The AQ3105A* and AQ3140 are highly precise optical variable attenuators, ideal for measurement of optical loss characteristics and transmission error rates in evaluating single-mode fiber-optic communications equipment. The AQ3105A* and AQ3140 contain both a step attenuator and a continuous attenuator for precise optical level adjustments up to 65 dB. Non-reflective coating on the optical surface enables the AQ3140 to achieve the high return loss of 40 dB. This is suitable for measuring systems having optical devices like a light source that is susceptible to reflected light.

* AQ3105A was discontinued.