Pinhole glasses are devices made up of a frame fitted with a black plastic grid, on which holes are distributed. These openings positioned like a honeycomb allow only parallel light rays to pass, which reach the retina and avoid distortions associated with refraction defects. The result is a better view for increasing depth of field and central focusing.
With pinhole glasses, therefore, the objects are sharper (even if darker), since the more oblique rays are eliminated which are not able to reach fire correctly in an eye with refractive defects. Thanks to this operating principle, the eye is forced to look for light through pinhole holes, favoring continuous micro-movements that stimulate the periocular muscles. Pinhole glasses, therefore, could contribute to mitigate the myopia of accommodative spasm, but can hardly produce an effect on axial myopia.
