A red light-near infrared light LED device and its application

Abstract

The present invention belongs to the field of LED device preparation, and discloses a red-light - near-infrared light LED device and its application. The LED device is prepared by mixing a red-light - near-infrared light phosphor, transparent silica gel, and optionally a red phosphor, and encapsulating through an encapsulation process; the chemical formula of the red-light - near-infrared light phosphor is: A(B 1‑x Cr x )2O4, where A is at least one of Mg, Ca, and Sr, B is Ga and / or Sc, 0

Description

Technical Field

[0001] The invention belongs to the field of LED device preparation, and more specifically, relates to a red light-near infrared light LED device and application thereof. Background Art

[0002] The high-quality development of semiconductor light-emitting diodes (LEDs) is an important development direction at this stage. LED technology for plant lighting and ultraviolet sterilization is relatively mature at present, while LED technology for biomedical use is in urgent need of development, especially the preparation of red-near infrared LED devices. The reasons are as follows: Red-near infrared light has low single photon energy and strong penetration, which can meet the absorption and excitation of photoreceptors in organisms, so it can be used for disease treatment, especially for some diseases that cannot be fundamentally treated and prevented by drugs, such as neurodegenerative diseases, which require new treatment methods to fundamentally solve the problem. Among them, photobiomodulation (PBM) has great potential in preventing and preventing neuronal degeneration. Specifically:

[0003] Parkinson's disease (PD) and Alzheimer's disease (AD) are two common neurodegenerative diseases in the elderly, which seriously endanger human life and health and reduce the quality of life. The typical symptoms of PD patients are unique motor defects, including tremor, rigidity, akinesia and postural instability, which are usually associated with the loss of dopaminergic cells in the substantia nigra compacta of the midbrain. The typical symptoms of AD patients are cognitive defects, and the main pathological features are synaptic and neuronal degeneration, amyloid plaques and neurofibrillary tangles. In addition, mitochondrial dysfunction occurs in PD and AD patients in the early or late stages of the disease. At present, the medical community uses drug therapy to treat both diseases, but this method can only alleviate the symptoms of patients and cannot prevent or further stop neuronal degeneration. Many studies have shown that PBM can promote neurons to release the neurotransmitter dopamine, produce a large amount of ATP and enhance mitochondrial activity, and is considered to be the ultimate measure to fundamentally treat neurodegenerative diseases.

[0004] In addition to the above typical pathological symptoms, another major symptom of PD and AD patients is intestinal dysfunction. Often, the intestinal dysfunction symptoms of PD patients precede their typical motor defect characteristics. The "brain-gut axis" mechanism is a widely recognized view in the pathogenesis of neurological diseases. That is, the enteric nervous system connects the intestine to the central nervous system through nerves, hormone signals and immune signals, and the intestinal microbiome is an important signal source. Therefore, one of the current ways to treat neurological diseases is to take probiotics and achieve positive therapeutic effects.

[0005] It is generally recognized that light affects cellular energy metabolism, which is a mechanism of action of PBM. Specifically, light acts on cytochrome C oxidase (CCO) in mitochondria, increasing mitochondrial membrane permeability and transient increase in reactive oxygen species, activating mitochondrial signaling pathways related to neuroprotection and cell survival, and nitric oxide released by photodissociation of CCO and synthesis of CCO can stimulate vasodilation and blood flow, and promote ATP production by increasing oxygen consumption.

[0006] Light not only affects cell metabolism, but also regulates microbial activity. In addition to taking drugs to alleviate typical symptoms, an important strategy for the treatment of PD and AD is to regulate the patient's intestinal microbial configuration based on the "brain-gut axis" mechanism. Among them, lactic acid bacteria, as a typical probiotic, are of great significance for the treatment of PD and AD. Therefore, the use of PBM to regulate the microorganisms in the "brain-gut axis" is expected to complement conventional drugs and surgical treatments and produce positive therapeutic effects on neurological diseases.

[0007] Therefore, there is an urgent need to provide a new red-near infrared LED device that can meet the light source requirements for non-invasive PBM treatment of neurological diseases. Summary of the invention

[0008] The purpose of the present invention is to provide a red-near infrared LED device and its application in view of the deficiencies of the prior art. The red-near infrared LED device of the present invention can be used to treat gastrointestinal diseases, neurological diseases, and other probiotic supplementation diseases.

