Radiophotoluminescence emission (RPL) and excitation (RPL-E) spectra of LiF:Mg,Cu,P and LiF:Mg,Ti sintered pellets, normally used as thermoluminescent (TLD) MCP-N and MTS-N detectors, were investigated following irradiations with various beta and alpha doses. The RPL spectra consist of two peaks: at 520 nm and at 670 nm, similarly as for undoped LiF single crystals. The radiation dose has however a significant influence on RPL spectra, as with the increasing dose a relative growth of the peak at 670 nm is observed. Alpha particle irradiation produces a relative increase of the peak at 520 nm, as compared with beta irradiation. Characteristics of LiF:Mg,Cu,P and LiF:Mg,Ti are similar but not identical. Especially dose response of 520 nm and 670 nm peaks for both materials is different. These differences should be taken into account if LiF TLDs are planned to be used as photoluminescence dosimeters.Excitation spectra for emission at 670 nm remains basically unchanged disregarding detector type, radiation type and dose. In case of emission at 520 nm the situation is different: increase of radiation dose results in broadening of the RPL-E spectrum or even in splitting of the main peak into two separate ones. The effect is observed for both LiF:Mg,Ti and LiF:Mg,Cu,P, while no such effects occur for undoped LiF single crystals.