CN118767338A - LED packaging device with light homogenizing cavity and use method thereof - Google Patents

Abstract

The invention belongs to the field of medical instruments, and particularly discloses an LED packaging device with a light homogenizing cavity and a use method thereof. The device consists of a light homogenizing cavity, a light emitting diode and an air pressure regulating device. The light homogenizing cavity consists of a covering layer, a supporting piece and a bottom layer; the cover layer or/and the bottom layer are plastic film products. The air pressure adjusting device is communicated with the dodging cavity. The pressure difference between the cavity and the atmosphere is changed by air suction or inflation, so that the plastic film part in a loose state is deformed to form an inward concave or outward convex pneumatic optical element. The concave surface and the convex surface are off-axis paraboloids of revolution or conical-like surfaces. The cover layer is both a reflective surface of the light homogenizing cavity and a light output window. The light beam output by the LED array is reflected and diffused in the light homogenizing cavity and propagates along multiple paths. The output light spot forms approximately uniform light intensity distribution on the skin; thereby reducing the probability of ultraviolet damage to the DNA. The dead weight of the air pressure type hollow structure is small, and user comfort level is improved.

Description

LED packaging device with light homogenizing cavity and use method thereof

Technical Field

The present invention relates to the field of medical devices, and in particular to an LED packaging device with a light-homogenizing cavity and a use method thereof.

Background Art

Ultraviolet light therapy is a non-invasive, non-drug rehabilitation auxiliary treatment method.

Ultraviolet radiation can produce vitamin D precursors in the skin. This endogenous vitamin D helps the body absorb calcium and phosphorus, reducing the risk of osteoporotic fractures.

Irradiating the human body with ultraviolet radiation generated by light-emitting diodes can induce and produce a variety of hormones or peptides (including adrenocorticotropic hormone, melanocyte-stimulating hormone and endorphin). The above hormones and peptides have a positive effect on the prevention and treatment of non-skin autoimmune diseases.

However, when the illegal exposure leads to excessive doses, UV radiation has side effects. For example, DNA is the main target of UV radiation that directly or indirectly causes cell damage. UV radiation distorts the structure of DNA, introducing bends or kinks, thereby hindering transcription and replication. The harmful consequences of DNA damage include: cell death, mutations, skin photoaging, etc.

Therefore, reducing the probability of UV damage is a prerequisite for phototherapy to benefit patients.

Many LED ultraviolet light therapy research results (Light Emitting Diode, LED) have been publicly reported in this professional field. Among them, some research results have been made into prototypes (referred to as traditional wearable devices) and have produced significant therapeutic effects. However, the commercially available light therapy devices have shortcomings such as thick appearance and heavy weight on the human body:

Medical research results have shown that expanding the irradiation area is an effective measure to reduce the probability of ultraviolet damage. For traditional LED phototherapy devices, it is not difficult to expand the light-emitting area (just increase the cross-sectional area of the structure). The difficulty lies in that the structural parts of traditional wearable devices are made of medical silicone. If the cross-sectional area of the structure is increased, the amount of silicone will inevitably increase, resulting in an increase in weight. For example, a certain phototherapy device on the market is similar in size and weight to a tile (specifications 30*30cm^2). This means that the user is required to carry a tile weighing about 1.5kg, and a single treatment lasts about 30 minutes. The weight of this type of prototype is relatively large, and it is difficult to convince the elderly to continue to receive phototherapy happily throughout the winter.

In summary, although the irradiation area of traditional wearable devices is large and the safety is up to standard, they are heavy and have poor usability, which makes the overall performance not in line with the human factors engineering design concept of "people-oriented, safe, and pleasant".

Summary of the invention

The purpose of the present invention is to both expand the effective exposure area and reduce the weight of the whole machine.

In order to overcome the shortcomings of traditional technology, the present invention proposes the following technical measures: using lightweight plastic film to replace the heavy glass or/and silicone plate in traditional devices, designing a hollow structure, and using a flat closed space to produce a light homogenization function. Further, using the negative pressure difference (or positive pressure difference) of the air to "tighten and deform" the film preform to form a pneumatic light homogenization optical element with performance that meets industry standards, it produces a practical effect of a large treatment area, good safety performance, and light weight.

To achieve the above-mentioned object, the present invention provides an LED packaging device with a light-homogenizing cavity, comprising a covering layer, a supporting member, a bottom layer, a light-emitting diode and a gas pressure regulating device;

The support member is provided with a circular light-through hole or a square light-through hole with arc chamfers, and the two sides of the light-through hole of the support member are respectively connected to the cover layer and the bottom layer in an airtight manner to form a uniform light cavity, and the uniform light cavity contains a closed air gap;

The light homogenizing cavity is connected to the air pressure regulating device, and the air pressure regulating device regulates the air pressure in the light homogenizing cavity to a preset value;

The covering layer is a plastic film made of a material with a transmission/reflection beam splitting ratio of ≤1/2, and the inner surface reflectivity of the material is ≥60%. The covering layer is both a reflective surface of the light homogenizing cavity and a light output window of the LED packaging device;

The bottom layer is a plastic film or a hard thin plate, the inner surface of the bottom layer is covered with an aluminum reflective layer, the inner surface reflectivity is ≥ 60%, or it is provided with a sawtooth microstructure, or a microconvex or microconcave scattering structure;

When the pressure difference between the light homogenizing cavity and the environment is zero, the plastic film member is in a relaxed state;

When the pressure difference between the homogenizing cavity and the environment is less than zero, the atmospheric pressure causes the plastic film product to become concave, and the shape of the stretched plastic film product is an off-axis rotating parabola or a quasi-conical surface, or a cubic cone, resulting in a concave-plane structure, a concave-conical structure, or a concave-concave structure on both sides of the homogenizing cavity;

When the pressure difference between the homogenizing cavity and the environment is greater than zero, the atmospheric pressure causes the plastic film product to become convex, and the shape of the stretched plastic film product is an off-axis rotating parabola or a quasi-conical surface, or a cubic cone, resulting in a convex-plane structure, a convex-conical structure, or a convex-convex structure on both sides of the homogenizing cavity;

The light emitting diode is installed at the center or middle of the bottom layer; or the light emitting diode is installed on the inner wall of the light through hole of the support member; or a grid-shaped support frame is installed on the light through hole of the support member, the grid-shaped support frame is made of transparent material, and the light emitting diode is installed on the grid-shaped support frame;

The light from the light emitting diode is propagated along multi-path reflection and diffuse reflection in the light homogenizing cavity, producing a light homogenizing effect, and generating a light spot with an approximately uniform distribution of light power density on the outside of the covering layer; the effective irradiation area of the light spot is larger than the cross-sectional area of the transmitted light beam of a single light emitting diode directly irradiating the covering layer;.