[0009] In order to achieve the above-mentioned object, the first aspect of the present invention provides a red-near infrared LED device, which is prepared by mixing red-near infrared phosphor and transparent silica gel, and optionally red phosphor, and encapsulating them through an encapsulation process;

[0010] The chemical formula of the red-near infrared phosphor is: 1-x Cr x )2O4, wherein A is at least one of Mg, Ca and Sr, B is Ga and / or Sc, 0 <x<0.10。

[0011] According to the present invention, preferably, the ratio of the amount of the red-near infrared phosphor, the amount of the red phosphor and the amount of the transparent silica gel is (1-3): (0-0.1):1.

[0012] According to the present invention, preferably, the chemical formula of the red phosphor is (Ca, Sr)AlSiN3:Eu 2+ , or, M2Si5N8:Eu 2+ , wherein M is at least one of Sr, Ca, Ba and Mg.

[0013] According to the present invention, preferably, the encapsulation process includes: defoaming and degassing a mixture of a red-light to near-infrared light phosphor, transparent silica gel, and optionally a red phosphor, and then titrating the mixture onto a blue LED chip, followed by baking and curing to obtain the red-light to near-infrared light LED device.

[0014] According to the present invention, preferably, the peak emission wavelength of the blue LED chip is 400 - 500 nm.

[0015] According to the present invention, preferably, in the chemical formula A(B 1-x Cr x )2O4, the value of x is: 0.0025 < x < 0.03, and more preferably, x = 0.01.

[0016] According to the present invention, preferably, the preparation method of the red-light to near-infrared light phosphor includes the following steps: First step: grinding and uniformly mixing a raw material containing Cr 3+ with a raw material containing element B, and performing a first calcination to obtain a first-step product;

[0017] Second step: grinding and uniformly mixing a raw material containing element A with the first-step product and a flux, and performing a second calcination to obtain a second-step product;

[0018] Third step: grinding the second-step product and then performing a third calcination, followed by crushing, grinding, washing, filtering, and drying to obtain the red-light to near-infrared light phosphor.

[0019] According to the present invention, preferably, in the first step, first incorporate Cr 3+ into the raw material containing element B, fully grind the raw material containing element B and the raw material containing Cr, and perform the first calcination in air or N2. The operating conditions include: heating at 3 - 10 °C / min to 850 - 950 °C, holding for 0.8 - 1.2 hours, then heating at 3 - 8 °C / min to 1400 - 1500 °C, holding for 1 - 5 hours, then cooling at 3 - 10 °C / min to 850 - 950 °C, holding for 0.5 - 2 hours, and then cooling at 3 - 10 °C / min to 250 - 350 °C, turning off the power, and cooling with the furnace to room temperature (25 - 30 °C).

[0020] According to the present invention, preferably, in the second step, the raw material containing element A and flux are added to the product of the first step, and then the product is fully ground and mixed evenly, and then dehydrated and degassed by low-temperature calcination (second calcination). The operating conditions of the second calcination include: heating to 100-300°C at 3-10°C / min, keeping warm for 0.5-2 hours, then heating to 500-1000°C at 3-10°C / min, keeping warm for 0.5-3 hours, then cooling to 250-350°C at 3-10°C / min, turning off the power, and cooling to room temperature (25-30°C) with the furnace.

[0021] According to the present invention, preferably, in the third step, the product of the second step is fully ground and then calcined for a third time. The operating conditions of the third calcination include: heating to 850-950°C at 3-10°C / min, keeping warm for 1 hour, then heating to 1100-1500°C at 3-8°C / min, keeping warm for 2-12 hours, then cooling to 850-950°C at 3-10°C / min, keeping warm for 0.5-2 hours, then cooling to 250-350°C at 3-10°C / min, turning off the power, and cooling to room temperature (25-30°C) with the furnace.

[0022] According to the present invention, preferably, the raw material containing element B is at least one of oxides, nitrates, oxalates and carbonates containing element B.

[0023] According to the present invention, preferably, the raw material containing element A is at least one of oxides, nitrates, oxalates and carbonates containing element A.

[0024] According to the present invention, preferably, the added amount of the flux is 1-2.5% of the total mass of the raw materials used to prepare the red-near infrared phosphor.

