Dyop® - Dynamic Optotype™

Helping the world see clearly, one person at a time




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How it works


Visual Impairment






Is 1862 Vision Technology Making

21st Century Patients Blinder?


Introducing the "revolutionary" Dyop® for measuring vision


Dyop® (short for dynamic optotype) is spinning segmented ring which provides a kinetic strobic stimulus of the photoreceptors for use as a visual target (optotype).


Dyop Vision Webpage






Dyop Video





   Dyop Strobic Stimulus



Twenty first century technology is letter-based technology.  Today’s visual acuity is primarily measured by the clarity and ability to read text on an electronic display.  Unfortunately, vision science has not kept up with the more precise demands of 21st century visual needs, and vision tests using static visual targets tend to be unnecessarily imprecise and inconsistent.


A novel highfrequency visual acuity chart


"Results confirm the arbitrary nature of the Snellen fraction and warn about the accuracy of visual acuity determined by using charts of different letter types, calibrated by Snellen's system."


The Dyop strobic stimulus has greater precision and less variance than static visual targets



The increased precision and consistency and “resolution acuity” of Dyop tests are intended as a global replacement for static letter-based “recognition acuity” tests such as Snellen, Sloan, and Landolt optotypes, and can provide a more universal and efficient method of vision measurement.


The world we see is dynamic rather than static.  As a result, using of static visual targets to measure vision depletes the response of the photoreceptors, is inherently imprecise and unnecessarily inefficient, and tends to produce an overminused (excess spherical power) refraction.  Keeping vision dynamic requires the kinetic energy of the saccade process for you to see.  The saccade process functions much as the scanning lines of the pixels of your computer monitor to keep the image from burning into the screen.  That kinetic energy of the saccade process allows the photoreceptors to be constantly refreshed, adjust for changes in visual focus and color, and avoid photoreceptor fatigue from static stimuli.

Static visual targets (optotypes) deplete that photoreceptor response, and are inherently imprecise and inconsistent.


Dyop Basics


1.  The world we see is dynamic which is why static vision tests are inherently imprecisely. 

2.  The world we see is usually in color.  Testing vision only in black and white ignores most human perception.

3.  Our view of the world is determined by how we see the world.  Imprecise acuity reduces productivity and increases cultural gullibility.


Introducing the Dyop


Dyop® (short for dynamic optotype) is spinning segmented ring which uses resolution acuity, and provides a kinetic strobic photoreceptor stimulus for use as a visual target (optotype).  The precision of the strobic Dyop stimulus functions much as a visual tuning fork to precisely, consistently, and efficiently benchmark your visual clarity (acuity).  The motion of the Dyop gaps and segments of the spinning ring create a strobic binary stimulus of the photoreceptors of your eye.  When the gap/segment stimulus area of a spinning Dyop gets too small (as the Dyop ring appears to become smaller), that strobic visual gap/segment stimulus area is too small for the photoreceptors to detect that apparent gap/segment motion.  The smallest diameter Dyop ring where the gaps/segments direction of spin can be detected serves as a benchmark of acuity (visual clarity) and can be used to determine refractions.  It also allows for the precise measurement of visual acuity in color.



Dyop Components

Item 1 – visual angular velocity or strobic contrast response

Item 2 –a moving segment visual arc-area dynamically stimulating retina cells with motion

Item 3 –retinal cell clusters

Item 4 – an example of a static historical optotype (Snellen/Landolt)

Item 5 – a static minimum angle/area of resolution of a historical optotype



In the 21st century, the smallest diameter Dyop ring whose gaps/segments are detected as spinning serves to precisely benchmark acuity (visual clarity), and can be used to determine refractions regardless of culture or literacy.


1862 Snellen Vision Testing


21st Century Dyop® Vision Testing


























The Mechanics of Vision 


Your eyes developed to detect motion and function similar to the pixels receptors of a computerized video camera.  As you read these words you have the illusion that you are seeing lines and shapes and letters.  What you are actually seeing are pixels of light generated by electronic phosphors within the surface of your computer screen.  However, those electronic pixels are perceived by the photoreceptors of the retina in the back of your eye.  Those photoreceptors in your retina respond to light as biological pixels.  Those biological photoreceptor pixels combine their response (primarily to the colors red, green, and blue) into giving you the perception of vision. 


