At present, the spectral patterns of plant lights on the market generally have the following forms:
Figure 1 white + red plant light
Figure 2 white + red plant light
Figure 3 multi-band plant light
Figure 4 red + blue plant lights
Figure 5 red green blue plant light
Among them, Figure 1 Figure 2 and Figure 3 are all called full spectrum. It is considered that the full-spectrum plant lamp is a illumination source for plant growth developed by simulating the solar spectrum. The concept of full-spectrum plant lamp is used to express its rich spectral components. The planting effect is better than other spectra. The solar spectrum of the wavelength of 350-800 nm is such that the simulation of such a spectrum has no application significance.
Regardless of the plant, the spectrum of sunlight is the least efficient for photosynthesis. Let us first talk about a key concept, that is, how is the “full” of the whole spectrum defined? Who defined it? How wide is the wavelength range to be called “full”?
Although the spectrum of sunlight is the most comprehensive, when studying the photosynthesis of plants under solar radiation, the wavelengths of PAR values used in countries all over the world are only described in the range of 400nm-700nm. Many LED plant lights claiming full spectrum. Adding UV and FR partial bands, as shown in Figure 2, Figure 3, but still using PPFD to represent the spectral parameters, since PPFD does not describe the amount of UV and FR radiation, micromoles less than 400nm and greater than 700nm are not included, this The PPFD value of the full-spectrum plant lamp ignores the already existing spectral radiation. In this regard, the nominal full-spectrum plant lamp sellers themselves are unaware of this low-level error.
The so-called full-spectrum plant lamp probably wants to describe the richness of the spectrum of the plant lamp. This “all” does not have a definitive definition. In the end, the wavelength of the large range is called “all”, and the current “full spectrum” is different. The definition range, the widest is 380nm-780nm, there is no uniform “full spectrum” definition, which means that everyone can define it themselves, so the “full spectrum” also shows a variety of spectral patterns.
So far, we have not seen which authority issued the “full spectrum” definition.
We believe that the full spectrum is a fuzzy concept for the description of the spectral shape. The wavelength range of the plant lamp is only the domain of the spectral photosynthetic efficiency function, not the value range of the photosynthetic efficiency function. The so-called full spectrum does not mean high photosynthetic efficiency and planting. The effect is good, and the purpose of propagating the full spectrum is to use the “full” meaning to render the plant light planting effect, which may lead to the misunderstanding of the plant lamp user.
The spectrum of plant lights is defined by the amount of light and light. The wavelength range of the plant lamp spectrum is still determined by the planting process of a certain plant. It is the definition domain of the planting process that determines the spectral design, not the planting based on the spectrum.
In the design of plant lights, there is only the spectrum theory, exaggerating the planting effect of the plant lamp spectrum, the spectrum is not the best, only the most suitable, this view of ours.
In order to study and communicate the spectrum, the Bright Light Source Research Institute classifies the spectral patterns of plant lights. We define two spectral patterns:
1) Continuous spectrum: in the domain of wavelength, the optical radiation power does not show zero value
2) Discontinuous spectrum: In the domain of wavelength, the optical radiation power shows a zero value.
Note: The zero value of the optical radiation power is not to reach the value zero. When the relative radiation power value <=0.002, it can be considered to reach zero value. The definition of this zero value indicates that the value has no effect on photosynthesis and light shape control.
Disclaimer: The continuous spectrum and the discontinuous spectrum are defined by Xu Dong, a research institute for bright and solid light sources, and the source needs to be indicated.
The concept of continuous spectrum and discontinuous spectrum is proposed to provide spectral shape classification for plant lamp spectral technology research. It is more scientific to analyze spectral data with similar spectral forms. Important parameters of plant lamps such as QE, PPF, YPF, PPFD and other parameters. The comparison needs to be made in these two spectral forms to make sense.
The continuous spectrum of the plant lamp does not have a good distinction with the discontinuous spectrum itself. Generally, the rationally designed discontinuous spectrum will be more efficient than the continuous spectrum, but the manufacturing cost is higher than the continuous spectrum.
According to our classification of spectral morphology, the current full-spectrum plant lamp is claimed to be either a continuous spectrum or a discontinuous spectrum.
For example, Figure 1 Figure 2 is the continuous spectrum we defined, Figure 3 Figure 4 Figure 5 is the discontinuous spectrum we defined. The full-spectrum plant lamp also refers to Figure 3 as the full spectrum.
The spectral patterns of plant lights are divided into continuous spectrum and discontinuous spectrum. It has an intuitive and clear image in technical communication and presentation, which is conducive to technical communication and product promotion. The application of plant lamps is also easier to understand.
The spectral technology of plant lamps is complex and requires a clear concept to describe. Plant lamp spectral design needs to avoid relying on imagination to design products and mislead consumers.
Full-spectrum plant lights are a false proposition, and this lack of technical basis can affect the development of plant lamp spectroscopy.