In science, mirrors are often used in telescopes, lasers, industrial instruments and other instruments. Metal devices with regular reflective surfaces and glass or metal products with metal reflective films are often inlaid with metal, plastic or wooden frames.
Historical origin
The early days of slavery in China were in the Bronze Age. In the long-term bronze smelting and casting practice, people realize the relationship between alloy composition, properties and uses, and can manually control the proportion of copper, tin and lead.
The ancient book Kao Gong Ji recorded that "there are six kinds of gold", that is, the proportion of six alloys. The last one is together: "Gold and tin are half, which means it's the same." Is the proportion used to make bronze mirrors. "Sword" is a mirror with high tin content, because the bronze mirror has bright surface and silvery white color, and it also needs casting performance to ensure the fine pattern.
In the ancient Greek and Roman times in Europe, a slightly protruding polished metal plate was also used as a mirror, and its non-reflective side was engraved with patterns. The earliest mirror was a hand mirror with a handle. In the 1 century, there appeared a big mirror that could shine all over the body. In the Middle Ages, hand mirrors were popular in Europe, usually silver mirrors or polished bronze mirrors. In the middle ages, small mirrors in delicate ivory boxes or precious metal boxes became.