I have been working on the mode matching lenses which are sitting after the boradband EOM.
Last Friday I checked the mode profile after the first mode matching lens (f=-150mm). The measured mode was good.
According to the calculation done by ABCD software, the waist size is supposed to be 80.9 um after that lens.
The measured waists are 80.5 um for the vertical mode and 79.4 um for the horizontal mode.
The screenshot of the ABCD's result and the plot for the mode measurement are shown below.
I didn't carefully check the mode after the last convex lens (f=200mm), but it must be already good because the beam looks having a long rayleigh range.
Now the beam is reflected back from MC1 and goes to the AP table since I coarsely aligned the beam axis to the MC.
/**** fitting result ****/
w0_v = 80.4615 +/- 0.1695 [um]
w0_h = 79.4468 +/- 0.1889 [um]
z_v = -0.115234 +/- 0.0005206 [m]
z_h = -0.109722 +/- 0.0005753 [m]