Holografik ekran kullanan intraoküler lens temelli görüntü simülatörü

Cataract is defined as the cloudiness of the crystalline lens structure due to aging, trauma, etc. It is one of the most common preventable eye diseases in the world. The only treatment is surgery. During the surgery, the cataractous lens is removed and an artificial intraocular lens is implanted into the eye. There is an ongoing research effort to improve intraocular lens optical characteristics and depth-of-field to make patients totally spectacle-free after cataract surgery. However, modeling the vision through a cataractous lens and demonstrating various intraocular lens options before surgery are both significant challenges. In the first part of this thesis research, we developed an eye model to assess the performance of different intraocular lens options. Furthermore, we used the results of the eye model in a custom holographic vision simulator developed in our group to predict the postoperative vision of patients before surgery. In the clinical assessments, we employed a computational holographic display as it is the only technology that can generate digitally programmable exit pupils and simultaneously display content at different depths. Our artificial eye model was used to evaluate the optical performance and the point spread functions of different intraocular lenses. Those PSFs were then used to compute phase holograms to display on our custom holographic vision simulator. We characterized three different intraocular lenses using a standardized resolution target and point light source illumination using an light emitting diode. Monofocal, bifocal, and trifocal intraocular lenses exhibited a contrast decrease of 5%, 42%, and 45% and a resolution limit of 4.49, 4.00, and 4.00 lp/mm at 35cm (using 8% modulation transfer function criteria), respectively. Monofocal intraocular lenses had the best resolution and contrast. The multifocal lenses produced prominent photic phenomena such as halos and glare around bright light sources, reducing contrast and resolution. We compared our results with the literature and confirmed that the visual functions of intraocular lenses could be successfully modeled and simulated using a holographic display before surgery. In the second part of this research, we used our eye model and developed a cataractous lens simulator for progressive levels of opacification, which is achieved by applying a reversible chemical procedure on the intraocular lens surfaces. After the lens is fully or partially immersed in acetone, subsequent testing of the lens in distilled water results in a progressive change in opacification level within minutes. We objectively measured the quality of vision by obtaining modulation transfer function curves, transmission, and spectroscopic measurements at different opacification levels. By simulating variable opacification across the IOLs, we tested how vision changes from less dense to more dense cataractous regions in a holographic display system with programmable small exit pupils. All results were consistent with the expected vision degradation caused by natural opacification.