Testing and analysing the characteristics of new double three-field iono-chamber / 中华放射学杂志

ABSTRACT

Objective To test and analyse the characteristics of double three field iono chamber developed by ourselves. Methods We tested the time characteristic, dose rate characteristic and X ray quality characteristic by using direct test method, and current characteristic, voltage characteristic and thickness characteristic of double three field iono chamber by using photograph test method with NERO 6000B test meter, RF 500 mA X ray equipment and so on. The results were analysed. Results The time characteristic and dose rate characteristic had satisfied linear scales(the return coefficients of linety scales were R =0.999 61 and R = 0.998 88 respectively). The X ray quality characteristic was steady (the maximum output variation was ? max ≤?5%). The good characteristics of current, voltage and thickness were found(the maximum variations of film density were ?D max ≤?0.01, ?D max ≤?0.15 and ?D max ≤?0.06 respectively). The excellent repeat was showed (repeating error of exposure time and dose were ?T max ≤?0.004 s and ?X max ≤0.01?10 -5 C/kg). Conclusion The performace of the new Iono chamber is excellent and steady, so it has practical value.