[0025] According to the present invention, preferably, the flux is at least one of aluminum fluoride, barium fluoride, ammonium chloride, ammonium fluoride, ammonium difluoride and boric acid, and preferably, the flux is boric acid.

[0026] According to the present invention, preferably, the emission wavelength range of the red-near infrared LED device is 600-1050 nm, and the peak emission wavelength is 700-730 nm.

[0027] The second aspect of the present invention provides the use of the red-near infrared LED device as a light source for treating gastrointestinal diseases, neurological diseases and juvenile myopia. In the present invention, the use of the red-near infrared LED device refers to a light source made using the device and a medical device and equipment made using the light source and further using the device and a light-emitting device. The application referred to in the present invention includes but is not limited to medical devices and equipment, and may also be other uses developed using the near infrared LED device made by the present invention.

[0028] The beneficial effects of the technical solution of the present invention are as follows:

[0029] (1) The light source generated by the red-near infrared LED device of the present invention has significant advantages over laser light sources, such as low cost and portability. In particular, its emission spectrum is a broadband spectrum, which is consistent with the broadband absorption of photoreceptors in biological bodies and is more suitable for PBM than the linear light of laser light sources.

[0030] (2) The research on light irradiation of lactic acid bacteria to regulate their activity using the red-near infrared LED device of the present invention showed a positive effect, further confirming its important reference value for regulating the "brain-gut axis" of neurological diseases.

[0031] (3) The red-near infrared LED device of the present invention can be used not only for medical light sources and equipment, but also for the treatment of gastrointestinal diseases, neurological diseases (stimulating the secretion and growth of dopamine and neurons, which is of great significance for the prevention, control and treatment of neurological diseases and complications such as Parkinson's syndrome and Alzheimer's disease), and other probiotic supplementation-related diseases, and can also be used for other purposes.

[0032] (4) The red-near infrared LED device of the present invention has a light output power of 53.71 mW and a photoelectric conversion efficiency of 18.08% at a driving current of 100 mA. The maximum light output power at a driving current of 20-320 mA is 111.9 mW and the maximum photoelectric conversion efficiency is 27.12%, reaching the industrial level.

[0033] (5) The red-near infrared fluorescent material used in the present invention has a spinel or spinel-like crystal structure. The emission wavelength range of the preferred fluorescent material is 600-1050nm, and the emission wavelength peak is 700-730nm; there are two excitation bands at 350-700nm, and it can be effectively excited by blue light; the absorptivity and internal and external quantum efficiencies of the red-near infrared fluorescent material are 35.4%, 81.1% and 28.7%, respectively.

[0034] (6) The light source emitted by the red-near infrared fluorescent material used in the present invention can promote the growth of intestinal lactic acid bacteria, the expression of anti-inflammatory factors, and the balance of intestinal flora in the body by regulating the activity of cells in the body, and has a preventive and therapeutic effect on the prevention and treatment of neurological diseases such as Parkinson's disease and Alzheimer's disease.

[0035] Other features and advantages of the present invention will be described in detail in the following detailed description. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] The above and other objects, features and advantages of the present invention will become more apparent through a more detailed description of exemplary embodiments of the present invention in conjunction with the accompanying drawings, wherein like reference numerals generally represent like components throughout the exemplary embodiments of the present invention.

[0037] Figure 1 The emission spectra of the red-near infrared phosphors provided in Examples 1-5 of the present invention are shown.

[0038] Figure 2 The excitation spectra of the red-near infrared phosphors provided in Examples 1-5 of the present invention are shown.

[0039] Figure 3 The present invention provides Mg(Ga 0.99 Cr 0.01 )The luminescence spectrum of the red-near infrared LED device encapsulated with 2O4 phosphor at different driving currents.

[0040] Figure 4 The present invention provides Mg(Ga 0.99 Cr 0.01 )2O4 phosphor encapsulation of the red-near infrared LED device with the change of current and the light output power curve.

[0041] Figure 5 The emission spectra of the red-near infrared phosphors provided in Comparative Examples 1-5 of the present invention are shown.

[0042] Figure 6 The excitation spectra of the red-near infrared phosphors provided in Comparative Examples 1-5 of the present invention are shown.

