They develop the microcamera that will be used by nanorobots

  Incredible micro cameras for nanorobot

Nanorobotics, as is the case with graphene, is a term that has been on the lips of researchers for years, but has not yet been exploited on an industrial production scale. Everyone is aware of its potential, but the technical hurdles are still there. Luckily, at a steady pace, the investigation advances. The latest invention that would allow the world's tiniest robots to take a giant leap is a camera that is barely the size of a grain of salt.

Imagine for a moment that, instead of using a bulky CT scan or an intrusive endoscopy, an almost invisible robot would suffice to inspect your arteries or the most inaccessible corners of your heart. It's the kind of applications that could be enabled by the new camera designed by scientists at Princeton University in the US It's the size of a grain of salt and works in a radically different way than traditional lenses.

The inventors of this new device claim that the image quality is similar to that of a camera 500,000 times larger. To achieve this they have had to reinvent the concept of the camera and resort to a combination of hardware and software based on neural networks. This is how they have achieved it.

For one thing, your camera looks more like a microchip than a lens. In fact, the basic material is silicon nitride, used in the production of semiconductors. Thanks to him, instead of using a lens to bend light rays, they have introduced 1.6 million cylinders in a space of less than half a millimeter. Each of these cylinders is a different size to emulate the effect of a lens. Thus, they operate as optical antennas. In scientific jargon, this set is known as a "metasurface".

To understand what a metasurface is, it is necessary to first talk about metamaterials. These are engineered micro- or nanoscale structures that interact with light and other types of energy in ways unknown in the natural world. One of them is negative refraction, a phenomenon that opens the door to results as disconcerting as invisibility or superlenses of an unprecedented capacity, such as the Princeton University camera. Thus, metasurfaces are films that take advantage of the qualities of metamaterials.

However, the physical part is only one element of the equation. The second achievement of the developers has been to create a design that processes the signals through a neural network. This processing system achieves sharp images in natural light conditions.

Until now, metasurface-based devices have only achieved satisfactory results in the laboratory and using lasers or controlled environments. Additionally, the resulting images lacked depth of field or were unable to display the visible light spectrum and RGB color gamut.

Thanks to the fusion of metasurfaces and neural networks, images equivalent to those of a camera with six lenses and a size half a million times larger are obtained, as pointed out at the beginning of this article. The researchers note that while the metasurface approach has been tried before, it is the first time the two techniques have been combined.