Introducing the Dyop®

The “Revolutionary” Method for Measuring Visual Clarity (Acuity)

Helping the world see more clearly, one person at a time.

Counter-Clockwise

 

 

 

 

 

 

 

 

 

A black and white poker chipDescription automatically generated

A black and white poker chipDescription automatically generated

A black and white poker chipDescription automatically generated

A black and white poker chipDescription automatically generated

A black and white poker chipDescription automatically generated

 

 

 

 

 

 

 

 

 

 

Click here for the introductory Dyop Videos

 

Print Version of this page

 

Clockwise

The world we see is dynamic, rather than static.  To help us survive, our eyes are biological machines which enable us to detect motion, distance, and colors so that we can see predators and food and are able to eat rather than be eaten.  Vision is a dynamic process inherent in all animals.

 

Visual acuity is the term used to describe the clarity of how well you see.  A refraction is the process of using special lenses for measuring the sphere, cylinder, and axis optical variables which go into creating eyeglasses and contact lenses to compensate for “less than perfect” vision.  Typical vision tests use static letters or symbols as the standard targets for measuring vision.  The flaw with static measurement systems is that they are typically only two dimensional using the height of the visual target and the viewing distance to that target.  Instead, the world we see (the “real world”). is a fifth dimensional process consisting of height, width, colors, distance, and time.

 

A Dyop® (pronounced “di-op”) is a calibrated segmented spinning ring visual target (aka, optotype) which helps doctors (and you) test how clear your vision is.  A Dyop provides a strobic stimulus to the photoreceptors in the center rear area of the retinal of your eye called the fovea.  (See the illustrations and details below). 

 

Dyop testing is better than vision testing methods which use letters (aka, the 1862 Snellen “Big E” test) or other static shapes because it is based on how your eyes work.  As the Dyop diameter gets smaller, its alternating gaps and segments get proportionately smaller.  When the spinning Dyop gaps get sufficiently small, the stimulus area of each gap is smaller than the minimum AREA to stimulate the color-receptive photoreceptors in the rear (fovea) area of the retina, which are clusters of about 20 color-receptive photoreceptors.  When the Dyop gaps become too small to stimulate the clusters of photoreceptors, the perception is that spinning of the Dyop ring is not detected because the stimulus of the gaps and segments tend to merge.  A Dyop NOT detected as spinning has a “sub-acuity” diameter.  As the Dyop diameter is increased to enable the gaps to stimulate a minimum of 20 fovea photoreceptors, that minimum Dyop diameter where spinning IS detected is the Acuity endpoint.  That minimum size threshold for detecting the gaps as spinning is also called the Minimum AREA of Resolution (MAR).  (The biggest flaw in previous acuity testing, and acuity “standards” when using letters is that Snellen viewed acuity as a two-dimensional, letter height and viewing distance, problem and mistakenly called it the “Minimum ARC of Resolution”.)

 

The result of using a Dyop for acuity and refractions is that a Dyop is up to three times more efficient than 1862 static Snellen letter-based tests (which also uses culturally dependent Recognition Acuity static letters or symbols), up to six times more precise, and up to eight times more consistent.   A Dyop also can measure acuity regardless of the subjects’ literacy skills or culture, and easily enables testing of children or infants, and enables measurement of acuity in color for potential diagnostic and/or therapeutic use.

 

Static vision tests (e.g., Snellen) are based on how well you recognize culturally dependent letters or symbols, are influenced by where you're from, or how much you've practiced (or memorized).  Using a Dyop makes vision testing simpler, faster, more precise, and more consistent.

 

= = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = =

 

Sample Dyop Tests

 

Online Dyop Visual Acuity Test

Open the acuity (visual clarity) test with the above link.  Note the smallest pair of Dyop rings you can detect as spinning.

View the spinning rings at a five-foot distance.

The center row of numbers between the smallest pair of rings you can detect as spinning rings

is the measure of your acuity.

 

(Below are static images of the Dyop online Acuity test.)

Dyop acuity screening test for use at 5 feet                   Dyop acuity screening test for use at 10 feet

 

            

            

Online Dyop Color Screening Test

Open the acuity (visual clarity) test with the above link.  View the spinning rings at a five-foot distance.

The smallest colored Dyop ring (Blue/Black or Green/White) you can detect as spinning indicates your color acuity profile.

The row of numbers below the smallest colored ring you can detect as spinning is the measure of your color acuity.

Preferentially seeing the smaller Blue/Black rather than the Green/White indicates a probability

of symptoms of dyslexia, migraines or epilepsy.

 

Dyslexia and Color Perception

https://www.dyop.net/documents/Dyslexia_and_Color_Perception-SandraStark.pdf

 

Color Perception as a Diagnostic

https://www.dyop.net/documents/ASOP-06-0651-Dyop_Color_Perception.pdf

 

Advances in Dyslexia Management

https://www.dyop.net/documents/Advances in Dyslexia Management.pdf

 

(Below are static images of the Dyop online Color Screening tests.)

                          Dyop Blue/Green Visual Screening Test at 5 feet

Dyop Blue/Green Visual Screening Test at 10 feet

                              

 

 

 

= = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = =

 

Dyop Visual-Impairment Test

A Dyop may also be used to evaluate the visual/mental impairment associated with conditions such as marijuana intoxication, PTSD, concussion injuries, and other possible mental difficulties such as Alzheimer’s.

 

https://www.dyop.net/documents/Dyop_Visual-Impairment_Test-x10.swf.html

Use the link above to open the Dyop Visual-impairment test.

Note that THIS is a Timed Test.  Click the word “Start” at the top of the test to begin.

Additional details are at:  https://www.dyop.net/impairment.htm

(Below is a static image of the initial screen for the Dyop Visual-Impairment Test.)

