LIGHTING ASSEMBLY

• US 20100259190A1
• Filed: 06/09/2010
• Published: 10/14/2010
• Est. Priority Date: 09/18/2009
• Status: Active Grant

• Current Assignee: Valoya Oy
• Original Assignee: Valoya Oy
• Inventors: AIKALA, Lars
• Granted Patent: US 8,549,787 B2
• Time in Patent Office: Days
• US Class Current: 315/294
• CPC Class Codes: A01G 7/045 with electric lighting
• CPC Class Codes: F21K 9/64 using wavelength conversion means distinct or spaced from the light-generating element, e.g. a remote phosphor layer
• CPC Class Codes: F21Y 2115/10 Light-emitting diodes [LED]
• CPC Class Codes: H01L 25/0753 the devices being arranged next to each other
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/0002 Not covered by any one of groups H01L24/00, H01L24/00 and H01L2224/00
• CPC Class Codes: H01L 33/50 Wavelength conversion elements
• CPC Class Codes: H01L 33/502 Wavelength conversion materials
• CPC Class Codes: H01L 33/504 Elements with two or more wavelength conversion materials
• CPC Class Codes: H01L 33/507 the elements being in intimate contact with parts other than the semiconductor body or integrated with parts other than the semiconductor body
• CPC Class Codes: H01L 33/54 having a particular shape
• CPC Class Codes: H01L 33/60 Reflective elements
• CPC Class Codes: H01L 33/62 Arrangements for conducting electric current to or from the semiconductor body, e.g. lead-frames, wire-bonds or solder balls
• CPC Class Codes: H05B 45/30 Driver circuits
• CPC Class Codes: Y02P 60/14 Measures for saving energy, e.g. in green houses

Abstract

A lighting fixture for facilitating plant growth and a light emitting component. The fixture comprises a single light emission source LED device which provides at least two emission peaks in the wavelength range of 300-800 nm and at least one of the emission peaks has Full Width of Half Maximum (FWHM) at least 50 nm or higher. The emission peaks of the LED match well with a plant photosynthesis response spectrum and is therefore particularly suitable for high efficiency artificial lighting.

Claims

1. A lighting fixture for facilitating plant growth comprising at least one Light Emitting Diode (LED) having

a) first spectral characteristics including a peak in the wavelength range from 600 to 700 nm and arranged to exhibit a full width of half maximum of at least 50 nm or more;

and

b) second spectral characteristics with a maximum of 50 nm full width of half maximum and arranged to exhibit a peak wavelength in the range from 440 to 500 nm.

2. The lighting fixture of claim 1, wherein the LED has a spectral characteristics with a freely adjustable peak in the wavelength range from 500 to 800 nm and arranged to exhibit at least 30 nm full width of half maximum.

3. The lighting fixture of claim 1 or 2, wherein the emission intensities of the first, second and optional third spectral characteristics of the LED are arranged to be adjustable.

4. The lighting fixture of claim 3, comprising a second LED with at least one spectral characteristics with maximum 50 nm full width of half maximum and a peak wavelength in the range of 400 to 500 nm and optionally second and third spectral characteristics arranged to have a freely adjustable peak wavelengths in the range from 450 nm to 800 nm.

5. The lighting fixture of claim 4, wherein there is a plurality of LEDs of the first and second type, the ratio of LEDs of the first type to LEDs of the second type being 1 to 100.

6. The lighting fixture of claim 5, wherein the PPF value of the fixture per Watt is 0.35 or higher.

7. The lighting fixture of claim 6, comprising an emission decay rate difference of the first and the second spectral characteristics amounting to less than 20% during the first 10,000 hours usage, more preferably during the first 25,000 hours usage.

8. The lighting fixture of claim 7, wherein the spectral emission characteristics;

intensity, peak wavelength and full width of half maximum are controlled with selection and concentration of phosphor material.

9. The lighting fixture of claim 8, wherein the spectral emission characteristics;

intensity, peak wavelength and full width of half maximum are controlled with type of blue emission characteristics of a LED chip.

