Imaging system for granular material with homogeneous background
An imaging system ( 100 ) including at least one camera ( 3 ), a background element ( 4 ) and a pair of mirrors ( 2 a, 2 b ), where the mirror surfaces of the mirrors in the pair are angled from each other at an angle α, where the imaging system ( 100 ) is intended to receive a sample along a main axis extending between the mirrors. The camera ( 3 ) is directed towards the mirror pair ( 2 a, 2 b ) and the background element ( 4 ) includes a surface directed towards the mirror pair, where the background element ( 4 ) is formed as a cylinder portion with a cylinder axis deviating from the main axis, and the mirrors are arranged with a respective mirror surface edge to edge with each other.
1. An imaging system ( 100 ) comprising:
at least one camera ( 3 ),
a pair of mirrors ( 2 a , 2 b ),
wherein the at least one camera ( 3 ) is directed towards the pair of mirrors ( 2 a , 2 b ),
wherein respective mirror surfaces of the mirrors in the pair of mirrors ( 2 a , 2 b ) are angled from each other at an angle α and the mirrors ( 2 a , 2 b ) are arranged with the respective mirror surfaces edge to edge with each other,
wherein the imaging system ( 100 ) is intended for receiving a sample along a main axis (V) extending between the pair of mirrors, and
a background element ( 4 ) formed as a cylinder portion with a cylinder axis deviating from the main axis,
wherein said background element ( 4 ) comprises a surface directed towards the pair of mirrors ( 2 a , 2 b ) and is placed within a field of view of the at least one camera ( 3 ) and an image to be taken by the at least one camera ( 3 ) through reflection in the pair of mirrors ( 2 a , 2 b ), and
wherein a division plane extends through the pair of mirrors and cuts straight through a position where the sample is being imaged by the at least one camera ( 3 ), substantially perpendicular to the main axis, where the at least one camera ( 3 ) is arranged on a first side of the division plane, and an entirety of the background element ( 4 ) is arranged on a second side of the division plane, and the at least one camera ( 3 ) is directed obliquely towards the position where the sample is being imaged so that no part of the at least one camera ( 3 ) itself is within the field of view of the at least one camera ( 3 ) and an image to be taken by the at least one camera ( 3 ) through reflection in the pair of mirrors ( 2 a , 2 b ).
2. The imaging system according to claim 1 , wherein the surface of the background element ( 4 ) that is directed towards the pair of mirrors is illuminated by at least one background illumination element ( 5 a - c ) directed towards this surface.
3. The imaging system according to claim 2 , wherein the at least one background illumination element ( 5 a - c ) is located outside of the field of view of the at least one camera ( 3 ).
4. The imaging system according claim 1 , wherein the imaging system is intended for receiving samples ( 1 ) with a typical colour and wherein the surface of the background element ( 4 ) that is directed towards the pair of mirrors has a colour which is substantially complementary to the typical colour of the samples.
5. The imaging system according to claim 4 , wherein the imaging system is intended for receiving seeds ( 1 ) and wherein the surface of the background element ( 4 ) that is directed towards the pair of mirrors is blue.
6. The imaging system according to claim 1 , wherein light is directed towards the respective mirror surfaces of the pair of mirrors from at least one sample illumination element ( 6 a , 6 b ), where the at least one sample illumination element is arranged above or below the pair of mirrors as seen from the main axis.
7. The imaging system according to claim 1 , wherein said background element ( 4 ) covers the entire field of view of the at least one camera ( 3 ).