A friend and I are entering a video into the Optical Society’s Optics in a Minute video contest. We’re doing our video on photonic crystal fibres, which are allowing researchers to explore new ways of transmitting light for things like telecommunications and medical procedures.
Traditional optical fibres, that employ total internal reflection of light to carry information for things like the internet, can’t carry high powered laser light, because they would either melt, or distort the light – not great for accurately carrying data.
But unlike the solid glass traditional fibres, photonic crystal fibres are made up of a long hollow crystal of silica, so they carry the light in a different way (Fig 1). The sides of the crystal will allow certain wavelengths of light through but not others, due to an effect known as the photonic bandgap. And you can choose a crystal that reflects only the band of wavelengths you’re after (Fig 2).
This means that we can now guide powerful lasers within fibres that don’t melt and don’t distort the light.
Stay tuned for the video – we’ll put it up on youtube and I’ll post it here…
Apologies for my being so rubbish at posting this week. To make up for it, a short and sweet quick-fire fact for each of the days I missed:
Tuesday: Lichens are a symbiosis between a fungus and algae or a fungus and cyanobacteria. ‘Lichen’ is not a taxonomic group, but a way of living.
Wednesday: A study has shown that viagra can help hamsters overcome jetlag. It’s yet to be seen if the same would be true for humans…
Thursday: Water is in fact blue, not just drawn that way in kids’ drawings, because the water molecules absorb red light and the remaining light looks blue.
Friday: Breathing helium doesn’t actually make the pitch of your voice higher, but changes the resonant frequency of your throat and mouth, amplifying the higher frequencies coming from your vocal cords and making your voice sound squeaky.
Today’s factlet on lasers is rather short and sweet, but if you want to find out a bit more, have a watch of the video below.
When you see the beam coming out of a laser pointer, or any other laser for that matter, whether it’s in a DVD player or a supermarket scanner, you’re only seeing 1% of the light that is actually being produced inside the laser itself.
This Naked Science Scrapbook explains more about lasers, how we produce them and what we use them for – enjoy!