Flat Spectral Response Digital Micromirror Device-Based Variable Fiber Optic Attenuator

To the best of our knowledge, for the first time, an all-digital broadband variable fiber optic attenuator (VFOA) is demonstrated using the Texas Instruments' digital micromirror device (DMD) that does not use any narrowband or polarization-sensitive components. Simulations show that the proposed VFOA has a truly flat spectral response with a wavelength-dependent loss (WDL) of <;0.01 dB over the C-band 1530-1560 nm with a DMD designed to operate in the infrared. Experimental results show a WDL of ± 0.13 dB and a dynamic range of 38.6 dB with a visible DMD.