Even Picasso did (purportedly) the first light paintings (manually of course) back in 1949, and I've been doing manual painting with various flashlights, LED lights, fire, sparklers, etc. since at least 2005, during which time I've seen many projects. You might want to check Vimeo and Youtube, there are tons of old artworks using LED strips, etc. One of the first inventions I saw was the Light Graffiti videos from LichtFaktor (https://www.lichtfaktor.com)... although their earlier stuff was all done manually as well.
In the end though it doesn't matter that you aren't original, it matters that you did it and possibly added something new (spending time thinking about resolution, color quality, etc).
Oh, yes, light painting is probably as old as the camera, but I think "painting" photorealistic images with a strip is different enough to count as an original idea.
I'm not very fussed about being the first anyway, it was just fun to think that I created something nobody else had before. Fun while it lasted, anyway :P
This has actually been being done for a decade at least, you can find instructions online for it, I had the same experience with just about every idea I had when I first joined my university maker space, not only had all my idea been done, half of them had been done specifically _by that makerspace_ just when they were picking fun projects to do off the internet.
The point is to make stuff and enjoy it, you're still an inventor. And the things you _do_ with your projects are half the fun, your photos are really fun and I wouldn't have thought of a lot of them.
Agreed, in the end I do it because it feels great to make things. I really love soldering and routing PCBs, for some reason, I should make more of those...
But I'm really glad you didn't know about it and made yours :) since you really put a lot of thought into the details about color reproduction, resolution and diffusion. It's a very fun thing to play with and anyone wanting to build something similar will now be able to find great resource of info and implementation details on your site.
