Illumination system

1. A system for illumination of aquatic animal food which has been dispensed into a volume of water, the system comprising:

a feeding system, external to the volume of water, for dispensing food for the aquatic animals into the volume of water, whereby the food, once in the volume of water, travels in an overall average travelling direction, said overall average travelling direction defining a feeding axis in the volume of water;

a first illumination surface positioned in the volume of water and arranged to illuminate the feeding axis, the first illumination surface for emitting a first light in a first direction towards the feeding axis;

a second illumination surface positioned in the volume of water and arranged to illuminate the feeding axis, the second illumination surface for emitting a second light in a second direction towards the feeding axis;

wherein the first illumination surface and the second illumination surface are different surfaces and are arranged to emit light towards the feeding axis from substantially different directions; to thereby illuminate the food as the food travels in the direction of the feeding axis; and,

wherein the volume of water has an air surface and wherein the feeding axis is substantially normal to the air surface.

2. The system according to claim 1 , wherein the first illumination surface is defined by a first normal and the second illumination surface is defined by a second normal pointing in a direction different from the first normal and wherein the first illumination surface and the second illumination surface are secured such that a first normal of the first illumination surface and a second normal of the second illumination surface cross or intersect within the volume of water, substantially at the feeding axis.

3. The system according to claim 1 , wherein the illumination system comprises a plurality of illumination surfaces arranged in the volume of water, wherein the plurality of illumination surfaces are arranged at a plurality of polar coordinate angles with respect to the feeding axis, e.g. along a boundary of the volume of water.

4. The system according to claim 1 , wherein the first illumination surface and the second illumination surface are part of a wall at least partly surrounding the volume of water.

5. The system according to claim 4 , wherein the illumination system comprises one or more components, the one or more components providing the first illumination surface and the second illumination surface, wherein the one or more components contain one or more light emitting diodes.

6. The system according to claim 4 , wherein a first component comprises the first illumination surface and a second component, separate from the first component, comprises the second illumination surface.

7. The system according to claim 6 , wherein the illumination system comprises one or more components, the one or more components comprising at least one of a temperature sensor and an optical light sensor.

8. The system according to claim 7 , wherein the first illumination surface and second illumination surface are provided at a depth greater than 1 meter below a water surface of the volume of water.

9. The system according to claim 1 , comprising one or more first illumination surfaces extending in a depth direction along the feeding axis and one or more second illumination surfaces extending in a depth direction along the feeding axis, wherein the illumination system further comprises a controller configured for controlling light sources such that one or more optical characteristics of the light emitted from the one or more first illumination surfaces and the one or more second illumination surface vary in the direction along the feeding axis defined in the volume of water.

10. The system according to claim 9 , wherein the controller is configured for controlling the light sources such that the optical characteristics of light emitted from the one or more first illumination surfaces and the one or more second illumination surfaces are substantially equal at substantially the same depth in the volume of water.

11. The system according to claim 9 , wherein the first illumination surface and the second illumination surface are configured for providing direct illumination or contrast illumination of the food dispensed along the feeding axis.

12. The system according to claim 9 , wherein the first illumination surface and the second illumination surface are rectangular surfaces extending parallel to the feeding axis.

13. An arrangement for cultivation of aquatic animals, said arrangement comprising

a system according to claim 9 and

a food dispenser for dispensing food into the volume of water along the feeding axis; and

a water enclosure wherein the illumination system is arranged to illuminate the first and second illumination surface in the water enclosure and wherein the first illumination surface and the second illumination surface are arranged in the volume of water of the water enclosure.

14. The arrangement according to claim 13 , wherein the system comprises a controller adapted to control optical characteristics of light provided from the first and second illumination surface in accordance with the food dispensing.

15. The system according to claim 1 , wherein at least one of the first direction and the second direction is substantially perpendicular to the feeding axis.

16. A method for illuminating aquatic animal food which has been dispensed into a volume of water, the method comprising the steps of:

dispensing food into the volume of water by a feeding system that is external to the volume of water, whereby the food, once in the volume of water, travels in an overall average travelling direction, said overall average travelling direction defining a feeding axis in the volume of water;

emitting a first light in a first direction towards the feeding axis from a first illumination surface positioned in the volume of water;

emitting a second light in a second direction towards the feeding axis from a second illumination surface positioned in the volume of water;

wherein the first illumination surface and the second illumination surface are different surfaces arranged to emit the first light and the second light towards the feeding axis from substantially different directions; to thereby illuminate the food as the food travels in the direction of the feeding axis; and,

wherein the volume of water has an air surface and wherein the feeding axis is substantially normal to the air surface.

17. The arrangement according to claim 14 , wherein the controller is further adapted to control the food dispenser in dispensing food.