Preferably, the air pressure regulating device comprises an air guide joint, an air guide tube, and a micro air pump; the air guide joint is arranged on the support member and is connected to the light homogenizing cavity; the micro air pump is connected to the air guide joint through the air guide tube.

Preferably, the air pressure regulating device also includes an air pressure sensor and an air pressure control module, the air pressure sensor is used to monitor the pressure difference between the homogenizing cavity and the external environment, and the air pressure control module controls the micro air pump to start exhaust, inflation, or stop according to the monitoring result of the air pressure sensor to maintain the air pressure in the homogenizing cavity at a preset value.

The pressure sensor is used to monitor the pressure difference between the homogenizing cavity and the atmosphere; the shape of the concave side of the homogenizing cavity is indirectly monitored through the pressure difference, and the shape parameter is the quantitative basis for the optical performance of the plastic film optical element. The pressure control module controls and adjusts or stabilizes the pressure difference; when the air pressure is normal, the LED driving power supply is turned on; when the air pressure is abnormal or the operating state is abnormal, the LED driving power supply is cut off.

Preferably, the covering layer is a film made of fluorine-containing polymer or polydimethylsiloxane material;

The support is made of non-transparent engineering plastic (strong ability to resist deformation under load and not easy to deform), with a thickness of not less than 1mm and a reflectivity of the inner surface of ≥60%;

Alternatively, the support member is made of quartz or polydimethylsiloxane material, and the transmittance is ≥ 60%.

Preferably, in the concave-plane structure, the light-emitting diode is installed at the center or middle of the bottom layer, and the bottom layer is a plastic or metal sheet with an aluminum reflective layer, the thickness of which is not less than 1 mm, and the inner surface reflectivity is ≥ 60%;

When the pressure difference between the airtight homogenizing cavity and the environment is less than zero, the shape of the cover layer is an off-axis rotating parabola, and the inner surface of the bottom layer is approximately a plane. At least four light-emitting diodes emit light in the homogenizing cavity, generating a light spot with approximately uniform light intensity distribution outside the cover layer.

Preferably, in the concave-conical structure, the light-emitting diodes are evenly mounted on the inner wall of the support, and the number of the light-emitting diodes is ≥4;

The bottom layer is a plastic or metal sheet with an aluminum reflective layer, the thickness of which is not less than 1 mm, and the inner surface reflectivity is ≥ 60%;

When the pressure difference between the homogenizing cavity and the environment is less than zero, the shape of the covering layer is approximately a quasi-conical surface or a square cone surface; the inner surface shape of the bottom layer is a quasi-conical surface or a square cone surface, and the inner surface of the bottom layer is a sawtooth microstructure.

Preferably, in the concave-concave structure, the light-emitting diodes are evenly mounted on the inner wall of the support, and the number of the light-emitting diodes is ≥4;

The bottom layer is a plastic film with an aluminum reflective layer, and the material reflectivity is ≥60%; the inner surface of the bottom layer is provided with a micro-convex or micro-concave scattering structure;

When the pressure difference between the light homogenizing cavity and the environment is less than zero, the shapes of the cover layer and the bottom layer are both off-axis rotation paraboloids; the axes of the rotation paraboloids of the cover layer and the bottom layer are approximately coincident.

Under the condition that the pressure difference between the homogenizing cavity and the environment is greater than zero and less than the rupture threshold of the thin film material, the shapes of the cover layer and the bottom layer are both off-axis rotation paraboloids; the axes of the cover layer and the bottom layer are approximately coincident;

Preferably, in the convex-convex structure, the light-emitting diodes are evenly mounted on the inner wall of the light-through hole of the support member; or the light-emitting diodes are evenly mounted on the grid-shaped support frame, and the number of the light-emitting diodes is ≥4;

The bottom layer is a plastic film with an aluminum reflective layer, and the material reflectivity is ≥60%; the inner surface of the bottom layer is provided with a micro-convex or micro-concave scattering structure;

Under the condition that the pressure difference between the homogenizing cavity and the environment is greater than zero and less than the rupture threshold of the thin film material, the shape of the covering layer and the convex shape of the bottom layer are similar to an off-axis rotating parabola; the axis of the covering layer and the parabola-like axis of the bottom layer approximately coincide.

Preferably, N of the LED package devices are assembled into a large-area phototherapy device using flexible connectors, and N≥4.

Preferably, the LED packaging device further comprises a photoelectric control module, a communication module, a security management module and a solid-state memory;

The photoelectric control module includes a signal acquisition and processing circuit, a microprocessor and software; each subsystem is operated by manual control or voice control and semantic recognition software; the operation method is prompted by a voice chip, including issuing a safety warning;

The communication module receives remote control instructions issued by an external control device or uploads data luminous state parameters, monitoring signals, etc. of the device by wireless communication;

The safety management module uses a tactile sensor and a micro switch to ensure that the LED package device is in close contact with the user's skin before the light emitting diode driving power is turned on;

The solid-state memory records the power-on time and photoelectric operating parameters, providing a basis for tracing back previous exposure doses.

Based on a general inventive concept, the present invention also provides a method for using an LED package device, wherein the LED package device with a uniform light cavity is used to deliver light energy to a user's skin area to be irradiated under the premise of strictly controlling the light dose.

The light dose is equal to the product of the radiation source intensity of the ultraviolet LED package device and the radiation exposure time; the light source generates one or more wavelengths within the bandwidth of 293-310nm.

The ultraviolet LED package device is used to project light energy to the user's skin area to be irradiated, and a certain dose of light produces an immunomodulatory effect, which is used to assist in the treatment of non-skin autoimmune diseases; the light energy produces hormones or peptides, including adrenocorticotropic hormone, melanocyte stimulating hormone, or beta-endorphin; or, produces at least one cis-uronic acid or DNA pyrimidine dimer;

The light dose is equal to the product of the radiation source intensity of the ultraviolet LED package device and the radiation exposure time; the light source generates one or more wavelengths within a narrower 293-310nm bandwidth; the irradiated area is 1%-30% of the total skin area of the user;

Ultraviolet erythema refers specifically to a skin erythema reaction induced by medium-wave ultraviolet radiation (UVB). Minimum Malerythemal Dose (MED) refers to the ultraviolet exposure time or dose required to produce the weakest erythema visible to the naked eye. This measurement helps to understand the sensitivity of a specific individual's skin to the ultraviolet dose received.

