showing it...
However, thanks Billy_Mayes for your help 
Quote Gabe ( ) What is the coolest stone you guys have ever seen with your own eyes?
"Valle Della Luna" (Sardinia), I don't have the photo of the stone itself, but there are many cool ones there!
The universe is not required to be in perfect harmony with human ambition.
CPU: Intel Core i7 4770 GPU: ASUS Radeon R9 270 RAM: 8 GBs
(still don't know why everyone is doing this...)
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| Voekoevaka | Date: Wednesday, 25.06.2014, 12:19 | Message # 8 |
 World Builder
Group: SE team
France
Messages: 1016
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| Quote Gabe ( ) What is the coolest stone you guys have ever seen with your own eyes? biggrin
The Giant's Causeway is too a very amazing stone formation. I was there two weeks ago.
Want some music of mine ? Please go here !
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| Billy_Mayes | Date: Wednesday, 25.06.2014, 12:19 | Message # 9 |
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Pioneer
Group: Users
Finland
Messages: 485
Status: Offline
| Quote Salvo ( ) However, thanks Billy_Mayes for your help
No problem. 
Quote Gabe ( ) What is the coolest stone you guys have ever seen with your own eyes?
At a mall here in Finland, there's this store that sells gems and jewerly. They have this giant stone that's hollowed out (you could probably fit inside there), and the inside is covered with purple gems. It costs 10,000€, so no-one has bought it yet.
As for one I found myself, I was walking alongside a brook, when I saw this really black rock in the river. I picked it up and rinsed it off. It was really black, like the darkest stone I've ever seen. The other side was slightly more smooth, probably from the water eroding it on one side of constantly. I accidentally lost it though. 
AMD Phenom II X4 955 3.2 GHz Quad-Core - AMD Radeon HD 6950 2GB VRAM - 4GB RAM - 1680x1050 75 Hz Samsung screen
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| Gabe | Date: Wednesday, 25.06.2014, 23:28 | Message # 10 |
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Astronaut
Group: Users
Canada
Messages: 42
Status: Offline
| WOW nice find, Billy_Mayes
Here in Canada, BC actually, we have really rocky beaches. One day I went with my family to this one beach with A LOT of rocks (big and small) and as I was walking along the shore I noticed this rock about the diameter of a 2 dollar coin with faint red "cracks" all over it. Here is the cool thing about this rock: I accidentally dropped it in water and when I went to pick it back up, the faint red cracks were now a bright red. Best stone I have ever found in my life. I think I still have it here in my house somewhere. If I find it, I'll post some before and after pictures.
Commander Shepard of the SSV Normandy, reporting for duty.
Edited by Gabe - Wednesday, 25.06.2014, 23:30 |
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