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→Insights about Transient Astigmatism and Cylinders
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Well, it looks like cylinders ruin everything. My theory is that there are 2 mechanisms: the eye itself shrinks and grows based on defocus for emmetropization, which can adapt based on the incoming light, and then visual perception changes, but it can only adapt to gradual changes. That's why blur adaptation is bad, as the visual system stops adjusting, while the eye continues to adjust, so the axial length and visual perception go out of sync, later leading to lots of accommodation to compensate for distortions such that the light input matches the visual perception's requirements. | Well, it looks like cylinders ruin everything. My theory is that there are 2 mechanisms: the eye itself shrinks and grows based on defocus for emmetropization, which can adapt based on the incoming light, and then visual perception changes, but it can only adapt to gradual changes. That's why blur adaptation is bad, as the visual system stops adjusting, while the eye continues to adjust, so the axial length and visual perception go out of sync, later leading to lots of accommodation to compensate for distortions such that the light input matches the visual perception's requirements. | ||
If you stop using glasses, your eye's axial length adjusts, but the visual system doesn't care. It'll still think your vision is distorted in the same way as before | If you stop using glasses, your eye's axial length adjusts, but the visual system doesn't care. It'll still think your vision is distorted in the same way as before and has a dependency on the lenses you used, while accommodating as needed to make it focused. | ||
Whenever a cylinder is changed, the eye compensates for it, affecting all later focal planes. Equalizing seems to change the offset for one eye when "navigating" the focal planes. Simple binocular spherical changes affect the offset for both eyes when navigating the focal planes. When undoing the changes, after you hit the cylinder change point, it applies the cylinder to the entire focal plane, and then you have to fix it using the nearer focal plane before continuing to reduce. At the change point, everything before the change point was still distorted differently. The visual system just stops applying cylinder correction to the entire focal plane, making it seem like the cylinder was applied to the near planes and the opposite cylinder was applied to the far planes. | Whenever a cylinder is changed, the eye compensates for it, affecting all later focal planes. Equalizing seems to change the offset for one eye when "navigating" the focal planes. Simple binocular spherical changes affect the offset for both eyes when navigating the focal planes. When undoing the changes, after you hit the cylinder change point, it applies the cylinder to the entire focal plane, and then you have to fix it using the nearer focal plane before continuing to reduce. At the change point, everything before the change point was still distorted differently. The visual system just stops applying cylinder correction to the entire focal plane, making it seem like the cylinder was applied to the near planes and the opposite cylinder was applied to the far planes. | ||
It's interesting how our visual system can compensate for cylinder and spherical distortion. | It's interesting how our visual system can compensate for cylinder and spherical distortion. | ||