Entirely thin-film allpass coupled-cavity filters in a parallel configuration for adjustable dispersion-slope compensation

Conventional dispersion-slope compensation filters suffer from a fundamental tradeoff between the amount of dispersion-slope compensation and the compensation bandwidth. A novel multireflection device, composed of two coupled cavity filters in a parallel configuration is proposed that has an adjustable dispersion-slope independent of the compensation bandwidth. The device provides an adjustable dispersion-slope value between -6.7 and -35.7 ps/sup 3/ over a bandwidth of 3 nm. The center wavelength is adjustable over a 10-nm range.