The safety management measures of the present invention include: determining the skin type of the user, and providing the user with a light dose that complies with the photobiological safety specification through a light emitting diode driving current controller when the ultraviolet LED package device is close to the skin; the safety management module sets the upper limit of the projection dose for a specific user to be less than 1 unit of Minimal Malerythemal Dose (MED) according to the skin type measurement result;

The light emitting element generates narrowband UVB radiation, which irradiates the skin to produce vitamin D precursor; the wavelength of light emitted by the light emitting element is 293-310nm; the light dose of the narrowband UVB irradiating the skin is 1-50mJ/ ^cm2 ; the ultraviolet LED package device irradiates the skin area of about 1% to 80% of the human body surface area.

Materials for manufacturing UV LED packaging devices:

UV-transmitting materials refer to quartz, polydimethylsiloxane (abbreviated as PDMS), polytetrafluoroethylene (transmitting type) and other fluorinated polymers;

UV reflective materials refer to metal aluminum and polytetrafluoroethylene (reflective type);

Materials with UV transmission/reflection splitting ratio ≤ 1/2, including polytetrafluoroethylene (transmission/reflection type) and optical film materials; Polyethylene (PE) film: In the (200-300) nm range, the transmittance of 30μm PE film is generally less than 20%, except at 274, 208, 232 and 292nm, with peak values at 274 and 292nm of 70% and 100% respectively.

Other fluorinated polymers include fluorinated ethylene-propylene (EFEP), fluorinated ethylene-propylene (FEP), perfluoroalkoxy (PFA), tetrafluoroethylene-hexafluoropropylene vinylidene fluoride (THV), polytetrafluoroethylene (PTFE), polyvinylidene fluoride (PVDF), ethylene-tetrafluoroethylene (ETFE), etc.

The beneficial effects of the present invention are as follows:

One of the technical advances of the present invention is that the covering layer is made of plastic film and the pneumatic optical element produces a uniform light effect on the LED light beam. In contrast, the covering layer of the conventional device is made of silicone, which is thick and heavy, and there is no room for further reducing the weight of the device.

(1) The LED packaging device provided by the present invention uses a plastic film to replace the silicone structure in the traditional device, resulting in a reduction in the weight of the entire device and an increase in user comfort.

Compared with conventional devices of the same area, the new device is half as thick and one-third as heavy. The convex cover layer forms a body-adapting contact with the skin, which improves the comfort of wearing the device.

(2) The concave homogenizing cavity increases the effective irradiation area of the whole device, which means that the power density of the light spot is reduced and the safety is increased.

The concave homogenizing cavity expands the effective irradiation area of a single LED. Compared with a single LED element in a traditional device, the effective irradiation area of a single tube in the new device is 10 times that of the traditional device. This means that the power density is reduced to 1/10 (below the safety limit). Furthermore, the concave structure forms an air gap between the LED and the skin, eliminating the possibility of the LED element irradiating the skin at close range and reducing the risk of UV radiation damaging DNA.

BRIEF DESCRIPTION OF THE DRAWINGS

The following drawings explain the main points of the technical solution of the present invention. The components in the schematic diagrams are not necessarily drawn to scale.

FIG1 is a schematic diagram of the structure of the LED packaging device in Example 1; FIG1(a) shows that the pressure difference between the light-homogenizing cavity and the atmosphere is zero, and the cover layer 1 is in a relaxed state; FIG1(b) shows that the pressure difference between the light-homogenizing cavity and the atmosphere is less than zero, and the cover layer 1 is in a tight state;

FIG2 is a schematic diagram of the structure of the pneumatic concave-planar optical element in Example 2;

FIG2(a) is a top view of the overall structure of the LED package device; FIG2(b) is a cross-sectional view along the B-B direction; FIG2(c) is a cross-sectional view along the C-C direction;

FIG3(a) is a schematic diagram of the reflection path of light in the device, where the covering plastic film 11 is an off-axis rotating parabola; FIG3(b) is a mathematical expression of the off-axis parabola in a rectangular coordinate system;

FIG4 is a numerical simulation result of the LED light beam propagation process in the pneumatic concave-plane homogenizing cavity in Example 2; FIG4(a) is a tracing diagram of the LED light in the homogenizing cavity, where a single LED 4 is installed at the center of the bottom layer 3;

FIG4( b ) is a numerical simulation result of the two-dimensional light intensity distribution of the cover layer output window (grayscale image), and FIG4( c ) is a numerical simulation result of the two-dimensional light intensity distribution of the cover layer output window (contour line image);

FIG5 is a schematic diagram of the structure of an LED package device with a convex-convex surface in Example 3; FIG5(a) is a three-dimensional schematic diagram of a convex-convex light homogenizing cavity; FIG5(b) shows that the light homogenizing cavity is in an inflated state; FIG5(c) shows that the pressure difference between the light homogenizing cavity and the atmospheric environment is zero, and the plastic films on both sides are in a relaxed state;

FIG6 is a schematic diagram of the position of the LED array in the convex-convex homogenizing cavity in Example 3; FIG6(a) is a schematic diagram of the LED light emitting diode 4 installed on the grid 21, and FIG6(b) is a schematic diagram of the light propagation path in the double convex cavity;

FIG. 7 is a three-dimensional structure of a concave-plane optical element in Example 4 (parts exploded schematic diagram), where four LED elements are mounted on the inner wall of the support 2;

FIG8 is a comparison of the plastic film of the cover layer (1) in Example 4 before and after deformation: FIG8(a) shows that the atmospheric pressure difference is zero and the plastic film 11 of the cover layer is in a relaxed state, and FIG8(b) shows that the atmospheric pressure causes the cover layer (1) to be concave inward, and the shape of the bottom layer remains approximately unchanged, forming a concave-flat optical element;

FIG8(c) is a cross-sectional view along the B-B direction of FIG8(b), where eight LED components are mounted on the inner wall of the support member;

FIG9 is a schematic diagram of the reflection and propagation of light in the light homogenizing cavity along multiple paths in Example 4, FIG9(a) is a schematic diagram of light propagation in the cross section of the support member 2 (further illustrating the details of FIG8c), FIG9(b) is a cross-sectional view along the C-C direction of FIG9(a), and FIG9(c) is a cross-sectional view along the D-D direction;

FIG10 is a three-dimensional structure of a concave-concave optical element in Example 5 (parts exploded schematic diagram), in which an LED element is mounted on the inner wall of a support member;

FIG11 compares the two plastic films of the cover layer (1) and the bottom layer (3) before and after deformation: FIG11(a) shows that the atmospheric pressure difference is zero, and the two plastic films of the cover layer and the bottom layer are in a relaxed state.

