I have power meter of the Ophir photonics, if I understand correct, it is based on the photon counting :
I=SP
where I is the electrical current, S is the responsivity, P is the power of the incident light.
I suddenly realized that I do not really understand which function it uses to perform back conversion from the measured current to the power which it displays. In my opinion there are two options (may be both of this options is not correct):
1)P_display=I_measured/S;
2)P_display=(I_measured)^2*R
where R is the virtual resistor based on value of the S;
Can anyboddy explain which option is correct. Good reference/link is welcome!
Thank you in advance!
I think the first option is correct. As far I understand the power meter is something which calculate power on the basis of no.of photoelectrons generated per sec,using a photo diode. then by using the equation I=SP(as you mentioned) , it will calculate current.
"Ophir provides two types of power sensors: Photodiode sensors and Thermal sensors. Photodiode sensors are used for low powers from picowatts up to hundreds of milliwatts and as high as 3W. Thermal sensors are for use from fractions of a milliwatt up to tens of thousands of watts.
Thermal sensors can also measure single shot energy at pulse rates not exceeding one pulse every ~5s."
(http://www.ophiropt.com/laser-measurement-instruments/laser-power-energy-meters/products/power-sensors)