From a pool of water filled with dark-colored dye to special mirrors, we have come a long way.The oldest man-made mirror can be traced to around 8,000 years ago in modern-day Turkey. Humans polished obsidian and used it as a reflective surface.In ancient times, mirrors were also in use in Egypt, Mesopotamia, and China by 2,000 BC. Metallic mirrors were made by using a highly-polished flat piece of bronze, copper, and other precious metals. Ancient mirrors were heavy and were available in small sizes only. Even in the 17th century, these mirrors were used for decoration purposes only. Did you know there is a massive salt flat in Bolivia that is crowned as the largest mirror on Earth? This salt flat becomes highly reflective when rainwater collects on its surface.Years later, contemporary mirrors were introduced but their manufacturing was both expensive and difficult. Apart from this, when heat was used to attach the metal to the glass, the hot temperature often broke the glass. Only during the Renaissance period, did Florentines invent a process through which low-temperature lead backing became possible and modern mirrors came into being. However, mirrors were still expensive and only the rich could afford them. During medieval times, mirrors remained more of a status symbol.A German chemist, Justus von Liebig, is credited with the invention of the modern silver-glassed mirror in 1835. He developed the process of attaching a thin metallic silver layer to one side of a glass. Soon, this technique was adopted and worked on. He is also accredited for the invention of convex and concave mirrors.In the 19th century, we also saw a rise in the popularity of beveled glass. However, it is believed they were sold for the first time in the 16th century. They became readily available for purchase during the Industrial Revolution. At present, glass and polished metal surfaces are used to make a framed mirror of any shape and size.What are mirrors made of?Mirrors are made of varied materials. Read on to learn the details.Modern mirrors are either made by spraying a thin layer of aluminium powder or silver on the back of the glass sheet or heating aluminum powder and then attaching it to the glass.Though aluminum is widely in use, other metals like silver, gold, and chrome can also be used for the metallic coating.Glass, considered a good mirror material, is made from silica and molded into various shapes and sizes. In a regular mirror, glass is made from natural silica crystals known as fused quartz. Other kinds of glass, such as synthetic glasses, are also available.For scientific purposes, high-quality glasses are used. Some chemical is used to make the glass resistant to pressure and other environmental extremes.At times, different materials are also used to coat these scientific mirrors like silicon nitrides and silicon oxides.In some instances, a plastic substrate can also be used to make mirrors. For example, in children’s toys, plastic polymers are molded to form the mirrors as they do not break easily like glass mirrors.Types Of MirrorsMirrors are not only used for getting reflection but also for adding depth to a room and increasing its beauty. Here are some of the common types of mirrors:The common variety of mirrors, plane mirrors have a flat surface that reflects images in the same proportions as of the object but remain laterally inverted. This means, if a person raises their left hand, your reflection in the mirror would have their right hand raised.Though flat, these mirrors can be curved into various designs to add grace to your house.They are also available in multiple shapes and sizes ranging from the tiny mirror in your makeup compacts to the shape of animals, toys, letters, and more. One example is the special flat glass you use as a mirror in your house.Several experiments are performed with plane mirrors. For example, sitting in front of a mirror in a darkened room and staring at your reflection for around 10 minutes can give you hallucinations. You may experience a strange illusion.A spherical mirror has a curved surface that appears to be cut out of any spherical shape. For example, concave and convex mirrors.Convex mirrors have a surface that is curved outward. You will get a diminished, virtual and erect mirror reflection of an object in this case. Convex mirrors are used as side mirrors on cars and as large mirrors in parking spaces.Concave mirrors are curved inwards just like a spoon. They give images that are larger than real objects. A perfect example will be your looking glass in the bathroom.Thanks to the versatility of spherical mirrors, they can be found in numerous sizes and shapes. They were invented by Justus von Liebig.Most of these mirrors are either made out of glass or any kind of polished metal surface.One/ two-way types of mirrors are partially reflective and transparent. In this kind of mirror, only one side is coated that reflects the light, which then travels into the darkness behind the mirror.The coated side contains materials like silver, tin, or nickel that are applied only to the glass’ backside. Thereafter, the glass is tucked inside a copper material to avert oxidation, and finally, it is painted.These mirrors find their use in hidden security cameras, experimental labs, interrogation rooms, and the like. They too are available in dozens of sizes.Silvered mirrors are coated with reflective material, mostly silver. However, before the 18th century, a blend of tin and mercury was in use to give the silver coating to the mirror. Later, pure silver was used.Now though, a mixture of sputtering aluminum among other compounds is in use, but the mirror is still called silver.These