The mirror is made of the earliest pieces of polished stone such as obsidian, a volcanic glass that is formed naturally. Obsidian mirrors found in Anatolia (now Turkey), lived around 6000 BC. Polished stone mirrors from central and south America around 2000 SM.Cermin age of shiny copper which has been made in Mesopotamia in 4000 BC and in ancient Egypt in 3000 BC. In China, bronze mirrors made in 2000 BC.
Metal-coated glass mirror was invented in Sidon (now Lebanon) in the first century AD, and mirror glass with the back of the gold leaf is mentioned by the author of the Roman Pliny in his Natural History book, which was composed around the year 77 AD The Romans also developed a technique creates a harsh mirror of blowing glass are coated with a molten tin.
Reflective parabolic mirror was first described by physicists from the Arab named Ibn Sahl in the 10th century. Ibn al-Haytham discussed the convex and concave mirrors in the geometry of the ball and tube, do some experiments with mirrors, and solved the problem of finding the point in a convex mirror at which a ray coming from one point is reflected to another point. in the 11th century, a clear glass mirror produced in Al-Andalus.
In the early Renaissance, European manufacturers perfected a method of coating glass with tin-mercury amalgam. The exact date and location of the discovery is unknown, but in the 16th century, Venice, a city famous for its keahilan make glass, the production center of the mirror using this technique. Glass mirror of that period used to be a very expensive luxury goods.
Justus Liebig discovered mirror reflective glass in 1835. The process involves the deposition of metallic silver coating on the glass through the chemical reduction of silver nitrate. The process of coating glass with a reflective substance (silvering) was adapted to mass-produce mirrors. Today, mirrors are often produced by vacuum deposition of aluminum (or sometimes silver) directly onto the glass substrate.
Awalmya mirror tiles or sheets made of polished metal, usually silver or copper metal when the shadow dipantullan back is to be seen but also of other metals when only used to focus the light.
Most Modern mirror consists of a thin layer of aluminum coated with glass fragments. This mirror called "elder back" (back silvered), in which the surface bounces viewed through glass tiles. Mirror with glass coating makes the mirror stand, but reduces the quality of the mirror because of the additional biasan front glass surface. Such a mirror reverses about 80% of incoming light. "The back of the" mirror is often painted completely black to protect the metal from abrasion.
Telescopes and other optical equipment using old mirror front "(front silvered), in which the reflective surface placed on the surface of the glass, which gives better image quality. Sometimes silver is used, but mostly uses aluminum mirror, which reflects short wave better than silver.
Front of the old mirror reflecting 90% to 95% of incident light.
Because of rusted metal in the presence of oxygen and moisture, the presence of old mirror surface needs to be replaced repeatedly to maintain quality. Another way is, of course, uses a vacuum to put this mirror.
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