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marbLED

marbles in the dark
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(+13)
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Marbles fitted with a long-life battery and a small LED light in the core. A light sensor activates it when the lights are turned down....a really innexpensive gimmick with the kids

Glow-in-the-dark ones already do exist, but thats a tired concept.

The same concept could also be used to make an adult version - simmilar to the already available popular marble-esque type feng-shui pebble stones....

shinobi, Nov 25 2004

(?) LEDs in superballs - they're everywhere... http://www.bunnygra...com/newproducts.htm
link for [jutta]'s anno [ConsulFlaminicus, Nov 26 2004]

(?) How marbles are made http://www.landofma...m/marbles-make.html
[calum, Nov 26 2004]

Glass engraving, then melting with a blowtorch https://goo.gl/photos/CWek7m4ZjM3aMezf6
Then it exploded as soon as I touched it once it had cooled (too rapidly). [Ian Tindale, Jan 03 2017]

Polarisation at Wiki https://en.wikipedi...olarization_(waves)
It's a bit wordy (and equationy...) [neutrinos_shadow, Jan 03 2017]

Two-Particle Photon Theory Two_20Particle_20Photon
From our own [steam_cannon] [neutrinos_shadow, Jan 03 2017]

[link]






       I'd want to play marbles....for the first time forty years or so.....[+]
normzone, Nov 25 2004
  

       You played marbles in your 20s?!
bristolz, Nov 25 2004
  

       One small change I'd make: turn them on when they're shaken, not when it's dark. (Otherwise, they'll spend most of their life glowing to themselves inside a package or bag.) Something like that already exists in bouncing rubber balls with embedded LEDs.   

       This is cool - no idea why it isn't sold yet.
jutta, Nov 25 2004
  

       Yes, impact sensors could indicate which marbles had been hit while playing.
Ling, Nov 25 2004
  

       To add to the fun, there are some new technologies a-comin' down the pike that scavenge vibration and general kinetic energy to generate tiny amounts of electrical power when an item is moved, hit or jiggled. So there's no need for a battery at all - the light goes on as the marble is used, and when it's quiescent, it stays quiescent. How Newtonian!
phlogiston, Nov 25 2004
  

       An excellent concept and a more fodder for playground oneupmanship. However, marbles are made by melting glass down and rolling it (see link) so how do we get the LED inside?
calum, Nov 26 2004
  

       mold em
umm0i, Nov 28 2004
  

       Mold 'em, mold 'em / Shake 'em and hold 'em / Put 'em in the dark and then / Watch 'em glow golden
spiritualized, Nov 28 2004
  

       Molten glass is very hot. My guess is that even considering the small amount of glass required, there would be enough heat present to damage the LED and battery. This would result in a high failure rate, driving the cost up and making them playthings only for the very rich. Inevitably, a dual-tier toy system would arise, resulting in class-division, economic upheaval, probably famine.
xrayTed, Nov 29 2004
  

       Lovely idea.
Pericles, Nov 29 2004
  

       Missed this one. (+)   

       //Molten glass is very hot.//   

       Hmm. You could still do this by gluing together two glass hemispheres, with the electronics embedded in clear resin in the middle.   

       Actually, what's the lowest-melting glass? People have developed plenty of low-melting metal alloys, why not glasses?
MaxwellBuchanan, Jan 02 2017
  

       //why not glasses?//   

       Or resins.   

       I'd add a solar panel. And RFID in case you lose them.
bigsleep, Jan 02 2017
  

       //Or resins.//   

       Possibly, but you want the density, scufflessness and clickiness of glass.
MaxwellBuchanan, Jan 03 2017
  

       Soda Lime glass will slump at a lower temperature than Borosilicate will, however, the latter has a lower coefficient of thermal expansion, which is a very useful property.   

       I recently glass engraved a glass (which is something I used to do a lot of, decades ago) and as an experiment, melted the engraved area with a blowtorch for a prolonged time. Realizing that the glass would be subject to thermal stresses without an annealing stage (I don't have an annealing kiln handy) it was only a matter of a short amount of time before it would smash itself to pieces. I could tell because I held my ipad up behind it (to act as a polarised light source) and held my polarising ray-bans up in front of the glass, and I could see a concentrated pool of rainbow around the blowtorched area. It did shatter - I brushed my finger against the engraved abraded heated area and it popped and smashed into pieces. Oh well.
Ian Tindale, Jan 03 2017
  

       By the way, if you want to see some absolutely captivating glasswork in a technical context, look for Dalibor Farny on youtube.
Ian Tindale, Jan 03 2017
  

       //I held my ipad up behind it (to act as a polarised light source) and held my polarising ray-bans up in front of the glass//   

