Seeing our insides with a bug’s eye view

It’s about time we consider an insect’s perspective. By taking the wide-angle view of an insect eye and tweaking it with the focusing ability of a human eye, researchers have created a lens the size of a pea that can nab both wide images and zero in on details. The tool can be used in laparoscopes, the tiny cameras that help surgeons explore inside the body. It might even find its way into smartphone cameras if researchers manage to make it a bit smaller. With this new insect-inspired lens, scientists are improving our ability to capture the world around us—and possibly inside us too.

Although seeing like an insect means only being able to see things up close, it also means seeing wide—much wider than we can currently imagine. Insects achieve this thanks to their compound eyes, which are made of hundreds of small lenses that wrap around their heads like helmets. “If you think of a dragonfly zooming around in the air, it needs to be able to look for food, but also escape from other predators looking for it as well,” said Diana Cox-Foster, an entomologist at Pennsylvania State University, who was not involved with the lens project. “That means the bigger the view, the better.”

Insects, however, have a “pixilated” view of the world, which causes them to see things the way they might appear to us in a low-resolution photo. The human eye works very differently:  the lenses in our eyes constantly change shape using specialized cilliary muscles to keep both near and far away images in focus.

To give the human eye a new kind of seeing power, biomedical engineer Yi Zhao of Ohio State University in Columbus and colleague Kang Wei molded a simpler version of the insect’s compound eye using a flexible polymer. “We wanted to see if it was possible to have one lens that had many smaller lenses embedded into it,” said Zhao. To test how well the lens focused, the pair mounted the letters “O-H-I-O” on tiny stands made of the same polymer and pumped fluid into the lens to change its shape. In this manner they were able to focus on each letter.

As the researchers zoomed in on one letter, the other letters became blurry but remained in view, mimicking the way the human eye works, according to the team’s report in the Technical Digest of the 25^th IEEE International Conference on Micro Electro Mechanical Systems.

“This is definitely an interesting and novel optical device,” said Chris Sarantos, a biomedical engineer at City University of New York. He said that although the tool could have many useful applications, using it to explore inside the human body is “iffy.” He wonders if surgeons would want different parts of the image to be fuzzy as they move the laparoscope in the body. “Maybe applying imaging software could recompose the images into one and solve this issue,” he suggested.

Currently, a surgeon using a laparoscope has to do a lot of rotating and re-adjusting of the lens to get just the right angle. “This means more surgical time, more costs associated with using the operating room and more risk to the patient,” said Zhao. By widening the view, he and his colleague hope to help surgeons narrow in on problems in the body while reducing risks and costs.