Phosphors - a substance which convert the absorbed energy into light. Currently, the phosphors are widely used in the manufacture of fluorescent lamps, plasma screen televisions for modern, luminous labels on signs and labels, labels to identify securities. The excitation spectrum is one of the most important characteristics of the phosphors. It is a dependence of the phosphor emission intensity of the emission wavelength, which excites the phosphor.
The problem or task
For the needs of the manufacturer of phosphors, it was necessary in a short time to develop a system for recording the excitation spectrum of phosphors. It was necessary to change the wavelength of the exciting radiation and record the intensity of the phosphor radiation.
To solve the problem, an automated recorder of excitation spectra of phosphors has been developed. A Shimadzu AQV-50 monochromator was used to change the wavelength of the exciting radiation. Initially, this device did not have an automated drive to change the wavelength. Therefore, a sweep drive was installed on the monochromator. It is based on the Fulling Motor FL57-STH56 stepper motor and the Geckodrive G210 driver. The sweep drive was controlled by the NI 9403 digital signal input / output module. The radiation intensity of the phosphor was measured with a PMT-62 photomultiplier tube with an amplifier. The signal from the amplifier output was recorded by the NI 9215 analog input module. The software was created in the NI LabVIEW programming environment. I / O modules are installed in the NI Compact DAQ 9174 chassis. The software runs on a personal computer. The developed recorder made it possible to automate the study of the excitation spectra of phosphors. The sweep drive control has expanded the functionality of the existing system for changing the wavelength of the exciting radiation. As a result, the time spent on the analysis of the sample of the phosphor is significantly reduced.