Hi,
I am trying to measure the change of the refractive index (RI) of my sample by measuring the OPD with a QWLS wavefront senor. For this aim I have two different setups. My first setup is the combination of a routine upright microscope and my wavefront sensor, and the second setup is a simple combination of a light source (LED), a collimator, and the sensor.
The results obtained show that the measured value for Δn in these two setups are different. The comparison of the obtained values with the theoretical values confirms the values obtained with the second setup, but not the values obtained with the first one. Furthermore, I have obtained different OPD values for the measurement with different magnification, which I cannot understand.
I would be thankful if anyone could explain me, what is exactly happening in the measurement with the microscope, and how the different microscope parameters like magnification, NA,... affect the OPD.
Best regards,
Fatemeh
Dear colleague
please provide the scheme of your experimental apparatus so that one could help you
regards
Dear Dr. Anouar Jbeli ,
please find attached the scheme of my two setups.
Best regards,
Fatemeh
Dear colleague
the OPD is not influenced by magnification. only the width W of the sample and its refractive index n could influence the OPD.
if your OPD is between the situation before and after introducing sample then it is equals nW. you can measue it by determining the delay dt time between the two situation
you have : W = v*dt = c/n * dt then nW = c*dt = OPD
regards
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