emitter injection

例句：

1. 1.The device is an emitter of light.
   这个装置是光的发射体。
2. 2.The emitter is responsible for the emission of radiation.
   发射体负责辐射的发射。
3. 3.The emitter is a small device that emits sound waves.
   发射体是一个小设备，它发射声波。