Figure 11(b) shows that atmospheric pressure causes the cover layer and the bottom layer to be concave inward, forming a double concave optical element.

FIG11( c ) is a cross-sectional view along the B-B direction of FIG11( b ), in which eight LED components are mounted on the inner wall of the support member;

Figure 12 is a schematic diagram of a large-area phototherapy device in Example 6, Figure 12(a) is a schematic diagram of a phototherapy device (6) suitable for irradiating the back of a human body and an air pressure regulating device (5), and Figure 12(b) is an A-A cross-sectional view of the LED packaging device in Figure 12(a); in the schematic diagram of the concave-flat homogenizing cavity, two LED elements and two concave plastic film optical elements are shown.

Description of Figure Numbers

1-covering layer; 11-plastic film part;

2-support member; 21-grid-shaped support frame;

3-bottom layer; 32-zigzag microstructure;

4-light emitting diode; 40-LED light; 41-transmitted light; 42-reflected light; 43-secondary transmitted light; 44-secondary reflected light;

5-air pressure regulating device; 51-air guide joint; 52-air guide tube; 53-micro air pump; 54-air pressure sensor; 55-air pressure control module;

6- Phototherapy equipment;

7- Skin.

The above drawings briefly introduce the main points of the present invention. Obviously, the drawings are only some embodiments of the present invention, and those skilled in the art can obtain other drawings based on these drawings without creative work.

DETAILED DESCRIPTION

Example 1: Concave optical element made of plastic film

The present invention uses a light plastic film to manufacture an LED packaging device, replacing the heavy optical glass or/and silicone body in a traditional phototherapy device, resulting in a lighter weight of the entire device. Specifically, the present invention applies atmospheric pressure to the light plastic film to deform it, thereby forming a pneumatic concave (or/and convex) optical element with a light-homogenizing effect.

(I) Structure of airtight light homogenizing cavity and air pressure controller

As shown in Fig. 1, the LED package device includes six basic components: a cover layer 1, a support member 2, a bottom layer 3, a light-emitting diode 4, an air pressure regulating device 5, and a control circuit. The support member 2 is a circular ring or a square frame. In this embodiment, the support member 2 is preferably a circular ring, and the light hole is circular. The cover layer 1 and the bottom layer 3 are respectively connected airtightly on both sides to form a concave-plane uniform light cavity, and the cavity is a closed air gap.

The cover layer 1 is made of a thin layer of plastic, and the plastic film component 11 is made of a material with a transmission/reflection splitting ratio of ≤1/2. Specifically, the material with a transmission/reflection splitting ratio of ≤1/2 refers to a fluorine-containing polymer or a polydimethylsiloxane material. In this embodiment, the cover layer 1 is preferably made of polytetrafluoroethylene. In other embodiments, the cover layer 1 can also be made of other fluorine-containing polymers including: fluorinated ethylene-propylene (EFEP), fluorinated ethylene-propylene (FEP), perfluoroalkoxy (PFA), tetrafluoroethylene-hexafluoropropylene vinylidene fluoride (THV), polytetrafluoroethylene (PTFE), polyvinylidene fluoride (PVDF), ethylene-tetrafluoroethylene (ETFE), etc. The inner surface reflectivity of the cover layer 1 is ≥60%, and the cover layer 1 is both the reflection surface of the uniform light cavity and the light output window of the LED packaging device.

The bottom layer 3 is a hard thin plate, and the inner surface of the bottom layer 3 is covered with an aluminum reflective layer. The inner surface reflectivity of the bottom layer 3 is ≥ the inner surface reflectivity of the covering layer 1; specifically, in this embodiment, the inner surface reflectivity of the covering layer 1 is ≥60%, and its transmittance is ≤20%. The support member 2 is made of a hard material. In this embodiment, the hard material is preferably engineering plastic. Under load, engineering plastic has a strong ability to resist deformation and is not easy to deform. The thickness is not less than 1 mm, and the reflectivity of the inner surface is ≥60%.

The air pressure regulating device 5 is connected to the homogenizing cavity and is used to increase or decrease, or maintain the air pressure of the closed air gap in the homogenizing cavity. When the pressure difference between the homogenizing cavity and the environment is zero, the cover layer and the bottom layer are in a relaxed state; as shown in Figure 1(a). When the pressure difference between the homogenizing cavity and the environment is less than zero, in Figure 1(b), the atmospheric pressure causes the plastic film to deform and tighten, and the plastic film product 11 becomes a concave optical element. The shape of the plastic film product of the cover layer 1 after tightening is an off-axis rotation parabola, and the two sides of the homogenizing cavity form a concave-plane structure.

Specifically, the air pressure regulating device 5 includes an air guide joint 51, an air guide tube 52, and a micro air pump 53. The air guide joint 51 is arranged on the outside of the support 1 and is connected to the light homogenizing cavity. The micro air pump 53 is connected to the air guide joint 51 through the air guide tube 52. Preferably, a valve is arranged on the air guide tube 52, and the valve switch is used to control whether the light homogenizing cavity and the micro air pump are connected. The air pressure regulating device 5 also includes an air pressure sensor 54 and an air pressure control module 55. The air pressure sensor 54 is arranged in the light homogenizing cavity to monitor the pressure difference between the light homogenizing cavity and the external environment. Specifically, the air pressure sensor 54 can be arranged on the inner surface of the support 2 or the bottom layer 3, preferably on the inner surface of the support 2. The air pressure control module 55 is electrically connected to the air pressure sensor 54 and the micro air pump 53 respectively. The air pressure control module 55 controls the micro air pump 53 to start or stop air extraction according to the monitoring result of the air pressure sensor 54, so as to maintain the air pressure in the light homogenizing cavity at a preset value.

