Rapid track density determination of ssntd by frustration of total internal reflection of laser beam

Applications of the solid state nuclear track detectors (SSNTD) face the problem of rapid estimation of track density. While visual counting or the employment of sophisticated image analysis systems ensure accurate determination of number of tracks, other techniques are devoted to the non-expensive and fast assessment of the track density. In this work we present a fast, non-destructive method for estimation of SSNTD track density. It employs laser beam, which incident on the detector/air interface so that Total Internal Reflection (TIR) occurs on the smooth surface but not on the etched tracks. The experimental results suggest that in the present version the method gives reliable results for track densities ≥ l0³tr.cm^-2 (the sensitivity was determined to be about 500tr.cm^-2).