March 21, 2025
How One Mathematician Solved a 2,000-Year-Old Camera Lens Problem

It’s a problem that has plagued photography since its creation: soft edges. No matter how high-quality the camera, math has dictated that the curve of optical lenses would always be slightly softer than the center. At least, that was the problem until Rafael G. González-Acuña, a doctoral student at Mexico’s Tecnológico de Monterrey, up and solved it.

The problem goes back thousands of years to the Greek mathematician Diocles. A (far less famous) contemporary of Aristotle, Diocles wrote a book titled Burning Mirrors. In that book, Diocles described what would become known as a “spherical aberration.”

To vastly simplify it, the problem is that as light rays fall on a lens, different rays don’t meet after the lens in a single focal point. Imperfections in the lens, even on the most high-end model, prevent total removal of the aberration.

Since Diocles brought up the problem, nobody in history has been able to find a good answer. And considering the massive uptick in camera ownership over the last two decades, that’s saying something.

But Héctor A. Chaparro-Romo, a doctoral student at the National Autonomous University of Mexico (UNAM), had a feeling that the problem could be solved. So he began working on a solution three years ago, and eventually invited González-Acuña to solve it with him.

“I remember one morning I was making myself a slice of bread with Nutella, when suddenly, I said out loud: Mothers! It is there!,” González-Acuña tells PetaPixel.

How did González-Acuña crack the aberration? By using an extremely complex mathematical formula, published in an article titled “General Formula for Bi-Aspheric Singlet Lens Design Free of Spherical Aberration,” in the journal Applied Optics. How complex? Well, it looks like this:

González-Acuña math formula optical lens

González-Acuña

González-Acuña’s mathematical formula for better lenses.

Yeah.

“In this equation we describe how the shape of the second aspherical surface of the given lens should be given a first surface, which is provided by the user, as well as the object-image distance,” González-Acuña tells PetaPixel. “The second surface is such that it corrects all the aberration generated by the first surface, and the spherical aberration is eliminated.”

Head spinning aside, González-Acuña’s formula has serious real-world potential. Beyond consumer needs, it could make for sharper lenses on scientific and medical equipment, from telescopes to microscopes.

Expert Pick

Fujifilm X-T30

Total Expert Score: 92/100 

A durable, versatile mirrorless digital camera to accompany your travels.

Best Large Sensor

Panasonic Lumix LX100 II

Total Expert Score: 82/100 

A class-leading premium compact filled with updated features.

Best Video

Sony CyberShot RX100 IV

Total Expert Score: 87/100 

Impressive 4k video and viewfinder packed into this compact camera.

Best Waterproof

Olympus Tough TG-5

Total Expert Score: 80/100

This little compact can tough it out on any outdoor adventure and in any weather conditions.

Best Budget

Canon PowerShot ELPH 360 HS
Canon PowerShot ELPH 360 HS

Total Expert Score: 80/100 

A practical budget compact with fast performance in auto mode.

Source: PetaPixel

Headshot of David Grossman

David Grossman is a staff writer for PopularMechanics.com. He’s previously written for The Verge, Rolling Stone, The New Republic and several other publications. He’s based out of Brooklyn.

link

Leave a Reply

Your email address will not be published. Required fields are marked *