Method for acquiring the shape of the iris of an eye

1 ) A method of acquiring the shape of the iris ( 102 ) of an eye ( 100 ), comprising:

a step of capture ( 112 ), by at least one image sensor ( 302 ), of at least one image of the iris ( 102 ), each image corresponding to the illumination of the iris ( 102 ) by a light beam ( 108 );

a step of constructing ( 114 ) the three-dimensional shape of the iris ( 102 ), reproducing its shape, from the image or images thus captured; and

a step of verifying the non-flatness of the three-dimensional shape of the iris ( 102 ) thus constructed.

2 ) An acquisition method according to claim 1 , characterised in that the construction step ( 114 ) comprises the following steps:

analysis, on the image or images captured, of the shades of light intensities generated by each light beam ( 108 ) on the iris ( 102 ); and

generation of the three-dimensional shape from the said analysis of the shades of light intensities.

3 ) An acquisition method according to claim 1 , characterised in that the direction of illumination of at least one of the light beams ( 108 ) forms a non-zero angle with the optical axis (X) of at least one of the image sensors ( 302 ), and in that the construction step ( 114 ) comprises the following steps:

analysis, on the image or images captured, of the shadows generated by each light beam ( 108 ) on the iris ( 102 ); and

generation of the three-dimensional shape from the said analysis of the shadows.

4 ) An acquisition method according to claim 1 , characterised in that the illumination of the iris ( 102 ) consists of a projection of a test pattern onto the iris ( 102 ), and in that the construction step ( 114 ) comprises the following steps:

analysis, on the image or images captured, of the deformations of the test pattern thus projected;

generation of the three-dimensional shape from the said analysis of the deformations.

5 ) A method of recording the three-dimensional shape of the iris ( 102 ) of an eye ( 100 ) in a database ( 306 ) of three-dimensional reference iris shapes, comprising the following steps:

three-dimensional acquisition of the shape of the iris ( 102 ) by an acquisition method ( 112 , 114 ) according to one of claims 1 to 4 ; and

recording ( 116 ) of the three-dimensional shape of the iris ( 102 ) in the database ( 306 ).

6 ) A method of identifying the three-dimensional shape of the iris ( 102 ) of an eye ( 100 ) from a database ( 306 ) of three-dimensional reference iris shapes, comprising the following steps:

three-dimensional acquisition of the shape of the iris ( 102 ) by an acquisition method ( 112 , 114 ) according to claim 1 ;

verification ( 118 ) of the non-flatness of the said three-dimensional shape of the iris ( 102 ) acquired; and

comparison ( 120 ) of the said three-dimensional shape thus acquired with the three-dimensional reference iris shapes in the database ( 306 ).

7 ) A device ( 300 ) for acquiring the three-dimensional shape of the iris ( 102 ) of an eye ( 100 ), adapted to implement a method according to of claim 1 to 4 , comprising:

illumination means ( 312 ) adapted to emit one or more light beams ( 108 ) onto the iris ( 102 );

at least one image sensor ( 302 );

means of constructing ( 304 ) the three-dimensional shape of the iris ( 102 ) from at least one image of the iris ( 102 ) captured by each image sensor ( 302 ).

8 ) A device ( 300 ) for acquiring the three-dimensional shape of the iris ( 102 ) of an eye ( 100 ), adapted to implement the method of claim 5 , comprising:

illumination means ( 312 ) adapted to emit one or more light beams ( 108 ) onto the iris ( 102 );

at least one image sensor ( 302 );

means of constructing ( 304 ) the three-dimensional shape of the iris ( 102 ) from at least one image of the iris ( 102 ) captured by each image sensor ( 302 );

a database ( 306 ) of three-dimensional reference iris shapes; and

means of recording ( 310 ) the said three-dimensional shape in the said database ( 306 ) of three-dimensional reference iris shapes.

9 ) A device ( 300 ) for acquiring the three-dimensional shape of the iris ( 102 ) of an eye ( 100 ), adapted to implement a method according to claim 6 , comprising:

illumination means ( 312 ) adapted to emit one or more light beams ( 108 ) onto the iris ( 102 );

at least one image sensor ( 302 );

means of constructing ( 304 ) the three-dimensional shape of the iris ( 102 ) from at least one image of the iris ( 102 ) captured by each image sensor ( 302 );

means of verifying the non-flatness of the three-dimensional shape of the iris ( 102 );

a database ( 306 ) of three-dimensional reference iris shapes; and

means of comparing ( 308 ) the three-dimensional shape of the iris ( 102 ) to be identified with the three-dimensional reference iris shapes.