Realtime blur simulation of varifocal spectacle lenses in virtual reality

Virtual reality is a promising tool to study the influence of ophthalmic lenses on human perception. Independent of the actual refractive errors of the users’ eye, vision through different types of lenses can be simulated while allowing free eye and head movements and easy measurement of behavioural parameters. Especially for presbyopia, existing solutions often lead to visual discomfort. Multifocal spectacle lenses have a spatially varying optical power distribution leading to changing strength and orientation of blurred vision. Understanding the contribution of blur to visual discomfort and studying behavioral changes under the influence of lens blur is a promising application of a spectacle lens simulator. Here we present our framework to simulate spherical and astigmatic blur of corrective spectacle lenses. Size and orientation of a location dependent blur ellipse is calculated live in virtual reality using the depth information of the scene and precalculated power distribution of the lens.