Why do plants use LED plant-specific fill light instead […]
Why do plants use LED plant-specific fill light instead of other lights? What is the difference between led plant growth lights and ordinary LED lights, first of all, then we first look at various types of lights.
Incandescent lamp, the most commonly used lighting lamp in life. The principle of light emission is based on the phenomenon of heat radiation caused by the filament in a vacuum or neutral gas heated to an incandescent state through an electric current. The advantages are simple structure, low cost, convenient use and good brightness. Disadvantages are high heat generation, low luminous efficiency; short service life.
Tungsten halogen lamps are filled with an inert gas containing halogen elements (iodide) in the incandescent lamp body, and the luminous intensity and service life are improved by using the principle of the halogen tungsten cycle. Disadvantages are poor shock resistance.
Fluorescent lamp · (Fluorescent lamp·Energy-saving lamp) The principle is to use mercury vapor to generate a discharge under the action of an applied voltage, emit a little visible light and a lot of ultraviolet rays, ultraviolet rays stimulate the fluorescent powder coated on the inner wall of the lamp tube, so that it emits bright light. The service life and brightness are better than incandescent lamps. Disadvantages Long start-up time, there will be stroboscopic; affect service life.
LED fill light
LED (Light Emitting Diode); using solid semiconductor chip crop luminescent material, when the forward voltage is applied at both ends, the carrier fluid in the semiconductor recombines, releasing excess energy and causing photon emission to produce visible light. Advantages: high efficiency, pure light color, low energy consumption; long durability and long life; safe and environmentally friendly, instant start-up; anti-vibration, cold light source; low surface heat of the lamp body for a long time, good heat dissipation. Get close to objects without scorching them. Based on this feature, the LED can be placed horizontally or vertically above the plant. The disadvantage is weak brightness and high cost.
The main reason is that the light required for plant photosynthesis is different from the lights we use for daily lighting. Plant growth requires the use of the sun's light energy to assimilate carbon dioxide (CO2) and water (H2O) to produce organic matter and release oxygen, called photosynthesis.
Only the LED lamp can meet the above conditions, because only the LED lamp can emit the spectrum required for plant growth, and the plant must have appropriate light rays for photosynthesis. The spectral range has an important impact on plant physiology.
Let us look at the effect of different wave lines on plants:
280 ~ 315nm: minimal impact on morphological and physiological processes;
315 ~ 400nm: less chlorophyll absorption, affecting the photoperiod effect, preventing stem elongation;
400 ~ 520nm (blue): the absorption ratio of chlorophyll and carotenoid is the largest, which has the greatest impact on photosynthesis;
520 ~ 610nm (green): the absorption rate of pigment is not high;
610 ~ 720nm (red): The chlorophyll absorption rate is low, which has a significant effect on photosynthesis and photoperiod effect;
720 ~ 1000nm: low absorption rate, stimulate cell prolongation, affect flowering and seed germination>1000nm: converted into heat.
From the above data, the effect of different wavelengths of light on plant photosynthesis is different. The wavelength of light required for plant photosynthesis is about 400 ~ 720nm. Light from 400 to 520nm (blue) and 610 to 720nm (red) contribute the most to photosynthesis. The ratio of light from 520 to 610 nm (green) absorbed by plant pigments is very low.
According to the above principles, plant lights are basically made into three forms of red-blue combination, all-blue, and all-red to provide light of two wavelengths of red and blue, covering the wavelength range required for photosynthesis. In terms of visual effects, the red and blue plant lights appear pink.
When the LED plant fill light is used to fill the plant, the general power is less than 50wLED plant fill light. For different plants, the height from the main leaf surface of the plant is 0.2 to 0.8 meters; the power is higher than 50wLED plant fill light The lamp is aimed at different plants, and the height from the main leaf surface of the plant is 0.5 to 1.5 meters when it is used; in combination with the above situation; the LED lamp is the most suitable lamp for plant supplementary light.