Tunable optical filter

摘要

The tunable optical filter comprises a Fabry-Perot cavity (12) and a controlled-index device (20). The controlled-index device is located in the Fabry-Perot cavity and has a refractive index responsive to a control signal (22). The Fabry-Perot cavity has at least one resonant optical frequency that depends on the refractive index of the controlled-index device. The Fabry-Perot cavity has a maximum transmissivity for light having a frequency equal to its resonant optical frequency, and attenuates light whose frequency differs from the resonant optical frequency. Thus, the control signal controls the frequency of the light transmitted by the tunable optical filter. <IMAGE>