Vehicle occupant detectors

Abstract

In the field of vehicle occupant detectors there is a need for an improved vehicle occupant detector which is able to consistently identify the number of occupants in vehicles having windscreens with different infrared transmission characteristics. A vehicle occupant detector comprises a first infrared illuminator that is operable at a first infrared wavelength to illuminate an interior of a vehicle, and a second infrared illuminator that is operable at a second infrared wavelength to illuminate an interior of a vehicle. The vehicle occupant detector also includes a first infrared detector to capture a first image of the interior of the vehicle illuminated at the first infrared wavelength, and a second infrared detector to capture a second image of the interior of the vehicle illuminated at the second infrared wavelength. The first and second infrared detectors have the same infrared detection characteristics.

Dependencies are inferred from the claim text.