英文:Any of several devices that convert incident electromagnetic radiation of mixed frequencies to one or more discrete frequencies of highly amplified and coherent ultraviolet, visible, or infrared radiation.
英文:A device used to modulate an electromagnetic wave.
中文:調制器用以調制電磁波的裝置
英文:An interconnected system for the distribution of electricity or electromagnetic signals over a wide area, especially a network of high-tension cables and power stations.
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