ASC PKG (2) Rainbow Cardboard Diffraction Grating Glasses. Great for Fireworks! RAINBOW GLASSES American Science and Surplus imprinted Neon strip cardboard spectacles with diffraction gratings as the lenses. You can see the regular world, but all light sources and bright objects appear in multiple rainbow hued images. The effect is a little as though the whole world were a giant hologram. Great stocking stuffer or birthday party item for grade school ages.