Tunnel Illusion

Tunnel Illusion

This cool tunnel illusion that creates the illusion of a 3D tunnel or a concave shape that moves slightly despite the fact that the image is completely flat.

If you are interested about how this cool tunnel illusion works, scroll down to readmore about it.

Tunnel Illusion


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What is the Tunnel Illusion?

The tunnel illusion is an optical illusion that creates the illusion of a tunnel or a concave shape when, in fact, the image is completely flat.

The black and white checkerboard pattern is often used to create this illusion. In this version of the illusion, the checkerboard pattern is placed on a flat surface and the pattern is manipulated so that the squares appear to be getting smaller as they get further away from the viewer. This creates the impression of a tunnel or a concave shape that appears to be extending into the distance.

The illusion works because of the way our brains interpret depth cues. As objects get further away, they appear smaller, and our brains use this information to interpret the size and shape of objects in the world. By manipulating the size of the squares in the checkerboard pattern, the illusion tricks our brains into perceiving a depth that isn’t actually there.

How does the Tunnel Illusion Work?

The tunnel illusion works by exploiting our brain’s perception of depth and perspective. When we look at an image that includes converging lines or patterns, our brain naturally interprets those lines as representing depth or distance. In the case of the tunnel illusion, the black and white checkerboard pattern is arranged in such a way that the squares appear to be getting smaller as they recede into the distance. This creates the impression that the image is actually a tunnel or a concave shape, when in reality it is just a flat image.

Our brain relies on many different cues to interpret depth and distance, including binocular disparity (the difference between the images received by our two eyes), motion parallax (the way objects appear to move at different rates when we move our head or eyes), and perspective (the way objects appear smaller when they are further away). In the case of the tunnel illusion, perspective is the key cue that tricks our brain into perceiving depth and distance.

When we look at the tunnel illusion, our brain automatically interprets the converging lines of the checkerboard pattern as representing a tunnel or a concave shape, even though we know intellectually that the image is flat. This is because our brain is wired to interpret certain patterns as representing depth and distance, and the checkerboard pattern used in the illusion is a particularly effective way of exploiting this wiring.

Some Similar Illusions

There are many other optical illusions that are similar to the tunnel illusion, in that they exploit our brain’s perception of depth and distance to create a false sense of three-dimensionality. Here are a few examples:

  1. Ames Room illusion: This illusion creates the impression of a room that is longer or shorter than it actually is. It works by using forced perspective, where one side of the room is closer to the viewer than the other. This makes objects and people in the room appear to be larger or smaller than they actually are.
  2. Ponzo illusion: This illusion creates the impression that two identical lines are different lengths, based on their context. The illusion works by placing the lines in the context of converging lines that suggest depth, which causes our brain to interpret the top line as being further away than the bottom line.
  3. Mueller-Lyer illusion: This illusion creates the impression that two identical lines are different lengths, based on the presence of angled lines at the ends of the lines. The illusion works because our brain interprets the angled lines as indicating perspective, and assumes that the line with the outward-angled lines is further away and therefore longer. The Müller-Lyer illusion was first described by Franz Carl Müller-Lyer in 1889.
  4. Hering illusion: This illusion creates the impression that two parallel lines are curved, based on the presence of converging or diverging lines around them. The illusion works by exploiting our brain’s tendency to interpret certain visual patterns as representing depth and perspective.

These are just a few examples of the many optical illusions that are similar to the tunnel illusion in their use of depth and perspective cues to create a false sense of three-dimensionality.

Discovery of the Tunnel Illusion

The tunnel illusion has been studied by many researchers over the years, and it’s difficult to attribute its discovery to any one person. However, one of the earliest known examples of the tunnel illusion can be found in a 1904 book called “The Psychology of Special and Differential Diagnosis of Malingerers” by Dr. William Hirsch, a German ophthalmologist.

Hirsch included an illustration in his book that featured a black and white checkerboard pattern arranged in a way that created the illusion of a concave tunnel. Although Hirsch did not describe the illusion in detail or conduct any experiments to study it, his illustration is one of the earliest known examples of the tunnel illusion.

Since Hirsch’s time, the tunnel illusion has been studied and discussed by many other researchers, including psychologists, neuroscientists, and vision scientists. It has been used as a tool for understanding how our brains process visual information, and it continues to fascinate and intrigue scientists and laypeople alike.


References and Resources

In addition to the Tunnel Illusion, check out our complete list of illusions.

Chromatic Rainbow Illusion

Chromatic Aberration Illusion

If you squint at this Chromatic Rainbow Illusion, you will see a rainbow like effect between the red and white lines due to chromatic aberration.

Chromatic aberration occurs when different colors of light refract at different angles, causing the image to appear blurred or distorted. In the case of this illusion, Chromatic aberration occurs when red lines are placed against a high-contrast white background, causing the viewer to perceive a rainbow-like effect along the edges of the red lines. This illusion is a result of the way our eyes perceive and process different colors of light.

If you are interested in learning more about the Chromatic Rainbow Illusion, scroll down to read more about it.

Chromatic Aberration Illusion


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What is the Chromatic Rainbow Illusion?

The chromatic aberration illusion occurs when different colors of light refract at different angles causing the image to appear blurred or distorted. In the image above, it occurs when red lines are placed against a high-contrast white background, causing the viewer to perceive a rainbow-like effect along the edges of the red lines. This illusion is a result of the way our eyes perceive and process different colors of light.

How does the Chromatic Rainbow Illusion Work?

The illusion works due to chromatic aberration, an optical phenomenon that occurs when different colors of light refract differently as they pass through a lens or other optical element. This causes the colors to focus at slightly different points, leading to blurred or distorted images.