 

Note that when the test starts, there will be FIVE Dyops on the screen but only ONE of them is spinning.

Use a computer mouse or touch screen to click the arrow adjacent to the SINGLE spinning Dyop to indicate its spin direction. That Dyop will stop spinning, but ONE of the other FOUR Dyops will then start spinning.

Click the arrow adjacent to that next spinning Dyop to indicate its spin direction.

 (Below is a static image of the response screen for the Dyop Visual-Impairment Test.)

 

When you have found and detected all TEN of the spinning Dyop test response trials, the screen will

display the number of Correct Selections and the elapsed Test Time.

A test completion time of 14 to 16 seconds with 10 correct responses indicates mental alertness.

A test completion time of 21 to 26 seconds with less than 10 correct responses indicates minor mental impairment.

A test completion time of 28 to 32 seconds with less than 8 correct responses indicates increased mental impairment.

A test completion time of 35 to 40 seconds with less than 6 correct responses indicates significant mental impairment.

(Below is a static image of a final response screen for the Dyop Visual-Impairment Test.)

 

= = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = =

What Regulates Acuity

 

For vision to be effective and efficient, it needs to be autonomic (so that we are unaware of that process).  However, acuity is NOT regulated by the brain.  As light goes through the cornea and lens, it is bent so that Blue is focused in FRONT of the retina, Green is focused ON the retina, and Red is focused BEHIND of the retina.  (See the diagram below.)  Acuity is regulated by the relative focal depths and intensity of those colors as they are perceived by the color sensitive photoreceptors in the fovea at the back of your eyes.  Those color sensitive photoreceptors then send their signals forward to the layer of neuroganglia in front of the retina. That neuroganglia layer of cells then sends a signal to the lens to regulate the shape of the lens to bring that image into focus.

 

The process of combining the response of the color-sensitive photoreceptors to light and color is like the pixel images you see on your computer monitor, tablet, or Smartphone.  You think you are seeing lines, shapes, letters, and/or words.  What you really are seeing are pixels of light moving rapidly across the surface of your computer screen, tablet, or Smartphone in combinations of RedGreen, and Blue.  This process of acuity regulation and accommodation is called Chromatic Triangulation.

 

 

Chromatic Triangulation is based on the concept of the refraction of light that Isaac Newton discovered in 1665 when he filtered light through a prism.

Dyslexia and Color Perception

https://www.dyop.net/documents/Dyslexia_and_Color_Perception-SandraStark.pdf

 

Color Perception as a Diagnostic

https://www.dyop.net/documents/ASOP-06-0651-Dyop_Color_Perception.pdf

 

A simple experiment to demonstrate that acuity is regulated by the Chromatic Triangulation of RedGreen, and Blue, rather than by the brain, is to close one eye and look around the room where you are now.  You will notice that with only one eye open you can still determine the relative distance to nearby objects without the need for binocular vision.

 

= = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = =

 

How Acuity is Measured

 

The properties of visual clarity (acuity) are the SIZE (area) OF THE IMAGE being observed, the VIEWING DISTANCE to that image, and the ability of the visual system to PROCESS THAT IMAGE as clearly as possible (Resolution Acuity).  As a Dyop® spinning ring gets smaller, the (equally sized) gaps and segments become so small that it becomes impossible (sub-acuity) for the eye to detect the spin direction of the Dyop ring rotation.

 

The Dyop acuity endpoint is the smallest Dyop diameter where the direction of rotation of the spinning ring can still be detected.  It serves as a precise, physiological indicator of visual clarity and vision correction.  A Dyop test can measure vision without the need for patient literacy, measure vision in infants as young as 14 months of age, and let doctors precisely measure vision in color enabling potential diagnostics for symptoms of dyslexia and glaucoma.

 

 

 

 

A close up of a chartDescription automatically generated

 

 

 

 

 

 

 

 

 

 

 

 

A black and white poker chipDescription automatically generated

 

 

A black and white poker chipDescription automatically generated

 

 

A black and white poker chipDescription automatically generated

 

 

 

 

20/22

 

 

20/20

 

 

20/18

 

1862 Snellen Vision Testing

Dyop Diagram

21st Century Dyop® Vision Testing

 

Static acuity tests (such as Snellen letters) are inherently imprecise, inconsistent.  They mistake the process of visual cognition for visual resolution and have an overly large stimulus area (1.0 arc minutes squared) as the benchmark vision rather than the empirically determined smaller Dyop stimulus gap area (0.54 arc minutes squared).  Additionally, static vision tests such as Snellen deplete the dynamic response of the color receptive photoreceptors in the fovea and lack the uniform precision of Dyop testing.  The result is that static vision tests tend to add excess minus power to acuity and refractions, lead to angular elongation of the eye and increased myopia and indicate that Snellen testing may be a factor in the Global Epidemic of Myopia.

https://www.dyop.net/documents/Snellen_vs_Dyop_Refractions-Sanni.pdf

https://www.dyop.net/documents/ASOP-2022-01_Sanni-update.pdf
https://www.dyop.net/documents/JCOVS-21-Gordon_refraction_comparison.pdf
https://www.dyop.net/documents/Guy_Barnett-Itzhaki_The_Dynamic_Optotype.pdf

 

A simple test to verify that your lenses are too strong (with too much minus power IF you wear glasses), is to push your glasses about a half inch away from your face and see if the words you are reading become larger and more legible.  If you notice that the words get more legible, that Snellen-induced excess minus power of your glasses is typically about 0.25 to 0.50 diopters.  While it isn’t much, it does reduce your cognition and possibly your IQ by 10 points.

 

= = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = =

 

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, Johns Creek, GA, 30022   /   404-281-7798

Copyright ©2025 DyopVision™ Associates.  All Rights Reserved.