[0043] Figure 7 A comparison chart of the integrated areas of emission spectra of the red-near infrared phosphors provided by Examples 1-5 of the present invention and Comparative Examples 1-5 is shown.

[0044] Figure 8 The emission spectra of the red-near infrared phosphors provided in Comparative Examples 6-7 of the present invention are shown.

[0045] Fig. 9 The excitation spectra of the red-near infrared phosphors provided in Comparative Examples 6-7 of the present invention are shown. Fig.10 The emission spectra of the red-near infrared phosphors provided in Comparative Examples 8-12 of the present invention are shown.

[0046] Fig.11 The excitation spectra of the red-near infrared phosphors provided in Comparative Examples 8-12 of the present invention are shown.

[0047] Fig.12The emission spectra of the red-near infrared phosphors provided in Comparative Examples 13-16 of the present invention are shown.

[0048] Fig.13 The excitation spectra of the red-near infrared phosphors provided by Comparative Examples 13-16 of the present invention are shown.

[0049] Fig.14 The emission spectra of the red-near infrared phosphors provided in Comparative Examples 17-20 of the present invention are shown.

[0050] Fig.15 The excitation spectra of the red-near infrared phosphors provided in Comparative Examples 17-20 of the present invention are shown.

[0051] FIG. 16 ( a )-( b ) show the growth of lactic acid bacteria after 24 h of culture in a test example of the present invention (without illumination ( a ) and under illumination of 720 nm ( b ) ). DETAILED DESCRIPTION

[0052] The preferred embodiments of the present invention will be described in more detail below. Although the preferred embodiments of the present invention are described below, it should be understood that the present invention can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided to make the present invention more thorough and complete, and to fully convey the scope of the present invention to those skilled in the art.

[0053] In the following embodiments, the raw materials used to prepare the red-near infrared phosphor include: MgO (98.5%), CaCO3 (99%), SrCO3 (99%), Sc2O3 (99.99%), Ga2O3 (99.99%) and Cr2O3 (99.99%).

[0054] In Example 1-5, the chemical formula of the red-near infrared phosphor is: Mg(Ga 1-x Cr x )2O4, x are 0.0025, 0.005, 0.01, 0.02 and 0.03 respectively.

[0055] Example 1, x=0.01

[0056] This embodiment provides a red-near infrared LED device, which is obtained by degassing and degassing a mixture of red-near infrared phosphor and red phosphor mixed with transparent silica gel, then titrating it on a blue LED chip with an emission wavelength peak of 450nm, and then baking and curing it;

[0057] The ratio of the amount of the red-near infrared fluorescent powder to the amount of the red fluorescent powder to the amount of the transparent silica gel is 1.8:0.01:1.

[0058] The chemical formula of the red phosphor is (Ca, Sr)AlSiN3:Eu 2+ .

[0059] The chemical formula of the red-near infrared phosphor is: Mg(Ga 0.99 Cr 0.01 )2O4, its emission spectrum and excitation spectrum are as follows Figure 1 , 2 shown.

[0060] The synthesis steps of the red-near infrared phosphor are as follows:

[0061] The first step is to convert Cr 3+ Add into the raw material containing B element, fully grind the raw material containing B element (Ga2O3) and the raw material containing Cr (Cr2O3), and carry out the first step of calcination in air. The operating conditions include: heating to 900℃ at 4℃ / min, keeping warm for 1 hour, then heating to 1400℃ at 4℃ / min, keeping warm for 2 hours, then cooling to 900℃ at 4℃ / min, keeping warm for 1 hour, then cooling to 350℃ at 4℃ / min, turning off the power, and cooling to room temperature with the furnace.

[0062] In the second step, the raw material (MgO) containing element A and flux (H3BO3) are added to the product of the first step, and the mixture is fully ground and mixed, and then dehydrated and degassed by low-temperature calcination (second calcination). The operating conditions of the second calcination include: heating to 176°C at 4°C / min, keeping warm for 2 hours, then heating to 900°C at 4°C / min, keeping warm for 2 hours, then cooling to 350°C at 4°C / min, turning off the power, and cooling to room temperature with the furnace.

