High Contrast Grating Based Strain Sensor for Intraocular Applications

Glaucoma is a group of degenerative ocular diseases that affects millions of people worldwide. While the causes of glaucoma are still unidentified, there are recent studies that establish a link between glaucoma and the age-related loss in accommodation (presbyopia) resulting from the increasing inelasticity of the membrane attaching the ciliary muscle to the back of the eye. Consequently, to understand this relationship better, it becomes imperative that we be able to measure the strain at the choroid and correlate it with the intraocular pressure within the eye. Here, we report the development of an implantable, flexible, and biocompatible optical strain sensor based on a near-wavelength high contrast grating array. The change in the grating period corresponding to the choroidal strain results in a change in the observed color, allowing us to observe and measure small deformations. [2018-0034].