To understand how chromatic aberration works, it’s important to first understand how light interacts with lenses. When light passes through a lens, it is refracted, or bent, as it changes speed. This refraction causes the light to converge, or come together, at a focal point.

However, different colors of light have different wavelengths, which means they bend at slightly different angles as they pass through a lens. This causes the different colors to focus at slightly different points, creating a blurred or distorted image with a rainbow-like halo around the edges.

Some Similar Illusions

Here are some other optical illusions similar to the Chromatic Rainbow Illusion that you might find interesting:

  1. This Chromatic Adaptation Illusion allows you to see a black and white image in full color.
  2. Chromostereopsis is an optical illusion that involves the perception of depth and three-dimensionality based on color information. It is caused by the differential refraction of light of different wavelengths, known as chromatic aberration, as it passes through a lens.
  3. The Bezold Effect is a phenomenon in color theory where a change in one color can cause the perception of the surrounding colors to change as well.
  4. Moiré patterns: These are patterns that appear when two overlapping patterns with slightly different frequencies or orientations are superimposed.
  5. Color Afterimages: After staring at a bright color for a period of time, you might see an image of that color when you look away.
  6. Stereograms: Stereograms use a combination of two images that are slightly offset from each other to create the illusion of depth.
  7. Binocular rivalry is a phenomenon that occurs when slightly different images are presented to each eye simultaneously.
  8. Troxler’s fading, is a phenomenon in which a stationary visual stimulus eventually disappears from perception, even though it is still present in the visual field.
  9. The Scintillating Grid Illusion, in which a grid of black and white squares appears to pulsate or “breathe” when viewed from the periphery of the image.
  10. Silencing is a visual phenomenon where objects that change in luminance, hue, size, or shape appear to stop changing when they move. They “freeze” in place.

Discovery of the Chromatic Rainbow Illusion

The phenomenon of chromatic aberration which underpins the Chromatic Rainbow Illusion was first described and analyzed by the English scientist Sir Isaac Newton in the 17th century. Newton conducted experiments with light passing through prisms and lenses, and he found that the different colors of light were bent at different angles as they passed through the prism or lens, causing them to focus at different points.

In his book “Opticks,” published in 1704, Newton presented his findings on chromatic aberration, along with his theory of light and color. He also proposed a solution to the problem by suggesting the use of lenses made of two different types of glass with different refractive indices.

Since then, many advancements have been made in the correction of chromatic aberration, with the development of specialized lenses and lens coatings that are designed to reduce or eliminate this optical aberration.


References and Resources

In addition to the Chromatic Rainbow Illusion, please check out our complete list of illusions.

Moving Spiral Illusion

Moving Spiral Illusion

Look at the center of this Moving Spiral Illusion and watch as the surrounding circles appear to spiral around the center.

This Moving Spiral Illusion works based on the principles in two famous illusions – the Fraser Spiral and Peripheral Drift.

If you are interested in learning more about how this Moving Spiral Illusion works, scroll down to read more about it.

Moving Spiral Illusion


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What is the Moving Spiral Illusion?

This Moving Spiral Illusion works based on the principles in two famous illusions – the Fraser Spiral and Peripheral Drift.

The Fraser spiral illusion is an optical illusion that involves a spiral pattern composed of concentric circles.

In the Fraser spiral illusion, the individual circles appear to spiral outward towards the edges of the pattern, giving the impression of a continuously expanding spiral. However, in reality, the circles are arranged in a series of disconnected concentric circles, with no actual spiral present.

The illusion occurs due to the way our brain processes visual information. The concentric circles and spacing between them create an optical effect that leads our brain to perceive a spiral where there is none. This is an example of a perceptual illusion, where our perception of reality is altered due to the way our brain processes information.

Peripheral drift is an optical illusion that occurs when stationary patterns, such as stripes or grids, appear to move or “drift” in the peripheral vision of an observer. The illusion is created by the way the brain processes visual information from the retina, which can cause the edges of the patterns to appear to blur or vibrate slightly.

The effect is more pronounced when the patterns are high-contrast, such as black and white stripes, and when the patterns are presented in the periphery of the visual field. The illusion can be enhanced by adding motion to the patterns or by varying the width or spacing of the stripes.

Peripheral drift is thought to be caused by a combination of factors, including the way the brain processes spatial frequency information, the interactions between adjacent visual neurons, and the effects of eye movements and fixational eye movements.

Peripheral drift is a well-known phenomenon in vision science and has been studied extensively as a way to better understand the mechanisms of visual processing in the brain.

How does the Moving Spiral Illusion Work?

This Moving Spiral Illusion works based on the principles in two famous illusions – the Fraser Spiral and Peripheral Drift.

The Fraser spiral illusion works by exploiting the way our visual system processes information. The illusion is created by a pattern of concentric circles that are spaced closer together near the center of the spiral and farther apart towards the outer edges.

When we look at the pattern, our brain tries to make sense of the visual information by grouping the circles into patterns. However, because the spacing between the circles changes, our brain interprets the pattern as a spiral rather than a series of concentric circles.

The illusion is further strengthened by the fact that the circles are shaded so that they appear to have a gradient of darkness from the center to the outer edge. This gradient reinforces the impression of a spiral, as our brain interprets the change in shading as indicating a continuous curve.

In short, the Fraser spiral illusion is created by manipulating the visual cues that our brain uses to interpret patterns, leading us to perceive a spiral where none actually exists.

Peripheral drift is an optical illusion that occurs when stationary patterns, such as stripes or grids, appear to move or “drift” in the peripheral vision of an observer. This illusion is caused by the way the brain processes visual information from the retina.

The retina is the part of the eye that receives visual input from the environment and sends it to the brain for processing. The retina is made up of cells called photoreceptors, which detect light and send signals to other cells in the retina, called retinal ganglion cells.

