For centuries, cameras and telescopes have relied on curved glass or plastic lenses to bend light and bring images into focus.
However, the more powerful these lenses need to be, the bigger, heavier, and bulkier they become.
This has been a major challenge, especially in space-based telescopes and aircraft where size and weight matter.
Now, researchers at the University of Utah have created an innovative flat lens that can capture sharp, full-color images while remaining lightweight and compact.
This breakthrough could revolutionize telescopes, astrophotography, and even imaging systems used in space exploration.
A new type of lens
Traditional lenses magnify objects by bending light through their thick, curved surfaces.
While this works well for everyday cameras and small telescopes, it becomes a problem when capturing images of distant galaxies.
Large observatory and space telescopes often use massive, curved mirrors instead of lenses to avoid the weight issue.
Scientists have tried to solve this problem by developing flat lenses, but most existing versions struggle with color accuracy. One common type, called a Fresnel zone plate (FZP), uses tiny ridges to focus light. While this makes the lens thinner and lighter, it also distorts colors, making images less accurate.
Professor Rajesh Menon and his team at the University of Utah’s Price College of Engineering have developed a new flat lens that overcomes these limitations.
Their research, published in Applied Physics Letters, describes how this lens can focus light just as effectively as traditional curved lenses while preserving true colors.
“Our computational techniques suggested we could design multi-level diffractive flat lenses with large apertures that focus light across the visible spectrum,” Menon explained. “And we have the resources in the Utah Nanofab to actually make them.”
The secret lies in the microscopic rings on the lens’ surface. Unlike the ridges in FZPs, which work best for a single wavelength of light, the new lens has carefully designed indentations that keep different wavelengths close together, allowing it to produce sharp, full-color images.
A big step for astronomy
The researchers tested their new lens by capturing detailed images of the sun and moon. The results prove that this technology has huge potential for improving astrophotography, space telescopes, and imaging systems on satellites and aircraft.
“This is a stepping stone towards creating very large, lightweight, flat lenses capable of capturing full-color images for air-and-space-based telescopes,” said researcher Apratim Majumder.
With this breakthrough, telescopes could become smaller and lighter while still delivering high-quality images, making it easier to explore the universe. The discovery marks an exciting step forward in optical technology and could change the way we see the stars.
