Yuhang and Yuefan
Since now we have the reflected beam coming from the filter cavity, it has astigmatism of ratio almost 2 between two axes. And also, it was jittering while testing.
It is reasonable that the range is larger at yaw direction while smaller at pitch direction due to astigmatism.
Anyway, the galvo works well with some oscillation. I attach here a video. https://drive.google.com/open?id=1sxK1SRzyOSfxDVE6_rPHDkVkjddDbnPS