The retinal ganglion cells are organized in a way that allows them to detect different aspects of the visual scene, such as edges, color, and motion. Some cells are sensitive to low spatial frequencies, meaning they respond best to wide, low-contrast patterns, while others are sensitive to high spatial frequencies, which means they respond best to narrow, high-contrast patterns.

When an observer views a stationary pattern of high-contrast stripes in their peripheral vision, the edges of the stripes appear to blur or vibrate slightly due to the interactions between adjacent visual neurons in the retina. These slight movements are then interpreted by the brain as motion, which creates the illusion of drifting.

Additionally, eye movements and fixational eye movements, which are small involuntary movements of the eyes, can also contribute to the perception of drifting. As the eyes move and fixate on different points in the visual scene, the edges of the patterns can shift slightly, which can enhance the illusion of movement.

Overall, peripheral drift is a complex phenomenon that involves multiple factors in both the retina and the brain. Studying this illusion can provide valuable insights into the mechanisms of visual processing and perception.

Discovery of the Moving Spiral Illusion

This Moving Spiral Illusion works based on the principles in two famous illusions – the Fraser Spiral and Peripheral Drift.

Sir James Fraser was a British psychologist who made important contributions to the field of perception and cognitive psychology.

He was born in 1854 and died in 1941. He is best known for his work on visual perception, particularly for his description of the Fraser spiral illusion in 1908.

Fraser studied at Cambridge University and later became a professor of psychology at University College London.

He made a significant contribution to the study of visual perception, and his work on the Fraser spiral illusion helped to establish the field of cognitive psychology, which focuses on how the brain processes and interprets information.

He also made contributions to other areas of psychology such as memory and attention. He was knighted in 1935 for his services to psychology.


References and Resources

In addition to the Moving Spiral Illusion, check out our complete list of illusions.

Hyperboloid Optical Illusion

Hyperboloid Optical Illusion

These Hyperboloid Optical Illusions involves a sphere appearing to rotate around a hyperboloid, when in fact the objects are all static.

The illusion is created by placing a static ball at the center of the hyperboloid shape, which is typically drawn or displayed on a two-dimensional surface. As the viewer moves their gaze around the shape, the ball appears to move along the hyperboloid in a smooth and continuous motion, even though it is actually stationary.

If you are interested in learning more about Hyperboloid Optical Illusions, scroll down to read more about it.

Hyperboloid Optical Illusion
Hyperboloid Optical Illusion


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What is the Hyperboloid Optical Illusion?

The Hyperboloid Optical Illusion creates the appearance of a static ball moving around a three-dimensional hyperboloid shape, which is a surface that has two curved branches that are connected like an hourglass.

The illusion is created by placing a static ball at the center of the hyperboloid shape, which is typically drawn or displayed on a two-dimensional surface. As the viewer moves their gaze around the shape, the ball appears to move along the hyperboloid in a smooth and continuous motion, even though it is actually stationary.

This illusion works because the hyperboloid shape creates the perception of depth and movement, which tricks the brain into perceiving the static ball as moving. It is a popular optical illusion that has been used in art, design, and visual effects in movies and video games.

How does the Hyperboloid Optical Illusion Work?

The Hyperboloid Optical Illusion that makes a static ball appear to move around a hyperboloid works by exploiting the way our brains perceive depth and motion.

When we look at an object, our brain processes the visual information it receives and creates a mental image of the object’s shape, location, and movement. The brain uses visual cues such as shading, texture, and perspective to create a sense of depth and three-dimensionality.

In the case of the hyperboloid illusion, the lines of the hyperboloid shape create a series of perspective cues that trick the brain into perceiving the shape as three-dimensional. The way the lines converge and diverge creates an impression of depth and curvature, which makes the brain interpret the image as a curved surface.

The static ball at the center of the hyperboloid illusion appears to move because our brain assumes that it is following the contours of the curved surface, even though the ball is actually stationary. As we move our gaze around the image, our brain perceives the ball as moving in a smooth and continuous motion along the hyperboloid shape.

In summary, the Hyperboloid Optical Illusion works by using perspective cues to create the impression of a three-dimensional object, which tricks the brain into perceiving motion where there is none.

Some Similar Illusions

There are several optical illusions that are similar to the Hyperboloid Optical Illusion in that they use geometric shapes and perspective to create the impression of depth, motion, or three-dimensionality. Here are a few examples:

  1. The Ames Room Illusion – This illusion uses a distorted room with slanted walls to create the impression of a person growing or shrinking in size as they move across the room.
  2. The Penrose Stairs Illusion – This illusion uses a series of stairs that seem to loop back on themselves, creating the impression of an impossible three-dimensional structure.
  3. The Necker Cube Illusion – This illusion uses a simple cube shape that can be interpreted as facing in two different directions, creating the impression of an ambiguous or shifting shape.
  4. The Ponzo Illusion – This illusion uses a set of converging lines to create the impression of depth and distance, making objects at the top of the image seem larger than objects at the bottom.
  5. The Muller-Lyer Illusion – This illusion uses a set of arrows or fins that point in different directions to create the impression of depth or length, even though the lines are actually the same length.

These are just a few examples of the many optical illusions that use visual tricks to create the impression of three-dimensionality, motion, or other effects.

Discovery of the Hyperboloid Optical Illusion

It’s not clear who first discovered the Hyperboloid Optical Illusion, as the concept of using perspective and geometric shapes to create illusions has been used in art and design for centuries. However, the specific version of the Hyperboloid Optical Illusion that makes a static ball appear to move around a hyperboloid shape is a more recent development.

