The emission methods of diagnostics are intended for obtaining the pos
ition, concentration, and area of the emitting plasma in plasma source
s of charged particles on the basis of the emission characteristics of
a source. The principal advantage of these methods is the absence of
any perturbing action on the object under study. The physical substant
iation and techniques for the realization of these methods are present
ed, as well as the results of the experimental study of electron sourc
es with a plasma emitter.