Why the blink count is not enough

When you look at the small EyesRhythm window, you see a number, and it isn’t how many times you blinked today or a streak you could collect. It’s a picture of this stretch of work, showing how often you blinked and whether those blinks were spread out or bunched up.

Most blink apps only count, which sounds useful until you remember that your eyes don’t live on a total. They live on the gaps between blinks, which is when the surface starts to dry. A blink rate detector has to look at both.

We already wrote about why screens make you blink less. This one is about the number next to your work, and how to read it without turning it into another job.

The same six blinks, two different minutes

Picture a minute with six blinks in it, which is already a low rate, the kind researchers saw when office workers looked at a screen instead of sitting quietly. ¹ Those same six blinks can still mean two different minutes.

If they are spread out, you wait about twelve seconds between each one, and the eye gets a little dry before a blink wets it again. If they come in two clumps, with a long empty stretch in the middle, more than half the minute can go by with no blink at all. The count is the same, but the drying is much worse, and a 2023 paper drew that picture with the same average and very different uncovered time. ²

Same six blinks. Different minute.

Even

A blink about every 12 seconds

Lumpy

A cluster, a long wait, another cluster

After Cardona, Argilés and Pérez-Cabré, 2023. The average looks the same, and the long gap is where the eye dries.

“A complete characterization of blink parameters is relevant to better understand ocular dryness related to surface exposure and to advice patients towards a reeducation of their blinking habits.”
Cardona, Argilés and Pérez-Cabré, 2023²

What they mean is that the count is only part of the story, and that people can relearn a better blink habit. How often you blink is the rate, and how steady those blinks are is the regularity. You need both, because slow and even still leaves the eye dry, and fast but bunched still leaves a long dry wait.

Two questions, one score

EyesRhythm puts those two things into one number, the Ocular Rhythm Index, or ORI, which runs from 0 to 100 and sits in the window.

How often still matters more, because a blink that never comes cannot be even. How steady still matters too, so a lumpy minute doesn’t look fine just because the count added up.

The app is built for desk work, not for talking and not for sleep, since people blink more when they talk and less when they stare at a screen. ¹ EyesRhythm aims at a comfortable screen pace, about 15 to 20 full blinks a minute, spaced out enough that the eye stays wet.

~18

blinks / min

A calm minute at the desk

0–100

ORI

How often and how even

default nudge

When the score has been low

About 15 to 20 blinks a minute is a healthy pace at a screen, and ORI is that rate plus how even the gaps were.

Regularity is simply whether the waits between blinks are similar or all over the place. ² Even waits score high, while a clump followed by a long wait scores low. EyesRhythm looks at your recent blinks this way, not as a medical test, but as a live picture of this stretch of looking.

Even concentric ripples on still water, spreading from a single point of light. — Regularity is how even the gaps are, so the count can look fine while the waits are all over the place.

How to read the window

You don’t have to watch the number, because the app is meant to sit beside your work. When you do look, this is enough:

High ORI. You have enough blinks, and they are not arriving in panics and silences, so this minute is going okay.
Around the middle. This is where the default nudge lives, when you are blinking less or the gaps have gone lumpy, or both. A full blink, a look away, and then back to the page is often all you need.
Low ORI. The waits have gotten long, or there are too few blinks, and when the letters go soft this is usually why, not the screen.

The score only runs while the camera can see both eyes looking at the screen, so if you look down, turn to a side monitor, or leave the chair, it pauses on purpose. That isn’t a bug, because it’s only counting screen time, and the camera setup guide is the short version of sitting so those minutes count.

Comfortable blinking isn’t a perfect beat, and the waits can vary a little. Sore, dry eyes often blink more, with shorter gaps, as if the eye is asking for another wipe. ³ A good score isn’t a locked 100 so much as enough blinks without being chaotic, and the number will move, which is normal.

“The tendency towards decreased blink rate during visual function tasks, such as computer use, reading, video gaming, and watching TV can exacerbate the signs and symptoms of dry eye.”
Johnston, Rodriguez, Lane, Ousler and Abelson, 2013³

Staring at a screen, a page, a game, or the TV often means fewer blinks, and dry, tired eyes get worse when that goes on.

A two-minute practice

Nobody decides to blink less, and focus does it for you. The way back isn’t a lecture so much as a few minutes of even blinking, so your eyelids remember when work gets intense. ²

Practice is a two-minute coach where a ball moves and a quiet beep comes about every three seconds, which is close to twenty blinks a minute. Follow the ball with your eyes, blink on the beep, and keep your head still. Let the lids actually meet, because a half blink doesn’t wet the eye.

Then close it and go back to work. You don’t need to watch yourself, because a little practice is enough for the live score to have something to climb toward.

A round dewdrop on a sage leaf, catching blue sky like a tiny lens. — Blinking keeps the eye wet, and even blinking is what a long screen day often forgets.

What this number is not

ORI isn’t a diagnosis or a grade. Bad light, glasses, a camera that cannot see your eyes, or a meeting already using the webcam can all move the number, because the app is a desk tool, not a clinic.

A low stretch doesn’t mean something is wrong with you. If your eyes stay sore, or your vision changes, see an eye doctor rather than asking a window on your laptop.

Leave the window where you can see it if you want the nudge, or tuck it away and let the quiet pulse do the work. Either way, what matters is this minute, not a count on a sticky note.

Sources

Tsubota K, Nakamori K. Dry eyes and video display terminals. New England Journal of Medicine. 1993;328:584. doi:10.1056/NEJM199302253280817
Cardona G, Argilés M, Pérez-Cabré E. Loss of blink regularity and its impact on ocular surface exposure. Diagnostics. 2023;13:2362. doi:10.3390/diagnostics13142362
Johnston PR, Rodriguez J, Lane KJ, Ousler G, Abelson MB. The interblink interval in normal and dry eye subjects. Clinical Ophthalmology. 2013;7:253–259. doi:10.2147/OPTH.S39104

EyesRhythm is a wellness companion, not a medical device. It is not intended to diagnose, treat, or prevent disease. Persistent discomfort or a change in vision belongs with a licensed eye-care professional.