Miniature Colour Camera via Flat Hybrid Meta-Optics: a small camera that captures high quality images
Researchers Karén Eguiazarian, Vladimir Katkovnik, Seyyed Reza Miri Rostami and Igor Shevkunov from Tampere University have been developing hybrid optics that are more than a hundred times smaller than traditional compound lenses. The study has been done together with researchers Samuel Pinilla from the Science and Technology Facilities Council in Harwell, UK, and Arka Majumdar and Johannes E. Fröch from the University of Washington in Seattle.
“Modern cameras are optimised to produce high-quality images. They are typically composed of many lenses to compensate geometric and chromatic aberrations. However, that increases the size and weight of the camera. In the study, our aim was to make cameras smaller and lighter while maintaining a high image quality,” Eguiazarian describes.
Extensive research on this topic has recently been made in optics and photonics research. The race for miniature colour cameras, which employ flat diffractive meta-optics instead of conventional refractive lenses, has rapidly developed the end-to-end design framework that is using modern neural networks.
High-quality imaging with only two optical elements
Although a large body of work has shown the potential of this technology, the reported performance is still limited due to the fundamental restrictions of diffractive meta-optics, the mismatch of simulated and resultant experimental point spread functions, and calibration errors.
“A solution to this conundrum is computational imaging, where a digital backend augments the deficiencies of the optical components and improves image quality. This has thus become a multidisciplinary research field at the intersection of optics, mathematics, and digital image processing,” Eguiazarian says.
In the study, a novel optics design methodology is proposed to solve these limitations and demonstrate a miniature colour camera via flat hybrid meta-optics (lens + meta surface). The resulting camera achieves the high quality of full-colour imaging for a 5 mm aperture optics with a focal length of 5 mm.
This means that high-quality imaging is now available with only two optical elements which in turn is seen in the dimensions of the miniature camera.
“The superior quality of the images captured by the hybrid meta-optical camera is demonstrated as compared to the compound multi-lens optics of commercial cameras. Despite its miniature size, images produced by our camera are of superior quality,” Eguiazarian points out.
One of the lifelong outcomes of the project is the contribution to resource-wise sustainable development. Since the approach of the study requires fewer lenses, the results use significantly less glass or plastics.
karen.eguiazarian [at] tuni.fi
+35840 8415 663