Does astigmatism get worse over time?

It can change gradually, particularly in younger people whose eyes are still developing, which is why an annual check is generally recommended even if nothing feels different.

Can contact lenses correct astigmatism?

Yes, toric contact lenses are designed specifically for astigmatism, but they need a precise axis measurement to sit correctly on the eye, similar to how glasses need the axis to be exact.

Why do cheap sunglasses seem to make glare worse at night?

An inaccurate prescision or a lens without decent anti-reflective coating scatters more incoming light rather than focusing it cleanly, which can make halos and glare more noticeable, not less.

Is uncorrected astigmatism dangerous for night driving?

It can slow how quickly you register glare and read road signs clearly, which matters for reaction time. If you notice halos while driving at night, it's worth getting checked before it becomes a bigger issue on the road.

How often should I get rechecked?

Annually is the general guideline, or sooner if halos or blur noticeably worsen in between visits.

Can glasses cure astigmatism permanently?

No. Glasses and contact lenses correct the distortion only while you're wearing them, they don't change the shape of the cornea. Refractive surgery can reshape the cornea permanently, but not everyone is a suitable candidate, and that decision sits with an eye surgeon, not an optical shop.

Does anti-reflective coating fix night halos on its own?

It helps with the portion of glare caused by internal lens reflections, but it doesn't correct astigmatism itself. If the cylinder power or axis is off, coating alone won't resolve the halos, the prescription needs to be right first.

Can toric contacts correct astigmatism the same way glasses do?

Yes, toric lenses are built with the same cylinder-and-axis logic as glasses, matched precisely to your eye's curvature and typically stabilized with weighting so the lens doesn't rotate out of position.

Home › Learn › Astigmatism and Night Glare: Why Lights Look Worse After Dark

EYE HEALTH

Astigmatism and Night Glare: Why Lights Look Worse After Dark

Written by Alvin · Manh Long Optical, 147A Le Duan, Cua Nam, Hanoi · Updated 11 September 2026

In short: Uncorrected astigmatism scatters light unevenly across the retina, which is why headlights and streetlights produce more visible halos or starbursts at night than in daytime. Getting the astigmatism power and axis right, combined with a good anti-reflective coating, usually fixes it. Full digital refraction is done at Manh Long Optical, 147A Le Duan, Cua Nam.

What astigmatism actually is

Astigmatism means the cornea, or sometimes the lens inside the eye, curves more steeply in one direction than another, closer to the shape of a rugby ball than a football. Light entering the eye doesn't focus to a single sharp point on the retina, it focuses to two separate points, or a spread-out line, depending on the direction it's traveling. The result is mild to moderate blur at every distance, not just up close or far away, and it's extremely common, most people have some degree of it.

Why night vision is worse

In low light, the pupil dilates to let more light in. A larger pupil opening exposes more of the eye's irregular curvature to incoming light, which is exactly the part astigmatism distorts. During the day, a smaller pupil naturally masks some of that distortion. At night, it doesn't, and the effect is most visible around point sources of light, headlights, streetlights, traffic signals, where the scattered focus shows up as a halo, a starburst, or streaking rather than a clean point.

Signs to watch for

Halos around lights, especially when driving after dark, are the most commonly reported symptom. Alongside that: mild blur that doesn't fully clear with squinting, eye strain or headaches after reading or screen use, and needing to tilt your head slightly to bring things into focus. If halos are new, getting rapidly worse, or only affecting one eye, that's worth a proper check rather than assuming it's routine astigmatism, since those patterns can also point to early cataracts or a corneal change.

How lenses fix it

A correct prescription for astigmatism has two extra numbers beyond a standard spherical prescription: a cylinder power (CYL) and an axis, the precise angle, in degrees, that the correction needs to sit at. Get the power right but the axis even slightly off, and the correction doesn't fully resolve the light scatter, symptoms including night halos can persist even though the prescription looks correct on paper. This is also why loose or slipping frames matter more for astigmatism than for a simple prescription, the lens rotating even a few degrees off its fitted position can undo an otherwise accurate correction.

Common questions

Does astigmatism get worse over time?: It can change gradually, particularly in younger people whose eyes are still developing, which is why an annual check is generally recommended even if nothing feels different.
Can contact lenses correct astigmatism?: Yes, toric contact lenses are designed specifically for astigmatism, but they need a precise axis measurement to sit correctly on the eye, similar to how glasses need the axis to be exact.
Why do cheap sunglasses seem to make glare worse at night?: An inaccurate prescision or a lens without decent anti-reflective coating scatters more incoming light rather than focusing it cleanly, which can make halos and glare more noticeable, not less.
Is uncorrected astigmatism dangerous for night driving?: It can slow how quickly you register glare and read road signs clearly, which matters for reaction time. If you notice halos while driving at night, it's worth getting checked before it becomes a bigger issue on the road.
How often should I get rechecked?: Annually is the general guideline, or sooner if halos or blur noticeably worsen in between visits.
Can glasses cure astigmatism permanently?: No. Glasses and contact lenses correct the distortion only while you're wearing them, they don't change the shape of the cornea. Refractive surgery can reshape the cornea permanently, but not everyone is a suitable candidate, and that decision sits with an eye surgeon, not an optical shop.
Does anti-reflective coating fix night halos on its own?: It helps with the portion of glare caused by internal lens reflections, but it doesn't correct astigmatism itself. If the cylinder power or axis is off, coating alone won't resolve the halos, the prescription needs to be right first.
Can toric contacts correct astigmatism the same way glasses do?: Yes, toric lenses are built with the same cylinder-and-axis logic as glasses, matched precisely to your eye's curvature and typically stabilized with weighting so the lens doesn't rotate out of position.

A note on health: Information in this article is for reference only and doesn't replace an eye doctor's assessment. If you have ongoing eye pain, blurred vision or headaches, please visit Manh Long Optical or a medical facility for an accurate check.

Come compare in person

Reading about it only gets you so far. Trying it on tells you more. Come to 147A Le Duan for a refraction test and frame trial, testing, cutting and fine-tuning done in one visit.

Manh Long Optical — 147A Le Duan, Cua Nam, Hanoi
Open daily 8:00 – 21:30
0777 986 999 · WhatsApp · Zalo · mlong.optical@gmail.com · Directions