Full Spectrum Light,Full Spectrum LED Grow Lights
Full spectrum LED health lighting
Sunlight is the source of all things and is one of the necessary conditions for human survival. After millions of years of evolution, natural light has left a deep genetic imprint on human evolution. In people's work and life, the understanding of healthy lighting is to use artificial light sources that comply with photobiological safety to meet the requirements of lighting quality and non-visual effects, improve and improve the conditions and quality of people's work, study, and life, and promote mental and physical health. And achieve lighting applications with good visibility and comfortable and pleasant environment. Generally, people observe things under artificial light source lighting conditions. When the reflection spectrum of an item is different, a red apple has a stronger ability to reflect the red spectrum, a yellow lemon has a stronger ability to reflect the yellow spectrum, and the color temperature and color rendering under artificial light. Nature determines the reduction of light color. The light color displayed by the same item under different color temperature and color rendering index is different. If the color rendering index, color saturation, and color fidelity of the lighting LED are adjusted to close to 100, the light color will be closer to the sunlight. The more comfortable the human eye is, the more realistic the color displayed on the item will be. An important criterion is the agreement between the spectrum of the product and the spectrum of visible natural light. At present, the main technical applications for realizing full-spectrum health lighting in the industry are roughly divided into three types, using "single-band blue light chip + phosphor" to achieve full spectrum, "dual-band blue light chip + phosphor" to achieve full spectrum, and "Purple light chip + phosphor" deployment to achieve full spectrum.
Single Blue Light Chip Full Spectrum
When a blue light chip combined with a phosphor solution is used to produce a full-spectrum product with a low color temperature, a single blue light chip can excite green and red powder to obtain a full-spectrum LED with good spectral continuity and high color rendering. Its color rendering index CRI, color fidelity Both degree Rf and color saturation Rg can achieve greater than 97. It has the advantages of good stability, small blue light ratio and high batch yield, and is suitable for full-spectrum LED series products with large, medium and small power. High-color-temperature full-spectrum LED products are generally implemented using the "blue light chip + blue powder + green powder + red powder" technology solution. Due to the relatively low external quantum efficiency and poor stability of the blue powder, the full spectrum of this solution is not suitable for large For high power LEDs; high color temperature LEDs have high blue light radiation power, high requirements on the chip band, and difficult to increase the relative radiant power of the blue light parts, resulting in low yield of full spectrum LEDs with R12 greater than 90. In addition, the high color temperature LED spectrum has a large gap in the blue-green light region, and the spectrum continuity needs to be further improved.
Full spectrum of dual blue light chips
Based on the problems of using a single band of blue light to excite the phosphor to achieve the continuity of the LED's full spectrum and the color rendering index yield is not high, we have developed a full spectrum LED technology solution that uses multiple blue light chips to excite the phosphor. Up to 98 or even 99, the spectral continuity is better and the similarity with the solar spectrum is higher. The most important thing is that when using this technology to make a high color temperature solution, the blue light radiation power in the 430-450nm band is relatively low, and the blue light hazard level can reach RG0. However, the technology of this solution has higher requirements on the chip band and optical power, Difficulty of technical control.
Full spectrum of purple chip
The use of a 410-415nm short-wavelength purple chip to excite RGB mixed phosphors to achieve full spectrum has the advantages of good spectral continuity, low blue light radiation power, high similarity to the solar spectrum, and high index index. However, it is important to develop phosphors suitable for violet-excited phosphors to achieve high light efficiency and high stability. The existing blue powder technology has a lot of room for improvement in terms of stability and external quantum efficiency. At present, foreign technologies are relatively advanced and still require Relevant technical personnel research and development to achieve. In addition, the existing red powder has a problem of reabsorption of blue powder and green powder. The development of a new type of red powder that only absorbs or absorbs purple light is the key to achieving high-efficiency purple light full-spectrum technology.
Full Spectrum LED Technology Features
The spectral characteristics of a typical LED's full spectrum have a spectral power distribution curve of continuous light bands from red to blue (400 ~ 700nm), similar to the optical power distribution of sunlight at the same color temperature. The full spectrum simulates the natural light spectrum (of the same color temperature) and removes harmful ultraviolet and infrared rays from natural light. Compared with natural light, the integrity of the full spectrum should be close to the similarity of the natural light spectrum. Compared with ordinary LEDs, full-spectrum LEDs reduce the blue light peak, improve the continuity of the visible light band, and effectively improve the quality of LED lighting.
In the visible light band, the sensitivity to the human eye is extremely high and the similarity should be close. From the human vision bright and dark vision functions V (l) and V´ (l), it can be seen that the main color bands 470-650nm and The secondary color bands are 400-470nm, 650-700nm. In the 450-650nm band, we require the percentage of similarity to be above 0.95, and in the secondary bands 400-450nm and 650-700nm, the similarity is required to be above 0.70. The target spectrum is compared with the solar spectrum to indicate that it is natural The similarity M of the spectrum is calculated according to Equation 1.
