For those that don’t know “eye black” is the substance used to make the dark markings athletes place under their eyes that are supposed to prevent glare from outside light sources, such as stadium lights and the Sun. It’s also supposed to help with contrast recognition (being able to tell the color of objects that make them distinguishable from objects in the background)- like when a baseball player is trying to see a ball coming at 100 mph when there is a gray background, such as a pitcher’s uniform. Before we talk about exactly how eye black is thought to work, it’s important to understand what light is and the effect it has on our eyes.
Light is merely electromagnetic radiation. Electromagnetism is one of the four fundamental forces in the universe, the others being gravity (for now) and the nuclear weak and strong forces. This “light” radiation comes in many forms you probably recognize- from the long wavelength (low frequency radio waves, microwaves, and infrared waves), to the shorter wavelength (higher frequency ultraviolet waves, x-ray waves, and Gamma-ray waves). Right in the middle of these, is a sliver of the spectrum that we can see with our human eyes, namely visible light waves. The wavelengths we are able to see range from about 380 nanometers (your purples and blues) to about 740 nanometers (your reds).
Inside our eyes we have two types of cells that detect light (photoreceptors). They are known as rods and cones. There are many more rods in our eyes than cones (about 120 million rods compared to 6-7 million cones). The rods are more sensitive, but the cones allow us to see color. There are three types of color reception in our cones (thus, 3 primary colors).
How light is absorbed or reflected has to do with how the specific frequencies of light affects the electrons that are attached to the atoms within the molecules of the cells. Electrons travel around atoms at specific frequencies. When those frequencies match the frequencies of light waves hitting the object, that object will absorb the frequency of light. When it doesn’t match, that object will reflect those frequencies back. The rejected frequencies are what our eyes perceive as objects and color. Thus, if you see something that is green, that object is absorbing all the frequencies of light, except the ones associated with green. When an object appears white, it is reflecting nearly all light frequencies back at your eyes, and not absorbing any. When an object appears black, it is absorbing almost all light frequencies and reflecting none back.
When the objects we see, like a baseball, are perceived by our eyes, and there is another light source that is greater than the one illuminating the object (baseball), it produces a glare that is also picked up by our eyes. This glare also affects how the electron and light frequencies work to create an image. This scattering of light makes the object we are looking at appear less defined, playing havoc on anyone who makes a living at using their vision. If you’ve ever driven at night and had trouble seeing when there are oncoming headlights, you know what I’m talking about.
The glare associated with trying to perceive objects around you, when there are intense light sources like the Sun, or stadium lights, is known as “disability glare”. According the International Commission on Illumination (CIE), disability glare is defined as “A visual condition in which there is excessive contrast or an inappropriate distribution of light sources that disturbs the observer or limits the ability to distinguish details and objects”.
Basically, the rods and cones in our eyes begin to perceive light sources from different angles. These differing light sources begin to cause the rods and cones to be unable to distinguish specific shapes and objects, much like trying to hear someone talk over a loud radio.
The idea behind eye black is to reduce the amount of glare that reaches your eyes. Because black colors absorb most light frequencies, it is thought that the excessive light coming from sources we are not looking at will be absorbed by the black color. Placing the black just below our eyes will, in effect, reduce the glare, thereby increasing the definition and contrast of the objects we are looking at.
The theory is sound, but does it work? The short answer is, probably. There has been only one seemingly legitimate study that I could find that has tested this theory, done by Brian M. De Broff, MD and Patricia J. Pahk, MD in 2003; it was published in the Journal of American Medical Association. They tested the difference between eye black, commercially available black stickers, and petroleum jelly. What they found was that you did get an increase in your ability to perceive contrast differences in objects with both the eye black and the commercially available stickers. They also found that the eye black was better than the stickers. The ancillary evidence of the popularity of eye black, also speaks to its ability to work. Being someone who likes irrefutable scientific evidence before he makes any statement as to the accuracy of a theory, I must point out this study is the only one done, and it had a very small sample group (only 46 people).
So not quite as definitive as I normally like to be, but seems reasonable enough given that the theory behind eye black is a good one and the only scientifically done study on the subject proved positive. (For those who put stock in somewhat non-scientific studies, MythBusters also agreed with the study after doing their own experiments.) The small sample size and the lack of any major studies that have replicated the results makes me hesitant to say that it absolutely works, but I’ll update this article if that changes in future. If nothing else, eye black sure makes a person look scary and intimidating, which will also help on the field of battle!
If you liked this article and the Bonus Facts below, you might also like:
- Why We Divide Time Up Into Seconds, Minutes, and Hours
- The Origin of the Word “Soccer”
- Does Sex Before an Athletic Event Really Hinder Performance?
- What Causes Red Eyes in Photographs
- Reading in Dim Light Will Not Damage Your Vision
- Reducing the glare from the sun is nothing new. The first known anti-glare devices were used by Eskimos about 2000 years ago. They made goggles from ivory and wood that had horizontal slots in them. This allowed them peripheral vision while blocking light that was reflected by snow and ice.
- The first known commercially available means of blocking glare came from the Sears, Roebuck and Company. They began selling sunglasses in 1886.
- Eye black grease is made from mixing carbon, paraffin, and beeswax.
- According to the advertisements on commercially available anti-glare stickers, the appropriate way to place the stickers is ½ inch below the eyelid, on the cheekbone.
- The first person credited with using eye black was Andy Farkas of the Washington Redskins. He was photographed with it on in a game against the Philadelphia Eagles in1942. It was thought that players at that time burned cork and smeared the ashes on their cheeks.
[Image via Shutterstock]
Expand for References