10. The lighting fixture of claim 9, further comprising at least one electronic control system to switch the first and the second LEDs independently on and off or alternatively dim independently by 0-100% power.

11. The lighting fixture of claim 1, wherein

a) the first LED diode has first phosphorescent spectral characteristics comprising a peak wavelength in the wavelength range of 600 to 700 nm and is arranged to exhibit at least a full width of half maximum of at least 50 nm;

b) the first LED further having second luminescent spectral characteristics comprising a peak in the wavelength range of 440 to 500 nm; and

c) the first LED optionally having third phosphorescent spectral characteristics of a freely adjustable peak wavelength in the range of 500 nm to 800 nm range arranged to exhibit at least 30 nm full width of half maximum;

d) first emission intensities of the first, second and optional third spectral characteristics being adjustable in any ratio.

12. The lighting fixture of claim 11, comprising second LED with at least one luminescent spectral characteristics with maximum 50 nm full width of half maximum and peak wavelength in the range of 400 to 500 nm and optional phosphorescent second and third spectral characteristics having freely adjustable peak wavelengths in the range of 450 nm to 800 nm.

25. Use of the lighting fixture of claim 1 and/or 13 in providing light for at least one plant.

27. A method for enhancing plant growth wherein at least one lighting fixture of claim 1 and/or 13 emits light to at least one plant.

13. A lighting fixture for facilitating plant growth comprising a luminescent UV LED, optionally with external emission characteristics, said LED arranged to exhibit

a) first phosphorescent spectral characteristics with a peak wavelength in the range of 350 to 550 nm;

b) second optional phosphorescent spectral characteristics with a peak wavelength in the range of 600 to 800 nm;

c) third optional phosphorescent spectral characteristics with a peak wavelength freely adjustable between 350 and 800 nm;

d) the phosphorescent emission intensities of first, optional second and optional third spectral characteristics being adjustable in any ratio.

14. A light emitting component for facilitating plant growth, comprising;

a light emitting compound semiconductor chip; and

a light wavelength up-conversion phosphor which is deposited in direct proximity of the LED chip;

said component being capable of emitting two characteristic light emission peaks.

15. The light emitting component of claim 14, wherein the light wavelength up-conversion phosphor being formed by at least two phosphors mixed with each other.

16. The light emitting component of claim 14, wherein the light wavelength up-conversion phosphor is deposited directly on the surface of the LED chip or spaced out with other optical material.

17. The light emitting component of claim 14, wherein the light emitting compound semiconductor chip has a peak emission range of 440 to 500 nm.

18. The light emitting component of claim 14, wherein the wavelength up-conversion phosphor is arranged to convert part of the light emission energy emitted by the compound semiconductor chip to the high wavelength of 600 to 700 nm.

19. The light emitting component of claim 14, wherein the two characteristics light emission peaks are at 440 nm-500 nm and 600-700 nm, respectively.

20. The light emitting component of claim 14, wherein the two characteristics light emission peaks omit spectral characteristics one at least 50 nm full width of half maximum and another maximum of 50 nm full width of half maximum and both at different wavelength ranges.

21. The light emitting component of claim 14, wherein emission at a frequency of 300-500 nm is arranged to be generated by the semiconductor LED chip and emission at a frequency of 400-800 nm is arranged to be generated using complete or partial wavelength up-conversion provided by the light up-conversion phosphor of the LED chip radiation power.

22. The light emitting component of claim 14, wherein partial wavelength up-conversion is 5-95%, preferably 35-65%, of the semiconductor LED chip radiation.

23. The light emitting component of claim 14, wherein the light wavelength up-conversion phosphor is formed by at least two phosphors mixed with each other and further mixed into a third component selected from the group of solvents, inorganic or organic polymers, silicon polymers, siloxane polymers and other polymers.

24. The light emitting component of claim 14, wherein the phosphor or phosphors and the solvent or solvents together form an encapsulant when deposited on or close to the LED chip.

26. Use of the light emitting component of claim 14 in providing light for at least one plant.

28. A method for enhancing plant growth wherein at least one light emitting component of claim 14 emits light to at least one plant.