Plant growth lighting device and method
Embodiments described herein provide systems and methods for promoting plant growth that combine beam angle control with spectral control. In one embodiment, an optical device can be configured to emit multiple colors of light at particular wavelengths. The optical device may also be configured to generate an emission spectrum with multiple peaks. The spectrum can be selected based on stimulating biological processes of a plant.
1. A system for plant growth comprising:
a first LED device configured to emit light of a first color, wherein the first LED device is configured to emit light with a controlled beam half angle of less than or equal to 60 degrees and at least 50% of the light emitted by the first LED is in the controlled beam half angle of the first LED and at least 70% of the light emitted by the first LED is in the field angle of the first LED; and
a second LED device configured to emit light of a second color, wherein the second LED device is configured to emit light with a controlled beam half angle of less than or equal to 60 degrees and at least 50% of the light emitted by the second LED is in the controlled beam half angle of the second LED and at least 70% of the light emitted by the second LED is in the field angle of the second LED; and wherein the system is configured to generate an emission spectrum having a first emission peak below 500 nm and a second emission peak above 600 nm.
2. The system of claim 1 , wherein the first emission peak is at 425-475 nm, and a second emission peak is at 635-685 nm.
3. The system of claim 1 , wherein the system is configured to have a third emission peak at 500-600 nm.
4. The system of claim 3 , wherein the photon flux of the emission spectrum contains between 5% and 10% green light.
5. The system of claim 4 , wherein the photon flux of the emission spectrum contains between 5% and 30% blue light.
6. The system of claim 3 , wherein the photon flux of the emission spectrum contains between 10% and 20% green light.
7. The system of claim 6 , wherein the photon flux of the emission spectrum contains between 5% and 30% blue light.
8. The system of claim 3 , wherein the photon flux of the emission spectrum contains between 20% and 30% green light.
9. The system of claim 8 , wherein the photon flux of the emission spectrum contains between 5% and 30% blue light.
10. The system of claim 1 , wherein the emission spectrum has at least one emission peak in each of the blue, green and red regions.
11. The system of claim 1 , wherein the emission spectrum has emission peaks within at least three color regions.
12. The system of claim 1 , wherein the emission spectrum has emission peaks within at least four color regions.
13. A method of illuminating plants comprising: providing a first LED device configured to emit light of a first color, wherein the first LED device is configured to emit light with a controlled beam half angle of less than or equal to 60 degrees and at least 50% of the light emitted by the first LED is in the controlled beam half angle of the first LED and at least 70% of the light emitted by the first LED is in the field angle of the first LED; and providing a second LED device configured to emit light of a second color, wherein the second LED device is configured to emit light with a controlled beam half angle of less than or equal to 60 degree and at least 50% of the light emitted by the second LED is in the controlled beam half angle of the second LED and at least 70% of the light emitted by the second LED is in the field angle of the second LED; and illuminating plants using the system to generate an emission spectrum having a first emission peak below 500 nm and a second emission peak above 600 nm.
14. The method of claim 13 , wherein the first emission peak is at 420 nm to 470 nm, and a second emission peak is at 635 nm to 685 nm.
15. The method of claim 13 , wherein the system is configured to have a third emission peak at 500-600 nm.
16. The method of claim 15 , wherein the photon flux of the emission spectrum contains between 5% and 10% green light.
17. The method of claim 16 , wherein the photon flux of the emission spectrum contains between 5% and 30% blue light.
18. The method of claim 15 , wherein the photon flux of the emission spectrum contains between 10% and 20% green light.
19. The method of claim 18 , wherein the photon flux of the emission spectrum contains between 5% and 30% blue light.
20. The method of claim 15 , wherein the photon flux of the emission spectrum contains between 20% and 30% green light.
21. The method of claim 20 , wherein the photon flux of the emission spectrum contains between 5% and 30% blue light.
22. The method of claim 13 , further comprising dynamically changing the emission spectrum.
23. The method of claim 13 , wherein the emission spectrum has emission peaks within at least three color regions.
24. The method of claim 13 , wherein the emission spectrum has emission peaks within at least four color regions.
25. The method of claim 13 , wherein the system is operable to generate multiple spectra and the method further comprises selecting the emission spectrum for a particular type of plant being illuminated.
26. A method of illuminating plants comprising: providing a first LED device configured to emit light of a first color; providing a second LED device configured to emit light of a second color wherein at least 50% of the light emitted by the first LED and the second LED is in the controlled beam half angle of the first LED and the second LED and at least 70% of the light emitted by the first LED and the second LED is in the field angle of the first LED and the second LED; and illuminating plants using the system to generate an emission spectrum with multiple with emission peaks in at least four color regions and at least one of the emission peaks in at least one of the green region or the uv region.
27. The method of claim 26 , wherein the photon flux of the emission spectrum contains between 5% and 10% green light.
28. The method of claim 27 , wherein the photon flux of the emission spectrum contains between 5% and 20% blue light.
29. The method of claim 26 , wherein the photon flux of the emission spectrum contains between 10% and 20% green light.
30. The method of claim 29 , wherein the photon flux of the emission spectrum contains between 5% and 20% blue light.
31. The method of claim 26 , wherein the photon flux of the emission spectrum contains between 20% and 30% green light.
32. The method of claim 31 , wherein the photon flux of the emission spectrum contains between 5% and 20% blue light.
33. The method of claim 26 , further comprising dynamically changing the emission spectrum.