| 摘要 |
<p>An optical device comprising a pair of facing semi-reflective layers (3, 5) forming a Fabry-Perot resonator wherein the spacing between the layers is slightly greater in a central region (9) of the resonator than in the surrounding area. As a result the divergence of light in an input beam applied to the device in the central region, and hence the linewidth of the transmission resonance of the device, is reduced. <IMAGE></p> |