Referring to FIG. 2 and FIG. 4( a), the light emitting diode 4 is installed at the center of the bottom layer 3. The light of the light emitting diode 4 is propagated along multi-path reflection and diffuse reflection in the light homogenizing cavity, producing a light homogenizing effect, and generating a light spot with a light intensity approximately uniformly distributed on the outside of the cover layer 1. The concave (or convex) surface of the light homogenizing cavity expands the effective irradiation area of the light spot (the actual irradiation area is larger than the cross-sectional area of the transmitted light beam of a single light emitting diode 4 directly irradiating the cover layer 1).

In this embodiment, the pressure sensor 54 is used to monitor the pressure difference between the light homogenizing cavity and the atmosphere; the shape of the concave side of the light homogenizing cavity is indirectly monitored through the pressure difference, and the shape parameter is a quantitative basis for the optical performance of the air pressure type optical element made of a thin layer of plastic. The air pressure control module 55 controls and adjusts or stabilizes the pressure difference; under normal air pressure conditions, the driving power supply of the light emitting diode 4 is turned on; when the air pressure is abnormal or the operating state is abnormal, the driving power supply of the light emitting diode 4 is cut off.

(ii) Using the air pressure difference driving principle to strengthen the shape of the concave plastic film

The core content of the present invention is to use the concave (or convex) plastic film member of the cover layer 1 as a reflection/transmission surface to form a pneumatic optical element, which has a uniform light effect on the LED light beam.

However, for conventional, solid optical elements, without reinforcement measures, the concave plastic film of the cover layer 1 has the potential disadvantage of being unstable in shape. For this reason, common practical optical elements avoid using flexible plastic films (the optical instrument industry tends to use hard materials to make reflective/transmissive optical elements).

In view of the shortcoming of "unstable shape of flexible film devices", the present invention designs the concave plastic film parts into pneumatic components, which has the beneficial effect of not only reducing the weight of the whole machine by using the plastic film parts, but also eliminating the shortcoming of unstable shape of the flexible film.

The pneumatic components operate as follows:

When the phototherapy device is turned on, the air pressure control module 55 controls the micro air pump 53 to start air extraction, and the pressure in the sealed light homogenizing cavity drops, and the atmospheric pressure tightens the plastic film of the cover layer 1. The atmospheric pressure difference produces the actual effect of "configuration reinforcement", so that the tightening of the cover layer 1 forms a stable off-axis rotating parabola shape (as shown in Figures 1b and 3a), so that the light homogenizing effect of the concave plastic film of the cover layer 1 is no different from that of a hard optical lens.

(iii) The concave plastic film of the present invention has a stable configuration.

In Figure 1(b), when the pressure difference between the homogenizing cavity and the environment is less than zero, the negative pressure difference is defined as:

( _{Phomogeneous cavity} -P _atmosphere ) < 0,

Where, the atmospheric pressure is _Patmosphere and the absolute pressure of the homogenizing cavity is _{Phomogenizing cavity} .

The calculation method for the stress analysis of plastic film is as follows:

Known conditions 1: 1 atmospheric pressure P _atmosphere ≌ 1.03325 kgf/cm ² (unit: kgf/cm ² );

Known condition 2: the area S of the covering layer 1 in Figure 1 _{is plastic film} ≌ 100 cm ² ;

A small amount of air is extracted from the homogenizing cavity, and the pressure difference between the atmosphere and the homogenizing cavity is about 1/100 of the atmospheric pressure. That is,

Pressure difference: (P _atmosphere - P _{homogenizing cavity} )/P _atmosphere ≌ 1/100,

Air pressure F: F _{air pressure} = (P _atmosphere - P _{homogenizing cavity} ) * S _{plastic film} ≌ 1 kgf. (Formula 1)

Force calculation results: The atmospheric pressure borne by the plastic film of the covering layer 1 is about 1 kgf (engineering kilogram force).

On the one hand, this pressure is enough to drive the plastic film of the covering layer 1 into a conical concave surface (as shown in Figure 1b and Figure 2). On the other hand, the force-bearing area S _{of the plastic film} is large, but the force per unit area is not large. The output film withstands a pressure of 1kgf (engineering kilogram force) without causing the material to break. The area of the plastic film of the covering layer 1 can be selected in different sizes according to actual conditions. Even if the area of the plastic film of the covering layer 1 is increased to more than ^1000cm2 , it can still withstand the atmospheric pressure caused by the pressure difference.

Repeatability of the plastic film shape of this device :

Operating condition 1: Temperature is one of the factors that affect the stability of the device, but the range of variation is not large. For example, the temperature gauge is clamped in the armpit and the reading is taken after 10 minutes, and the average value is 36-37°C. It can be inferred that during the phototherapy process, the operating temperature of the device varies by about 1°C.

Operation condition 2: Each treatment lasts no longer than 30 minutes.

The design goal of the present invention is to keep the plastic film of the cover layer 1 at its concave size. The curvature radius of the concave plastic film is defined as a spherical surface with a radius r, and our design index is to keep the curvature radius 1/r constant.

According to the Young–Laplace law, the law of the change of the spherical shape of the balloon is:

The rule expressed by Formula 2 is that the radius of curvature r of the concave surface is inversely proportional to the pressure difference ΔP and is directly proportional to the tension coefficient of the plastic material.

In this embodiment, the plastic film of the covering layer 1 is a polytetrafluoroethylene film. Under the condition that the human body temperature remains stable within 30 minutes, the tension coefficient σ(r) of the plastic is approximately equal to a constant.

The device uses an air pressure sensor 54 to monitor the change in the pressure P of _{the homogenizing cavity} , and uses a micro _air pump 53 to control the pressure value so that P maintains a stable value; thereby making the concave curvature 1/r approximately a constant.

In summary, under the background that the pressure P _{of the homogenizing cavity} is kept constant, the shape of the concave surface of the plastic film of the cover layer 1 of the present invention is repeatable and has good optical reflection/transmission performance in the homogenizing cavity.

The atmospheric pressure is limited to causing a repeatable change in the shape of the plastic film, but will not cause the diaphragm to rupture, making the pneumatic component safe for operation.

Example 2: Concave-plane uniform light structure, with a single LED located at the center of the bottom layer

Fig. 2 is a schematic diagram of the structure of an LED package device. Its technical characteristics are that the geometric profile of the core component cover layer 1 is an off-axis rotation parabola, and the light emitting diode 4 is installed at the center of the bottom plane.

