LED plant growth lamp knowledge
Color temperature and lumen of biological light source
The color temperature and lumen of the artificial light source are seen by the eyes of the creature, and the plant's demand for light is the photosynthesis. This is determined by the radiation value without looking at the color temperature and lumen.
Effects of spectral range on plant physiology
280 ~ 315nm ––> This wavelength is already ultraviolet light. It has direct repressive growth for all kinds of animals, plants and even fungi, and has little effect on morphology and physiological processes.
315 ~ 400nm ––> This kind of light wave is also a far-ultraviolet light. Although there is no UV damage to plants, it has no direct effect on plant growth, and chlorophyll absorption is less, affecting photoperiod effect and preventing stem elongation.
400 ~ 520nm (blue) -> Such wavelengths can directly develop the roots and stems of plants, and have the largest absorption ratio of chlorophyll and carotenoids, and have the greatest impact on photosynthesis.
520 ~ 610nm (green) -> Green plant rejection push, the absorption rate of green pigment is not high.
610 ~ 720nm (red) –> The chlorophyll absorption rate of plants is not high, but this wavelength has a significant effect on photosynthesis and plant growth rate.
720 ~ 1000nm ––> These wavelengths are mostly infrared wavelengths. The low absorption rate of plants can directly stimulate cell elongation and affect flowering and seed germination.
>1000nm ––> The wavelength of the near-laser light has been converted to heat.
According to the above plant and spectral data, the light of each wavelength has different effects on plant photosynthesis. In the light required for photosynthesis, 400 ~ 520 nm (blue) light, and 610 ~ 720 nm (red) Photosynthesis contributes the most, while 520 ~ 610 nm (green) light has a low efficacy ratio for plants to grow.
According to the above principle, the plant has direct growth effects only for the spectrum of 400 ~ 520nm (blue) and 610 ~ 720nm (red). Therefore, the plant lights under the academic concept are made into a combination of red and blue, all blue, and all. Red three forms to provide red and blue wavelengths of light to cover the wavelength range required for photosynthesis in plants.
In terms of visual effects, the red and blue LED plant growth lights are pink. This kind of mixed light color is extremely uncomfortable for bio-lighting, but it can only be used for practical purposes. Sexuality.
Generally, white LED lamp beads, the most common is to use a blue core to stimulate the yellow fluorescent powder to illuminate, thereby producing a visual white light effect. There are two peaks in the blue region of 445 nm and the yellow-green region of 550 nm in the energy distribution on the integrating sphere test report.
The 610 ~ 720 nm red light required by plants is less able to cover the light efficiency required to supply light and function to plants. This explains why under the white LED illumination, why the plant growth rate and harvesting effect are not as good as the outdoor planting.
Using the above data, the ratio of red and blue light chromatograms of general plant lights is generally between 5:1 and 10:1, and the ratio of 7 to 9:1 is usually selectable. According to the light, the number of non-lighting beads is the basis of light mixing.
When using LED plant growth lamps for planting, the height of the leaves is generally about 30-50 cm. In the middle, it is necessary to give different light intensities depending on the type of planting plant. The height adjustment is generally regarded as the easiest way to adjust the brightness.