The Models 2307 and 2317 large-area balanced photoreceivers take the headache out of aligning (and re-aligning) your beams onto the photodetectors. Now you can tweak your experiment without worrying about beam wander. And just like all our other balanced photoreceivers, they are ideal for coherent heterodyne-detection applications including doppler LIDAR, and can make the difference when you need to see a small signal.Just like our other balanced photoreceivers, the Models 23x7 balanced photoreceivers work by subtracting the photocurrent from two well-matched photodetectors. Common-mode noise that is present on both the reference and signal beams (such as laser intensity noise) is cancelled out and doesnt appear as part of the signal. Any imbalance between the photocurrents generated by the reference and signal photodetectors, whether intentional or unintentional, is ampliﬁed and is seen as the signal. These Models 23x7 photoreceivers provide higher gain than their wider-bandwidth balanced photoreceiver counterparts.For your convenience, the Model 23x7 balanced photoreceivers can run off batteries or your own DC power supply. To ensure safe operation, we strongly recommend our Model 0901 power supply.