The middle of the support 2 is a circular light hole, the cover layer 1 is pasted on one side close to the skin 7, and the bottom layer 3 is pasted on the other side; the support 2 is made of engineering plastic (under load, it has strong ability to resist deformation and is not easy to deform), its thickness is not less than 1mm, and the reflectivity of the inner surface is ≥60%; or it is made of quartz or polydimethylsiloxane material, and its transmittance is ≥60%, and there is an air guide joint 51 on the support 2;

The bottom layer 3 is a plastic or metal sheet with an aluminum reflective layer, the thickness of which is not less than 1 mm, and the inner surface of the bottom layer has an approximately flat shape, and the reflectivity is ≥ 60%; in the cross-sectional views B-B and C-C of Figure 2, the shape of the thin plate material of the bottom layer 3 is square, but only the central circular light-through hole area has a reflective effect on light.

Under the condition that the pressure difference between the light homogenizing cavity and the environment is less than zero, the concave plastic film of the cover layer 1 is an off-axis rotation parabola, as shown in Figure 3(a). The cover layer 1, the bottom layer 3 and the inner wall of the support 2 form a concave-plane structure with light homogenizing function; in the rectangular coordinate system, the cross section of the cover layer 1 is an off-axis parabola as shown in Figure 3(b). That is, the geometric shape of the plastic film of the cover layer 1 is the parabola equation in the XOY coordinate system, y ² =2px, (p>0),

The coordinates of the vertex of the parabola are: x = -p/2, y = 0. The deflection angle of the XOY coordinate system relative to the laboratory X′OY′ coordinate system is

The following is a brief description of the propagation mode of LED light in the homogenizing cavity:

The LED light tracing diagram in the homogenizing cavity is shown in FIG4a . The top radius of the parabola is 1 cm, the focal length is 0.025 cm, the distance between the light emitting diode 4 and the top of the parabola is 0.06 cm, the light emitting surface of the light emitting diode 4 is 0.048 cm*0.048 cm, the power is 0.001 W, and the beam divergence angle is 120°.

As shown in Figure 4a, the LED element emits light at the center of the bottom layer, and a part of the light reaches the cover layer 1 and is divided into two parts: transmission and reflection. Among them, the reflected light is reflected along multiple paths or diffusely reflected between the cover layer 1, the bottom layer 3 and the support 2. When the other part of the light reaches the cover layer 1 again, it is divided into two parts again: transmission and reflection. Outside the cover layer 1, multiple beams of transmitted light are incoherently superimposed to produce a light spot with a nearly uniform light intensity distribution.

Figure 4 (b) and (c) are two-dimensional light intensity distribution diagrams of the output window of the cover layer 1. The numerical simulation results show that the illumination effect of a single LED is:

The diameter of the effective illumination range is about 11 cm. The light power at 5.5 cm from the center is 3 microwatts/cm ² . In the figure, the maximum LED power is 11.9 microwatts/cm ² .

Example 3 In the inflated state, the homogenizing cavity has a convex-convex structure

Under the pressure of the gas in the cavity, the cover layer and the bottom layer bulge outward at the same time, and the three-dimensional structure of the double convex phototherapy device is shown in Figure 5. The main difference from Example 2 is that the nature of the bottom layer material is different, the bottom layer 3 is a plastic film with an aluminum reflective layer, and the material reflectivity is ≥ 60%; the surface of the aluminum reflective layer is processed with a microstructure with scattering properties, specifically a micro-convex or micro-concave scattering structure;

The optical output surface (covering layer 1) and the reflecting surface (bottom layer 3) are parabolic/spherical surfaces modified by the "evening effect"; their performance characteristics are:

In the non-operating state, the plastic films on both sides of the device are in a relaxed state (as shown in FIG. 5 c ), and the device has a flat shape, a small thickness, and a light weight;

In the positive pressure difference state, the two surfaces are convex (as shown in FIGS. 5 a and 5 b ), and the LED emits light 40 directed toward the reflective surface of the bottom layer 3 ; then, the corresponding transmitted light 42 irradiates the skin 7 through the cover layer 1 ;

The phototherapy effective irradiation area of this device is large; it is suitable for phototherapy of the back of the human body.

The support member 2 is a light-weight flat plate, and the opening area of the circular light-through hole on the support member 2 is the effective output area; an optical output film (for example, a prefabricated fluorine-containing polymer film, or a polydimethylsiloxane film) is bonded to the right side of the circular light-through hole; a plastic film with a reflective layer (for example, a micro-convex and concave scattering structure is provided on an aluminum-plated plastic film) is bonded to the left side; the operation mode is as follows:

In the zero pressure difference state, both the optical output layer and the reflective layer are plastic films in a relaxed state, as shown in FIG5c.

A micro air pump 53 is used to inflate the light homogenizing cavity through the air guide joint 51 and the air guide tube 52 to generate a positive air pressure difference, thereby forming a "double convex" light homogenizing device, as shown in FIGS. 5a and 5b.

In FIG6 , a circular light hole (or a square light hole with four rounded corners) is provided in a rectangular (or square with curved chamfered corners) support member 2. A grid-like support frame 21 is installed in the hole. The grid-like support frame 21 is made of a transparent material. A plurality of (six in this example) light-emitting diodes 4 are installed on the grid-like support frame 21 to form an LED array.

In the light homogenizing device, the light emitted by the light emitting diode 4 is reflected (diffusely reflected) and transmitted along multiple paths; for example, a representative path for the propagation of a part of the light is: LED light 40 → reflected light 42 → transmitted light 41 → reaches the skin 7; a representative path for the multipath reflection propagation of a part of the reflected light (41) in the cavity is: LED reflected light 44 → reflected light... → transmitted light 41 → reaches the skin 7; as shown in Figure 6b.

In FIG. 6( b ), the LED initial light ( 40 ) is directed toward the bottom layer on the right side. In other words, the LED initial light is not directed directly toward the cover layer ( 1 ) on the left side. Therefore, there is no light path in the device for the initial light to directly reach the skin ( 7 ).

Embodiment 4 Concave-plane uniform light structure, LED is installed on the inner wall of the annular support

The three-dimensional structure of the LED package device is shown in FIG7 . The main structure is the same as that of the LED package device in Example 1. The main difference is that when the pressure difference between the light-homogenizing cavity and the external environment is less than zero, the concave plastic film of the cover layer 1 is a cone-like shape, and the eight light-emitting diodes 4 are evenly arranged on the inner wall of the support 2. The light beams of the light-emitting diodes 4 do not directly irradiate the skin 7 (as shown in FIG8 and FIG9 ). At the same time, a sawtooth microstructure 32 is provided on the surface of the inner surface of the aluminum reflective layer of the bottom layer 3 .

