Patent ID: 9128047
Filing Date: 2015-09-08
Classification: G01F,G01N,G08B

Abstract:
1. A method of detecting particles in an airflow including: receiving a signal indicative of light intensity scattered from the air flow at a plurality of wavelengths; processing the signal indicative of the intensity of received light at each of the wavelengths and a corresponding wavelength dependent parameter to generate an output signal indicative of at least one characteristic of particles in the air flow, including fitting at least one function to the signals indicative of the intensity of received light and corresponding wavelength dependent parameters; and determining an output signal indicative of at least one characteristic of particles in the air flow on the basis of a gradient at, at least one point on the at least one function, wherein the gradient is a ratio between the difference in intensity of received light at a plurality of wavelengths and the difference in the corresponding wavelength parameters at said plurality of wavelengths.