A comparative analysis of results of 2D simulation of the photoplasma parameters of a two-chamber Na Ar gas cell for the Doppler and Voigt contours of D1 and D2 lines of Na at the Na and Ar pressures 0.02 and 0.1 - 10 torr respectively is carried out. It is established that taking into account the broadening of these lines by the Na-Na and Na-Ar collisions is necessary and leads to significant differences as in the electron density and temperature so the photo-EMF.