According to one embodiment, a system for transmitting an optical signal comprises a traffic distribution circuit configured to distribute traffic to a plurality of wavelength division multiplexer modules. The common inlet valve consists of a common inflow tube, which connects via tubing to the catheter where bodily fluids will enter the selective capacity chamber. The first lens includes a generally arcuate first lens surface and the second lens includes a generally arcuate second lens surface generally complementary in shape and in contact with the first lens.