Patent ID: 6091335
Filing Date: 2000-07-18
Classification: B64D

Abstract:
An optical device on board an aircraft and coupled to temperature and velocity sensors of the aircraft for detecting icing conditions, the device comprising:an optical beam emitter for emitting an optical beam to create at least one illuminated volume of measurement external to the aircraft through which flows air charged with water particles;a collector optical system for collecting a portion of light back-scattered by the water particles, wherein the volume of measurement is located on an optical axis of said collector optical system;photodetection means for detecting a varying polarization of the back-scattered light collected by the collector optical system over time to distinguish between liquid water particles and ice particles;a signal processor for processing a signal output by the photodetection means, a velocity received from the velocity sensors, and a temperature received from the temperature sensor to compute a severity of the icing conditions, wherein the severity of icing conditions is indicative of a water concentration multiplied by a speed of the aircraft; andmeans for providing information on the computed severity of the icing conditions, wherein the optical beam emitter is external to a back-scattering path of the back-scattered light.