Advanced Visual Testing and Refraction with Adaptive Optics Technology

Enrique Josua Fernández, Pedro M. Prieto, Bart Jaeken, Lucia Hervella, Guillermo M. Pérez, Pablo Artal

Abastract: The incorporation of adaptive optics (AO) technology in modern ophthalmic instruments is permitting to obtain and use advanced refractions, beyond defocus and astigmatism. With this technology, patients can test in advance customized or premium optical solutions, offering the possibility to choose the most suitable alternative for the correction of their vision. Among others, those can include multifocal profiles, diffractive optics, advanced or aspheric monovision. In this context, a new AO system is presented in this paper with enhanced capabilities for visual testing and refraction. The experimental set-up incorporated a fluidic lens for the control of defocus, in combination with a liquid crystal on silicon (LCoS) phase modulator for the manipulation of the rest of aberrations. A motorized diaphragm acting as the exit pupil assured full control of optical conditions during the evaluation of vision. An OLED display in the stimuli relay enabled to perform different visual tests in white light simultaneously to the manipulation of ocular aberrations. Those were objectively retrieved by a Hartmann-Shack wavefront sensor in IR light during the operation of the system. Chromatic aberration was compensated in the system well below perceivable levels for the eye. The set-up was successfully demonstrated in real patients. Some examples of vision through customized profiles in normal eyes were provided. The incorporation of a fluidic lens in the system significantly augmented the performance of the phase modulator, since the latter was discharged from defocus. That is typically the most relevant aberration in terms of amplitude in the human eye. With those new features, the instrument significantly expanded the range of population that can benefit from AO technology, eventually being able to operate in the pathologic eye.