Converting Photodiode Signal to Laser Power

To determine incident laser power on a photodiode using the voltage from the photodiode (generally as measured with an oscilloscope), use:

[math]\displaystyle{ P=\frac{V}{(Amps/W) * (V/Amps)} }[/math]

With [math]\displaystyle{ V }[/math] as the potential difference from the photodetector with the laser on/off, and [math]\displaystyle{ Amps/W }[/math] and [math]\displaystyle{ V/Amp }[/math] as two conversion factors depending on the wavelength of the laser and the gain setting of the detector respectively.