Abstract
The efficiency and selectivity of the prism-coupler for exciting single modes in narrow planar optical waveguides is investigated both theoretically and experimentally. A previously published calculation of the coupling efficiency between a plane input wave with finite cross section and a number of waveguide modes, as a function of both the incidence angle and the skew angle, is extended to include the effects of diffraction, which are shown to play a dominant role for small focal widths of the input beam. The theoretical predictions are compared with experimental results obtained at 633 nm on an embedded ridge-type waveguide structure. A number of mechanisms reducing coupling selectivity and stability are discussed, and some practical rules are given for obtaining good stability and selectivity
| Original language | English |
|---|---|
| Pages (from-to) | 175-180 |
| Journal | Journal of Lightwave Technology |
| Volume | 7 |
| Issue number | 1 |
| Publication status | Published - 1989 |