摘要 |
Optical interference filters are designed with harmonic elements that can be related to Fourier series approximations of desired filter responses. The harmonic elements can be fashioned as individual waveguides of an array arranged in various formats including planar or concentric geometries. The expansion coefficients of the Fourier series correspond to normalized power distributions among the waveguides, and the harmonic components of the series correspond to incremental optical path length differences between the waveguides.
|