A New Optical Multichannel Analyser Using a Charge Coupled Device as Detector for Thermoluminescence Emission Measurements

The design and construction of a microprocessor-controlled optical multichannel analyser system is described. The system provides a means of real-time detection of the thermoluminescence emission in the wavelength range 380-880 nm, using a charge coupled device as detector operating at a data output rate of 210 kHz. The exposure time was varied between 25 ms and 100 ms. An interface and an analogue-to-digital converted were developed to record the output signal. For a constant heating rate, e.g., 10 oC.s-1, spectra may be recorded with a maximum number of 250 scans per readout at temperature intervals of 0.25 oC to 1 oC. Measurements were taken with CaF2:Dy (TLD-200) phosphors. Three main emission bands were observed at 410 nm, 483 nm and 572 nm.