Polarizing Prism Transmittance

With the continual development of polarizing technology, polarizers are increasingly wide used in technical fields of optical information processing, polarizing guidance, fibre-optic communication, optoelectronic detecting and optical sensor, etc. The function of polarizer is to transform non-polarized light into polarized one, which is the preparation for further modulation. With the sustaining development of modern optics, polarizing devices especially such as fine polarizing prisms are becoming more and more widely used. Light transmittance is one of the important parameters which indicate performance of polarizing prisms. Some workers at home and abroad have profoundly researched polarizing prisms on optimal design, view angle and extinction ratio in recent years. However, light transmittance of polarizing prisms and polarizing beam splitters was not researched profoundly enough except for some simple theoretical analysis and measurement on light transmittance of Glan-Tayor prism.Basing on past research, this paper ulteriorly gives some formulas which apart describe the relation between light transmittance of prisms and each of three parameters namely wavelength, temperature and incident angle. And some experiments are designed to validate the theoretical results. Generally, the main content is as follows:In the introduction, we summarized the ways producing polarized light, the fields of application, materials used and the primary forms of design of crystal polarizing prisms. The present research actuality to this field, the source of this research subject, and the sense of this research are also introduced. In the second chapter, firstly, we introduce part of the basic theory and the design principal of prisms;then we have a summary to the design of Nichol prism, and introduce the design of glued Glan-type polarizing prisms and air-spaced Glan-type polarizing prisms in detail;finally we summarized several polarizing beam splitters and phase delay devices.In the third chapter, according to Fresnel formula and geometrical ubiety, we get two formulas on light transmittance of polarizing prisms. Multiple-beam interference between two incision inclines of polarizing prism is considered in one formula and is not considered in the other formula. Then the theoretical relation between light transmittance of some polarizing prisms and each of three parameters as wavelength, temperature and incident angle is given in this paper.In the fourth chapter, on the basis of the formulas which are given in the third chapter, corresponding experimental systems are devised to verify our theory and laboratorial curves are painted. In addition, the relevant theoretical curves can also be gotten depending on the foregoing formulas. Considering all erroneous factors, we find the results verify our theory by contrasting the laboratorial curves with the theoretical ones.To get a all-sided study about light transmittance of polarizing prisms, in chapter five, we give the other factors which influence light transmittance of polarizing prisms except for wavelength, temperature and incident angle. The other factors contain technical process, absorbency and dispersion of material used of polarizing prisms, absorption of the glued medium, stress birefringent, etc.The original points of this thesis lie in:(1) A material formula which describes the relation between the refractive index of e ray of calcite and wavelength of visible light is given in this paper. Furthermore, a relational expression about light transmittance and wavelength of visible light is given. The variant tendency of the transmission spectrum of Glan-Tayor prism we get by spectrometer accords with the theoretical curve.(2) This paper gets the relationship between light transmittance of Glan-Taylor prism or Glan-Thompson prism and incident angle when abnormal incident beam is in the plane formed by incision incline normal and incident face normal. The coherent experiment is devised to validate the theoretical result. Otherwise, the connection between light transmittance of o ray or e ray that OEdouble escape prism exports and incident angle is also studied theoretically and experimentally in this paper.(3) The theoretical relation between the structure angle of Glan-Taylor prism and temperature is given in this paper. Then the change of light transmittance of Glan-Taylor prism along with temperature is discussed in this paper.