You always see yourself in a mirror. Have you ever wondered what the color of a mirror is? It’s a tricky but interesting question. The mirror reflects light at the same angle and direction from which it arrives. It is called specular reflection, which creates an image of whatever is in front of it.
The “specular” means “mirror” in Latin. With this type of reflection, different images depending on how you look at the mirror. The image changes as we move around a room. It gives the illusion through a window into some mirror universe.
What is the color of mirror?
The word reflection comes from the Latin “reflectere,” meaning “to bend backward,.” They bend the light backward but in very different ways. They’re going to end the same, aren’t they? Even under a microscope, a mirror is incredibly smooth, so the surface always faces the same direction. The light still obeys the law of reflection at each spot, but different spots face different directions, so the light scatters instead.
Do you think it is white or silver? If you think so, you are wrong, and if you think it is colorless, you are absolutely wrong. So what’s the color? Before starting, here’s a question for you.
First of all, we need to know how anything reflects any color. It is the wavelength of all the reflected ways with its maximum intensity from the object and color. Let’s take the example of grass. The grass is green in color, but why? It’s because grass absorbs all the color except green color and reflects it.
White light contains seven colors. If seven color falls on grass then why do we see it as green only? When all seven colors force on grass, then grass absorbs all the colors except green. And that green is reflected from grass which appears green.
Do you know that black is not a color? When an object can absorb all the seven colors of white light, it appears black. Black is the absence of color. And when an object reflects all colors, it becomes transparent. Now back to the topic, if you take yellow paper and shine pink light on it, the paper will try to reflect as much yellow as it could. And it will try to absorb all pink colors. But it can absorb only up to a limit.
When you eat the food as much as possible and reject the remaining food, the same happens here. Paper will absorb all pink color and reject yellowback. As Pink light is more than yellow light, so it reflects pink more than yellow. This is also a reason laser light strength gets lighter after reflecting one wall to the other.
So the mirror reflects all the colors. So shouldn’t it be white? No, as mentioned earlier, it is not white. A mirror may look white or silver as it is usually depicted. The mirror reflects in a wavelength that is 510 NM which is green in color. You cannot see the wave with your eyes because it is 5.1 x 10 negative 7 meters, which is incredibly small. Don’t believe it? You can prove it yourself with the help of a mirror tunnel or an infinite mirror.
A mirrored tunnel is basically to mirror put facing each other. It creates an image inside an image, and so on. It is endless. Here a question will come to your mind why it is getting smaller. It is because of the distance between the two mirrors. Why does the image getting a little blurred? It is because the mirror not only reflects but also absorbs little light. It is like I give you an apple, and you eat little of it and pass it back to me.
Why mirror is green?
Now you will also see at last it appears green. But why green? It is because common mirrors have a layer of glass soda. It is normally soda-lime glass and has iron oxide impurities which give it a slightly greenish color. If you don’t feel able to see, don’t worry. Your mirror may be too polished.
The mirrored surface is made of atoms, usually silver or some other shiny metal. We like to imagine that light interacts with the atoms on top, but there are spaces between those atoms that the light can fit through. Scattering can happen off many layers of atoms and still contribute to the reflected light. The mirror-like reflection in this plastic is from the surface atoms. The color is from the layers underneath. And that’s not even considering the wave nature of light. If we do that, each atom sends out its light in all directions, including the material.
Ultimately, those light waves cancel except in two specific directions. The incoming beam splits in two at any surface. It doesn’t have to be transparent. Some of the light will reflect. How much is reflected or transmitted depends on many things: the materials involved, the incoming angle, the frequency of the light, etc.
- For an air-glass boundary, the light is about 5% reflected and 95% transmitted because of transparency. For a mirrored surface, it’s the other way around.
The point is there’s always some transmitted light, even for a mirror.
What makes these materials different is how far that transmitted light can go. It’s something call Penetration Depth. This penetration depth depends on four things:
- The electric and magnetic field properties of the material.
- The frequency of the incoming light.
- The electrical resistance the material can provide.
For a silver mirror, it’s 1.4 nanometers. That’s drastically different from glass. So it goes that far and stops? Well, no. The light intensity drops off exponentially. A penetration depth of 1.4 nanometers means that for every 1.4 nanometers, the light goes into the silver. At one penetration depth, the intensity is 37% of the original. At five penetration depths, the intensity drops below 1%.
For the silver mirror, that’s still only 7 nanometers. That transmitted light is going nowhere fast. Based on this equation, we can see transmitted light won’t go as far in electrical conductors. That’s what gives metals that distinctive metal coloring we all recognize. The light barely penetrates.
There are two different ways that atoms can absorb light: Resonant Absorption and Dissipative Absorption. Resonant absorption is when a single electron absorbs a single photon with just the right energy needed to bump the electron to a higher energy level. This is the kind of absorption that results in things like fluorescence and phosphorescence. It is not the kind of absorption that creates reflected and transmitted light beams. When this happens, the electron usually doesn’t have a chance to re-emit that light.
Fluorescence and phosphorescence are just special exceptions. Reflected and transmitted beams come from the other type of absorption: Dissipative Absorption. This type doesn’t require quantum mechanics. It is a very classical effect. An atom is just minding its own business when some light comes along. Because the atom is made of charge, the light’s electric field drives the atom’s motion. And they are also responsible for the green color of the mirror.
Frequently asked questions
What is a mirror made of?
About five thousand years ago, mirrors were made of highly polished metal discs such as bronze copper and super-rich gold. In all cases, a mirror was a highly prized symbol of status and wealth. But then, around the first century Common Era, another style of mirror arrived, the metal-backed glass mirror. By the 16th century, glass artisans in the Republic of Venice had become pretty good at silvering. That’s the process of coding glass with a thin layer of metal. The only thing one metal is used in this process was mercury, also known as one of the most toxic metals in the world.
Then in the mid-1800s, German chemist Justus von Liebig figured out how to use actual metallic silver in his silvering process. A mirror begins as a large sheet plate glass is first cleaned with hot demineralized water, and then the layering begins. First comes a layer of liquid tin and then silver, though some manufacturers will use aluminum here instead.
In either case, these metals react with one another or harden, and presto, you have a reflective surface. It’s a relatively simple matter of covering this sewing with a couple of layers of protective paint. It is then baked to cure or set that coating. Underneath the layer of glass, the silver ring will never need polishing and never dull.
What are the two types of mirrors?
There are two major types of mirrors. One is the curved mirror, and the other is a flat mirror.
Why do mirrors flip left?
You’ve probably noticed that words look backward in a mirror, but they aren’t upside down. Mirrors don’t flip left and right or up and down. If you look carefully at a scene in a mirror, you’ll notice that everything on the left stays on the left, everything on the right stays on the right. Also, everything up stays up, and everything down stays down.
What does get flipped is the direction into or out of the mirror? The things closest to us end up farthest away, and those farthest from us end up closest. Mirrors flip not left and right, nor up and down, but depth – they flip in and out. And mirrors invert in and out because they reflect light according to the principle of specular reflection: light coming into the mirror at a given angle bounces back off at the same angle.
Read More: Why Red Sea Is Called Red?
M. A. Kallistratova. “Physical grounds for acoustic remote sensing of the atmospheric boundary layer”. Acoustic Remote Sensing Applications.
Fioratti, Helen. “The Origins of Mirrors and their uses in the Ancient World”. L’Antiquaire & the Connoisseur.