Nota bene for laser alignment...

It is important to be aware that your eyeglasses may give you achromatic effects!!!  When looking at the scattered light from amplified NIR laser off a business card, you will see both the fundamental (red) and the fluorescence from two photon absorption (blue).  If you wear corrective lenses, the two spots will not be superimposed, but actually appear to be spatially displaced.  The displacement will switch based on your position relative to the beam.  It is natural to make the incorrect assumption that the displacement is because your NIR has a nonuniform intensity leading to the fluorescence appearing brigher on one side.  CAREFUL! Make sure you look at the scatter from different positions and/or try (VERY CAREFULLY) to examine the scatter without your corrective lenses.