Wave Plate Retardation Of Temperature Effects

Wave-plate, which is also called phase retarder, is one of the most important optical devices in the modulation technology of polarized light and an important part of polarized devices. For the wave-plates, polarized light traveling in them will give birth to two vertical polarization branches with the same relative swings, so they play an important role in controlling and modulating the polarization of light and because of which, they are widely used and developed in laser technology and polarized technology. Phase retarder can achieve the interconversion in different polarization states and the turn of polarization plane when used with the others polarized devices.λ/4 andλ/2 wave-plates are two widely used wave-plates. Polarized devices are influenced by outfield especially temperature field when used, so is wave-plate. The optical capability of devices is influenced because of the change of both the refraction index and the appearance which are caused by the change of temperature.Refer to some reference literatures, the temperature effect of wave-plate is not studied by the numbers and most of the studies is under normal temperature and the influence caused by the change of temperature is not considered which influences the quality of the modulation of light because the retardation of wave-plate is obviously influenced by temperature, for example, for the 632.8 nm 23 levelsλ/4 quartz wave-plate, the retardation will reduce about 0.78°with the hoist of 1℃. If the relation between retardation and temperature is educed, corresponding measure can be adopted to decrease the negative influence caused by the change of temperature. For this purpose, the relation between retardation and temperature is studied in the article.Wave-plate can be divided into single wave-plate and complex wave-plate by category, both of the retardations will be influenced by temperature, so the temperature effect of them is studied. First, the temperature effect of familiarλ/4 wave-plate andλ/2 wave-plate are studied with intensity method and the experimental data is analyzed; second, effect of temperature on three-in-one composite compensator is studied; at last, the thermal expansion coefficient, which is the token of wave-plate's expansion is studied with interference method. The article is divided into the following parts concretely.The first chapter is introduction, in the chapter, the development of polarized devices and the temperature effect are introduced and the innovation work of the article is explained.The second chapter is basic knowledge of wave-plate, the structures and functions of both familiar single wave-plate and combined wave-plate are introduced respectively.The third chapter is the main part of the article. First, the temperature effect's theoretical analysis is done to bothλ/4 wave-plate andλ/2 wave-plate and the relations between retardations and temperatures are gotten, the results show that the retardation is descending with the hoisting of temperature and for the wave-plates with the same wavelength, the change is more obvious with higher levels; for the wave-plates with the same levels, the influence that the wave-plate with short wavelength is bigger than the one with long wavelength. Second, the temperature effect's theoretical analysis is done to three-in-one composite compensator, the results show that the retardation can achieve the modulation between 0 and 2πunder normal temperature, but when the temperature is changed, the adjustable range is reducing and the adjustable range is smaller with bigger temperature change which results in bigger influence, for the compensator composed of wave-plates with the same wavelength, the influence is more obvious with higher levels and for the compensator with the same levels but different wavelengths, the influence caused by the change of temperature for the compensator of short wavelength is bigger than the one of long wavelength. For different compensators, different calculations should be done to get the different change rules. At last, the thermal expansion coefficient is studied by theoretical calculation. The experimental projects are provided for the measurement of the above quantities.The forth chapter is the part of data processing and error analysis, in this part, experimental validations are done to the subjects with the projects provided. For the single wave-plate, the experimental data accords with the theoretical data well; for the three-in-one composite compensator, the change trend of experimental data is coherent with the theoretical data's, but does not tally well because of the existences of error; for the thermal expansion coefficient of quartz crystal, the warp between experimental data and existed data is 2.69%, the result is well. At the same time, theoretical analysis is done to the errors that may occur in experiment and integrated error analysis is done to quantities by the method of variance and standard deviation.The finally results comparing experimental data with experimental data show that they present the accordant trend which indicates that the result of the article is of value.