Plant illumination device and method for dark growth chambers

• US 9,485,920 B2
• Filed: 08/10/2015
• Issued: 11/08/2016
• Est. Priority Date: 03/17/2011
• Status: Active Grant

• Current Assignee: Valoya Oy
• Original Assignee: Valoya Oy
• Inventors: Aikala, Lars, Kivimaki, Ilkka
• Primary Examiner(s): RALEIGH, DONALD L
• Application Number:
  US14/821,923
• Publication Number:
  US 20150342126A1
• Time in Patent Office: 456 Days
• Field of Search: None
• US Class Current: 1/1
• 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: F21V 15/01 Housings, e.g. material or assembling of housing parts F21V15/02 takes precedence housings forming signs or letters G09F13/04
• CPC Class Codes: F21V 9/30 Elements containing photoluminescent material distinct from or spaced from the light source shades F21V1/17; globes, bowls or cover glasses F21V3/08, F21V3/12; refractors F21V5/10; reflectors F21V7/26, F21V7/30; elements with provision for controlling the spectral properties or intensity F21V9/40
• CPC Class Codes: F21V 9/40 with provision for controlling spectral properties, e.g. colour, or intensity
• CPC Class Codes: F21Y 2113/13 comprising an assembly of point-like light sources
• CPC Class Codes: F21Y 2115/10 Light-emitting diodes [LED]
• CPC Class Codes: H01L 2933/0083 Periodic patterns for optical field-shaping in or on the semiconductor body or semiconductor body package, e.g. photonic bandgap structures
• CPC Class Codes: H01L 33/06 within the light emitting region, e.g. quantum confinement structure or tunnel barrier
• CPC Class Codes: H01L 33/504 Elements with two or more wavelength conversion materials
• CPC Class Codes: Y02P 60/14 Measures for saving energy, e.g. in green houses

Abstract

An improved method to produce artificial light for plant cultivation, an illumination device with a semiconductor light emission solution and device suited for plant cultivation in a greenhouse and/or dark growth chamber environment are described. The best mode is considered to be a lighting device with LEDs that produces an emission spectrum similar to the photosynthetically active radiation (PAR) spectrum in a dark growth chamber. The methods and arrangements allow more precise spectral tuning of the emission spectrum for lights used in plant (310, 311) cultivation. Therefore unexpected improvements in the photomorphogenetic control of plant growth, and further improvements in plant production, especially in dark growth chambers, such as basements, are realized.

Claims

1. A light emitting component of a horticultural light in a dark cavity, comprising:

a light emitting diode (LED) semiconductor chip; and

a light wavelength up-conversion quantum dot or phosphor which is deposited in direct proximity of the LED semiconductor chip,

wherein the light emitting component is configured to emit two characteristic light emission peaks, and

the light emitting component is configured to reduce an emission at wavelengths of 500-600 nm below the intensity in the 400-500 nm band and below the intensity in the 600-700 nm band.

2. The light emitting component of claim 1, wherein the light wavelength up-conversion quantum dot or phosphor is deposited directly on a surface of the LED chip or spaced out with other optical material.

3. The light emitting component of claim 1, wherein the light emitting diode (LED) semiconductor chip has a peak emission range of 440 to 500 nm.

4. The light emitting component of claim 1, wherein the light wavelength up-conversion quantum dot or phosphor is configured to convert part of light emission energy emitted by the LED semiconductor chip to a high wavelength of 600 to 700 nm.

5. The light emitting component of claim 1, wherein the two characteristic light emission peaks are at 440 nm-500 nm and 600-700 nm, respectively.

6. A method for enhancing plant growth, comprising:

emitting, by the light emitting component of claim 5, light to at least one plant in a dark cavity, the light emitting component being the sole source of light.