SummaryThe possibility of the morphometric analysis of etched tracks, induced by protons and alpha particles in the organic polymer allyl diglycol carbonate (CR‐39), using the confocal scanning laser microscope (CSLM), was studied. The detectors were investigated in two groups of irradiation experiments, namely: (a) irradiated with mono‐energetic neutrons of energy 1–2 MeV, (b) exposed to the alpha radiation from222Rn and its progeny. Both groups were irradiated at normal incidence. Radiation‐induced latent tracks were electrochemically etched, and their morphometric parameters were investigated in the reflection mode by using the 488‐nm spectral line of an argon ion laser. A constant number of up to 200 optical sections in Z‐scan mode was taken through each selected etched track at vertical spacings of 0·642 μm. Successive reconstructions of Z‐sections were used to determine the following parameters: the mean radius of the opening channel, the maximum diameter and the length of the track, and the angle of the track wall to the surface of the sample. The results show that tracks produced by alpha particles differ from those induced by protons. The radius of the opening channel of alpha‐particle‐induced tracks ranges from 7·9 to 11 μm, whereas for protons the same parameter ranges between 2·0 and 3·8 μm for a specific electr