Can you place a color lens in front of a white LED and get effective emergency warning, as with traditional lighting technologies?
No. While you can place a color lens in front of strobe and halogen light sources, white LEDs do not perform the same way. Strobe and halogen light sources produce a broad spectrum of light. A portion of that spectrum filters through the color lens to deliver red, blue, amber and even green lighting. White LEDs generate a much narrower spectrum of light. Only a small, ineffective portion of that spectrum will pass through the color filter. However, monochromatic LEDs (for example, red, blue or amber) work extremely well when matched with the same color lens, transmitting over 86 percent of their original light output.
