Projecting on a moving particle isn't quite new. A quick search reveal that there have been projections on falling water droplets since at least 2010. There are also plenty of stroboscopic experiments on water drops which make them fall upwards.
I think having a controllable particle is a nice-feat but probably is overkill for 3D displays, you only need to know where the particles are so you can use them as a screen.
Although the 2010 paper project on layers of waterfalls, it's easy to imagine a 2d water droplet grid where you watch the droplets form and drop with a hi-speed camera and with a video projector you then project the right pixel at the right time so that light ray intersect water droplet. You can even try this today at home with a shower jet and a pico projector, and see beautiful clouds of red green blue rays.
It's probably a fun engineering project to get the right combination of liquid properties, size of droplets, frequencies, video bandwidth to obtain stunning results.
I think having a controllable particle is a nice-feat but probably is overkill for 3D displays, you only need to know where the particles are so you can use them as a screen.
Although the 2010 paper project on layers of waterfalls, it's easy to imagine a 2d water droplet grid where you watch the droplets form and drop with a hi-speed camera and with a video projector you then project the right pixel at the right time so that light ray intersect water droplet. You can even try this today at home with a shower jet and a pico projector, and see beautiful clouds of red green blue rays.
It's probably a fun engineering project to get the right combination of liquid properties, size of droplets, frequencies, video bandwidth to obtain stunning results.