       That is clever - will have to try.
MaxwellBuchanan, Jan 03 2017
  

       See the pix in the link (comparison photos with and without - one of the only times I found having polarising lenses actually useful rather than distracting) (the glass engraving is a bit rough and quick as I knew it would probably end up like this one did).
Ian Tindale, Jan 03 2017
  

       Cool! I wonder if my pair of 3D polarizing glasses will work?
MaxwellBuchanan, Jan 03 2017
  

       [MaxwellBuchanan], your 3D movie glasses are (probably) a left- and a right-handed pair of circularly polarised lenses; what you want is proper linearly polarised sunglasses.
neutrinos_shadow, Jan 03 2017
  

       You're probably right. Rotating them in front of my screen causes the image to brighten/darken only by maybe 50%. If I look at my old LCD calculator through them, one lens change the background brightness by 100% depending on rotation, while the other lens has no effect.   

       I am beginning to suspect that I actually know much less about polarization than I thought I did. In particular, if vertically polarized light has the electric field wobbling up and down; and horizontally polaried light has the field wobble left and right; then what in gods' names does circularly polarized light do??
MaxwellBuchanan, Jan 03 2017
  

       (Getting some-what off-topic...) polarisation of light is a messy business (see linky). I'm not entirely sure I understand it myself (even after doing a reasonable amount of optics at university).
It is one of the reasons I am a fan of the "two-particle photon" theory (linky).
neutrinos_shadow, Jan 03 2017
  

       Scarabs, mantis shrimps, firefly larvae all do circular polarisation. Some mantis shrimps claim to be able to detect it (though they were probably lying when they were asked).   

       Modern DSLR cameras will often require the use of circular polarising filters instead of the proper linear sort everyone normal grew up using, because the linear ones will fuck up the through-the-lens autofocus.
Ian Tindale, Jan 04 2017
  

       Do circular polarisers come in clockwise and anti-clockwise variants?
hippo, Jan 04 2017
  

       I don't know, I've never owned one (only the normal ones). I know they don't actually state on the box whether they're left handed or right handed wave, or even if this varies across manufacturers.   

       One way to think about this sort of thing is imagine a skipping rope between two people, like those Double-Dutch videos Malcolm McLaren popularised in the early 80s. If they wave the rope up and down at each other, and you look at it from the side, it'll look like it is going up and down. If instead they swung the rope round and round in a circle (as they do), but you're still looking at it from the side, like the audience, and you don't have any depth perception or binocular vision, you'll still measure an up and down motion of a wave. If you're from the viewpoint of the rope-holding person, it's a circular motion.
Ian Tindale, Jan 04 2017
  

       //I am beginning to suspect that I actually know much less about polarization than I thought I did.//   

       The explainations I have seen, heard or read don't make 100% sense to me. I suspect that either a: they don't know everything and it falls into that chunk of physics that they can describe very well, and make useful things using the descriptions but.... b: its almightily complex stuff and we're in the: "look, 2 electrons in the first little planet orbit, 8 in the next one, and... no, don't ask why..." area of partial ignorance.   

       The way I understand it is that there are minerals through which light travels at different speeds depending upon what angle light hits it, because of crystals and things we have a fast axis and a slow axis through the mineral. I'm totally OK with that. Two photons, one perfectly aligned with the "fast" axis one 5 degrees off. Second one comes out slightly after the first, I am perfectly happy with that. You have two photons describing two points of a helix 5 degrees apart, the pitch of the helix dependent upon the relative delay introduced by the material. This is where I get confused. If I hit the material with light PERFECTLY polarized in the vertical plane, how can any rotation be induced? Each photon will travel through with the same speed. I understand that creating perfectly polarized might be difficult/impossible, but does that mean my circularly polarized helix is actually a messy thing with tremendous differences in relative light energy dependent on the degrees off-plane? Come to think of it, I'm not sure how a single photon gets refracted by a prism, unless different parts of the same oscillation can have different speeds... I'm now more confused than I was before.
bs0u0155, Jan 04 2017
  

       At the subatomic level, nothing describes reality because all our reference concepts are so 'macro'. Any description we use is just a model ("It's only a model...") which we use because it has some prescriptive power in a narrow range of applications. So, we might use the 'particle' model of an electron one day, and then the next day, for another purpose, use the 'wave' model of the electron. That's fine, as long as we recognise these are just models, which we use because they give us some words to talk about things with.
hippo, Jan 04 2017
  

       //Do circular polarisers come in clockwise and anti-clockwise variants?//   

       Also, should there be 4 kinds of photon torpedoes ?   

       What still gets me is that since light travels at the speed of causality, light doesn't experience time. A photon literally connects e.g. two stars. Photons perpetually link all space from their own point of reference, like they haven't progressed since the origin point of the big bang.
bigsleep, Jan 04 2017
  
      
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