In many ways, the human eye is nothing like a digital camera. Our eyes don’t have a fixed frame rate or resolution; there’s no consistent color reproduction, and we have literal, sizable blind spots. But, these optic inconsistencies — found in every biological eye — are the product of natural selection, and offer a number of benefits which scientists working in digital vision can take advantage of.
Case in point is a new type of 3D-printed lens created by researchers from the University of Stuttgart in Germany. Each lens is made from plastic and is no bigger than a grain of salt. But, their size is only one aspect of their cleverness. The real innovation here is that the lenses mimic the action of the “fovea,” a key physiological feature of the eyes of humans and eagles, that allows for for speedier image processing.
Fovea is latin for “pit” or “pitfall,” and the thing itself looks like a small hollow in the back of your retina. It’s home to a dense concentration of photoreceptor cells, and acts as a focal point for vision. If you hold out your hands in front of you at arms’ length, the fovea covers an area roughly equivalent to both your thumbnails, or around two degrees of your total field of view. (That comparison this Vsauce video.) This creates a central point in our vision that’s high-resolution, surrounded by a lower-resolution whole. This allows us to focus our optic power where it’s needed, that is to say: where we’re looking. Humans see like this, and eagles do as well (they have a particularly deep fovea that offers pin-sharp vision).
By re-creating this setup in tiny lenses using 3D-printed plastic, scientists hope they’ll be able to make cameras that can process images more quickly and efficiently. Plus, as the individual lenses are so small, they can be used for technology like tiny flying drones (robot bees!) or surgical tools that need to operate inside the body. There are some drawbacks to the lenses, including the fact they take hours to 3D print, but these problems will hopefully be solved by mass production. A full study describing the technology can be read in the journal Science Advances.