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Horticulator Photosynthetic Active Radiation (PAR) Application Note Vorteile Horticulturevon LED-Beleuchtung in | Microcosm GartenbauanwendungenLED it grow! Dies hat zur Folge, dass der Wirkungsgrad sehr stark von den Wellenlängen zu hohe oder zu geringe Mengen liefern (Abbildung 5). Strompreisen abhängig ist (Abbildung 4). Mit steigendem Strompreis Außerdem kann die Lichtrezeptur nicht an eine Pflanzenentwicklung werden die Einsparungen bei der Implementierung eines LED- angepasst werden (Abbildung 6). Derzeit gibt es eine Reihe von Projekten, Beleuchtungssystems deutlich größer. die die Lichtrezeptur (und andere Parameter) auf die Wachstumsphase der Pflanze abstimmen. Dabei kommen Kameras zum Einsatz, meist im 4 Lichtqualität sichtbaren oder infraroten Bereich. Der ultraviolette Bereich (UVA und UVB, 280 bis 400 nm) ist derzeit ein sehr interessantes Thema im Der Hauptvorteil von LEDs liegt in der Möglichkeit, das Gesamtspektrum Pflanzenanbau. Sonnenlicht besteht aus 9 % UV (Prozent PPF), während des Lichts anzupassen und zu optimieren. Dies kann genutzt werden, um HID-Quellen einen festen Wert von 0,3 bis 8 % UV-Strahlung (Prozent die photosynthetische Effizienz zu erhöhen und zu verbessern und PPF) emittieren[10]. Mit LEDs lässt sich die Belichtung sehr einfach steuern. Entwicklungsphasen zu steuern[8] aber auch, um die Menge an Eine unzureichende UV-Strahlung kann bei einigen Pflanzenarten die ungenutztem Licht und1. damit Essence Energie zu of reduzieren. Light Aufgrund ihrer Entwicklung3. What unterbrechen does [11]a. HIDplant-Quellen need? haben eine minimale fernrote monochromatischen Leistung können mehrere LEDs mit Strahlung (710 bis 740 nm), die LEDs effizient erzeugen können. unterschiedlichen WellenlängenLight is the verwendet visible part werden, of the um electromagnetic art-, sorten- und DieThe Be dimportanteutung d eparameterr fernrote nis S Photosynthetictrahlung wird i n ANO004 erklärt. Grüne wachstumsspezifische spectrum"Rezepturen" and iszu essential konfigurieren for plant[9]. Dies growth. steht im LEDsPhoton (530 Flux bis or 580 PPF. nm) The werden PPF value normalerweise indicates the nicht direkt in LED- Gegensatz zu HID-QuellenEach mitplant einem responds festen differently Ausgangsspektrum, to different die in Leuchtenamount eingesetzt,of all photons da emitteddiese Wellenlängen from a light für die Photosynthese als Technology – Innovative structure einigen Wellenlängenwavelengths ausreichend and Licht intensities liefern of undlight. inEffective anderen wenigersource wichtigin all directions. angesehen werden. Allerdings durchdringen diese light recipes are important to obtain optimal Contact Multiple 1.0 plant growth, development and quality. Quantum N-Layer Well P-Layer Thermal Pad Gold 0.8 2. Why does a plant need Contact light? Substrate 0.6 Zener diode for ESD Vertical chip for perfect Ceramic substrate for low Light can be used to control: protection thermal stability and current thermal resistance Photosynthesis control 0.4 Morphology Flowering Relative PPF (arb.) *PPF: Photosynthetic Photon Flux 0.2 Secondary metabolites Rate of flow of photons Flavor and aroma within PAR. The amount of all photons emitted from a light 0.0 400 nm 450 nm 500 nm 550 nm 600 nmsource in650 all nm directions700 per nm 750 nm second. Wavelength Nonabsorbent material – Gold contacts – low corro- Small footprint – High Pressure Sodium Metal Halide Fluorescent Typical LED Recipe MSL level 2 sion, perfect solderability High emisson power Abbildung 5: Typische Emissionsspektren von Lichtquellen im Gartenbau. Der grün schattierte Bereich stellt das Aktionsspektrum der Light recipesPhotosynthese for dar, ddifferent.h. alle Peaks außerhalb developmental davon sind verschwendete phases Energie of plants Propagation Growth Flowering Added values of light Competitive advantages 1.0 1 1 0.8 0.8 0.8 for your crop Adjustable spectrum One footprint for all color 0.6 0.6 0.6 Increased production Plant adapted spectrum 0.4 0.4 0.4 Improved plant quality Full spectrum 0.2 0.2 0.2 Better plant consistency Low thermal resistance Relative Intensity (Arb.) 0.0 0 0 Shortening of the total growth cycle 400 nm 600 nm 800 nm 400 nm 600 nm 800 nm 400 nm 600 nm 800 nm Better plant uniformity Wavelength Better germination rate Abbildung 6: Mögliche Lichtrezepturen in verschiedenen Entwicklungsphasen von Pflanzen Energy savings www.we-online.de ANO003a // 2018-08-01 // RiB 3 Photosynthetic Active Radiation (PAR) 1,00 Our LEDs have been Chlorophyll A Chlorophyll B developed for custom- Beta Carotene Different light sources in comparison REDEXPERT – Horticulator 0,75 Phytochromes ized light solutions for PAR 1.0 each grower. 0,50 0.8 Perfect Quality – ) 0,25 b. 0.6 very high efficacy ar Absorbend of pigments (Arb.) ( Absorbend of pigments (Arb.) 3.0 μmol/J (Deep Blue) PF Applications P 3.6 μmol/J (Hyper Red) 0,00 ve 0.4 350 400 450 500 550 600 650 700 750 800 ti la 4.0 μmol/J (Far Red) Vertical farming WavelengthWavelength (nm) Re Indoor farming 0.2 Chlorophyll A | Chlorophyll B | Beta Carotene | Phytochromes | PAR* Grow box Intercanopy lighting There is a particular part of the radiation spectrum that is required by plants (spectral 0.0 Floriculture range 400–700 nm), called Photosynthetically Active Radiation or PAR. 400 nm 450 nm 500 nm 550 nm 600 nm 650 nm 700 nm 750 nm Wavelength Aquarium lighting High Pressure Sodium Metal Halide Fluorescent Typical LED Recipe The PAR region is traditionally used to represent the wavelengths of light used by plants. However, it is now known that plants also respond to wavelengths outside of this region. The shaded area represents the action spectrum of photosynthesis meaning any peak outside of this is wasted energy. 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