2. The polished rod is also called polished rod. Compared with the threaded rod, it has a smooth surface and no embossing. It is similar to the stainless steel rod and is a special tool for the laboratory. Used for scraping ink, coating preparation, etc. , no wet film thickness, used for scraping ink.
3. Optical cables are manufactured to meet the optical, mechanical or environmental performance specifications. It is a communication cable assembly, which uses one or more optical fibers placed in the sheath as the transmission medium and can be used alone or in groups. Optical cable is mainly composed of optical fiber (glass fiber as thin as hair), plastic protective sleeve and plastic sheath. There are no metals such as gold, silver, copper and aluminum in optical cables, so they generally have no recycling value.
Extended data:
In daily life, optical fiber is used for long-distance information transmission because the transmission loss of light in optical fiber is much lower than that of electricity in wires.
Usually, the terms optical fiber and optical cable are easily confused. Most optical fibers must be covered by several protective structures before use, and the covered cables are called optical cables. The protective layer and insulating layer on the outer layer of optical fiber can prevent the surrounding environment from damaging the optical fiber, such as water, fire and electric shock.
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