The eye’s photoreceptors not only allow you to see in color, but the refresh rate of the photoreceptors combines with the strobic saccade process to create a matrix response to color-perception which allows the photoreceptors to track changes in the location of those images.  The saccade process functions much as does the scanning lines of the pixels on your computer monitor to keep the image from burning into the screen.  The response of about 100 photoreceptors combines to create the stimulus for each optic nerve fiber going to the brain which creates vision and brings that image into focus.  However, the neural ganglia layer of the retina “process” those photoreceptor responses in clusters of about 20 photoreceptors much as a biological circuit board with the emphasis on patterns of motion and proximity.  The comparative focal depth of the colors red, green, and blue of the images also regulates the shape of the biological lens and adjusts focal clarity.


Light passes through the lens

to reach the retina

Retina Structure

 4 Neural Layers

Photoreceptors as Pixels

Retina Color Perception

Wavelengths of light









Light => => Perception

The impetus for survival is what gave your eyes a preference for detecting motion.  That preference is illustrated when you fixate on the Plus (+) in the circle image below.  As you fixate on the Plus (+) you will likely see a moving Green circle which appears as the Pink circles seem to rotate around that Plus.  The moving Green circle appears because of the strobic photoreceptor refresh rate, the depletion of the Red photoreceptors, and their depleted ability to respond to the color Red in the Gray background. 



A strobic stimulus lets you sense your pixelized response to the images you are seeing.


The Lilac Chaser Illusion



Fixate on the + in the center of the spinning pink dots and notice that the moving gray area becomes a green dot due to photoreceptor depletion.



The Lilac Chaser Illusion




The History of Vision Measurement


Thousands of years ago, visual clarity (acuity) was defined by the ability to see the nighttime gap between two of the smaller stars in the handle of the Big Dipper constellation.


Stellar Acuity

Static Letter-based Acuity

Dyop Strobic Acuity


In 1862 Dutch Ophthalmologist Herman Snellen used the ability to identify (European) letters as a benchmark for visual acuity.  By then, reading had become a dominant economic and social skill in Europe.  Snellen used the convenience of black letters on a white background as his benchmark, although most of what we see is NOT in black and white, and other cultures use pictographs rather than letter-based words. 











In an era where SmartPhones and computers are ubiquitous, the

inherent errors of the Snellen test are no longer acceptable. 


21st century vision needs can no longer rely on 1862 technology


Your eyes are biological machines which developed as sensors for detecting motion, distance, and colors to enable us to detect predators and game and so that we can eat rather than be eaten.  


To be able to see, your eyes use the kinetic energy of the visual saccades and the refresh rate of the photoreceptors.  To see efficiently, vision also is an autonomic process.  We are usually totally unaware of the mechanics of that process. 


Current global vision “standards” are based upon “recognition acuity” and the 1862 cultural skill of being able to detect the identity and size differences between static letters, such as “E” and “C.” 


As a result, that 1862 Snellen method is dependent upon cognition and culture, and improperly and imprecisely measures vision. 


The Dyop uses the physiology of the eye and “resolution acuity” to more precisely (6x), more consistently (6x), and more efficiently (4x) measure vision.









The personal use of the Dyop test is intended to only measure visual clarity.  A PRESCRIPTION for glasses or contact lenses requires vision testing and a refraction performed by an eye doctor because it CANNOT be done on a two-dimensional display such as a computer. 


You can measure your vision with the Dyop test using the Dyop Personal Acuity Test. 


If you can’t see clearly enough, GO SEE YOUR EYE DOCTOR.


Dyop® tests are for vision screening purposes only and are NOT a substitute for an examination by a licensed vision care professional. 




“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   /   404-281-7798

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