The lens bends light rays that enter the eye, helping patients to see, the academy said. The natural lenses are clear but those suffering from cataracts have cloudy lenses.

Powell prism (Powell Lens) is a specially designed aspheric optical prism, mainly used to convert Gaussian beams (such as laser beams) into linear light spots evenly distributed along a straight line.

“The lens of the eye, when we’re born, is this: it bends light rays and it’s nice and clear,” said Dr. Madhu Gorla, an ophthalmologist at Chicago Glaucoma Consultants.