[0063] The third step is to grind the product of the second step sufficiently and then calcine it for the third time. The operating conditions of the third calcination include: heating to 900°C at 4°C / min, keeping warm for 1 hour, then heating to 1300°C at 4°C / min, keeping warm for 7 hours, then cooling to 900°C at 4°C / min, keeping warm for 1 hour, then cooling to 350°C at 4°C / min, turning off the power, cooling to room temperature with the furnace, and crushing, grinding, washing, filtering and drying to obtain the red-near infrared phosphor.

[0064] In combination with Examples 1-5, and by Figure 1 , 2 It can be seen that when Cr 3+ When the concentration is x = 0.01, the emission wavelength peak is at 717nm, which is the strongest. 3+ The significant changes in concentration are due to different concentrations of Cr 3+Entering the crystal lattice may occupy different lattice positions, changing the crystal field strength and affecting the Cr in the phosphor. 3+ of 4 T 2g (F) → 4 A 2g (F) Transition has a greater impact, while 2 E g (G) → 4 A 2g The spin-forbidden transition of (F) is less affected by changes in the crystal field strength.

[0065] Cr 3+ When the concentration is x = 0.01, Mg(Ga 0.99 Cr 0.01 )2O4 phosphor packaged red-near infrared LED device, under 100mA driving current, the device reaches the strongest emission at 718nm, at which time the device's light output power is 53.71mW, and the photoelectric conversion efficiency is 18.08%. In addition, the device's maximum light output power under 20-320mA driving current is 111.9mW, and the maximum photoelectric conversion efficiency is 27.12%. Figure 3 , 4 shown.

[0066] Comparative Examples 1-5, the chemical formula of the red-near infrared phosphor is: Mg(Ga 1-x Cr x )2O4, x are 0.0025, 0.005, 0.01, 0.02 and 0.03 respectively, and are prepared by a two-step synthesis method.

[0067] Comparative Example 1, x = 0.01

[0068] The difference between this comparative example and Example 1 is that the synthesis method is different, and a two-step synthesis method is adopted. The specific synthesis steps are as follows:

[0069] In the first step, the raw materials containing element A and element B (MgO, Ga2O3) and the raw materials containing Cr (Cr2O3) are fully ground, and a flux (H3BO3) is added. The first calcination is carried out in air. The operating conditions include: heating to 176°C at 4°C / min, keeping warm for 2 hours, then heating to 900°C at 4°C / min, keeping warm for 2 hours, then cooling to 350°C at 4°C / min, turning off the power, and cooling to room temperature (25-30°C) with the furnace.

[0070] In the second step, the product is fully ground and then calcined for the second time. The operating conditions of the second calcination include: heating to 900°C at 4°C / min, keeping warm for 1 hour, then heating to 1300°C at 4°C / min, keeping warm for 7 hours, then cooling to 900°C at 4°C / min, keeping warm for 1 hour, then cooling to 350°C at 4°C / min, turning off the power, cooling to room temperature (25-30°C) with the furnace, and crushing, grinding, washing, filtering and drying to obtain the red-near infrared phosphor.

[0071] Figure 5 , 6 The phosphor Mg(Ga was prepared by two-step synthesis. 1-x Cr x )2O4(x=0.0025、0.005、0.01、0.02、0.03) emission and excitation spectra, comparing the same phosphors obtained by the three-step synthesis method, the luminescence intensity of the phosphors obtained under the two synthesis conditions was integrated by area, and the integration results are shown in Figure 7 As shown, it can be seen that when other conditions are the same, the phosphor prepared by the three-step synthesis method has a larger overall integrated area and is more suitable for photobiomodulation applications.

[0072] Comparative Example 6

[0073] This comparative example provides a red-near infrared LED device. The difference between this comparative example and comparative example 1 is that the chemical formula of the red-near infrared phosphor is: Ca(Sc 0.99 Cr 0.01 )2O4, using a two-step synthesis method, calcination environment is N2, kept at 1500℃ for 6h, no flux is added, its emission spectrum and excitation spectrum are as follows Figure 8 , 9 shown.

[0074] The specific synthesis steps are:

[0075] In the first step, the raw materials containing element A and element B (CaCO3, Sc2O3) and the raw material containing Cr (Cr2O3) are fully ground and the first calcination is carried out. The operating conditions include: heating to 176°C at 4°C / min in a N2 environment, keeping warm for 2 hours, then heating to 900°C at 4°C / min, keeping warm for 2 hours, then cooling to 350°C at 4°C / min, turning off the power, and cooling to room temperature (25-30°C) with the furnace.