Since then, the Hyperboloid Optical Illusion has become a popular subject for artists, designers, and visual effects experts, and has been used in a variety of applications, including advertising, entertainment, and interactive media.


References and Resources

In addition to the Hyperboloid Optical Illusion, check out our complete list of illusions.

Moving In and Out Illusion

Moving In and Out Illusion

This Moving In and Out Illusion has a couple cool effects. Overall, the design appear to move due to some illusory motion dynamics, but it’s also impossible to tell if the centermost point is pointing in or pointing out.

There are at least two effects at play here: illusory motion and the crater illusion.

If you are interested in learning more about how the Moving In and Out Illusion works, scroll down to read more about it.

Moving In and Out Illusion


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What is the Moving In and Out Illusion?

The Moving In and Out Illusion has elements of both illusory motion and the crater illusion.

Illusory motion refers to the perception of motion in a static image or pattern that is not actually moving. This type of illusion can occur in a variety of ways, from the movement of static lines to the apparent rotation of an object.

One common example of illusory motion is the “motion aftereffect” or “motion illusion”. This occurs when you stare at a moving object for an extended period of time and then look away at a stationary object. The stationary object may appear to be moving in the opposite direction of the original moving object, creating the illusion of motion.

Another example of illusory motion is the “phi phenomenon”, which occurs when two or more static images are presented in quick succession. The images may appear to be moving or changing, even though they are actually static. This effect is often used in animation and film to create the impression of motion or change.

Illusory motion can also occur when viewing complex patterns, such as those found in Op Art or Kinetic Art. These patterns may appear to move or shift in different ways, even though they are static. This type of illusion is often referred to as “optical illusion motion”.

Overall, illusory motion is a fascinating example of how our brains interpret visual information and can be easily fooled by static images or patterns. It demonstrates the complex nature of perception and the many ways in which our brains construct a sense of motion and movement in the world around us.

The crater illusion is a visual illusion that creates the perception of a concave surface or a depression, even though the surface is actually flat. The illusion is created by a pattern of light and dark concentric circles or rings that are arranged in a specific way.

When the pattern is viewed from a certain distance, the concentric rings create a gradient of shading that gives the appearance of a three-dimensional depression, as if the surface is curved downward. This illusion is similar to the “Pinna-Brelstaff illusion”, which creates the perception of motion or rotation through the use of concentric rings.

How does the Moving In and Out Illusion Work?

The Moving In and Out Illusion has elements of both illusory motion and the crater illusion.

Illusory motion works by taking advantage of the way our brains process visual information.

When we see a moving object, our brains perceive it as moving based on the changes in its position over time. These changes are detected by cells in the visual cortex that are sensitive to motion, and they send signals to other parts of the brain that allow us to perceive the motion.

However, illusory motion can occur even when there is no actual movement because our brains can be tricked into perceiving motion based on other visual cues. One way this can happen is through the persistence of vision, which is the phenomenon where an image continues to be perceived by the brain for a brief period of time after it has been removed from view.

For example, in the case of the motion aftereffect, staring at a moving object for an extended period of time can cause the cells in the visual cortex to become fatigued, leading to a decrease in their sensitivity to motion. When you look away at a stationary object, the cells that are still responsive to motion may send signals to the brain that create the illusion of motion in the opposite direction of the original moving object.

Similarly, the phi phenomenon works by presenting static images in quick succession, causing the persistence of vision to create the impression of motion or change.

In the case of complex patterns, such as those found in Op Art or Kinetic Art, the illusion of motion may be created by the interaction of different visual cues, such as color, shape, and contrast. These cues can create the impression of motion or shifting patterns, even though the image itself is static.

Overall, illusory motion is a fascinating example of how our brains interpret visual information and can be easily fooled by a variety of visual cues. It demonstrates the complex nature of perception and the many ways in which our brains construct a sense of motion and movement in the world around us.

The crater illusion works by taking advantage of the way our brains interpret visual cues to create the perception of depth and three-dimensionality.

The illusion is created by a series of concentric circles or rings that are arranged in a specific way. The rings are shaded with alternating light and dark regions, with the dark regions increasing in width towards the center of the circle.

When the pattern is viewed from a certain distance, the shading of the concentric circles creates the impression of a gradual slope or depression. This is because our brains interpret the shading as a series of shadows and highlights caused by a light source positioned above the surface. Our brains assume that the light is coming from above, so the dark regions of the concentric rings are interpreted as the deeper parts of a concave surface.

The illusion is strengthened by the fact that the concentric circles themselves are reminiscent of round objects like craters or bowls, which further reinforces the impression of depth and curvature.

Overall, the crater illusion is a striking example of how our brains can be tricked into perceiving three-dimensional space even when the stimulus is actually flat and two-dimensional. It demonstrates the complex interplay between visual cues and interpretation that underlies our perception of the world around us.

Some Similar Illusions

Some illusions similar to the Moving In and Out Illusion include the following:

  1. Rotating snakes illusion: This illusion consists of a pattern of overlapping circles and curves that create the perception of continuous motion, as if the image is rotating in a circular motion.
  2. Motion aftereffect illusion: This illusion occurs when a person views a moving stimulus for a prolonged period of time, and then looks at a stationary object. The stationary object will appear to be moving in the opposite direction of the original stimulus.
  3. Autokinetic effect: This illusion occurs when a stationary point of light is viewed in a dark room for a prolonged period of time. The light will appear to move or “drift” even though it is stationary.
  4. Peripheral drift illusion: This illusion consists of a pattern of intersecting circles and lines that create the perception of motion at the periphery of the visual field.
  5. Barber pole illusion: This illusion consists of a rotating spiral pattern of alternating red and white stripes, which create the perception of upward motion even though the pattern itself is rotating.
  6. Wagon wheel illusion: This illusion occurs when a wheel appears to be rotating in the opposite direction of its true motion, due to the interaction between the frequency of the spokes and the frame rate of the video camera..
  7. The Ebbinghaus illusion (also known as Titchener circles) is a perceptual illusion in which the perceived size of a central circle is affected by the size of the surrounding circles. The central circle appears smaller when surrounded by larger circles, and larger when surrounded by smaller circles.
  8. The Delboeuf illusion is similar to the Ebbinghaus illusion, but instead of circles, it uses two concentric circles or rings. The central ring appears larger or smaller depending on the size of the surrounding ring.


