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This is not how color vision works. It works by differential analysis between sections of the eye, by some very fascinating positive and negative feedback loops in the processing cells of the retina. Unfortunately, these retinal electrodes are so large, and the current spread so much, that the signals *swamp* all the local processing cells. Also unfortunately, if you make the electrodes smaller, you increase the resistance and the current density, until you start electrolyzing the vitreous humor trying to localize signals.

We won't get good visual prostheses until and unless we can get the electrodes onto the optic nerve itself, with far more resolution. For examples of approaches that could conceivably work, take a good look at David Edell's work, at http://www.mrs.org/s_mrs/sec_subscribe.asp?CID=2603&DID=110240&action=detail. But his work would involve avoiding the retina and stimulating the optic nerver: so far, it's really only suitable for muscle nerves.

The source material for this LED is Gallium Nitride(GaN). Its quite a revolutionary semiconductor material developed first by Shuji Nakamura in the 90s at Nichia Corporation, Japan.
It has a multitude of applications in different fields - optoelectronics, HF microwave communications and anti-radiation hardening for space vehicles.

These LEDs are very efficient in the sense that they consume less power and have more lumen output. And they die out gradually, unlike traditonal sources of lights like tubes/bulbs which will immediately fuse off. Which explains why they are robust alternatives for street lights, traffic signals, etc. They need less power, less maintainance and due to their solid state nature are quite tough materials.

Lot of research has been conducted on them. Here are couple of leading centres for GaN research -
UCSB - http://my.ece.ucsb.edu/mishra/studygane.htm
Cambridge(UK) - http://www.msm.cam.ac.uk/GaN/

There is an online journal of Nitride Semiconductor research not updated much now, but very useful -
http://nsr.mij.mrs.org/

Check it out.

Many traffic light signals use these LEDs already across the world nowadays for less power consumption. Watch out for few in your city.
I remember back in my college days that it was already being touted as a replacement for the century+ old incandescent bulb. Buzz and hype I guess but still with a lot of substance.

Cheers!

don't go wasting the charities money

not to nitpick, but not all non-profits are charities, and some non-profits have a lot of money to spend. case in point

From MRS itself.

What about the people that informed him which application to fill out? I mean, it's not common knowledge that for presenting a workshop at a conference you have to fill in visa application 157-12399-b. Oh, he's from Germany and earns more than 25k per year? then it's 157-12399-b'

He is being treated like anyone else. A few years back, I was flying to Boston from Canada to attend the Materials Research Society conference, where I would be giving an invited talk.

US Customs & Immigration asked me where I was from, where I was going, and what would I be doing there. I answered truthfully. They then asked me how much I was being paid to give my presentation. I laughed and truthfully said "Nothing. I have to pay to attend the conference."

They said, "Enjoy your stay", and that was it.

Despite being a white Canadian citizen, born in Canada, I am not entitled to work in the USA without the appropriate visa, even though engineers are covered by the North American Free Trade Agreement, and can get a TN visa at will. To get a TN visa you need to show that you are a citizen, that you have a job offer for one of the professions covered under NAFTA, and that you are a member of that profession. Very easy, no waiting, but you still have to get the visa.

It may come as a surprise for EU citizens who are used to travelling & working throughout the EU without a visa, let alone a passport, that there are formalities go though. Not that long ago, you needed all these things in the EU.

Now, it's much easier to claim a big conspiracy theory...

http://www.mrs.org/s_mrs/sec_subscribe.asp?CID=255 3&DID=117686&action=detail">You can buy the better ones in Colorado.
Of course, you will have to compete with Uncle Sam, specifically, NSA and CIA.

...note that shielding can sometimes cause a net increase in dangerous radiation, as high-energy cosmic rays that would just pass through a person impact the shielding and bombard the shielded thing (like a person) with a series of lower energy radiations, which may total a lower energy overall then the cosmic ray but have a much greater effect on the person.

Also, according to a paper in materials science research titled, Cosmic-Ray Neutrons on the Ground and in the Atmosphere And a number of other papers by the same author, the measurements show that the cosmic contribution to background dose rate increases as the strength of the magnetic field decreases.

The error in logic with your argument is that the magnetic field deflects particles before they reach the atmosphere and interact. Once they reach the atmosphere, they interact with the atmosphere (not the magnetic field) to generate the "more dangerous radiation." as you call it. That said, I'm not entirely sure that this radiation is any more or less dangerous. While it is true that the quality factor is lower (what you multiply the energy deposion by to get the increased quantity that is proportional to increased probability of cancer), the energy deposition can be higher (this is true for photons, but not electrons, and I just don't know for protons and higher Z charged particles with kinetic energies in the GeV range).

Anyone remember researchers using inkjets to fabricate small components?

As I recall, research in this area was hindered because people were forced to use the older, lower resolution printers since the newer printers had chipped cartridges making it hard to refill them.

See this report of the Material Research Society for the kind of research that will explode once high res printers can be used.

Anyone remember researchers using inkjets to fabricate small components?

As I recall, research in this area was hindered because people were forced to use the older, lower resolution printers since the newer printers had chipped cartridges making it hard to refill them.

See this report of the Material Research Society for the kind of research that will explode once high res printers can be used.

is perfectly possable.

RF shielding basically consists of a Farady cage around the compnent. To do this in a transparent case will require the use of a transparent conductive material.

These exist.

For example, the most common in indium tin oxide, although alternatives exists, such as indium gallium nitrate

In this particular case, the requirement for the anneal post-deposition for indium tin oxide could be a problem, assuming the case is made of a polymer. Additionally, you'd need an outer layer, the conductive Faraday cage, and then an inner layer, to protect the conductive layer.

Still, it is 100% possable. And expensive.