Emitter

Emitter may refer to:

Devices which emit charged particles

 * Cathode, or negative electrode, in a vacuum tube or diode
 * Anode, or positive electrode, in certain applications based on the emission of ions from a solid surface
 * One of the three terminals of a bipolar transistor

Devices which emit electromagnetic radiation

 * Lambertian emitter, a light source whose radiance varies with angle according to Lambert's cosine law
 * An infrared LED used to emulate a remote control

Other uses

 * A device used in drip irrigation
 * A compiler's code generator