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 Replies: 9 / Views: 2,867 |
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Pillar of the Community
Canada
1700 Posts |
Back in 2012 I really wanted the first Glow-in-the-Dark Dinosaur, but it soon sold out and the price hiked up four times. I bought one recently for around $70 from Colonial Acres. I got it not too long ago.
I turned off the lights in the evening the other day and it didn't glow. I found out that I had to charge it under light before it can be achieved. I did that, and it worked.
The box glows by itself without being "charged". Same thing goes for my wristwatch which glows during the night even though it's under my sleeves all the time. What is it about the surface of the coin that makes it only glow after being charged?
I look forward to hearing about the science behind this.
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Pillar of the Community
Canada
2845 Posts |
Good for you, you gave great patience to wait it out 4 years and still be interested! I don't know about your watch or the box, but glow-in-the dark paint that charges with light is Phosphorescent. https://wikipedia.org/wiki/Phosphorescence |
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Pillar of the Community
Canada
6768 Posts |
Quote:
The box glows by itself without being "charged". Same thing goes for my wristwatch which glows during the night even though it's under my sleeves all the time. What is it about the surface of the coin that makes it only glow after being charged? I do not know the scientific explain, but if it V8 turbocharged, it really powerful. Well, speaking seriously: the difference between the coin and the box, that on the box the glowing paint on top, so in order to glow, it still has to be "charged", but daily light, that accumulated is enough. While on the coin, the glowing paint is covered (or mixed) by other layer (cause the skeleton not visible in the day light), so in order to glow in the dark - it has to be charged by really bright and close source of light. |
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Bedrock of the Community
United States
10034 Posts |
Your watch may have a tritium element making it always glow. I had one in the 70s and loved it. Tritium is an isotope of Hydrogen that naturally gives off a green glow. The tritium watch I speak of kept batteries a lot longer b/c there was no need for a light inside the watch.
It was a bit like a TRON-like thing. So back then I thought the tritium watches and technology would have taken over the market, but for some reason they never did. I once heard it was found the tritium was not healthy to be around, but yet I see they can still be bought.
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Pillar of the Community
Canada
2019 Posts |
Hmmm its funny how we take these technologies for granted these days lol. Its quite interesting the history of GITD stuff. Quote:
The Science Behind Glow in the Dark
"Glow in the dark" falls under several different sciences including:
Photoluminescence by definition is the emission of light from a molecule or atom that has absorbed electromagnetic energy: examples include fluorescence and phosphorescence materials.
The glow in the dark plastic constellation kits that you stick on your wall or ceiling are an example of a photoluminescence based product.
Bioluminescence is the light emitted by living organisms using an internal chemical reaction (think deep sea creatures)
Chemiluminescence is the emission of light without the emission of heat as the result of a chemical reaction (for example glowsticks),
Radioluminescence is created by the bombardment of ionizing radiation.
Chemiluminescence and photoluminescence are behind the majority of glow in the dark products. According to Alfred University professors, "the distinct difference between chemical luminescence and photo luminescence is that for light to work via chemical luminescence a chemical reaction has to occur, however during photo luminescence light is released without a chemical reaction. Quote:
Glow in the Dark - History
Phosphorus and its various compounds are phosphorescents, or materials that glow in the dark. Before knowing what phosphorus was, its glowing properties have been reported in ancient writings. The oldest known written observations were made in China, dating back to 1000 B.C. regarding fireflies and glow-worms.
In 1602, Vincenzo Casciarolo, discovered the phosphorus glowing "Bolognian Stones" just outside of Bologna that started the first scientific study of photoluminescence.
Phosphorus was first isolated in 1669 by German physician Hennig Brand. Brand was an alchemist who was attempting to change metals into gold when he isolated phosphorus.
All photoluminescence glow in the dark products contain phosphor. To make a glow in the dark toy, toymakers use a phosphor that is energized by normal light and that has a very long persistence - the length of time it glows. Zinc Sulfide and Strontium Aluminate are the two most commonly used phosphors. http://inventors.about.com/od/gstar...ow_stick.htm |
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Valued Member
Canada
71 Posts |
Earle42, slightly off topic, but the tritium watches at that time used tritium mixed in with the paint for the markers to create luminescent markers and hands, most watches now use a non-radioactive compound like SuperLuminova for luminous markers and hands. Current tritium watches actually have the tritium isolated in small sealed tubes.
Of course you can still buy older tritium paint marker watches on the secondary market, and if you're really into the vintage stuff older ones that used radium in the paint to create the glow. That was legitimately dangerous, for reference look up the story of the Radium Girls, the workers who contracted radiation poisoning painting watch dials in the early 20th century.
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Pillar of the Community
 Canada
1700 Posts |
Redbarchettayyz,
I'm really glad you posted. I learned quite a lot from your post and from briefly researching what you mentioned.
For the coin, it makes a lot of sense. Phosphorescence requires the absorption of light before the emission of light.
I knew about many other incidences involving nasty things kept away from workers, but I didn't know about Radium poisoning.
The beta particles emitted my Swiss watch (I assume it's Tritium) shouldn't even be close to having the ability of harming my health. It's interesting that the half life of tritium is 12 years. So I guess the glow will decrease by 1/2 by then.
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Bedrock of the Community
United States
10034 Posts |
@Redbarchettayyz Thanks for this info. Mine was an LCD with the sealed capsule behind the screen. It had no paint or numbers since it was not analog. I have seen a couple for sale (name brand "Sensor")on ebay from that time period. No doubt those for sale are old enough they don't glow anymore. |
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Valued Member
Canada
71 Posts |
No problem, one of my big hobbies is watches so I don't mind at all.
Peter, yes, it will decrease, but it will be gradual enough that it will just add to the character of the watch!
Earle, they prbably don't glow anymore, but they'd still be a cool period piece. I looked up the old Sensor Trilite and LC, they definitely stand out!
On the subject of the coins, I'd really like to pick up one of the glow in the dark NCLTs one day just to have one in the collection.
Also, a quick way to supercharge phosphorescent material, like on the coins, is a couple seconds with a blacklight torch. This is done with watches to get impressive glowing lume shot pics, and I'm sure you could get some pretty cool coin pics using the same method.
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Bedrock of the Community
United States
10034 Posts |
Yes, my Sensor Trilite was so bright that I used to read at night by it with no trouble. It was as bright as some of those single light LCD flashlights that first came out. If I was in a dark room, its glow was easy to see through the material on my shirt sleeve.
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Replies: 9 / Views: 2,867 |
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Posted 06/15/2016 10:23 pm