[0076] In the second step, the product is fully ground and then calcined for the second time. The operating conditions of the second calcination include: heating to 900°C at 4°C / min in a N2 environment, keeping warm for 1 hour, then heating to 1500°C at 4°C / min, keeping warm for 6 hours, then cooling to 900°C at 4°C / min, keeping warm for 1 hour, then cooling to 350°C at 4°C / min, turning off the power, cooling to room temperature (25-30°C) with the furnace, and crushing, grinding, washing, filtering and drying to obtain the red-near infrared phosphor.

[0077] Comparative Example 7

[0078] This comparative example provides a red-near infrared LED device. The difference between this comparative example and comparative example 6 is that the chemical formula of the red-near infrared phosphor is: Sr(Sc 0.99 Cr 0.01 )2O4, its emission spectrum and excitation spectrum are as follows Figure 8 , 9 shown.

[0079] The synthesis steps of the phosphor in this comparative example are the same as those of comparative example 6.

[0080] Comparative Examples 8-12

[0081] Comparative Examples 8-12 provide a Mg(Ga 0.99 Cr 0.01 )2O4 phosphor preparation method, the difference between comparative examples 8-12 and comparative example 1 is that: a two-step synthesis method is adopted, the second temperature increase in the second calcination is to 1100°C, 1200°C, 1300°C, 1400°C and 1500°C respectively, the insulation time is 6h, and no flux is added.

[0082] The emission spectra and excitation spectra of the red-near infrared phosphors of Comparative Examples 8-12 are as follows: Fig.10 , 11 shown.

[0083] Comparative Examples 13-16

[0084] Comparative Examples 13-16 provide a Mg(Ga 0.99 Cr 0.01 ) Preparation method of 2O4 phosphor, the difference between comparative examples 13-16 and comparative example 1 is that: a two-step synthesis method is adopted, and the holding time after the second heating to 1300°C in the second calcination is 4, 5, 7, and 8 hours respectively, and no flux is added.

[0085] The emission spectra and excitation spectra of the red-near infrared phosphors of Comparative Examples 13-16 are as follows: Fig.12 , 13 shown.

[0086] Comparative Examples 17-20

[0087] Comparative Examples 17-20 provide a Mg(Ga 0.99 Cr 0.01 )2O4 phosphor preparation method, the difference between comparative examples 17-20 and comparative example 1 is that: a two-step synthesis method is adopted, and during the second calcination process, the temperature is kept at 1300°C for 7 hours and different types of flux are added, namely aluminum fluoride, barium fluoride, ammonium fluoride, and no flux is used.

[0088] The emission spectra and excitation spectra of the red-near infrared phosphors of Comparative Examples 17-20 are as follows: Fig.14 , 15 shown.

[0089] Test Case

[0090] This test example uses the red-near infrared LED device Mg(Ga 0.98 Cr 0.02 )2O4 was used for the light irradiation experiment of lactic acid bacteria. The lactic acid bacteria were cultured in a 37℃ constant temperature incubator in the dark for 24 hours. The bacterial concentration in the solid culture medium was controlled in the countable range (30-300 cfu / ml). The lactic acid bacteria in the culture medium were exposed to 20mW / cm 2 Light dose, irradiation density is 1.5J / cm 2 The irradiation was carried out in a pulsed manner, 3 times a day, with each irradiation of 0.5 J / cm 2 , the colonies in each culture medium were counted or compared 2 hours after the last illumination. Figure 16 (a)-(b) shows the culture medium after 24 hours of cultivation, (a) is dark culture without illumination, (b) is the culture medium using the red-near infrared LED device Mg(Ga 0.98 Cr 0.02 )2O4 for PBM, it can be clearly seen that the lactic acid bacteria after 720nm light grow in sheets. Due to the rapid and dense growth, it is impossible to count, but the macroscopic effect of the light source on its growth is confirmed. Combined with the mechanism of action of lactic acid bacteria in PD and AD, the red-near infrared LED device Mg(Ga 0.98 Cr 0.02 )2O4 and the emitted light can promote the growth of probiotics represented by lactic acid bacteria, thereby achieving the treatment of neurological diseases.