References and Resources

In addition to the Moving In and Out Illusion, check out our complete list of illusions.

Also check out this cool example of the crater illusion.

Flying Bird Moiré Pattern Illusion

Bird Moiré Pattern Illusion

This Flying Bird Moiré Pattern Illusion creates the appearance of motion as a simple pattern is moved across the top of another.

A Moiré pattern illusion is a visual phenomenon that occurs when two or more semi-transparent or repetitive patterns are overlaid or placed in close proximity to one another, creating a new pattern with a different appearance. The resulting pattern often appears to move, shimmer, or vibrate, even though the underlying patterns are static.

If you are interested in learning more about how this Flying Bird Moiré Pattern Illusion works, scroll down to read more about it.

Bird Moiré Pattern Illusion
Artist: Kathleen Darby


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What is the Flying Bird Moiré Pattern Illusion?

The Flying Bird Moiré Pattern Illusion is created using a Moiré pattern which is a visual phenomenon that occurs when two or more semi-transparent or repetitive patterns are overlaid or placed in close proximity to one another, creating a new pattern with a different appearance. The resulting pattern often appears to move, shimmer, or vibrate, even though the underlying patterns are static.

Moiré patterns can occur in a variety of contexts, from digital images to physical objects. For example, when two screens with slightly different grid patterns are overlaid, a Moiré pattern may appear. Similarly, if a photograph of a fine mesh or grid pattern is printed on paper with another fine mesh or grid pattern, a Moiré pattern may also appear.

Moiré patterns can be used intentionally in design and art to create interesting visual effects, but they can also be a nuisance or a distraction, particularly in digital images or in printed materials that use fine patterns.

How does the Flying Bird Moiré Pattern Illusion?

The Flying Bird Moiré Pattern Illusion works using a Moiré patterns which is created by the interference of two or more repetitive patterns that are not perfectly aligned. When the patterns are overlaid or placed close together, the peaks and valleys of the patterns can either amplify or cancel each other out, resulting in a new pattern with a different frequency and appearance.

This interference can be understood through the concept of spatial frequency. The spatial frequency of a pattern refers to the number of cycles (repetitions) per unit of distance. When two patterns with different spatial frequencies are overlaid or placed close together, they can interfere with each other to create a Moiré pattern with a different spatial frequency.

For example, consider two grid patterns with slightly different spacings. When these grids are overlaid, some of the lines will line up perfectly, while others will be slightly offset. This creates a new pattern with a different spatial frequency that appears to move or vibrate when the grids are moved or viewed from different angles.

Moiré patterns can also be created by the interference of non-repetitive patterns, such as curved lines or irregular shapes. In this case, the interference is based on the differences in shape and orientation of the patterns rather than their spatial frequency.

Some Similar Illusions

There are several visual illusions that are similar to Moiré patterns and the Flying Bird Moiré Pattern Illusion in that they involve the interference of two or more patterns. Some of these illusions include:

  1. Op Art: Op Art (short for optical art) is a style of art that creates visual illusions through the use of repetitive patterns, such as lines or shapes. Like Moiré patterns, Op Art can create the illusion of movement or depth.
  2. Kinetic Art: Kinetic art is a form of art that involves movement or the illusion of movement. Some kinetic art pieces use repetitive patterns to create the illusion of motion or changing shapes.
  3. Anamorphic Art: Anamorphic art is a type of art that appears distorted when viewed from certain angles but resolves into a recognizable image when viewed from a specific viewpoint. Anamorphic art often uses repetitive patterns or grids to create the illusion of distortion.

Overall, these visual illusions demonstrate the power of perception and the ways in which our brains interpret and process visual information.

Discovery of the Flying Bird Moiré Pattern Illusion

Moiré patterns were first observed and described by French scientist, mathematician, and astronomer, Siméon Denis Poisson, in 1824. Poisson was studying the diffraction of light through a regular grid or mesh when he noticed the appearance of an unexpected pattern caused by the interference of the grid lines. He called this pattern “interference figures” or “Poisson’s figures”.

The term “Moiré” was later coined to describe similar patterns that were created when two different patterns were overlaid or placed in close proximity to one another. The term “Moiré” comes from the French word for “watered silk”, which has a similar rippling appearance.

Since Poisson’s discovery, Moiré patterns have been studied and applied in various fields, including physics, optics, engineering, art, and design. Today, they continue to fascinate researchers and artists alike as a fascinating example of the complex interaction between light, pattern, and perception.


References and Resources

In addition to the Flying Bird Moiré Pattern Illusion, check out our complete list of illusions.

Sinking House Illusion

Sinking House Illusion

This Sinking House Illusion can be found in Montmartre, a district in Paris, near the famous Sacre Coeur church. It’s a simple, but very cool illusion caused by forced perspective.

If you are interested in learning how forced perspective works in illusions like the Sinking House illusion, scroll down to read more about it.

Sinking House Illusion


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What is the Sinking House Illusion?

This Sinking House Illusion can be found in Montmartre, a district in Paris, near the famous Sacre Coeur church. It’s a simple, but very cool illusion caused by forced perspective.

