Persistence of vision is the phenomenon by which the brain continues to perceive an image even after the image is no longer present.
This occurs because the cells in the retina, called rods and cones, take a brief period of time to “reset” after being stimulated.
As a result, when an image is removed, these cells continue to send signals to the brain for a short period of time, creating the illusion that the image is still present.
Persistence of vision is the scientific explanation behind the afterimage illusion, as well as the illusion of motion in moving pictures such as films and animations.
Table of Contents
- How does the Persistence of Vision work?
- Versions of the Persistence of Vision
- Illusions like the Persistence of Vision
- Discovery of the Persistence of Vision
- References and Resources
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How does the Persistence of Vision work?
Persistence of vision works by the way our eyes and brain process visual information. When light enters our eyes, it is absorbed by cells in the retina called rods and cones. These cells then send electrical signals to the brain, which interprets these signals as visual information. The brain is able to process images very quickly, and can hold onto an image for a brief period of time even after it is no longer present. This is known as the “persistence of vision.”
When we watch a movie or animation, for example, the images are presented to us in rapid succession. The brain combines these images and interprets them as a single, continuous image, creating the illusion of motion. This is due to persistence of vision.
Similarly, when we see a light being turned on and off quickly, the brain combines these images and interprets them as a single, continuous light. This is also due to persistence of vision.
Persistence of vision also plays a role in other visual phenomena, such as afterimages, optical illusions and other types of illusions, as well as in some cases of visual hallucinations.
It’s worth noting that persistence of vision is not a unique property of human vision, many animals have this ability as well.
Versions of the Persistence of Vision
There are many examples of persistence of vision in everyday life. Some of these include:
Moving pictures: When we watch films or animations, the rapid succession of still images creates the illusion of motion. This is due to persistence of vision.
Flickering lights: When we see a light being turned on and off quickly, it can create the illusion of a continuous glow. This is also due to persistence of vision.
Spin art: When a spinning object is decorated with different colors, the colors appear to blend together and create new colors. This is due to persistence of vision.
Fireworks: The bright trails left by fireworks are caused by persistence of vision, as the brain continues to see the light even after the firework has exploded.
Afterimages: When we look at a bright light, or an image for an extended period of time, and then look away, we can see an afterimage of that image or light. This is also caused by persistence of vision.
The following are some other examples of Persistence of Vision
Illusions like Persistence of Vision
Some related illusions include the following:
Afterimage Illusion
The afterimage illusion is a type of visual illusion in which an image continues to appear in the observer’s visual field after the original stimulus has been removed.
The Checker Shadow Illusion is created by a checkerboard pattern composed of squares with different luminance values, the squares that are not directly illuminated by the light source appear darker than the illuminated squares, creating the illusion of shadows.
The simultaneous contrast illusion is a visual effect that occurs when the perception of a color is affected by the colors of the surrounding area.
The illusion creates the appearance of a change in the color of an object, even though the actual color of the object remains constant.
The Neon Color Spreading illusion refers to the visual phenomenon where an area of color appears to spread or “bleed” beyond its intended boundaries.
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.
The Cornsweet illusion is a classic example of a brightness illusion, which is an illusion in which two areas that are physically the same brightness appear to be different in brightness.
The Chubb illusion is based on the perception of brightness and can be observed when a small bright patch is surrounded by a larger dark area, the small bright patch will appear brighter than the same patch surrounded by a bright area.
The Watercolor Illusion: This illusion is created by the way the brain perceives edges of an object. When an object is surrounded by a colored halo, the object appears to have a different color than it actually does.
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.
Discovery of the Persistence of Vision
The phenomenon of persistence of vision, has been known for centuries.
The ancient Greeks and Romans were aware of the phenomenon, and it was also described by the ancient Chinese and Arab scholars.
The earliest scientific study of afterimages was done by the German scientist Hermann von Helmholtz in the 19th century.
He published a book in 1867 titled “Handbook of Physiological Optics” which gave a detailed explanation of the phenomenon, including the theory that afterimages were caused by the retina’s sensitivity to light.
This study is considered as one of the earliest and most comprehensive explanations of the effect.
References and Resources
Check out our complete list of illusions.