LG-010 & LG-010N Laser Goggles spectral OD Curve. Wavelength is shown across the X axis and the Optical density (OD) is on the Y axis. The optical density number represents the number of zero's the eyewear attenuates the laser beam for a given wavelength. For example the LG-010/LG-010N spectral OD curve shows an optical density of OD 4 from 651nm to 670nm which is the equivalent of approximately 10,000 times attenuation of laser beams over these wavelengths. Contact us for assistance with your particular laser requirements.