Full-spectrum LED technical requirements
According to the results of the study, the completeness of the spectrum will affect the ability of visual color discrimination, especially in the development stage of children. The color fidelity, that is, the performance of color authenticity, characterizes the similarity of each standard color compared with the reference light source under the test light source. . Take the inverse of the target spectrum A (l) as an index of continuity. That is, the continuity C (l) = A (l) ′. The amplitude of the spectrum fluctuation can be limited by specifying the size of the different wavelength range C (l), and the spectral characteristics of the full spectrum can be standardized for the similarity of different light colors in the corresponding band As shown in Table 1.
|Light color||Wavelength (nm)||Similarity|
Usually similar to the solar spectrum, good spectral continuity, and high color rendering index, the color reduction ability of the object is higher. The measure of how well the color of the object under the measured light source matches the color of the object under the reference light source is the color rendering index. -rendering index). The color-rendering properties of light are compared with standard color cards, and the effect of LED light source on the color of the specified color chip is used to determine the quality of light-rendering. According to the full spectrum, which requires low blue light spectral characteristics, R12 in its color rendering index is a key indicator of saturated blue, and its value affects the relative spectral power of blue light in daylight-like light. The color rendering index Ra and R9 ~ R15 of the full spectrum should meet the requirements of Table 2.
|Ra||R1 ~ R8 average||> 95|
|R1||Light gray red||> 95|
|R2||Dark gray yellow||> 95|
|R3||Saturated yellow-green||> 95|
|R4||Medium yellow-green||> 95|
|R5||Light blue green||> 95|
|R6||Light blue||> 95|
|R7||Lilac blue||> 95|
|R8||Light purple||> 95|
|R9||Saturated red||> 90|
|R10||Saturated yellow||> 95|
|R11||Saturated green||> 95|
|R12||Saturated blue||> 90|
|R13||Caucasian complexion||> 95|
|R14||Leaves green||> 95|
|R15||Yellow complexion||> 95|
In terms of full-spectrum chromaticity performance, according to the recommendations of the International Commission on Illumination (CIE) and the definition of national standards, the chromaticity performance should meet the corresponding requirements in Table 3.
Rated correlated color temperature (K)
|Standard point coordinates||
Correlated color temperature CCT (K)
Color Tolerance (SDCM)
Typical Applications of Full Spectrum LED Lights
Full Spectrum Plant lighting: When determining that the current environment is a plant, the intelligent control system recognizes whether there is light that specifically regulates plant growth, and determines the type name of the plant through camera movement shooting, and then according to the type of plant and the current growth cycle. Control the parameters such as color temperature and illuminance of full-spectrum LEDs, and use light quantum efficiency to regulate plant growth. The influence of various wavelengths on plant growth: 280-315nm wavelength is ultraviolet light, which has the function of directly suppressing growth of various animals, plants and fungi; 315-400nm light wave is also far-ultraviolet light, which absorbs less chlorophyll and prevents stem extension Long; the wavelength of 400-520nm (blue) can directly develop the root and stem parts of the plant, which has the largest absorption ratio of chlorophyll and carotenoids and has the greatest impact on photosynthesis; the absorption rate of 520-610nm (green) green pigment is not high; 610-720nm (red) has a significant effect on photosynthesis and plant growth rate; 720-1000nm belongs to the infrared wavelength and has a low absorption rate for plants, which can directly stimulate cell extension and affect flowering and seed germination. Setting the light wavelength adjustment to excite a certain wavelength in the full-spectrum LED is beneficial to plant growth. For example, if potatoes are planted in a vegetable greenhouse, the full-spectrum LED light source at a wavelength of 400-520nm (blue) can be increased to increase yield. .
Full Spectrum Factory lighting: With the needs of industrial development, many factories need to adopt two-shift or three-shift working modes to meet production requirements. Based on the limitations of daylighting in the windows of the workshop, the disruption of workers' biological clocks is more prominent. The designer uses the outdoor light sensor to determine whether the factory is in day or night. During the day, the lighting is adjusted according to the physiological rhythm of the person, so that the workers can be in a full mental state. The intelligent control system can determine the typical value of a person's physiological rhythm according to the age of most workers. The camera tracks and recognizes the face to determine whether the current worker is in a fatigue state. If the number of fatigued people reaches a certain number, the spectrum can be used to mitigate it. Human fatigue. The application of full-spectrum LED lighting can reduce the visual fatigue of workers at work, thereby preventing brain fatigue, and improve work efficiency and product yield to a certain extent.
Full Spectrum Restaurant lighting: Based on the limitation of the restaurant where only the window surface can be lit, the designer uses a full-spectrum LED on the interior wall to simulate the scene outside the floor-to-ceiling window, which changes according to the effect of sunlight shining into the restaurant. The scheme design first determines the geographic latitude and longitude where the restaurant is located, obtains the local sunlight color, intensity, and time in each season, and uses cameras and sensors to monitor environmental sunlight changes and brightness information. During the day, the environment can be simulated according to the lighting spectrum. At night, the simulation picture adapted to the human's physiological rhythm is adjusted to make people who come to eat more pleasant and comfortable. When there are people in the restaurant, the lighting spectrum is activated to adjust the lighting and change the pattern according to the person's physiological rhythm. Based on the person's physiological rhythm, age, light and dark cycle, light exposure and other information, it simulates the day-to-day changes of the daylight and dynamically adjusts the color temperature, brightness, Lighting parameters such as illuminance provide dining customers with a comfortable dining environment and improve their dining experience. When the restaurant is empty, the full-spectrum LED is activated to emit light in the ultraviolet band to sterilize the environment.