Your kids will LOVE this project from our August Winkle Crate! They get to make and design their own optical illusion spinner and learn some science while they play (win, win. Right mom?)
The human eye is comprised of two types of receptors: rods and cones. Cones allow us to see color and work well in bright light. Rods are used to see in low light. When a color wheel or optical illusion, like the Benham Disk, spin the brain has to process the colors the eye perceives very quickly.
In a spinning color wheel, the images blend and we see colors we might not have expected. Scientists have several theories on why we see the colors we do when we spin an optical illusion like the Benham Disk or Maxwell Top. One theory is the different types of cones respond to the image at different rates and stay activated for different periods of time, thus we see colors when the disk spins. Another theory is the black and white spaces activate different parts of the retina of the eye causing interactions with the nervous system that allows us to see colors. Scientists are still unclear exactly why this phenomenon occurs, but one thing is clear- your kids will love it!
Try designing it with different colors and be surprised by what your eyes actually see.