| Dense wavelength division multiplexing has become a preferred technique for increasing the information-carrying capability of optical networks by making full use of the huge bandwidth available in optical fibers. In this approach, hundreds of optical channels are multiplexed at the transceiver end and separated at the receiving end, each operating at peak electronic speed. This dissertation focuses on grating-based DWDM, including holographic grating and ruled diffraction grating. Two eight-channel multimode grating-based DWDMs were designed and fully packaged. One of them utilized holographic grating; the other deployed a 22nd order echelle grating and had a thermally optimized optical design. The thermal responses of grating-based DWDM are analyzed and the solution for achieving athermal devices is given. Two ruled diffraction grating-based 32-channel DWDMs were fabricated and demonstrated. Both of them had low, uniform insertion loss; the typical crosstalk was better than −50dB for the single mode device. Finally the improved optical design and realization of passband broadening, and nonlinear correction of gratings' angular dispersion are described. |