The illusion works by taking advantage of the surrounding environment and forced perspective. The sinking house illusion is a great example of how forced perspective can be used to create illusions and challenge our perceptions of the world around us.

The Sinking House illusion has become quite popular among tourists and has been featured in various media outlets and publications. It is located in the Montmartre district of Paris, which is known for its vibrant arts scene and historical landmarks.

Forced perspective is a technique used in art, architecture, and photography to create the illusion of depth and distance in a two-dimensional space. The technique involves manipulating the visual perception of size and distance by adjusting the scale and positioning of objects in relation to the viewer’s perspective.

In forced perspective, objects closer to the viewer appear larger, while objects farther away appear smaller. This creates the illusion of depth and distance, even in a flat or shallow space. This technique is often used in films to make actors appear larger or smaller than they actually are.

Forced perspective has been used throughout history in various forms of art and architecture, from the ancient Greeks and Romans to the Renaissance painters and modern-day filmmakers. It continues to be a popular technique today, especially in the fields of architecture, photography, and special effects in movies.

How does the Sinking House Illusion Work?

The sinking house illusion uses forced perspective which works by manipulating the visual perception of size and distance. It takes advantage of the fact that the human brain perceives size and distance based on context and visual cues.

In forced perspective, objects closer to the viewer appear larger, while objects farther away appear smaller. By carefully adjusting the scale and positioning of objects in relation to the viewer’s perspective, an artist or photographer can create the illusion of depth and distance, even in a flat or shallow space.

For example, if an artist wants to create the illusion of a long hallway in a painting, they might draw the lines of the hallway so that they converge at a single point in the distance. This creates the impression that the hallway is receding into the distance, even though it is just a flat surface.

Similarly, in a photograph, a photographer might position a small object close to the camera and a large object farther away, making the small object appear much larger than it actually is in comparison to the larger object. This creates the illusion that the small object is closer to the viewer than it really is.

Forced perspective works best when the viewer is in a fixed position, such as looking at a painting or photograph, or standing in a specific location in an environment designed with forced perspective, like a tilted room or a miniature set. When the viewer moves around, the illusion may break down, as the visual cues and context change.

Some Similar Illusions

There are several similar illusions to the sinking house illusion, which also rely on manipulating visual perception to create an illusion of depth or distance. Here are some examples:

  1. Ames room illusion: This illusion involves constructing a room with an irregular shape, which appears to be a normal rectangular room from a specific viewpoint. When viewed from other angles, the illusion breaks down, making objects and people appear to change in size and shape.
  2. Anamorphic illusions: Anamorphic illusions involve distorting an image or object so that it appears normal when viewed from a specific angle, but distorted when viewed from other angles. Examples include street art that appears as a jumbled mess until viewed from a specific angle, or objects that appear to be elongated or flattened when viewed from certain angles.
  3. Trompe l’oeil: Trompe l’oeil is a type of art that uses realistic painting techniques to create an illusion of depth and three-dimensionality. This can include paintings that appear to be three-dimensional objects, or murals that make it seem like there is a real window or doorway where none actually exists.

Like the sinking house illusion, these illusions play with the viewer’s perception of size, distance, and depth, and rely on visual cues and context to create their effects.


References and Resources

In addition to the Sinking House Illusion, check out our complete list of illusions.

Purple and Green Illusory Motion

Purple and Green Illusory Motion

I just love this Cool Purple and Green Illusory Motion image. This is a completely static image. The combination of the unique shapes and shading create the illusion of motion.

If you are interested in learning more about how this Purple and Green Illusory Motion image, scroll down to read more about it.

Also check out these cool examples of illusory motion: Amazing Colorful Illusory Motion and Black and White Illusory Motion and Fun Circles Illusory Motion and Illusory Motion and Super Cool Illusory Motion

Purple and Green Illusory Motion


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What is Illusory Motion in the Purple and Green Illusory Motion Image?

Illusory motion is a type of optical illusion in which stationary images or patterns appear to be moving. This can occur in a variety of ways, such as through the use of patterns with alternating colors or shapes that create the illusion of motion, or by presenting a series of static images in rapid succession to create the perception of motion.

One well-known example of an illusory motion effect is the “rotating snakes” illusion, in which a series of static black-and-white shapes appear to be rotating in a continuous, fluid motion. This illusion is created by using patterns with specific shapes and contrasts that stimulate the brain’s motion-sensitive neurons and create the perception of movement, even though the image itself is not actually moving.

Other examples of illusory motion include the “scintillating grid” illusion, in which the intersections of a grid pattern appear to be flashing or moving, and the “phi phenomenon,” in which a series of static lights flashing in sequence create the illusion of motion.

Illusory motion can be a fascinating and captivating experience, and it has been the subject of much research in the fields of visual perception and neuroscience. Scientists continue to study the underlying mechanisms of illusory motion and other visual illusions in order to better understand how the brain processes visual information and creates our subjective experience of the world around us.

How does Illusory Motion Work?

Illusory motion is caused by the brain’s interpretation of visual information that is presented in a particular way. Different illusory motion effects may be created by different types of visual stimuli, but they all involve the brain perceiving motion where there is none.

One explanation for illusory motion is that it is caused by the brain’s motion-sensitive neurons responding to certain visual patterns or stimuli in a way that creates the perception of motion. These neurons, located in an area of the brain called the visual cortex, are responsible for processing information about motion and spatial relationships in the visual field. When presented with certain visual patterns or stimuli, these neurons can become activated in a way that creates the illusion of motion.

Another explanation is that illusory motion is a result of the brain’s tendency to fill in missing information in order to create a complete and coherent visual scene. When presented with incomplete or ambiguous visual information, the brain may “fill in the gaps” in a way that creates the perception of motion or movement.

