Development in the instrumentation for counting and analysis of particle tracks in solids

There exists a bottleneck in the field of detection of ionizing radiations by tracks in solids, specifically in the counting and analysis of tracks in the detecting materials, which could be polymers, glasses and minerals. The purpose of this paper is to present an overview of the methods that have been developed for reading and characterizing of the tracks formed in the detectors in different laboratories, since the late 70s. The physical principles and implementation of each method are emphasized. Following the chronology of their initial use, the review includes, among others, the direct and simplest reading methods, such as optical microscopy, spark counting; more complex methods as electron microscopy, densitometry, electrical changes, partially computerized methods, such as automatic and automated counting systems; and the fully computerized methods, such as image processing and opto-electronic systems. In each case, the physical characteristics of the tracks, the etching process (chemical and electrochemical) and the applications are considered. (Author)