Extended Analog Output for Optical Power Meters
Applikationsberichte
Extended Analog Output Function
An analog output is included on some optical power meter instruments to indicate the strength of the input optical signal with an output voltage. This is often used as feedback for automated optimization routines like adjusting optical probes or aligning fiber connections. Instruments like the N7747C, N7748C and the 8162xC remote heads (and earlier models) provide this output signal directly from the analog detection circuit so this signal is always present at the BNC connector. The signal ranges between 0 and +2 V, linearly proportional to the input optical power in mW and dependent on the power range setting of the instrument. (The range setting determines the gain of the transimpedance amplifier.) So for example in the -10 dBm range, 100 µW optical power results in 1 V output signal, while 10 µW results in 0.1 V. This has been the standard analog output functionality.