This document presents 6 optical illusions designed by students to test visual acuity and its uses in the military. Each illusion is explained in terms of how it exploits visual perception mechanisms like depth perception, motion perception, and size constancy. The illusions use techniques like contrasting colors, shapes arranged to imply depth, and dilation to trick the eye. The document argues the illusions could help train soldiers to identify camouflaged objects and evaluate distances/motion, as well as potentially camouflage military aircraft and ships.

1. Optical Illusions Project
By: Jacob Nixon, Darsh Patel, Luke Babilon, and
Conner Steenrod

2. Background: Visual Acuity and its uses
in the US military
Visual acuity is the sharpness of one’s vision, measured by the ability to recognize
letters, numbers, or patterns from a certain, standard distance. The clearness and
acuteness of vision is determined by optical and neural factors such as the retina and
interpretive abilities of the brain.

3. Background: Visual Acuity and its uses
in the US military
Visual acuity tells how good someone’s eyesight is
by measuring how well someone can discern an
optotype (a letter or ring with a cut-out) from 20 feet. A
person with 20/20 vision has normal vision: they see an
image normally from 20 feet away. A person with 20/40
vision has bad vision (they see an image that a person
with 20/20 would see from 40 feet away) while a person
with 20/10 vision has extremely good vision (they see an
image that a person with 20/20 vision would see from 10
feet away).

4. Background: Visual Acuity and its uses
in the US military
Testing acuity can involve looking at a poster with different letters, shapes, dots,
and lines from a certain distance away (20 feet). Another way to test a person’s acuity
is by looking at an optical illusion and seeing how they describe it.
The military uses visual acuity and optical illusions to create aircraft that
camouflage in sky. The military also trains soldiers to be able to identify camouflaged
aircraft and landmines and trains pilots to identify far-off or camouflaged ships and
aircraft that may be ready to attack.

5. Why our designs are the best
Our designs incorporate certain colors and patterns that cause the brain to
send messages to the eyes that are different than what the eyes are actually seeing,
which confuses the brain. These messages include the organization of the brain to make
something meaningful, the perception of depth and motion, color and brightness
constancy, and object consistencies. Using our brains need to making something that
doesn’t make sense logical, optical illusions - such as our’s - can effectively trick the
untrained eye into seeing something that may not actually be there.

6. Optical Illusion #1
How many cubes are in the picture?
How about now?

7. Our first optical illusion takes advantage of the brains need to create depth and
have a meaningful light source. We chose two contrasting colors - black and white -
and grey to create the effect of depth on a 2-D surface. We also tessellated black
squares, grey parallelograms, and white parallelograms by translating them to form
hexagons, that were, themselves, translated. This shapes create the illusion of cubes
(depth) on paper. This design tests visual acuity because it tests to see if you can see
the changing number of cubes. If your brain didn’t create the false perception of depth,
it would simply look like a tessellation. It also tests your brains ability to change
perspective. This is important in the military because as objects get closer or farther, a
soldier may need to change his perspective quickly so that they can focus on what is
going in front of them and avoid injury (for example changing perspective from
riflemen in the distance to one that has charged in front of you).
Optical Illusion #1 Explanation

8. Optical Illusion #2

9. Optical Illusion #2 Explanation
This illusion takes advantage of the brain’s depth perspective. The lines are
actually equal in height, but to the average eye the one on the right looks taller. This is
because of the background. The lines in the background make it look like you are
looking at the picture at a angle, and the one on the right is farther away. Take the lines
away, and you have two parallel lines of the same height and width. This could help
the army in visual acuity testing and help give soldiers the opportunity to see through
depth illusions and be able to master the art of hiding enemy spotting. The colors used
were black and white (they are contrasting colors that help create the mirage of depth)
and the design includes two boxes (one was translated to the spot of another), slanted
lines that gradually get bigger (dilation), and two end lines that are also dilations. The
shapes help create a sense of depth and distance.

10. Optical Illusion #3

11. Optical Illusion #3 Explanation
This design uses depth and perspective to create two distinct figures that have
different fronts. The colors used here were black and white - contrasting colors that
help create depth - and the rectangles and parallelograms were translated to make the
illusion of a rectangular prism. We chose these colors (specifically the empty
rectangles) and design because when you focus on one particular rectangle (the top or
bottom) the image “shifts” and the one you are looking at becomes the front. This can
be used to test a person’s visual acuity by seeing how they are able to change
perspectives. It can also train a soldier’s ability to determine how an object is angled
and which way it will move.

12. Optical Illusion #4
Are the lines
bent, slanted,
or rounded, or are
the sizes
changing? Is there
any movement?

13. Optical Illusion #4: Explanation
Our fourth optical illusion uses the fact that although the brain is fast but it can not
process a complex image fast enough therefore creating confusion. We chose black
and white, two colors that contrast, which causes light to irradiate from the black lines
to the white trapezoids. The shapes (trapezoids that were glide reflected and translated
to form columns of trapezoids) create the illusion of the lines being bent and the
trapezoids moving because of how they are staggered . The use of congruent shapes
and contrasting colors (irradiation) causes the lighter objects to appear larger. As you
focus on one set of trapezoids, the others appear smaller, so as you readjust your
perspective, the “large” column appears to move, thus you identify motion in the
trapezoids and bending of the lines. This can help train soldier’s visual acuity and
ability to determine how an object is moving and if it is moving at all.

14. Optical Illusion #5
Is the circle going in or
coming out?

15. Optical Illusion #5: Explanation
Our fifth illusion manipulates the brain’s need to create depth using contrasting
colors. The contrasting colors - black and yellow - creates the illusion of depth. We
also used dilating circles to further play on the creation of an illusive depth (they make
it appear like the 3-D image is going further away from you or coming towards you and
tapering to a point). Visual acuity is important here because depending on how far
away you are and how you look at this, you will see something different each time. It
can also train military soldiers to be able to tell what direction an object is moving
under the most confusing of situations.

16. Optical Illusion #6
Which inner circle is
bigger?

17. Optical Illusion #6 Explanation
On our sixth and last illusion, we used a very simple concept and turned it into a “mind
twister.” We used two colors: red and yellow; red is put on a plain yellow background,
which helps create a difference in size between the centers because there are no lines or
other objects to give away the equality. The reason we chose this image is because it
incorporates dilations which can be very powerful to trick the eye when used right and
rotations of larger/smaller objects that bolster the size of the inner circles. By using the
dilations to change the size of the outer hexagons, we controlled the brain’s need to
make something logical - since smaller hexagons are surrounding one hexagon and
bigger ones the other, the former appears to be larger than the latter, similar to how a
person looks huge compared to an ant but tiny compared to a building. This can help
test and train visual acuity by seeing if the viewer can see the equality of the two
hexagons. With this, a soldier could pick out the size of an object even if it surrounded
by smaller or larger objects.

18. How our designs can be incorporated into the
military
Our designs can be used by the military in two ways. The first is to use for
training soldiers to be able to spot and eliminate similar illusions and to test how well
they can see illusions from a certain distance away. This could help soldiers find
landmines, camouflaged planes or ships, or find possible traps in the environment
around them. The second is to use them on our planes and ships to camouflage them,
or we can make dummy planes that are distracting enough to take the enemy’s attention
of the real plane or ship. For example, if a dummy plane was positioned right it could
make it appear as though the real plane were moving closer or further away. These
reasons are why our designs should be used by the military.