| Media optical rotation means that after light traversing throng this media, the polarizingplane will rotate an angle. The media which has optical rotation characters is named as opticalrotation media. Optical rotation mainly include quartz, liquid crystal, and optical activesubstance. The optical rotation characters are decided by the specific rotation dispersioncharacters of media, the specific rotation temperature characters, and the media attribute of leftrotation or right rotation. In traditional measuring method of media optical rotation characters,the specific rotation and the rotation attribute of left or right is measured by rotating polarizationanalyzer. Then, the specific rotation dispersion characters can be obtained by changing thewavelength of incident light. And the specific rotation temperature characters can be got bychanging the temperature of media. This method wastes time and energy. It goes against the realapplication in engineering. In the traditional method, the polarization analyzer should be rotatedagain and again. It is very easy introduce larger mechanical errors. In the progress of measuringthe specific rotation character, because after changing an incident light wavelength, thepolarization analyzer should be rotated again and the rotation angle should be measured againtoo. This make the measurement of the specific rotation spend very long time. The mediatemperature is very difficult to maintain certain. The changing of media temperature will inducethe specific rotation changing. And then enlarge the measurement error. In order to break throughthe limitations of the traditional method, a novel method is proposed. This method is based onspectral analysis, and the media optical rotation characters can be measured rapidly andaccurately by it. The new method is studied detailed and the related experimental facility isdesigned.This paper mainly includes the following research contents:1. A new measuring method of specific rotation dispersion character is proposed. Thismethod is based on spectral analysis. The correction of this method is verified by speciallydesigned experiment. The measuring method of specific rotation character is analyzed deeply intheory by using the polarized light interference theory, and the analytical method of matrix optics.The result shows: by this method, the polarized analyzer should not be turned, only usingspectral scanning, and analyzing the measured experimental data, the characters of specificrotation dispersion can be completed. Because the polarized analyzer is no need for turning,measuring time decreased substantially, meanwhile, measurement errors caused by mechanicalrotation is avoided. Because the measurement time is short, the temperature of medium is easy tokeep intact. Thereby, measurement errors caused by temperature fluctuation is decreased further.Based on the theoretical analysis results, using spectrophotometer, the experimental light path is designed. Taking quartz as an example, the specific rotation dispersion characters are measuredin experiment. By comprising the results and Lowry law which always used in engineering, thecorrection of this method is verified.2. The measurement method of specific rotation temperature characteristics is achieved andverified by experiments. Based on the theoretical analysis of specific rotation dispersioncharacter measurement method by using spectral analysis, the method of specific rotationtemperature characters measurement by spectral analysis is studded. The results show: byspectral analysis, the specific rotation temperature characters can be measured rapidly for anywavelength light in a certain wavelength scope. Similarly, in the measurement progress, only thespectral scanning is necessary, and the polarized analyzer rotation is not necessary. Based on theresults of theoretical analysis, a related confirmatory experiments is designed. In the experiment,a quartz crystal is taken as a measuring example. In the visible light scope (400nm-800nm), forany wavelength light, the temperature character from25degree to165degree is measured, andthe interval time is20degree. Compared with reported measurement results, the media specificrotation temperature character measurement correction is verified.3. The judgment method of left or right rotation property of media based on spectral analysisis proposed. By using Stocks vector and Muller matrix, the light path is analyzed. The approachof judgment left or right rotation property of media is found in theory. An experiment is designedbased on the theoretical results. The correction of the theoretical analysis is verified. Comparingwith traditional methods, this method has the advantages of simple operating and quickmeasurement.4. According to the need of experiment facility, a shear difference tunable parallel beamsplitting polarizer is designed. The light path in the polarizer is analyzed deeply in theory. Basedon the results of theory analysis, the structure parameters of every part of the polarizer isoptimized. And the design of shear difference tunable parallel beam splitting polarizer iscompleted. The tunable scope of shear difference is from40mm to180mm, and the ratio of twopolarized light intensity is less than1.25. Based on the designed shear difference tunable parallel beam splitting polarizer, aninstrument structure of studying media optical rotation characters by spectral analysis isproposed. Feasibility analysis and preliminary experiments are applied to lay the foundation forthe next step of the corresponding instrument design.The innovations of this paper are:(1) Based on the spectral analysis, a new method formeasuring the specific rotation dispersion character is achieved.(2) Based on the spectralanalysis, a new method for measuring the specific rotation temperature character is achieved.(3)Based on the spectral analysis, a new method to judge the left or right rotation property of optical rotation media is achieved.(4) A combined shear difference tunable parallel beam splittingpolarizer is designed.(5) Based on the shear difference tunable parallel beam splitting polarizer,an instrument structure of studying media optical rotation characters by spectral analysis isproposed. |
PDF Full Text Request