In either case, illusory motion is a result of the brain’s complex processing of visual information, and it is influenced by a variety of factors, including the properties of the visual stimuli, the context in which they are presented, and individual differences in perception and interpretation.

Some Similar Illusions to the Purple and Green Illusory Motion

There are many different illusory motion illusions, each created by specific patterns or stimuli that trick the brain into perceiving motion where there is none. Here are some examples of illusory motion illusions:

  1. Rotating snakes illusion: This illusion consists of a pattern of overlapping circles and curves that create the perception of continuous motion, as if the image is rotating in a circular motion.
  2. Motion aftereffect illusion: This illusion occurs when a person views a moving stimulus for a prolonged period of time, and then looks at a stationary object. The stationary object will appear to be moving in the opposite direction of the original stimulus.
  3. Autokinetic effect: This illusion occurs when a stationary point of light is viewed in a dark room for a prolonged period of time. The light will appear to move or “drift” even though it is stationary.
  4. Peripheral drift illusion: This illusion consists of a pattern of intersecting circles and lines that create the perception of motion at the periphery of the visual field.
  5. Barber pole illusion: This illusion consists of a rotating spiral pattern of alternating red and white stripes, which create the perception of upward motion even though the pattern itself is rotating.
  6. Wagon wheel illusion: This illusion occurs when a wheel appears to be rotating in the opposite direction of its true motion, due to the interaction between the frequency of the spokes and the frame rate of the video camera.

These are just a few examples of the many illusory motion effects that have been discovered and studied by researchers in the field of visual perception. Each of these illusions demonstrates the brain’s remarkable ability to create the perception of motion and movement, even in the absence of actual movement.

Discovery of the Illusory Motion

Illusory motion has been known and studied by scientists and artists for centuries, but it is difficult to attribute its discovery or popularization to any single individual or group. The use of visual patterns and stimuli to create the illusion of motion has been explored in various forms of art, such as Op Art and Kinetic Art, and in scientific research on visual perception and neuroscience.

One of the earliest recorded examples of an illusory motion effect is the Zoetrope, a pre-cinematic device invented in the early 19th century that uses a sequence of static images to create the illusion of motion. Other early examples of illusory motion effects can be found in ancient Greek and Roman art, such as the use of mosaic patterns to create the impression of motion and depth.

In more recent times, scientists and artists have continued to explore and experiment with the use of visual illusions to create the perception of motion. Artists such as Bridget Riley and Victor Vasarely are known for their use of geometric patterns and shapes to create illusory motion effects, while scientists have used illusory motion as a tool for studying the brain’s processing of visual information.

Overall, illusory motion is a phenomenon that has been studied and appreciated by many different people throughout history, and it continues to inspire new forms of artistic and scientific exploration.


References and Resources Illusory Motion

In addition to this supercool Illusory Motion example, check out our complete list of illusions.

Cool Red and Black Scintillating Grid Illusion

Red and Black scintillating grid illusion

This Cool Red and Black Scintillating Grid Illusion creates the illusion of light and dark dots appearing at the intersections of a grid of white lines on a gray background. The dots appear to flicker and change color depending where you focus your view.

If you are interested in learning more about the Scintillating Grid Illusion, scroll down to read more about it.

Red and Black scintillating grid illusion
White and Black scintillating grid illusion


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What is the Red and Black Scintillating Grid Illusion?

The scintillating grid illusion is an optical illusion that creates the illusion of light and dark dots appearing at the intersections of a grid of white lines on a gray background. The illusion is caused by the way the brain processes visual information.

When viewing the scintillating grid illusion, the brain tries to process the contrast between the dark dots and the light background. However, the brain also perceives the white lines as being brighter than the gray background, which creates a brighter area around the intersection of the lines. This makes the dark dots appear even darker and creates the illusion of light and dark dots appearing and disappearing at the intersections.

The scintillating grid illusion is an example of the Hermann grid illusion, which was discovered by the German physiologist Ludimar Hermann in 1870. The Hermann grid illusion works in a similar way, but instead of white lines, it uses black squares on a white background to create the illusion of gray dots at the intersections.

How does the Red and Black Scintillating Grid Illusion Work?

The Scintillating Grid Illusion is an optical illusion in which a grid of light gray or white lines on a dark background appears to flicker or “scintillate.” The effect is most pronounced when the observer is looking directly at the intersection of the lines, and it is caused by the way the visual system processes the edges of the lines. The illusion is often used to demonstrate the neural processes that underlie visual perception, and it is related to other optical illusions such as the Hermann grid illusion and the Mach bands illusion.

The Scintillating Grid Illusion is believed to work by the way the brain processes the edges of the lines in the grid. The visual system is sensitive to the contrast between light and dark areas, and the edges of the lines in the grid create a high contrast between the light lines and the dark background. This high contrast causes the visual system to enhance the edges, creating the illusion of flickering or scintillating.

It’s also thought that the mechanism behind this illusion is related to the way the visual system deals with the ambiguous edges of the lines. In the intersection of the lines, the brain receives information that is not clear, and it tries to fill in the missing information by creating the illusion of movement.

Additionally, the illusion is more pronounced when the observer is looking directly at the intersection of the lines, as opposed to looking at the lines themselves. This is likely due to the fact that the visual system is more sensitive to edges that are oriented perpendicular to the line of sight.

Some Similar Illusions

The Hermann Grid Illusion: This illusion is created by the way the brain perceives intersections of lines. When the intersections of a grid of lines are viewed, small gray dots appear at the intersections, even though they are not actually there.

Hermann Grid

The Bezold Effect: This illusion is created by placing two or more colors next to each other, and the way they appear to change when they are close to one another.  

