抄録
Three-dimensional optical waveguide with periodic structure is playing an important role in optical IC, and more accurate analysis on such waveguides with arbitrary number of periods is required. In this paper, revised Fourier series expansion method for larger number of periods and higher accuracy in which Floquet’s theorem is introduced is applied to numerical analysis of lamellar grating type periodic optical waveguides with rectangular cross-section (glass substrate). Referring to the numerical results, the characteristics for reflected and transmitted powers of guided and radiation fields vs. wavelength are investigated for various depths of the grating groove and for each number of periods(100-1000). Then the effects of the groove depth and the number of period on the powers of each mode are made clear, and the appropriate parameters preferred for the dominant guided mode propagation in the periodic waveguide concerned are exemplified.