The pressure difference is defined as the difference between the atmospheric pressure and the absolute pressure in the light homogenizing cavity (a negative value is taken when the air is evacuated; Example 1 provides an example of the design calculation of the atmospheric pressure).

Figure 8 compares the changes of the plastic film of the cover layer 1 before and after deformation:

State I : In the zero pressure difference state, the cover layer 1 is a plastic film in a relaxed state, as shown in the cross-sectional view of the homogenizing cavity in FIG8 (a);

State II : The micro vacuum pump 53 extracts air from the light homogenizing cavity, and the atmospheric pressure makes the cover layer 1 become a concave optical element;

The "concave" cover layer 1 and the flat bottom plate 3 form a "concave-flat" optical element, as shown in Figure 8(b). Figure 8(c) is a cross-sectional view of the light homogenizing cavity A-A, where the air guide joint 51 is located on the support 2, see Figure 7 for details;

* Note 1: The deformation of the bottom layer 3 caused by the pressure difference is very small, and the bottom layer 3 is approximated as a flat plate.

At least four light-emitting diodes 4 are installed on the inner wall of the ring of the support member 2 to form an LED ring array; the main axis of the light beam of the light-emitting diode 4 is perpendicular to the center axis of the ring; in Figure 8, preferably eight light-emitting diodes 4 are evenly arranged along the circumference of the inner wall of the support member 2.

The present invention adopts the following four technical measures to improve the uniformity of the output light spot, as shown in FIG9 :

Measure I : Use materials with a "transmission/reflection splitting ratio ≤ 1/2" to generate a large amount of reflected light.

The covering layer 1 is made of a material with adjustable transmission/reflection splitting ratio, so that the LED light is divided into two parts on the surface of the covering layer 1; wherein the transmitted light 41 reaches the treatment object, and the reflected light 42 propagates in multiple paths in the wedge-shaped medium.

* Note 2: For example, in this embodiment, the beam splitting ratio of the prefabricated polytetrafluoroethylene film is: partial transmittance ≤ 20%, partial reflectivity ≥ 60%.

Measure II : In the wedge-shaped air gap, light is reflected/diffusely reflected and transmitted along multiple paths, producing a uniform light effect.

Air is a low-loss propagation medium for ultraviolet light. As shown in Figures 9b and 9c, a "wedge-shaped" air gap is formed between the cover layer 1 and the bottom layer 3. In the wedge-shaped medium, the LED light propagates along a typical Z-shaped path. The LED light 40 is transmitted through the cover layer 1 to form a transmitted light 41, which directly reaches the skin 7; the reflected light 42 continues to propagate along the Z-shaped path in the homogenizing cavity, and then forms a secondary transmitted light 43.

The sawtooth microstructure 32 disposed on the surface of the bottom layer 3 produces a further light homogenization effect.

*Explanation 3: The multipath reflection/transmission process in the wedge-shaped air gap of the present invention can be compared to the multipath reflection/transmission process in a solid gap (wedge-shaped quartz light guide plate).

Measure III : Using ray tracing method, the deformation of the output layer (plastic film product 11) under air pressure is simulated and the "light uniformity effect" is corrected; in this embodiment, when the cover layer 1 is tightened, a conical concave surface or a square pyramid concave surface (mathematically corrected surface) is formed.

Measure IV : By changing the driving current of the LED matrix rows and columns, the uniformity of the light emission of the LED array rows and columns is fine-tuned to form a light spot with a nearly uniform light intensity distribution near the skin 7.

The phototherapy device provided in this embodiment has a flat appearance, a small thickness (in a negative pressure difference state, the surface is concave), a large effective irradiation area, and a light weight; it is suitable for phototherapy of the human back.

Example 5 Concave-concave light homogenization structure, LED is installed on the inner wall of the annular support

The three-dimensional structure of the double concave LED packaging device of this embodiment is shown in Figure 10. The main difference from the concave-plane structure of Example 4 is that: the properties of the bottom layer 3 are different. The bottom layer 3 is a plastic film with an aluminum reflective layer, and the material reflectivity is ≥60%; the surface of the aluminum reflective layer is processed with a microstructure with scattering properties, specifically a micro-convex or micro-concave scattering structure; under the condition that the pressure difference between the homogenizing cavity and the environment is less than zero, the shapes of the cover layer 1 and the bottom layer 3 are both inwardly concave off-axis rotation paraboloids.

The cover layer 1 is a prefabricated fluorine-containing polymer film, and in other embodiments it may also be a polydimethylsiloxane film; the bottom layer 3 is a plastic film with an aluminum reflective layer, and a micro-convex or micro-concave scattering structure is arranged on the aluminum reflective layer.

FIG11 compares the changes in the homogenizing cavity structure before and after deformation of the plastic film of the cover layer 1 and the plastic film of the bottom layer 3;

In the zero pressure difference state, the cover layer 1 and the bottom layer 3 are both plastic films in a relaxed state, as shown in FIG11( a );

In the negative pressure difference state, the ambient atmospheric pressure causes the plastic films of the cover layer 1 and the bottom layer 3 to be concave, forming two off-axis rotation paraboloids.

Figure 11(b) is the A-A cross-sectional view of the homogenizing cavity; the pressure difference between the homogenizing cavity and the atmosphere is less than zero, and the atmospheric pressure deforms the plastic film, and the cover layer and the bottom layer become double concave optical elements.

Compared with Embodiment 2 and Embodiment 4, the biconcave plastic film of this embodiment minimizes the total weight of the light homogenizing structure. The light homogenizing cavity has a stronger light homogenizing function, generating a light spot with a light intensity approximately uniformly distributed outside the cover layer 1 .

Example 6: Operating a phototherapy device in close proximity to the human body

Medical research results show that the larger the irradiation area of ultraviolet light therapy, the better the effect of inducing the synthesis of vitamin D precursors in the skin. At the same time, the ultraviolet dose required to produce photochemical reactions is reduced, and the probability of ultraviolet radiation damaging DNA decreases accordingly.

The present invention uses a flexible connector to assemble N LED package devices into a large-area phototherapy device 6, where N≥4; as shown in FIG. 12 , the back-specific phototherapy device provided by the present invention can cover approximately 9% of the area of human skin.

When used close to the back of the human body, the negative pressure difference causes the cover layer 1 to have a concave surface, forming a ventilation and perspiration interval between the skin, which can improve the user's physical comfort.

