MIT Student Gets Artistic With LED Art 163
Gibbs-Duhem writes "An MIT graduate student has up a page showcasing a standout art project. He's designed custom LED light fixtures which are seven times brighter than the closest similar commercial models, and include colors which can't be reproduced by a normal RGB cluster (including two ridiculously bright UV LEDs). The result: some beautiful mixed media artwork. The author's goal is to eventually publish a guide to make getting into creating such artwork more accessible to the general public. The site includes lots of great photos and a movie of the art in action. It also has in depth descriptions of the theory involved in this relatively new form of art, an explanation of how the paints were chosen, and an in depth technical discussion of how such lights are designed with schematics and board layouts for those who might wish to build their own lights."
Re:Don't forget to wear sunglasses. (Score:4, Insightful)
Worst. Explanation. Evar. (Score:4, Insightful)
The first step of the project was to understand the underlying physics behind LED based artwork. Fundamentally, the eyes are a very odd sensing system. The ears do a frequency based analysis of incoming pressure waves, and report all of the dominant frequencies to the brain for interpretation --- if we hear two frequencies of different pitches, they sound distinct. This isn't quite as true when you talk about harmonics of sounds, as they will start to affect the timbre instead of sounding as a distinct pitch, but the basic idea is that we can pick out independent sounds with different pitches fairly easily.
The eyes, on the other hand, do spatial and frequency-based sensing; however, they throw away much of the information about the specific frequencies detected. For instance, if you look at any particular spot, you will see a single color -- not a spectral map of the complete visible spectrum coming from that point. This is great for the purposes of vision; it would be rather difficult, I think, to walk around while receiving that much information. However, this means that the eye behaves very strangely in the presence of multiple colors from the same location.
The classical example of this effect is the color wheel. You mix red paint and green light, you get what appears to be yellow light. But how is this possible? If yellow is a frequency of light, how does mixing red (620nm) and green (530nm) produce yellow (590nm) light? There is certainly no physical process that does this sort of mixing in general.
In fact, the idea that red and green combine to form yellow is a trick of the mind only. You may think you're seeing yellow light, but the fact is that you are seeing independent red and green light, and your brain is converting that information into the appearance of yellow! Very strange. So, this can explain how a RGB cluster of LEDs can produce most colors of light -- they aren't actually producing those other frequencies of light; instead they are tricking the eyes into thinking that they are producing those other frequencies of light. This trick is summed up in the Chromaticity Diagram (pulled from wikipedia). On this diagram, pure frequencies are displayed along the outer border from 460 to 700nm. As you mix two colors together, you draw a line between their positions on the border, and the ratio of the two tells you the position in the diagram that your apparent color lies. For example, if you combine 520nm green light with 620nm red light in a 50-50 ratio, you will have what appears to be yellow light. Likewise, if you have 620nm red light and 490nm cyan light in a 50-50 ratio, you will have what appears to be approximately white light.
It would be sufficient to say this:
Human eyes' colored light sensors cover wide ranges of wavelengths with maximums at red, white and blue, so they can easily see colors of mixed paints (also wide ranges of wavelengths with multiple maximums) and have those colors imitated by LED screens and lights (three very NARROW ranges of frequencies near the maximums of eye sensors' sensitivity) however mixing the two (light from three narrow-band sources is reflected by wide-band paint, then seen by three types of wide-band sensors) produces distorted results because paint's reflectivity of wavelengths outside the lights' narrow bands does not contribute to the impression.
A paint with one of the narrow maximums at, say, cyan, will appear the same as paint without such a maximum if illuminated by a LED light that produces nothing in cyan range where the maximum is present. It's important to mention that in a photo taken under natural light and displayed on a LED screen, paints' colors will appear perfectly normal. This happens because light and camera's sensors cover approximately the same ranges as human eyes' sensors, so for the area covered with paint that has cyan maximum, screen would produce more green and blue light to imitate the impression on eye's green and blue sensors.
His solution is to:
1. Add more narrow-band sources so they cover more of the spectrum.
2. Use paint that mostly reflects the same colors as light sources produce, so it does not produce drastically different results under natural/incandescent/fluorescent and LED light.
3. Use ultraviolet LEDs and fluorescent paints to produce light on wavelengths that do not appear in the ranges produced by the light sources.
What is perfectly reasonable as long as the painter sees painting and lighting as two parts of the artwork, as opposed to usually accepted model of painting with the assumption that painting will be viewed under natural or incandescent light. But $deity, the explanation was beyond horrible.
Their clean web page needs no apology (Score:5, Insightful)
No apologies needed. I wish all web pages were as clean as yours, instead of covered in irrelevant decor, side panels and advertising that just obscures the message and makes loading times 10 times as long as they should be.
Google's minimalist search page stands almost alone in retaining functional sanity among major websites. Don't feel bad emulating that frugality.
Re:damnit (Score:5, Insightful)
Not even faux news said she tried to walk through a "security checkpoint" - all she did was ask a question of the person at the info desk.
The person at the info desk - NOT EVEN VAGUELY SECURITY PERSONNEL - asked her what the LEDS were, she said "art" and then continued about her business.
The blame lies solely on stupid CYA security policies that require a "response no matter what" -- that's escalation without application of rational thinking. You've got one dumb cluck of a info-desk clerk, who probably doesn't even have a high school diploma, causing a major incident that could have been easily avoided if anyone at any step of the way had applied a degree of critical thought to the issue. What's next? Exvacutation because someone dreams about a bomb? [guardian.co.uk]
Don't think for a minute that any of this anti-terrorism "security" is about protecting anyone from actual threats. They might as well name them the Department of the CYA because their sole purpose is to protect the asses of the people in charge. If they react completely out of proportion to any perceived threat, then when an actual threat slips through they can point at all of their over-the-top reactions in the past as proof of 'diligence' thus insuring their asses are well covered, and may even get increased funding...
This institutionalized cowardice is destroying our country, it has got to stop or we will never be able to maintain our status as the largest superpower.
PWM dimming of RGB LED's is patented (Score:2, Insightful)
I hope this student got a license.
Re:Don't forget to wear sunglasses. (Score:2, Insightful)
P.S. Be really sure you don't forget to wear sunglasses when you bring one of these into work.