الفهرس | Only 14 pages are availabe for public view |
Abstract Prepared laser dye solutions usually contain very small quantities of dye. Typical dye concentration are 10-a - 10” molar. For this reason, the solvent in which the dye is dissolved plays a major role when defining physical properties and potential hazards. The aim of the present work’is to study the macroscopic and microscopic physical properties of the most frequently used laser dye solvents (cyclohexane, benzene and chloroform). A new developed laser Mach-Zehnder interferometer (MZI) technique is used for measuring the absolute value of refractive index and its variation with temperature at the wavelenth 6328 A (4.74 x 1014 Hz). This technique is based on the shift of interference fringe pattern when rotating the sample in one arm of the interferometer. Accuracy of 1 x 10’~ is achived in the measurement of refractive index. The experimental results show that the sensitivity of the instrument (the number of fringes changes per one degree) in measuring the thermal coefficient of refractive index is equal to 9/K0 for cyclohexane, 12/~O for benzene and 10/KO for chloroform. The error of the refractive index caused by the temperature fluctuation is calculated where the data are fitted to the expression dr+ = (dn/dT)AT, where AT is the temperature change per fringe shift. This leads to dnT = 6.328 x lo-’ for cyc lohexane, benzene and chloroform. The refractive indices of the measured solvents show a linear relationship with temperature in the range of the experiment. The thermal coefficients of refractive indices are negative. |