Using a mockup of the company’s VisionOptimizer system, DigitalVision CTO Jose Garcia points to the location of a 24-inch telescope grade spherical mirror that a patient will view from the exam chair. Computer-controlled corrective lenses will be housed in a tray above the patient’s head and will be remotely imaged in front of the patient, allowing corrections to be optimized under natural viewing conditions. Also shown are CEO Keith Thompson and GTRI’s David Roberts and Leanne West. Image: Gary Meek |
With research and development assistance from the Georgia Tech Research Institute (GTRI) and seed funding from the Georgia Research Alliance
(GRA), an Atlanta-based company is developing what it hopes will be the
next-generation instrument for optimizing eyesight for the hundreds of
millions of people who wear glasses or contacts—or who are candidates
for corrective surgery.
To
be used by optometrists and ophthalmologists, the instrument—known as
the VisionOptimizer—is intended to provide more accurate vision
measurements, along with a more patient-friendly and engaging vision
test. The company believes its system will facilitate the
custom-manufacturing of spectacles and contact lenses that provide
better eyesight and improved wearing comfort compared to conventional
prescriptions.
“We’ve
known for a long time that many prescriptions produced by existing
methods really didn’t optimize the patient’s vision, but until now we
haven’t had a way to make more accurate measurements or to use that
information to produce better lenses,” says Keith Thompson, a surgeon
and ophthalmologist who is also the CEO of DigitalVision LLC, the
company developing the VisionOptimizer. “Today’s patients need
razor-sharp vision to use their smart phones, spend hours at their
computers and enjoy sports on the weekends.”
Eye
doctors currently prescribe glasses and contact lenses using
measurements obtained with the phoropter, an instrument that has changed
little since it was introduced in the early 1900s. During a
conventional vision test, the patient looks through the phoropter at an
eye chart while the doctor dials different corrective lenses into
position. The patient is asked to choose which set of lenses provides
the clearest view of letters on the eye chart.
Phoropter
measurements are limited to increments of a quarter of a diopter of
resolution. The resulting glasses or contact lenses often fail to
provide all of the vision improvement now possible with modern
computer-controlled lens fabrication technology, Thompson notes. And
errors cause as many as one in seven prescriptions to be re-made.
During
the 1970s, a system called the Humphrey Vision Analyzer was introduced
to measure vision more accurately than the phoropter, and to provide a
better patient experience. Instead of viewing an eye chart through a
bulky lens dial, the system projected images onto a mirror, and the
patients adjusted a set of knobs to improve image quality. The Humphrey
system, which is no longer in production, used a unique sliding lens
system to evaluate smaller incremental changes than the phoropter could
measure. But while the device made more accurate measurements, the
fabrication equipment needed to manufacture corrective lenses to match
that accuracy has only become available within the last ten years,
Thompson adds.
With
help from GTRI, DigitalVision is producing a new system that adds
patented measurement technology and other improvements to the Humphrey
concept. Using computer algorithms not available in the 1970s, the GTRI
researchers have redesigned the instrument’s optical system for higher
performance. The original assembly of pulleys and wires used to move the
lenses will be replaced by microcontrollers and inexpensive actuators.
“We
believe we have solved all of the fundamental issues that needed to be
addressed,” says David Roberts, a GTRI senior research scientist who is
leading the research and development project. “The challenges are now
down to engineering—controlling all the tolerances and keeping
everything in alignment.”
The
result, according to DigitalVision, will be a system in which a patient
sits in an exam chair and looks at images in a two-foot diameter
telescope-grade mirror while providing feedback through a hand
controller.
The
system will measure the amount of nearsightedness, farsightedness, and
astigmatism present and determine higher-order aberrations that the
phoropter cannot detect. The doctor will be able to show patients how
much better they could see with the new prescription compared to their
old one by using real images, such as street signs and golf greens. The
VisionOptimizer’s specifications will be transmitted electronically to a
fabrication laboratory that will custom manufacture spectacle and
contact lenses.
Rendering shows how patients would interact with the VisionOptimizer under development by an Atlanta-based company, DigitalVision. In an exam room, patients would view images on the mirror in front of them and provide feedback via a hand controller. Image: DigitalVision |
“It’s
more real world than what eye doctors are using today, and has
commonalities with video games for a population that is accustomed to
interacting with computers,” says Leanne West, a GTRI senior research
scientist who is also working on the project. “For today’s population,
the new vision test will be a fun and engaging experience.”
A
patent-pending head and eye tracking system developed by GTRI is
expected to improve the accuracy of the test by eliminating alignment
errors. GTRI’s tracking system will also eliminate the need for
restraining the patient’s head, and should allow easier examinations of
children, the elderly, and people with disabilities.
“As
you move your head around, the images will go with you,” explains Jose
Garcia, the company’s chief technology officer. “One of the issues with
testing young patients, as well as older patients and people with
disabilities, is that patient movement during the vision test leads to
errors. With GTRI’s eye and head tracking system, we expect that these
groups can be tested with confidence that they are seeing the image
properly and responding to the test.”
The
Georgia Research Alliance, a public-private organization that supports
the development of technology companies in Georgia, has provided the
company with seed funding for commercialization.
“Anyone
who has had an eye examination will appreciate the potential of
DigitalVision’s technology,” says Lee Herron, vice president of
commercialization for the GRA. “While the product is still in the early
stages, the company is making steady progress toward bringing its system
to market.”
DigitalVision
expects to have a prototype system ready for beta testing in as little
as six months, and hopes to receive expedited approval from the U.S.
Food and Drug Administration (FDA). If all goes as planned, doctors may
be able to purchase the new system in about a year.
“We
feel that this market is ready for a disruptive technology,” Garcia
adds. “Doctors in this space are hungry for technology to replace the
phoropter. This system will allow doctors to introduce a new category
of corrective products to their patients.”
