microspheres

The token is multiple translucent microspheres pressed together and its authenticity verified by shining a laser on it from different directions and capturing the output.

The microspheres don't burn up because they don't strongly absorb (i.e., they're mostly transparent) at the laser's frequency.

It seems this is a composite of (glass,ceramic,etc) microspheres in a resin matrix.

How much does fabricating the microspheres and then the pebbles cost?

These are linked directly in the OP article: Even at low concentrations (1–30 µg/ml), photoaged microspheres at 1 and 5 µm in diameter exerted more pronounced biological responses in the A549 cells than was caused by pristine microspheres.

Polystyrene microspheres reduced monolayer barrier integrity and slowed regrowth in a wound healing assay in a manner dependent on dose, photoaging, and size of the microsphere.

Instead of using standard vaccine practices (a dead/damaged/live version of the virus) to train your immune system, we are using these synthetic entities called microspheres.

Yeah, the microspheres have the property of being very retroreflective (shine headlamp light directly back toward a driver efficiently) and so get used in lots of automotive visibility scenarios.

The focusing lens additionally has a electromagnetically controlled suspension system for adjusting the focus, so in theory you should be able to achieve z positioning of the microspheres as well.

Looks like the authors of the first paper I read on it (glass microspheres in silver-backed clear plastic film) are finally starting to commercialize it too...

I looked road markings up earlier because it was also my first guess, but everything I've seen indicates they just use plain glass microspheres in reflective paint and such.

Latex microspheres were produced on the space shuttle and sold as calibration sources for microscopes.[1] Because microscope calibration needs literally microscopic amounts of these microsphere, per unit mass the product was very valuable.

In their FAQ they mention the use of microspheres and state that "in a petri dish we have been able to induce dendritic cells to take up the microspheres through a process called phagocytosis".

"exfoliating microspheres" and then start requiring washing machine OEMs to put replaceable filters on the discharge.

"exfoliating microspheres" Already done in the UK and US.

>>there is a concrete like “synthetic foam” The word you are looking for is "syntactic foam", which is an epoxy or other material typically with embedded hollow glass microspheres.