Bi-directional optical communication modules and cables

A bi-directional optical communication module, comprising:

• a substrate;
• a first optical transmitter supported by the substrate and configured to generate a first optical signal having a first wavelength;
• a first optical receiver supported by the substrate and configured to receive a second optical signal having a second wavelength distinct from the first wavelength;
• and
• a tunable band pass filter supported by the substrate and communicably coupled to the first optical transmitter, the first optical receiver, and an optical port, the tunable band pass filter comprising a wavelength modification element configured to dynamically adjust a material refractive index of the tunable band pass filter in response to a control signal, wherein the dynamic adjustment configures the tunable band pass filter to:
• (a) pass the first optical signal from the first optical transmitter to the optical port;
• and
• (b) direct the second optical signal from the optical port into the first optical receiver.