The human crystalline lens has the capability to dynamically change its shape to focus near and far objects. By age 55, the accommodation capability is lost and optical aids are needed for near vision. Many questions remain open that are critical to understand accommodation, the failure in presbyopia, and the prospects for its correction. Multifocal presbyopic corrections are increasingly used. However, the ideal multifocal pattern, and the optical factors affecting depth-of-focus and adaptation to simultaneous vision remain to be elucidated. The most satisfactory treatment of presbyopia should rely on the restoration of the dynamic and continuous focusing ability of the eye, and this could be achieved in the form of accommodative intraocular lenses (IOLs). Current approaches, relying on potential IOL axial shifts, have proved little effective accommodative amplitude.The project will seek in nature innovative solutions to treat presbyopia. Deeper understanding of the crystalline lens changes with dynamic accommodation and aging will be gained. Novel imaging techniques will be developed and used to assess the dynamic changes of crystalline lens structure, gradient index distribution and microscopic structure of the lens fibers and capsule. In addition, the treatment of presbyopia by multifocal corrections will be explored. Wavefront sensing and optical coherence tomography will be used to understand the bases for the multifocality found in some animal species (as possible inspiration for multifocal patterns), and adaptive optics and visual simulation to understand the reasons for the limited performance of current multifocal treatments, to investigate neural adaptation to the blur in simultaneous vision and to test the proposed new multifocal patterns. Finally, the understanding of the crystalline lens properties and the biomechanics of the implanted IOLs gained in the project will allow to develop a first prototype of crystalline-lens mimicking accommodative IOL.