Shape-changing lens blends human and insect vision

One example of biomimicry that keeps popping up on the pages of Gizmag is the use of insect eyes as a model for innovative new optical devices. It seems that the potential for development in this area is far from exhausted with the announcement of another bug-inspired lens breakthrough from Ohio State University. This experimental lens developed by associate professor of biomedical engineering and ophthalmology, Yi Zhao, combines the wide angle properties of insect vision with the depth-of-field capabilities of a human eye.

The 5 mm-wide prototype lens is made up of a series of fluid-filled transparent polymer pockets arranged over a dome that can be contracted and expanded to change the focus and direction of the lens. At present, the fluid is pumped in and out by hand from an external reservoir, but a version made from an active polymer that changes shape in response to electric signals is also in the works.

“Our eye can change focus. An insect eye is made of many small optical components that can’t change focus but give a wide view. We can combine the two,” says Yi Zhao, associate professor of biomedical engineering and ophthalmology at Ohio State. “What we get is a wide-angle lens with depth of field.”

While we've seen super-wide angle lenses developed using a bug-eye structure before, the ability to change focus by altering its shape is what gives the lens added potential for applications such as laparoscopy, microscopes and smartphone cameras, where being able to achieve shallow depth-of-field without adding any moving parts has clear advantages.

“With our lens, doctors could get the wide-angle view they need, and still be able to judge the distance between the lens and tissue," says Zhao. "They could place instruments with more confidence, and remove a tumor more easily, for example.”

The researchers say that tests on the prototype lens to date have demonstrated the ability to shift focus and produce images of varying depth. Further work is being done to make the device smaller and to develop a self-contained shape-changing mechanism, with the aim of eventually licensing the technology to industry through Ohio State's Technology Commercialization and Knowledge Transfer Office.

Source: Ohio State University