Not even squinting will help you see this image without the help of a microscope. This is the smallest inkjet-printed colour image ever produced, and it’s the same size as a single pixel on a Retina display.
Created by researchers from ETH Zurich University and a startup company called Scrona, the image was made using a technique they call 3D NanoDrip printing. The process uses what are known as quantum-dots—nanoparticles that emit light of a very specific color—to build up the image. The inkjet printing process lays down a series of red, green and blue quantum dot layers, at a resolution of 25,000 dots per inch. That means that each pixel sits just 500 nanometers from the next.
The resulting picture of clown fish is surprisingly vibrant, given that it measures just 80 microns by 115 microns, covering an area of just 0.000014 square inches. And yep, that is about the same size as a Retina display pixel.