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Extinction ratio is one of important parameters which are characterization of optical properties of Glan-Taylor prism (GTP) .In this paper, we adopt the ray tracing method to deduce the extinction ratio expression of the GTP. By performing the computer simulation, some important relationship curves are obtained as the variations of the extinction ratio on optical axes and the structural angle, the work has great guiding significance in the design and use of Glan-Taylor prism.

According to the common Glan-Taylor prism’s design feature, Fresnel formulae and Brewster’s law, a novel Glan-Taylor prism was designed and fabricated. In the new prism, the structure angles of second half were modified to proper values so that extraordinary ray is incident on with Brewster angle. In order to minimize the deviation angle of the new prism, an additional angle was designed. Theory and experiments have confirmed that the transmittance of the new prism is higher than that of a common one in a wide wavelength range and the interference effect will not occur in the new prism. Experimentally, its deviation angle is smaller than 3′ in the wavelength range of 540–670 nm.

A relatively simple efficient electrooptically Q-switched Er:Cr:YSGG laser oscillator-amplifier system in a line has been demonstrated. A Glan-Taylor prism and a cubic LiNbO3 crystal are used as the polarizer and modulator, respectively. Using the line scheme, one can adjust the system elements easily and achieve a good Q-switched-to-free-running pulse energy ratio of 75% and an energy amplification coefficient of 1.8. As short as 80 ns of the leading edge of a stable single pulse and 132 ns in FWHM with an energy of 24.5 mJ are generated. We also investigate the effects of the pump energy and the delay time on the postlasing, the stable single-pulse operation, the prelasing, the laser buildup time, and the Q-switched pulse width. The laser system demonstrated can be used for the effective ablation of soft and hard tissues.

Two types of electro-optically Q-switched Er:Cr:YSGG lasers with different polarizing mechanisms have been operated. For the one Q-switching and polarizing are realized with only a LiNbO3 crystal with both ends cut at Brewster's angle and for the other they are achieved by a cubic LiNbO3 crystal and a Glan-Taylor prism, respectively. The two schemes are compared with regard to both the mechanical and laser Q-switched properties.

The precise angle measurement and transmission technology have been widely used in the precision measurement, aerospace, military, biomedicine and other devices, which are based on the polarized light and magneto-optical modulation. This method has the characteristics of no rigid connection required, long distance transmission, high precision, etc. However, the azimuth information measurement method needs the assistance of complex servo tracking system according to the orthogonal extinction principle of polarization prism, meanwhile, the measurement time is longer, which reduces reliability and reaction sensitivity of the system. In order to improve the measurement accuracy and fast response capability of the system, a fast space goniometry method is proposed through the Wollaston prism polarizing beam splitter, with which the azimuth is directly calculated according to the two light intensities. The measurement time can be shortened, and the accuracy is improved by the use of magneto-optical modulation technology. The rapid space angle measuring system needs to realize the measurement function in a certain translation range, which requires the beam to have a certain coverage area in the receiving unit. However, the system is limited by size and volume of the device; we can only choose to expand the incident beam. Therefore, when the beam is incident onto the receiving unit, some incident angle and azimuth, that is, non-vertical incidence will be produced. However, the polarization of the non-vertically incident light passing through the system will change and polarization aberration exists, which will lead to measurement error. In this paper, the beam passes through the polarizing prism in a certain range of azimuths and incident angles, and the polarized light tracing method and the boundary condition of the electromagnetic field are used to study and simulate the polarization change and distribution of the outgoing beam. The changes of different incident azimuths and angles can be simulated through the translation of receiving unit, and the azimuths can be measured indirectly by using self-collimation theodolite and right angle prism. By comparing the measured azimuths under the translational and centering conditions, the influence of polarization aberration on the angle measuring system and the correctness of the theoretical analysis are verified. It is concluded that when the azimuth angle is 0, the measurement error is small; when the azimuth is 90, the measurement error is largest, meanwhile the measurement error will increase with the translation distance becoming longer (i.e., the incident angle). According to the comparison between the experimental data and the simulation results, the existing problems are pointed out, and the corresponding improvement measures are proposed. The results of this work have some significance in guiding the optimization of the system structure, and the further improvement inthe performance of the system.

The principle of the polarization interference imaging spectrometer （PIIS） developed in our laboratory is described. The principle of the beam splitting of Glan-Taylor prism which is one of the key components in the PIIS is analyzed. Using the ray-tracing method, we obtain the transmittance of Glan-Taylor prism at full angle of view. By computer simulation, we analyze the influence of the incidence plane, incidence angle and thickness of air gap on transmittance, and the dependence of the transmittance on wavelength is given in the spectral range which is required by the instrument system using Sellmeier dispersion equation. The transmittance of Grand-Taylor prism is tested in experiment, and the results are in good agreement with the theoretical results, so the correctness of the theory is verified.

Glan-Taylor prism is one of the most important polarization components of the new polarization interference imaging spectrometer developed in our laboratory. The principle of beam splitting and imaging of Glan-Taylor prism are presented. This paper deduces the propagation track of light in Glan-Taylor prism by ray-tracing method at random incidence angle and the theoretical expressions of image displacement and chromatic aberration are derived. The results will provide a theoretical basis for the study of new polarization interference imaging spectrum technology and the development of apparatuses.