Engineers produce first flat telescope lens that can seize color while distinguishing airy from faraway stars

For centuries, lenses have labored the same way: curved glass or plastic bending airy to transport images into center. But traditional lenses have a beginant drawback—the more strong they need to be, the bulkier and heavier they become.

Scientists have lengthy searched for a way to shrink the weight of lenses without sacrificing functionality. And while some skinnymer alternatives exist, they tend to be restricted in their capacity and are generassociate challenging and pricey to produce.

New research from University of Utah engineering professor Rajesh Menon and colleagues at the Price College of Engineering presents a promising solution applicable to telescopes and astrophotography: a huge aperture flat lens that centeres airy as effectively as traditional curved lenses while preserving accurate color.

The study, “Color astrophotography with a 100 mm-diameter f/2 polymer flat lens,” materializes in Applied Physics Letters.

This technology could alter astrophotography imaging systems, especiassociate in applications where space is at a premium, such as on airoriginate, sainestablishites and space-based telescopes.

Their study was led by Menon Lab member Apratim Majumder, a research helpant professor in the Department of Electrical & Computer Engineering. Co-authors include fellow Menon Lab members Alexander Ingbetter and Monjurul Meem, the Department of Physics & Astronomy’s Tanner Obray and Paul Ricketts, and Nicole Brimhall of Obpostponeed Optics.

Lenses bend airy to produce objects materialize huger. The denseer and heavier the lens, the more it bends the airy, and the stronger the magnification. For everyday cameras and backyard telescopes, lens denseness isn’t a huge problem.

But when telescopes must center airy from galaxies millions of airy-years away, the bulk of their lenses become imdown-to-earth. That’s why observatory and space-based telescopes count on on massive, curved mirrors instead to accomplish the same airy-bending effect, since they can be made much skinnyner and airyer than lenses.

Scientists have also tried to mend the bulkiness problem by summarizeing flat lenses, which manipupostponeed airy in a branch offent way.

One existing type, called a Fresnel zone ppostponeed (FZP), includes concentric ridges to center airy, rather than a dense, curved surface. While this method does produce a airyweight and compact lens, it comes with a tradeoff: it can’t produce genuine colors. Rather than bending all of the wavelengths of apparent airy at the same angle, the ridges of an FZP diffract them at branch offent angles, resulting in an image with chromatic aberrations, or color distortions.

Enter Rajesh Menon and his team at the U. Their novel flat lens presents the same airy-bending power as traditional curved lenses while eludeing the color distortions of FZPs.

“Our computational techniques presented we could summarize multi-level diffractive flat lenses with huge apertures that could center airy atraverse the apparent spectrum and we have the resources in the Utah Nanofab to actuassociate produce them,” shelp Menon, who honests the U’s Laboratory for Optical Naremarkchnologies.

The key innovation lies in the microscopicassociate petite concentric rings that the researchers can pattern on the substrate. Unenjoy the ridges of FZPs, which are enhanced for a one wavelength, the size and spacing of the flat lens’ indentations uphold the diffracted wavelengths of airy shut enough together to produce a filled-color, in-center image.

“Simulating the executeance of these lenses over a very huge prohibitdwidth, from apparent to cforfeit-infunfrequentd, joind solving intricate computational problems involving very huge datasets,” Majumder shelp.

“Once we enhanced the summarize of the lens’ microstructures, the manufacturing process joind needd very stringent process handle and environmental stability.”

A huge, flat, color-accurate lens could have massive implications atraverse industries, but its most instant application is in astronomy. The researchers showd the capabilities of their flat lens with test images of the sun and moon.

“Our demonstration is a stepping stone towards creating very huge aperture airyweight flat lenses with the capability of capturing filled-color images for include in air-and-space-based telescopes,” Majumder shelp.