[en] A theory is developed for the interaction of an electromagnetic field with one-particle quantum-confined states of charge carriers in semiconductor quantum dots. It is shown that the oscillator strengths and dipole moments for the transitions involving one-particle states in quantum dots are rather large, exceeding the corresponding typical parameters of bulk semiconductor materials. In the context of dipole approximation it is established that the large optical absorption cross sections and attenuation coefficients in the quasi-zero-dimensional systems make it possible to use the systems as new efficient absorbing materials