Dear all,

I'm a green hand on LT-UHV Tip-Enhanced Raman spectroscopy(TERS). It's a type of photon-SPM which combine the Raman with the probe. Beam alignment is the most crucial procedure in photon-SPM and the beam needs to be accurately focused on the SPM junction. My problem is: I can't focus the laser properly. I wonder if there is a convenient and effective way for optical alignment, or only by repeated attempts. I really appreciate your suggestions!!