Philly cops used surveillance van marked 'Google Maps'

  It quoted a Kansas man with experience in public-safety 
  technology as saying the van contained gear including "infrared 
  cameras to find plate numbers and letters via temperature 
  differentials between those characters and the surrounding 
  background through optical character recognition."

This guy is confusing near infrared (0.75 µm) with thermal infrared. (8–15 µm)

Near infrared cameras are cheap. Thermal infrared cameras are expensive (exotic materials needed for the optics) and have poor resolution, which makes them a really poor choice for machine vision stuff. License plate cameras are near infrared.