| At the end of 1960s, since the conventional optics system having the big volume, poor stability and difficulty of beam collimation could not satisfy the requirements of optical communication and optical information processing, people hoped to realize integrated optics circuits like the molectron. With the effort on it for several decades, some research productions have already displayed the important functions in the fields of communication, military, power, astronomy, sensors, etc. At the same time, integrated optics has been formed as a new subject with the cross-link of optics and pellicular electronics. The applied fields of integrated optics exist in many aspects. Besides optical communication, sensors, optical information processing and optical computers, they are still infiltrating into other fields, such as material science, optical instrument, spectrum research, etc. According to the emonstration effection of the integrated electronics, many scientists chose the potential researches and developed many kinds of integrated optical devices. Integrated optics, like the integrated electronics, will make a profound change of the information technology. Optical waveguides are the base of the integrated optical circuits. They are the carriers for rapidly transmitting optical signals in large quantities. As the elements for restricting and guiding the lights, their essential is that the refractive index of waveguides is higher than that of external medium. In the integrated optical devices, planar waveguides are not only important parts, but also the characterization of their parameters can supply necessary references for preparing the channel waveguides.In the thesis, the involved contents and present state of waveguides are firstly introduced. They include the preparing methods, charactering means and applications. In addition, it is summarized that the physical base about the planar waveguides consisting of Wentzel-Kramer-Brillouin (WKB) approximation, inverse WKB approximation, mode eigenvalue equation, the coupling principle of the waveguide and prism, etc. The main research works concentrate on the refractive-index profile and loss measurement of planar waveguides and preparation of ion-exchanged glass waveguides. We developed two new methods for measurement of the refractive index profile and loss, respectively. The Ag/Na ion-exchanged glass waveguides were prepared on the BK7 and Er3+/Yb3+ codoped phosphate glasses. The influences of process parameters are also investigated. The concrete contents are as follows. 1. Construction of refractive-index profiles of planar waveguidesBy making use of the prism-coupling principle and improved inverse WKB theory, it can realize the refractive-index profile determination of the whole planar waveguides. During the fewer-mode waveguide measured by a single laser, two mode types and external refractive indexes are changed with four different instances. The WKB characteristic equation for different mode types and external refractive indexes can be written as(1)where . In this equation is the mode turning point, is the effective index for the corresponding mode type (either TE or TM modes) and external refractive index and , is the refractive index at the surface of the waveguide, for and for , is the free-space wavelength and is the mode order. To make use of all measured data with the operating mode type and external refractive index of a waveguide in a single characteristic equation, the same effective-index function must be treated accordingly. We choose TE mode and air external index as reference and define an effective mode order, , as (2) Using the new variables , an effective-index function can be constructed by the iterative fitting of all the effective indexes measured with different mode types and external refractive indexes. Then the equation (1) can be written in the form (3)where is regarded as a continuous effective index function of , and the effective indexes o...
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