Brett Smith for redOrbit.com – Your Universe Online
Astronomers have developed groundbreaking optical techniques to bring distant stars into focus and this same technology is now being appropriated by eye care professionals to improve their analysis and corrective methods.
According to a recently published review in the journal Optometry and Vision Science by Indiana University optometrist Larry N. Thibos, the concept of ‘wavefront optics’ is transforming how vision professionals are looking at issues they encounter in their everyday practice.
“Instead of light arriving at a lens from a star, imagine a point source of light reflected from the retina and emerging from the eye’s optical system as a wavefront,” Thibos explained in the review. “If we can measure the slope of the emerging wavefront at many points on the wavefront, then we have all of the information needed to reconstruct the shape of that wavefront, thereby obtaining a comprehensive description of the eye’s optical aberrations.”
Thibos said the traditional method for assessing the eye involves complications that are eliminated by wavefront optics.
“Although it is possible to accomplish the same result by measuring the intersection point of light rays with an image plane near the focus point, that approach is more difficult because the rays overlap and get confused near the focus point, so they must be isolated and measured sequentially,” he said “By measuring wavefront slope near the eye, where individual rays are well separated, it becomes possible to make many measurements simultaneously.”
According to Dr. Anthony Adams, Editor-in-Chief of Optometry and Vision Science, an array of ‘higher-order’ abnormalities in the eye can cause problems for both the patient and the eye care professional looking to diagnose any problems.
“In the past two decades, optometry and ophthalmology researchers have borrowed techniques for measuring and correcting these higher-order abnormalities,” Adams said. “Astronomers already used these techniques to enable a clear telescopic view of planets and stars, undistorted by the focusing aberrations resulting from the earth’s atmosphere.”
In his review, Thibos predicted important advances in vision care that would result from pursuing wavefront optics approaches, such as monitoring potential deterioration of the tear film, assessing the outcomes of certain corrective therapies, and tracking visual abnormalities in growing eyes. He added that some cutting-edge methods are already being used.
“Some of these corrections are even finding their way into contact lens and spectacle designs,” he said.
In addition to describing the rewards of pursuing a wavefront optics approach, Thibos’ review includes several diagrams and teaching tools that could be used in an educational setting.
As noted in the journal article, Thibos was recently named the 2012 winner of the American Academy of Optometry’s Charles F. Prentice Medal, which is awarded annually to someone who has contributed significantly to the visual sciences.
“Dr. Thibos is quite unique in his extraordinary ability to relate these advances in optics to the very fundamentals of ophthalmic optics which the ‘Father of Optometry,’ Charles F. Prentice, articulated more than 120 years ago,” Dr. Adams comments. “It is fitting that he was awarded the Charles F. Prentice Medal for his work—the highest Award of the American Academy of Optometry.”