Scientists have created an artificial eye that could potentially revolutionize today’s camera technology.
According to reports, researchers from the Harvard John A. Paulson School of Engineering and Applied Sciences (SEAS) have developed an artificial eye by utilizing adaptive metalens technology and synthetic muscles.
The flat, electronically controlled metalens is described as having control of the three major contributors to blurry images: astigmatism, focus, and image shift.
“This research combines breakthroughs in artificial muscle technology with metalens technology to create a tuneable metalens that can change its focus in real time, just like the human eye,” Alan She, first author of the study which was published in the journal Science Advances, said.
“We go one step further to build the capability of dynamically correcting for aberrations such as astigmatism and image shift, which the human eye cannot naturally do.”
Federico Capasso, the senior author of the study and Robert L. Wallace, Professor of Applied Physics at SEAS, said that their work “demonstrates the feasibility of embedded optical zoom and autofocus for a wide range of applications including cell phone cameras, eyeglasses, and virtual and augmented reality hardware.”
The artificial eye could also be used in improving the capabilities of electronic optical microscopes while simultaneously correcting many anomalies in the image.Researchers have reportedly created an artificial eye that could revolutionize today's camera and optical technologies. #OpticsClick To Tweet
How The Artificial Eye Was Made
For the researchers to build the artificial eye, they first had to scale-up the metalens.
Usually, metalenses are around the size of a single piece of glitter. Generally, these metalenses use pattern nanostructures to focus light and remove spherical aberrations in the image. This works as the nanostructures used are smaller than the wavelength of light.
“Because the nanostructures are so small, the density of information in each lens is incredibly high,” She explained. “If you go from a 100 micron-sized lens to a centimeter-sized lens, you will have increased the information required to describe the lens by ten thousand. Whenever we tried to scale-up the lens, the file size of the design alone would balloon up to gigabytes or even terabytes.”
To counteract this scaling issue, the researchers developed a new algorithm to shrink the metalens’ file size enough to make it compatible with the current technology used in fabricating integrated circuits.
In a separate study published in the journal Optics Express, the researchers demonstrated how they fabricated the metalenses up to a centimeter or more in diameter.
“This research provides the possibility of unifying two industries: semiconductor manufacturing and lens-making, whereby the same technology used to make computer chips will be used to make metasurface-based optical components, such as lenses,” Capasso went on to say.
After shrinking the metalens, the researchers combined it with an artificial muscle without jeopardizing its capability to focus light.
To mimic the human eye’s ability to focus light through the ciliary muscle, the researchers chose a thin, transparent “dielectric elastomer” to attach to the lens of the artificial eye. By applying voltage, the position of the nanopillars on the surface of the lens can be controlled as it shifts.
Controlling the position of the nanopillars and the total displacement of the structures is significant in fine-tuning the metalens.
The researchers were also able to demonstrate how the lens can focus, control aberrations due to astigmatism, and perform image shift all at once.
The artificial eye is reported to have a thickness of only 30 microns.
“All optical systems with multiple components – from cameras to microscopes and telescopes – have slight misalignments or mechanical stresses on their components, depending on the way they were built and their current environment, that will always cause small amounts of astigmatism and other aberrations, which could be corrected by an adaptive optical element,” She explained.
“Because the adaptive metalens is flat, you can correct those aberrations and integrate different optical capabilities onto a single plane of control.”
Right now, the researchers are currently working on improving the functionality of the artificial eye while decreasing the amount of voltage needed to control it.