Great idea! reminds me of another project that used IR leds behind a blank canvas in an art gallery. When people go to take a picture of "what junk passes for art these days" the secret "painting" is revealed. This is really cool either way, I was just thinking merging the two would be interresting.
Novel use of a LED array. Nice that Allied provided part numbers for the bits they do supply. But it would be useful if the supplier of the non-allied parts were also part of the article. Especially considering that the LED array is fundamental to the gadget.
You know what would be fun? Hang a weight on a rachet (like a pendulum grandfather clock) to spin a motor/generator to provide the electrical energy for this circuit. Lose the AC mains line cord running up the wall.
Focus on Fundamentals consists of 45-minute on-line classes that cover a host of technologies.
You learn without leaving the comfort of your desk. All classes are taught by subject-matter experts and all are archived.
So if you can't attend live, attend at your convenience.