A correlation method of nonperturbative control on energy spectra of negative (H−,D−) ions, profile, and transverse beam emittance at a bending transport line area, is suggested. The method is based on measurements of the cross correlation function between a photon flux from laser radiation, pseudorandomly modulated in time, and that of the fast (H°,D°) neutrals produced at a photon target and recorded on a drift distance. Characteristics of the apparatus for realization of the proposed diagnostical method at a source of H−(D−) ions by means of the time‐integrated correlators based on the charge‐coupled devices is considered.