| 摘要 |
<p>The present invention provides a method and apparatus for controlling the thermal response of guided wave Bragg grating devices (10) in such a way as to accentuate or annul the thermal response as desired or to otherwise control its properties. In one embodiment the method involves the imposition of a thermally dependent distribution of strains along the length of a Bragg grating in order to render its properties temperature insensitive or as nearly so as is the requirement. The method and apparatus can be used to control both the Bragg grating's inherent thermally sensitive properties as well as those thermal sensitivities produced by external tuning devices or packaging devices. The method of the present invention relies on the imposition of bending strains onto the element (32) to which the Bragg grating (10) is attached in response to a change in temperature. This can be achieved by elements (12) integral to, or mechanically or otherwise attached to the element (32) to which the Bragg grating (10) is attached. The configuration of the device and the material of which the elements are made provide for a wide range of thermal responses which allows for control of various Bragg grating properties.</p> |
