Credit: David Baillot/UC San Diego Jacobs School of Engineering
A new phosphor material for white LEDs that is inexpensive and easy to make has been developed by researchers at the University of California San Diego, USA. The team used data mining and computational tools to discover the material, and have built prototype white LED light bulbs using it. The prototypes exhibit better colour quality than commercial LEDs currently on the market.
The phosphors used in commercial white LEDs have disadvantages. Many are made of rare-earth elements, which are expensive, and some are difficult to manufacture. They also produce LEDs with poor colour quality. The new phosphor avoids these issues as it is made mostly of earth-abundant elements, can be made using industrial methods, and it produces LEDs that render colours more vividly and accurately.
Made of the elements strontium, lithium, aluminium, and oxygen (SLAO), the new phosphor was discovered using a systematic, high-throughput computational approach. The team used supercomputers to predict SLAO, which is the first known material made of these elements. Calculations also predicted this material would be stable and perform well as an LED phosphor.
The LEDs were evaluated using the Colour Rendering Index (CRI), a scale that rates from 0 to 100 how accurate colours appear under a light source. Many commercial LEDs have CRI values at around 80. LEDs made with the new phosphor yielded CRI values greater than 90.
Fabrickind, I'm revamping my old Vocaloid Magnet cosplay by adding lights into the ribbon/bow around the waist and into the butterfly shaped headphones to make them glow along with the ribbon around the mini top hat that goes with it. I've never worked with lights before. Would LED or EL lights be better? What's the best way to diffuse them?
With where you want to lights and the fact that you seem to want to edge things in lights, I’d go with EL wire.
EL wire is great for things where you need a thin, continuous line of light without the need to diffuse multiple spots, or where you need some (but not a lot) of flexibility. The drawbacks are that it isn’t as bright as LEDs in many cases (especially if you get the cheap wire), can be damaged easily if it is flexed too much or too far, and requires a large and somewhat noisy converter box to hide the batteries/convert between AC/DC that would need to be hidden somewhere.
I would put LEDs in the headphones themselves and find a way to hide the batteries, since this would be easier to diffuse through the colored plastic, and use EL wire to edge the ribbons and such. With LEDs, you really need them to be over a larger area and underneath something so that you can make an entire area glow, rather than something small like a bow.
Silicon dioxide nanoparticles resembling sand coated with a
high dielectric constant polymer.
Who is involved?
A team from Woodruff School of Mechanical Engineering at the
Georgia Institute of Technology, USA, led by Associate Professor Baratunde
What could it be used for?
The team claims the material acts as a thermal conductor for
electronic devices and LEDs with high heat fluxes, potentially conducting heat
at higher efficiencies than conventional materials.
What was the process?
The researchers previously used water to coat the
nanoparticles to turn the silicon dioxide nanoparticle bed into a conductor.
However, the water coating proved ineffective, forcing the researchers to
replace the water with ethylene glycol. This coating increased the heat
transfer by a factor of 20 to one watt per metre-kelvin, allowing the material
to dissipate heat at high efficiencies.
What are the next steps?
The team plans to investigate other polymeric materials that
can be adsorbed to the silicon dioxide nanoparticles to provide a more stable
coating with a longer lifespan than ethylene glycol. Further testing is needed
to ensure the long-term efficiency of the material. The team also needs to
confirm that there will be no harmful effects on the electronics being cooled.
To read the full research paper, High thermal conductivity in polaritonic SiO2 nanoparticle beds in Materials Horizons, visit rsc.li/2adlIhr
Hello! Do you have any suggestions for adding fairy lights into a costume? Especially any ideas about diffusing the light so it looks like a general glow rather than a point of light? Never worked with them before, and I’m not sure if diffusing can be accomplished. Thanks!
Diffusion comes from scattering the light. You can definitely diffuse the fairy lights but you’ll need to add something to them to cause the light to scatter. It also is a very small point of light, so it will be hard to diffuse across a large area, you may need a group of lights to create a larger area of diffused light.
Some ways to create the diffusion are to use a translucent piece of plastic or translucent fabric over the light. Some common methods are to use translucent plastic sheets in front of a light, putting lights within the hem of a garment or on a petticoat that is worn under a skirt, putting the lights in a clear plastic ball that has been scratched up with sand paper or in a ball of tulle.
These are the LEDs were are using the illuminated the inside of the companion cube base. They came with a controller allowing for many different colors and the ability to stobe them at various speeds. However we will be using them to represent the blue of the weight cube (and possibly the yellow of an activated weight cube) and the pink of the companion cube.
This LED strand is incompatable with being hooked up to the Raspberry Pi (and is much cheaper because of that) so it will be controlled through it’s own controller. Because the cube doesn’t change often, and because changing cube designs requires also changing the symbols, having the lights on their own control system doesn’t impact use.