Bezold_Effect

The Café Wall Illusion is a visual illusion that is created by a grid of alternating light and dark horizontal and vertical lines. The lines appear to be bent or tilted, even though they are actually straight.

Cafe Wall Illusion

Discovery of the Red and Black Scintillating Grid Illusion

The Scintillating Grid Illusion is a variant of the Hermann Grid Illusion named after Ludimar Hermann, a German physiologist, who first described it in 1870

Ludimar Hermann (1838-1914) was a German physiologist and psychologist who was best known for his work on the perception of visual images and the nature of visual illusion. He is most famous for his discovery of the Hermann grid illusion, which he described in 1870. It is a visual effect that occurs when viewing a pattern of light and dark lines crossing each other to form a grid, creating the appearance of gray spots at the intersections of the lines, even though the intersections are actually the same color as the background.

He studied medicine in Berlin, later he was a professor of physiology and neurology in Würzburg and Tübingen. He also worked on other aspects of visual perception, such as the perception of movement and the illusion of movement, as well as on the perception of sound and hearing. His ideas had a significant influence on the development of psychology and neuroscience. He was also an important figure in the history of neurology and psychiatry.


References and Resources

Check out our complete list of illusions.

Optical Art Illusions

Optical Art Illusion

Op Art, short for Optical Art, is a style of art that emerged in the 1960s and is characterized by the use of optical illusions, geometric shapes, and bright colors to create the impression of movement, depth, and visual vibration.

If you are interested in learning more about Optical Art Illusions and seeing some more examples, scroll down to read more about it.

Optical Art Illusion
Victor Vasarely “Zebra”


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What are Optical Art Illusions?

Optical Art, short for Optical Art, is a style of art that emerged in the 1960s and is characterized by the use of optical illusions, geometric shapes, and bright colors to create the impression of movement, depth, and visual vibration.

Optical Art often employs simple geometric shapes such as squares, circles, and lines, arranged in patterns or sequences that create a sense of movement or distortion. The art form relies on the viewer’s perception and the way that the human brain processes visual information, often resulting in images that appear to be pulsing, vibrating, or even moving.

Optical Art is heavily influenced by the scientific and technological developments of the time, such as advances in color television, photography, and printing techniques, which allowed artists to experiment with new forms of optical illusions and visual effects.

The style was popularized by artists such as Bridget Riley, Victor Vasarely, and Yaacov Agam, among others, and has had a significant influence on contemporary art, design, and popular culture. Today, Op Art continues to be a popular style among artists who are interested in exploring the intersection of art and perception.

How do Optical Art Illusions Work?

Optical Art works by exploiting the way the human brain processes visual information. The style relies on optical illusions, such as the Moiré effect, in which the viewer perceives patterns or lines that are not actually present, or the illusion of movement, in which a static image appears to be in motion.

Optical Art often employs simple geometric shapes such as squares, circles, or lines, arranged in patterns or sequences that create a sense of movement or distortion. These patterns and sequences are designed to activate the viewer’s visual cortex, which is responsible for processing visual information and making sense of what we see.

When we view an Optical Art piece, our brain tries to interpret the patterns and shapes it is seeing, leading to various perceptual effects such as the impression of movement, depth, and visual vibration. These effects are created by the contrast between the different colors or shades used in the artwork, as well as the way the shapes and patterns are arranged.

Op Art works because our visual system is constantly trying to make sense of the information it receives, and the style exploits the way our brains process visual information to create images that are visually engaging and dynamic.

Some Examples of Optical Art Illusions

Optical Art is a style of art that emerged in the 1960s, characterized by the use of geometric shapes, bright colors, and optical illusions to create the impression of movement and depth. Here are some examples of Op Art:

Bridget Riley’s “Movement in Squares”: This painting, created in 1961, features a series of black and white squares arranged in a grid that creates the impression of movement and depth.

Optical Art Illusion
Bridget Riley’s “Movement in Squares”

Victor Vasarely’s “Zebra”: This painting, created in 1937, features a series of black and white stripes arranged in a way that creates a sense of vibration and optical illusion.

Optical Art Illusion
Victor Vasarely “Zebra”

Jesus Rafael Soto’s “Penetrable”: This sculpture, created in 1967, features a series of hanging wires that create an immersive, three-dimensional environment in which viewers can move and interact.

Jesus Rafael Soto’s “Penetrable”

Yaacov Agam’s “Double Metamorphosis II”: This sculpture, created in 1964, features a series of rotating panels that create a sense of movement and change depending on the viewer’s perspective.

Optical Art
Yaacov Agam’s “Double Metamorphosis III”:

These are just a few examples of Op Art, which continues to be a popular style among artists and designers who are interested in exploring the intersection of art and perception.

Discovery of Optical Art Illusions

The Optical Art movement emerged in the mid-1960s, and it is difficult to attribute its creation to a single artist or individual. The style was influenced by a variety of artistic and scientific movements of the time, including Abstract Expressionism, Kinetic Art, and the study of color and perception.

Some of the earliest and most influential Op Art artists include Victor Vasarely, Bridget Riley, and Jesús Rafael Soto. Vasarely, who is often credited with coining the term “Op Art,” began creating geometric abstract art in the 1930s and is considered one of the pioneers of the style. Riley, who emerged in the 1960s, is known for her black-and-white paintings that create optical illusions of movement and depth. Soto, who was also active in the 1960s, created sculptures and installations that engage the viewer in an immersive, three-dimensional environment.

Overall, Optical Art was a movement that emerged out of a broader cultural and artistic context, and many artists contributed to its development and popularity in the 1960s and beyond.


References and Resources

Check out our complete list of illusions.