| 摘要 |
An optical multiplexer/demultiplexer with an improved spectral characteristic is provided by two diffraction gratings (21, 20) arranged optically in tandem and one being configured to embrace the other, the gratings also being arranged to provide free spectral ranges differing by a factor of at least two, and having a coupling (22') between them that carries over into the second grating information concerning the dispersion afforded by the first grating.
|
