All You Need To Know About The Full Spectrum LED Grow Light
In daily life, you may hear about the term " Full-spectrum, Full-spectrum lights, and the benefits of full-spectrum lights. These are not new, but because there is no unified and recognized definition for these terms, It is difficult for us to understand all. By the way, we may don’t know if the benefits claimed are true or not. After reading this article, You will have a better understanding of full-spectrum, full-spectrum light, and the benefits of full-spectrum lights.
1、What is a full spectrum
2、What you need to know about full-spectrum light
3、Full Spectrum Light Myths
1、What is a full spectrum
The term “full-spectrum” is nothing new and was introduced around the 1960s. This is a marketing term created by light manufacturers in the lighting industry to describe the characteristics and uses of a certain type of light.
How did light manufacturers get the inspiration for the term “Full-spectrum”?
The answer is the solar spectrum.
Stefan Graf, director of Illuminart in Ypsilanti, Mich., once said.“The only true full-spectrum light source is the sun”.
As we can see，this is the spectrum of the Sun.
From this solar spectrum, we can see that：
（1）The Sunlight has a broad wavelength, covers visible light (red, orange, yellow, green, blue, Indigo Violet), and contains infrared and ultraviolet light.
（2）The visible light spectrum of sunlight is continuous.
The visible light spectrum shows the spectrum of red, orange, yellow, green, blue, and violet in turn.
What does a discontinuous visible light spectrum look like?
Take the spectrum of blue-red light for example. This is a discontinuous visible light spectrum. The visible light spectrum presents only the blue and red light, lacking orange, yellow, green, blue, and purple lights.
（3）The ratio of wavelengths in different ranges of visible light is relatively balanced
As we can see from the figure above，there are no gaps, drops, or spikes in the visible spectrum.
What does the one that is not balanced look like?
There are gaps, drops, or spikes in the visible light spectrum.
Now abstracted from the characteristics of the solar spectrum, strictly, a full spectrum should have a broad wavelength, covering red, orange, yellow, green, blue lights in the visible spectrum and a small amount of infrared light and ultraviolet light in the invisible spectrum and no gaps drops, or spikes in the visible lights spectrum.
However, in real life, it is difficult to make a spectrum that totally copies solar spectrum,meeting all the conditions above.
So If a spectrum is continuous, and has a broad wavelength covering visible light and invisible light, then it is called the “full-spectrum”.
2、What you need to know about full-spectrum light
There is no standard definition for“Full-spectrum light”.
Light manufacturers will create their full spectrum lights based on their customer's needs.
In general, a full-spectrum light is closest to the sunlight with "full-spectrum", Correlated color temperature grade is 5000K-7500K, and Color rendering index close to 100.
CCT： Correlated color temperature is a way to describe the light appearance provided by light. The CCT of the full spectrum light is usaually between 5000K and 6500K. The sunlight at midday is about 5600-6500k. the higher the temperature, the bluer the light, and the lower the temperature, the yellower the light.
CRI： Color rendering index is a standardized test developed by lighting manufacturers in the mid-20th century. It refers to the ability of the light emitted by a light source to reflect the real color of an object. The CRI of a full-spectrum light is about 96. The CRI of sunlight is defined as 100. The closer the CRI is to 100, the closer the light is to sunlight.
Full-spectrum lights are used in the fields of human health, plants, microorganisms, identification, data transmission, and so on.
Take plant growth lights as an example
Lack of sunlight will retard the growth of most plants. However, The plant growth light can expose more light to the plants when lacking light especially indoors or in winter. For most growers, there are many kinds of plant growth light to choose from, the most common ones are red-blue light、HPS growth lights and full spectrum LED grow lights.
(1) The red-blue grow light：
The red - blue growth light is made out of LED , which has the advantages of low energy consumption, being customizable for specific plant and giving off almost no heat.
It provides blue light with wavelengths between 450 - 495 nm、red light with wavelengths between 620-630nm.
Blue light can improve stems and leaves growth
Red light can improve flowers blooming, blossom and fruit
As shown in the figure below, chlorophyll (a) chlorophyll (b), and Carotene absorb lights mostly in the blue and red bands of the visible spectrum. In other words, blue light and red light are the most important lights for plant growth.
The red-blue light aims at providing the most needed lights(red light and blue light) for plants to make sure that they can better go through the process of photosynthesis and have the best growth state.
(2) HPS grow lights：
HPS(High-pressure sodium) grow light is a kind of gas discharge light. It uses sodium in the excited state to produce light. It has been used in agriculture for many years.
The color of the light is yellow. The price is relatively cheap and can provide many lights as the full spectrum LED grow light does, but relatively more red light and less blue light than the full spectrum LED grow light.
It is capable of producing a huge quantity of light, which is very important for flowering. In fact, because of this, a lot of farmers preferred HPS lights for years.
(3) Full-spectrum LED grow lights：
Like red-blue growth light, the full-spectrum LED grow light is made out of LED. Growers use it to grow plants mostly in a greenhouse and indoors such as agricultural research institutes, agricultural ecological parks, large office places, etc.