mirrors are highly reflective and stronger compared to their variants.Mostly large mirrors are silvered but you can use this process on any size and shape of mirror.Also called parabolic sound mirrors, acoustic mirrors, like a regular mirror, do not reflect images but reflect sound waves.They were high in use in the military once and are made of concrete instead of glass. These mirrors also find their use in science museums for demonstrations related to sound waves.These mirrors are usually used inside microphones or other devices to reflect sound. There is no standard size of parabolic mirrors and they are made of an object called a parabolic dish.Non-reversing mirrors, commonly called flip mirrors, refers to two mirrors juxtaposed at a 90-degree angle.The mirrors you find in dressing rooms and public washrooms are an example of this kind.When trying to make a non-reversing mirror, it is best to go for medium or large mirrors.You can customize mirrors into different patterns. One common example is mirrored backsplashes. Their addition makes your room look bigger and brighter.You can customize mirrors to make mirrored tabletops, mirrored walls, and use special frames like tiles and gold highlights.Characteristics Of MirrorsMirrors have several magnification properties. You can use curved mirrors to form a reflected angle and change the size of the image. Continue reading to find more about their characteristics.Images formed by plane mirrors are erect and laterally inverted. Also, the image is the exact size of the object.The distance of the object from the mirror is the same as the distance of the reflection from the mirror.The image is formed behind the mirror and not on the mirror.As a proper mirror reflects all colors, including white, it is also white. When a plane mirror reflects another mirror, the light beam gets bounced back from the mirrors’ surfaces repeatedly and forms a new image.Concave mirrors, also referred to as converging mirrors, are curved inwards. They collect light rays to a focal point before reflecting them.They form a magnified and virtual image. Upon increasing the distance between the concave mirror and the object, you get the real image but it is smaller in size.By changing the position of an object in front of the concave mirror, you obtain a variety of images. You can get different images by placing the object at the infinity, at the focus, or between focus and center of curvature.The convex mirror, also referred to as diverging mirrors, bulges outside and always forms an erect, virtual, and diminished image.Changing the distance between the object and a convex mirror has no effect on the mirror image.A one/two-way type of mirror allows reflection at one side and remains see-through on the other side. If a mirror is reflecting another mirror, it has a slight green shade.These mirrors are made the same way as traditional mirrors, the only difference being they are given half the quantity of metal backing when compared to traditional mirrors.Only a single coat of metal is given so that the maximum amount of light gets reflected to its source without allowing some of it to pass through. This makes the glass transparent for the people on the other side allowing them to have a clear view across it.However, the coating darkens the view from the non-reflective side, creating a feeling of looking via a tinted window.How do mirrors work?Almost all households have mirrors and we use them every day but have you wondered how these mirrors work or why only mirrors give a reflection and not any other object? Here’s the answer:Most mirrors are constructed using glass, a slim layer of metal backing, mostly aluminum, and multiple paint layers.Do you know the glass is not the most essential part of a mirror? Instead, it is the metal backing. The glass surface performs an important function of protecting the metal’s wafer-thin layer and smoothness.As a beam of light passes through the glass surface and reaches the metal part, the latter reflects it. The paint performs a similar protective function at the backside of the mirror by ensuring the metal stays in place.Why is a mirror so uniquely reflective? Well, when rays of light from an object, say a shirt, hits the smooth surface of the mirror, all the rays of light (photons) bounce back at the same angle and you get to see the reflected photons as the image.Now this image is reversed and you can easily find this out by using a shirt with words on it. You won’t be able to read the words as they will be reversed.A mirror reflects every color that strikes on it and this makes it unique. Most objects fail to reflect all the color as they end up absorbing some.For example, when a beam of light hits a red apple, the apple soaks in all the colors, except red, which gets reflected, making the apple appear red.However, not all white surfaces that appear flat and smooth, like white paper or walls, can reflect light like a mirror.The reason is that these surfaces aren’t smooth at the microscopic level. Even small distortions can fail to produce a clear reflection.If you zoom in on a paper or wall, you will find its surface bumpy. So, the light gets reflected in all directions. This phenomenon is called diffuse reflection.This same principle works when light strikes other smooth surfaces such as a calm pool of dark water.When you look at it on a windless day, the water will give your reflection by producing specular reflection but on a windy day, when there is a ripple in the water, it will provide you a distorted reflection by producing a diffuse reflection.
From a pool of water filled with dark-colored dye to special mirrors, we have come a long way.
