Abstract
Purpose: :
Adaptive lenses with various tunable power and effective aperture have wide applications in vision care, including vision correction, vision assessment, and depth-resolved ocular imaging. For vision correction, the existing spectacle lenses for correction of presbyopia have a limited field of view for each vision task, requiring user to gaze down to accomplish near vision and in some cases causing dizziness and discomfort. Progressive lenses cause some distortion. An electro-optic lens allows voltage controlled change of the focusing power across the entire aperture and provide a new approach to correction of presbyopia by eliminating the above limitations. The current commercially available phoropters are bulky and expensive. Adaptive lenses may provide a much more compact and low-cost solution. Furthermore, the conventional 3D imaging of the eye is achieved by mechanics scanning of focus in depth. It would be more attractive if a new adaptive compound objective lens can be used for nontranslational depth-resolved 3D imaging.
Methods: :
For the first time to our knowledge, we have designed and fabricated tunable liquid crystal lenses with large aperture and large tunable range needed for correction of presbyopia by incorporating nanotechnology and cost-effective microfabrication technology. By using electromagnetic actuator, we are able to implement tunable liquid lenses with large aperture and very large tunable power. The power of the lens is tuned by controlling the shape of the membrane of the lens with an applied DC voltage. Furthermore, these varifocal lenses are used for a compound adaptive objective lens for high-resolution high-speed 3D imaging, including confocal imaging and OCT imaging.
Results: :
We have designed and fabricated a tunable liquid crystal lens with large aperture (over 20 mm), large tunable range (over 3 diopters) and low driving voltage by incorporating nanotechnology and cost-effective microfabrication technology. We have also achieved tunable liquid lenses actuated by electromagnetic force with 20 mm - aperture and a power tunable range from -25 diopters to +25 diopters. These lenses have been used to build the prototypes of adaptive spectacles, visual simulator, and new phoropter. Vision test results will be shown. The nontranslational confocal imaging system has a field of view of 1mmx1mm, transverse resolution of 2μm, and a depth scanning range of 1mm.
Conclusions: :
The electro-optic tunable lenses with large aperture and large tunable range are promising for vision correction, vision assessment, and 3D eye imaging with no moving parts.
Keywords: aging: visual performance • imaging methods (CT, FA, ICG, MRI, OCT, RTA, SLO, ultrasound) • presbyopia