Astigmatism Blur Illustration

Astigmatism can cause light to focus differently across eye meridians. The preview uses layered copies of the same scene to make direction and relative strength easier to understand. It does not calculate the optics of an eye. The clear reference stays unchanged so you can compare edges, letters, and point lights.

The percentage changes only the amount of screen-space layer offset, while the angle rotates that graphic effect. Neither control represents CYL, AXIS, diopters, or any other field on a prescription. Real blur depends on the complete prescription, pupil size, accommodation, tear film, lighting, and whether correction is being worn.

A glasses prescription describes optical correction, not a complete digital blur recipe. Two people with the same cylinder and axis may describe vision differently, and a display cannot reproduce glare, contrast loss, retinal factors, or brain adaptation. Do not use this page to estimate prescription strength or decide whether to change eyewear.

Schedule a comprehensive exam if blur, squinting, headaches, eyestrain, halos, or night-driving difficulty persist. Sudden vision loss, severe eye pain, new flashes, or a curtain-like shadow need urgent professional assessment.