I have an IR laser for which I want to find the TE (Transverse Electrical) vs. TM (Transverse Magnetical) mode. I know that the laser has linear polarization, and is configured for a single longitudinal mode with transverse mode close to TEM00. I have a polarizer (not exactly but nearby the wavelength of the laser) and a half-wave plate. Since the laser is in IR its hard to see the beam with your eyes. I can use a power meter but how do I know when its TE and TM? Any help would be very much appreciated.