Patent ID: 7635854
Filing Date: 2009-12-22
Classification: G01F

Abstract:
1. A method for optically measuring a level of the top surface of a fluid contained in a storage means, comprising the steps of: (a) providing a lidar apparatus and adjusting a line of sight of said lidar apparatus substantially perpendicular to said top surface, said lidar apparatus including means for: (b) computing a computed waveform from the plurality of said digital waveforms, each element of said computed waveform being given by the value of a statistical estimator of the variability of the measured signal amplitudes stored in the corresponding elements of the said digital waveforms, (c) locating in said computed waveform the signal echo returned from said top surface of a fluid, and (d) determining the vertical distance that separates said top surface of a fluid from said lidar apparatus from the position of said signal echo returned from said top surface.