Dyop® - Dynamic Optotype™

Helping the world see clearly, one person at a time




Personal Vision

Infant Vision

Color Screening

Professional Use


How it works

Using the Test

Visual Impairment

How it works

Using the Test



The Mechanics of Vision


We think in metaphors. 


The steam engine is used as a metaphor to describe our heart pumping blood through the body.  The computer is used as a metaphor to describe how we think. 


The functions of an electronic display or TV or camera can be used as a metaphor to describe how we see. 


When you look at a TV, or the display in front of you, you are actually seeing pixels rather than lines or shapes.  The small dots of light merge to give you the impression of seeing lines and shapes.  The pixels are so small, and the pixel density so great that, unless you get VERY close to that display, you see only the lines and shapes rather than those pixels.  In fact, being aware of the pixels gets in the way of comprehending them as lines and shapes or words.


Our eyes see the world as pixels rather than as lines and shapes.  What we see is recorded in the brain, but how we see starts as the stimulus of photoreceptors in the eye.  Those photoreceptors function as biochemical switches in response to light with the precise visual clarity (acuity) of what we see controlled by photoreceptors in the back of the eye.  Those photoreceptors tend to be responsive to specific colors of light - typically what we define as red, green, and blue.



Light passes through the lens to reach the retina


Retina Structure

Epithelium  =>  4 Neural Ganglia Layers  =>  Photoreceptors


   Retina Color Perception

Wavelengths of light






















Those color receptive photoreceptors in the back of your eye function as pixels in your visual camera.  Clusters of about 100 photoreceptors have their pixel-like signal converted by the neurons in the retina into the impulse of one optic nerve fiber.  That optic nerve stimulus is then transmitted to the brain where the brain uses that optic nerve stimulus to give us the perception/illusion of lines and shapes.


Light transmitted by the biological lens is also separated into wavelengths of color.  That effect typically has red focused slightly BEHIND the retina, green focused ON the retina, and blue focused in FRONT of the retina.  The disparity of the red/green/blue focal intensity is compared by the retina, and used by the brain, to autonomically transmit to the muscles controlling the shape of the biological lens, to regulate the instantaneous adjustment of the focal length of the lens (accommodation).


A Dyop® (short for dynamic optotype) is a calibrated visual target whose rotating/moving gap/segments create a strobic photoreceptor stimulus to measure visual acuity and refractions.  That strobic stimulus lets you sense the pixel response to the images you are seeing.


When the Dyop® gap/segment stimulus size is too small, or the distance is too far away, you cannot detect the visual pixel response or the motion of the Dyop® gap/segments.  That minimum Dyop® diameter and gap/segment stimulus where you CAN detect the Dyop® motion is the acuity endpoint. 


Current visual “standards” for acuity (how clearly we see) use an 1862 static-letter-based test to detect our perception of the differences between static letters such as “E” and “C” as the basis for acuity.

























1862 Snellen Vision Testing

21st Century Dyop® Vision Testing


However, the use of static letters is as much a test of cognition as it is acuity.  Those letters are culture and literacy biased, are significantly imprecise and inconsistent, and don’t sufficiently meet the higher precision needs of 21st century technology in measuring visual acuity.  Static letter tests, rather than enhancing visual acuity, increase visual stress, increase decision fatigue, and create a less precise visual acuity measurement. 


The Dyop® motion detection process increases accommodative rest, takes the guesswork and visual stress out of vision testing, and potentially increases the efficiency of the visual testing process.  Dyop® vision tests are more accurate than static image tests, more precise, more consistent, potentially faster to use, and do not require the ability to read, let alone the ability to read English. 


Calibrated Dyop® tests are intended as a global replacement for Snellen, Sloan, and Landolt optotypes


People who are able to consistently see more clearly are more productive and able to successfully participate and benefit from 21st century technology significant increases.


 “Any sufficiently advanced technology is indistinguishable from magic.”
- Arthur C. Clarke’s Third Law




As a culture we are only as good as our memory.  As a species we are only as good as our vision.


Just as the hand, held before the eye, can hide the tallest mountain, so the routine of everyday life can keep us from seeing the vast radiance and the secret wonders that fill the earth.

-          Chasidic, 18th Century




The Dyop® (Dynamic Optotype™) tests and concept are covered under U.S. Patent US 8,083,353

and International Published Patent WO 2011/022428.

For further information contact: Allan Hytowitz at Allan@Dyop.org

5035 Morton Ferry Circle, Alpharetta, GA, 30022   /   678-893-0580

Copyright©2016 Dyop® Vision Associates.  All Rights Reserved.




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