As shown in the figure below， the full spectrum LED grow light aims at providing light resembling sunlight.
The spectrum of full-spectrum LED grow light is continuous ( there are red, orange, yellow, green, blue lights in the visible spectrum ) and has a broad wavelength (it not only covers visible light (red, orange, yellow, green, blue, Indigo Violet lights) but also contains a small amount of invisible light ( near-infrared light(700~ 2,000nm）and ultraviolet A light（320-400nm）)
because of the technical restriction of LED industry, there are gaps, drops, or spikes in the spectrum.
What is the difference between full spectrum LED grow light and red-blue LED grow light?
The full spectrum LED grow light provides more lights than the red - blue light, such as green light, infrared light and ultraviolet light,with border wavelengths in spectrum.
The full spectrum grow light is more expensive than red and blue growth.
The color of red-blue light is pink or purple while that of the full spectrum grow light is white like the sunlight.
The full spectrum LED grow light produce more quantity of light than the red-blue growth light.
White light may be more comfortable to growers indoor，Since the color of red - blue plant grow lights is pink and purple, it may lead to dizziness, nausea and physical discomfort for growers indoor
What is the difference between the full spectrum LED grow light and HPS grow light？
The full spectrum LED grow light provides more blue light than the HPS growth light.
The price of full spectrum grow lights is higher than that of HPS grow lights.
3、The cost of maintenance
The later maintenance cost of full spectrum plant growth lights is relatively lower than that of HPS growth light while the purchase cost of full spectrum plant growth lights is higher than that of HPS growth light.
The service life of full spectrum growth light is longer, which can be used for 50000 hours. The ballast of HPS grow light is aging fast, which means that the lifetime of HPS growth light is not as long as that of full spectrum grow light.
It does not need to change the bulb frequently for the full spectrum LED grow light, while the bulb of HPS growth lights needs to be changed half a year, this requires additional labor and material cost.
the cooling device is usually needed to dissipate heat produced by the plant grow light. The full spectrum LED grow light generates less heat than the HPS grow light. It can cut down the additional electricity cost when using the full spectrum LED grow light.
The color of the full spectrum LED grow light is white while that of the HPS grow light is yellow.
5、Amount of heat
Providing the same quantity of light, the full spectrum grow light produces less heat than the HPS grow light does.
The full spectrum LED grow light is more energy-saving than HPS plant grow light.
The full spectrum grow light can be hanged more closer to the plants, while the HPS must be far away from the plants, otherwise it will burn to death.
There is no absolute conclusion about which kind of light is better.
The three types of grow lights have their own advantages and disadvantages.
It needs to be selected according to the specific plant;s species.
If we need to grow sun-requiring plants ,both HPS grow lights and full spectrum grow lights can be chosen, but full spectrum LED grow lights is preferred because it imitates the sunlight and saves more energy .
3、Full Spectrum Lights Myths
Many light manufacturers enthusiastically emphasize on the benefits of full-spectrum LED grow lights such as improving plant growth, achieving higher energy efficiency, and better replacement of sunlight. Are all of what they claim reliable?
According to some experiences and research, full-spectrum grow lights do have some benefits in some cases.
Improve plant growth
In the thesis 《Effects of different LED light sources on the growth and development of Tomato Seedlings》， Red light, full-spectrum white light, and fluorescent light (CK) are exposed to the tomato seedlings that to study the effects of different light sources exposed to the growth of tomato seedlings. The results showed that the tomato seedlings exposed with full-spectrum white grow light had darker leaf color, shorter and stronger bodies, well-developed roots, and a higher seeding index.
Provide more lights than non-full-spectrum light
Full-spectrum LED grow lights do provide more lights than non-full-spectrum growth lights, such as green light, infrared light, and ultraviolet light. These lights also affect plant growth, even if they are not as important as blue light and red light.
Green light can penetrate the crown of a plant better than the other wavelengths of light.
The infrared light can induce plants to avoid shadows, make them stretch out, and induce early flowering.
Ultraviolet light can induce protective compounds in plants.
However, manufacturers who selling full-spectrum LED grow light can make greater profits, some manufacturers and brands claim that their lights are "full-spectrum" despite they are not.
When choosing a full spectrum grow light, we had better check the spectrum、CRI and CT provided by the seller carefully since we are not able to tell the difference between them from the color appearance of the lights. If possible , we can also take the light we bought to the Professional institutions to get the exact spectral composition 、CRI and CT of the full spectrum light that we bought.
If you are looking for a best grow light that works best for planting cannabis, Photonican Aurora 2000 LED Grow Light will be your the best choice.
We believe cannabis need a quality spectrum that imitates the spectrum of sun to deliver quality yields. Photonican Aurora 2000 LED Grow Light has a full spectrum with invisible light（ red, orange, yellow, green, green, blue, and violet in turn）and small amount of invisible light( near infrared light and ultraviolet A light）
What’s more,our spectrum provide at least 30% more red spectrum output than most similar LED grow lights on the market,which can boosts for more yields and increases cycles in a year.