Believe it or not, what you see here is the smallest inkjet color photo ever printed. It is so small that it is invisible to the naked eye. You'll need a microscope to see it.
Η inkjet printed photo shows clownfish circling around one sea anemone which is also their home. Photo produced by researchers on ETH of Zurich.
Using a groundbreaking technology called 3D NanoDrip invented at the university, the team was able to print the photo of 80 × 115 micrometers (micrometers = millimeters of millimeters) or about 0,0092 square millimeters.
The above number is equivalent to the cross-section of a human hair, or if you want a pixel in a super-high resolution Retina screen.
This scale was achieved thanks to something called quantum dots (QDs), or nanoparticles that can emit light of a specific Colourof The resulting extremely small photo has been officially designated as the world's "smallest inkjet printed color image" according to Guinness World Records.