[0091] The embodiments of the present invention have been described above, and the above description is exemplary, not exhaustive, and is not limited to the disclosed embodiments. Many modifications and changes will be apparent to those skilled in the art without departing from the scope and spirit of the described embodiments.

Claims

1. A red light-near infrared light LED device, characterized in that: The LED device is prepared by mixing red-near infrared fluorescent powder and transparent silica gel, and optionally red fluorescent powder, and packaging them through a packaging process; The chemical formula of the red-near infrared phosphor is: 1-x Cr x )2O4, wherein A is at least one of Mg, Ca and Sr, B is Ga and / or Sc, 0 <x<0.10; The preparation method of the red-near infrared phosphor comprises the following steps: The first step: contain Cr 3+ The raw material and the raw material containing element B are ground and mixed evenly, and calcined for the first time to obtain the first step product; Step 2: Grind and mix the raw material containing element A, the product of the first step and a flux evenly, and perform a second calcination to obtain a product of the second step; Step 3: Grind the product of the second step and then calcine it for the third time, and then crush, grind, wash, filter and dry it to obtain the red-near infrared phosphor.

2. The red-near infrared LED device according to claim 1, wherein: The ratio of the amount of the red-near infrared fluorescent powder, the amount of the red fluorescent powder and the amount of the transparent silica gel is (1-3): (0-0.1): 1; The chemical formula of the red phosphor is (Ca, Sr)AlSiN3:Eu 2+ , or, M2Si5N8:Eu 2+ , wherein M is at least one of Sr, Ca, Ba and Mg.

3. The red-near infrared LED device according to claim 1, wherein: The packaging process comprises: degassing and degassing a mixture of red-near infrared fluorescent powder, transparent silica gel and optional red fluorescent powder, then titrating the mixture on a blue LED chip, and baking and curing the mixture to obtain the red-near infrared LED device.

4. The red-near infrared LED device according to claim 3, wherein: The peak emission wavelength of the blue light LED chip is 400-500nm.

5. The red-near infrared LED device according to claim 1, wherein: The chemical formula A(B 1-x Cr x The value of x in )2O4 is: 0.0025 <x<0.03。 6. The red-near infrared LED device according to claim 1, wherein: The operating conditions of the first calcination include: in air or N2, heating to 850-950°C at 3-10°C / min, keeping warm for 0.8-1.2 hours, then heating to 1400-1500°C at 3-8°C / min, keeping warm for 1-5 hours, then cooling to 850-950°C at 3-10°C / min, keeping warm for 0.5-2 hours, then cooling to 250-350°C at 3-10°C / min, turning off the power, and cooling to 25-30°C with the furnace; The operating conditions of the second calcination include: in air or N2, heating to 100-300°C at 3-10°C / min, keeping warm for 0.5-2 hours, then heating to 500-1000°C at 3-10°C / min, keeping warm for 0.5-3 hours, then cooling to 250-350°C at 3-10°C / min, turning off the power, and cooling to 25-30°C with the furnace; The operating conditions of the third calcination include: conducting in air or N2, heating to 850-950°C at 3-10°C / min, keeping warm for 1 hour, then heating to 1100-1500°C at 3-8°C / min, keeping warm for 2-12 hours, then cooling to 850-950°C at 3-10°C / min, keeping warm for 0.5-2 hours, then cooling to 250-350°C at 3-10°C / min, turning off the power, and cooling to 25-30°C with the furnace.

7. The red-near infrared LED device according to claim 1, wherein: The raw material containing element B is at least one of oxides, nitrates, oxalates and carbonates containing element B; The raw material containing element A is at least one of oxides, nitrates, oxalates and carbonates containing element A; The amount of the flux added is 1-2.5% of the total mass of the raw materials used to prepare the red-near infrared phosphor; The flux is at least one of aluminum fluoride, barium fluoride, ammonium chloride, ammonium fluoride, ammonium difluoride and boric acid.

8. The red-near infrared LED device according to claim 7, wherein: The flux is boric acid.

9. The red-near infrared LED device according to any one of claims 1 to 8, wherein: The emission wavelength range of the red light-near infrared light LED device is 600-1050nm, and the emission wavelength peak is 700-730nm.

10. Use of the red-near infrared LED device according to any one of claims 1 to 9 as a light source for treating gastrointestinal diseases, neurological diseases and juvenile myopia.

Images