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To summarize, a headband was built with infrared LEDs in it with the purpose of shielding one's face from infrared "security" cameras mounted in public spaces.

This same concept could easily be applied to cars. It would be very simple and cheap to mount a bunch of these around a license plate.

I guess the only question is how often it would be useful. You guys probably know more about what technology the govts use than I do. Are infrared cameras used to hand out tickets?