Optical measuring device

1. An optical measuring device for spectral measurement of a sample, the optical measuring device comprising:

an integrating cavity at least a part of which has a diffusely reflective interior in order to render light in the integrating cavity diffuse;

at least one light source configured to emit light of a predetermined wavelength or predetermined wavelength range into the integrating cavity;

at least one sensor configured to receive the light from the integrating cavity;

wherein the integrating cavity comprises an optical opening;

wherein the optical measuring device is configured to measure a sample located outside of the integrating cavity directly in front of the optical opening;

further comprising a cover located inside the integrating cavity and configured to move within the integrating cavity so that no light passes through the optical opening; and

wherein the cover is located entirely inside the integrating cavity when moving from a position whereby the light passes through the opening to a position whereby no light passes through the opening.

2. The optical measuring device of claim 1 , further comprising a first light barrier is positioned on a direct path between the at least one light source and the opening; and

wherein the first light barrier is positioned such that the light from the at least one light source is prevented from directly reaching the opening and wherein the light from the at least one light source is reflected one or more times in the integrating cavity before reaching the opening.

3. The optical measuring device of claim 2 , wherein the light from the at least one light source is reflected two or more times in the integrating cavity before reaching the opening.

4. An optical measuring device for spectral measurement of a sample, the optical measuring device comprising:

an integrating cavity at least a part of which has a diffusely reflective interior in order to render light in the integrating cavity diffuse;

at least one light source configured to emit light of a predetermined wavelength or predetermined wavelength range into the integrating cavity, wherein the integrating cavity comprises an optical opening;

at least one sensor configured to receive the light from the integrating cavity; and

a second light barrier positioned on a direct path between the at least one sensor and the opening;

wherein the optical measuring device is configured to measure a sample located outside of the integrating cavity directly in front of the optical opening; and

wherein the second light barrier is positioned such that the light from the opening is prevented from directly reaching the at least one sensor and wherein the light reaching from the opening is reflected one or more times in the integrating cavity before reaching the at least one sensor.

5. The optical measuring device of claim 4 , wherein a third light barrier is on a direct path between the at least one sensor and light source; and

wherein the third light barrier is configured to prevent the light from the at least one light source from directly reaching the at least one sensor.

6. The optical measuring device of claim 5 , wherein a first light barrier is positioned on a direct path between the at least one light source and the opening, the first light barrier positioned such that the light from the at least one light source is prevented from directly reaching the opening and wherein the light from the at least one light source is reflected one or more times in the integrating cavity before reaching the opening; and

wherein a single structure consists of the first light barrier and the third light barrier such that the single structure is configured to prevent the light from the at least one light source from directly reaching the opening and configured to prevent the light from the at least one light source from directly reaching the at least one sensor.

7. The optical measuring device of claim 1 , wherein the at least one sensor is configured to generate data; and

wherein the optical measuring device is configured to determine, from the data generated by the at least one sensor, an indication of at least one of moisture, protein, lipid or carbohydrate in the sample.

8. The optical measuring device of claim 1 , wherein the optical opening comprises glass.

9. The optical measuring device of claim 1 , wherein the at least one sensor comprises a plurality of sensors; and

wherein the plurality of sensors have different spectral sensitivities.

10. The optical measuring device of claim 9 , wherein the spectral sensitivity is generated at least in part by optical filters positioned in front of the plurality of sensors.

11. The optical measuring device of claim 1 , wherein the at least one light source is configured to emit a broadband light spectrum.

12. The optical measuring device of claim 1 , wherein the at least one light source comprises a plurality of light sources; and

wherein the plurality of light sources are each configured to emit light with different wavelength ranges.

13. The optical measuring device of claim 1 , wherein the diffusely reflecting interior of the integrating cavity has a reflectance of at least 95% within the predetermined wavelength or the predetermined wavelength range.

14. A harvester comprising:

a feed device configured to receive harvested material gathered by an attachment;

one or more devices downstream from the feed device in order to process or convey the harvested material;

an optical measuring device positioned relative to or on the one or more devices and configured for spectral measurement of a sample, the optical measuring device comprising:

an integrating cavity at least a part of which has a diffusely reflective interior in order to render light in the integrating cavity diffuse;

at least one light source configured to emit light of a predetermined wavelength or predetermined wavelength range into the integrating cavity;

at least one sensor configured to receive the light from the integrating cavity;

a cover;

wherein the integrating cavity comprises an optical opening;

wherein the cover is located inside the integrating cavity and configured to move within the integrating cavity so that no light passes through the optical opening;

wherein the optical measuring device is configured to measure a sample located outside of the integrating cavity directly in front of the optical opening;

wherein the optical measuring device further comprises a first light barrier positioned on a direct path between the at least one light source and the opening; and

wherein the first light barrier is positioned such that the light from the at least one light source is prevented from directly reaching the opening and wherein the light from the at least one light source is reflected one or more times in the integrating cavity before reaching the opening.

15. The harvester of claim 14 , wherein the one or more devices comprise:

a chopping device downstream from the feed device and configured to comminute the harvested material from the feed device; and

a discharge device downstream from the chopping device and comprising a discharge spout; and

wherein the optical measuring device is positioned on the discharge device in order to measure at least one aspect of the harvested material as the harvested material is discharged.

16. The harvester of claim 14 , wherein the one or more devices comprise:

a threshing system downstream from the feed device;

a cleaning device downstream from the threshing system; and

a grain elevator downstream from the cleaning device and configured to guide the harvested material to a grain tank; and

wherein the optical measuring device is positioned on at least a part of the grain elevator.

17. The harvester of claim 14 , wherein the cover is located entirely inside the integrating cavity when moving from a position whereby the light passes through the opening to a position whereby no light passes through the opening.