Patent ID: 9363484
Filing Date: 2016-06-07
CPC Classification: G01B,G01C,H04N

Claim Text:
1. A method for range imaging, for determining respective distances to multiple objects contained within a field of view, based on a single captured image, the method comprising the following steps: /1/ obtaining a planar optical component having a transmittance t, said transmittance varying as a function of two coordinates (x, y) in a plane of the component, and having a two-dimensional Fourier transform T consisting of a finite number N of peaks located on a base circle of a radius ρ /2/ arranging the component perpendicularly to an optical axis Z oriented towards the field of view; /3/ arranging an image sensor in a plane perpendicular to the axis Z, at a distance d /4/ using the sensor to capture an image formed by light originating from the objects through the component; and /5/ calculating a Fourier transform of the captured image, in order to obtain a spectrum S /6/ providing a reference spectrum S /7/ in a common reference system, concentrically superimposing the spectrum of spatial frequencies of the captured image S /8/ digitally transforming, by a homothety centered in the common reference system, the reference spectrum S /9/ storing the homothety ratio H /10/ calculating the distance to one of the objects in the field of view, using the formula d repeating the sequence of steps /8/ to /10/ until it is no longer possible to perform step /9/ with a new value for the homothety ratio H i , each distance obtained during one of the executions of step /10/ corresponding to one of the objects contained in the field of view.