Optical attenuators used in fiber optic communications systems may use a variety of principles for their functioning. Those using the gap loss principle are sensitive to the modal distribution ahead of the attenuator, and should be used at or near the transmitting end, or they may introduce less loss than intended. Optical attenuators using absorptive or reflective techniques avoid this problem. Because an air gap is subject to variations from contamination etc, attenuators without air gaps (based on doping etc) are more stable over time.
ConnectZone's Inline Fiber Optic Attenuator are used to lower the optical strentgth of your Fiber Signal."