A light ring is used as the support 2, and the light hole area of the support 2 is the effective treatment area; the air guide connector 51 provided on the support 2 is connected to the micro air pump 53. The connection sequence of the air path is: the airtight space of the homogenizing cavity → the air guide connector 51 → the air guide tube 52 → the micro air pump 53.

The air pressure control module 55 is electrically connected to the micro air pump 53; the air pressure sensor 54 is used to monitor the pressure difference between the light homogenizing cavity and the atmosphere; the air pressure control module 55 controls, adjusts or stabilizes the pressure difference;

The shape change of the concave side of the homogenizing cavity is inferred through the indirect measurement value of the pressure difference. The shape change parameter is the quantitative basis for evaluating the optical performance of the plastic film optical element. When the air pressure is normal, the LED driving power is turned on; when the air pressure is abnormal or the operating state is abnormal, the LED driving power is cut off.

FIG12(b) is a cross-sectional view of the LED package device along line A-A; in the schematic diagram of the concave-plane homogenizing cavity, two LED components and two concave plastic film optical components are shown. When the phototherapy device is turned on, the micro vacuum pump 53 pumps air to generate a negative pressure difference in the homogenizing cavity, causing the cover layer 1 (or the bottom layer 3) of the homogenizing cavity to "deform" into a concave optical component. Between the cover layer 1 and the bottom layer 3, the light of the light emitting diode 4 propagates along the multi-path reflection, diffuse reflection/transmission light path, and produces the effect of homogenizing the spatial distribution of light intensity (see FIG4 and FIG9 for details).

Note: It is known to those skilled in the art that plastic film optical elements have the inherent disadvantage of "large aberration". "Aberration" means that the point spread function is degraded (i.e., the energy is dispersed into a larger spatial domain), which is a harmful factor for imaging optical systems.

It should be pointed out that the phototherapy device is a non-imaging optical system, and the "light energy dispersion phenomenon" is not a disadvantage, but a favorable factor for improving the uniformity of the phototherapy spot.

The light homogenization measure adopted by the present invention is that the LED light is propagated along multi-path reflection and diffuse reflection in the light homogenization cavity, which produces a light homogenization effect on the output light spot, and the aberration enhances the "light homogenization" so that the light spot intensity distribution curve tends to be flat.

The present invention utilizes atmospheric pressure to "reinforce" the shape of plastic film optical elements.

Plastic film is soft and easily deformed, which is an inherent disadvantage of plastic film. In principle, it cannot be used as an independent optical element.

Installing the plastic film in the evacuated (or de-evacuated) state in the airtight cavity is one of the core technologies of the present invention, which effectively avoids the disadvantage of "the plastic film is easy to deform".

Specifically, the present invention uses atmospheric pressure to keep the plastic film in a taut state, which is equivalent to "solidifying" the shape of the plastic film. In the new light homogenizing cavity, the shape of the plastic film optical element has good repeatability, producing a good light homogenizing effect.

The present invention adopts the above-mentioned multiple measures to improve the uniformity of the output light spot, which produces the substantial effect of not only improving the efficiency of synthesizing vitamin D in the body, but also minimizing the dose of ultraviolet radiation projected into the body, thereby minimizing the probability of ultraviolet radiation damaging health.

Example 7 Method of using a phototherapy device

Ultraviolet light therapy has auxiliary therapeutic effects on non-skin autoimmune diseases. The light energy produces hormones or peptides, including adrenocorticotropic hormone, melanocyte stimulating hormone, or beta-endorphin; or, produces at least one cis-uronic acid or DNA pyrimidine dimer; during light therapy, the light dose provided to the user is determined by a controller, and the light dose is defined as the product of the ultraviolet radiation source intensity of the LED package device and the exposure time of the ultraviolet radiation source, and the light dose is ≤3J/ ^cm2 ; the ultraviolet radiation source includes one or more target wavelengths within the bandwidth range of 280-320nm.

The safety management measures of the present invention include: determining the skin type of the user, and providing the user with a light dose that meets the photobiological safety specification by driving a current controller through a light emitting diode when the ultraviolet LED package device is close to the skin; the safety management module sets the upper limit of the projection dose for a specific user to be less than 1 unit of Minimal Erythemal Dose (MED) according to the skin type measurement result;

The ultraviolet erythema mentioned above refers specifically to a skin erythema reaction induced by medium-wave ultraviolet radiation (UVB). Minimum erythema dose (MED) refers to the ultraviolet irradiation time or dose required to produce the weakest erythema visible to the naked eye. This measurement value helps to understand the sensitivity of a specific individual's skin to the ultraviolet dose received.

As shown in FIG12 , the user's skin type is determined. When the LED package device is close to the user's skin, the light emitting diode 4 generates narrow-band UVB radiation to irradiate the skin to produce vitamin D precursor. The wavelength of the light emitting diode 4 is 297±20nm. The light dose of the narrow-band UVB irradiating the skin is 1-50mJ/cm ² . The area of the skin irradiated by the LED package device is 1% to 80% of the human body surface area.

The embodiments described above are only preferred specific implementation modes of the present invention, but the protection scope of the present invention is not limited thereto; any technician familiar with the technical field can make equivalent replacements or changes according to the technical solutions and concepts of the present invention within the technical scope of the present invention, which should be covered by the protection scope of the present invention.

Claims (10)

1. An LED packaging device with a light homogenizing cavity is characterized by comprising a covering layer (1), a supporting piece (2), a bottom layer (3), a light-emitting diode (4) and an air pressure regulating device (5);

the support piece (2) is provided with a round light-passing hole or a square light-passing hole with an arc chamfer, two sides of the light-passing hole of the support piece (2) are respectively and hermetically connected with the covering layer (1) and the bottom layer (3) to form a light-homogenizing cavity, and a closed air gap is formed in the light-homogenizing cavity;

the light homogenizing cavity is communicated with the air pressure adjusting device (5), and the air pressure adjusting device (5) adjusts the air pressure in the light homogenizing cavity to be at a preset value;

The cover layer (1) is a plastic film product, the reflectivity of the inner surface of the plastic film is more than or equal to 60%, and the cover layer (1) is a reflecting surface of the light homogenizing cavity and is a light output window of the LED packaging device;

The bottom layer (3) is a plastic film product or a hard sheet, the inner surface of the bottom layer (3) is covered with an aluminum reflecting layer, and the reflectivity of the inner surface is more than or equal to 60 percent, or a zigzag microstructure, a slightly convex or slightly concave scattering structure is attached to the inner surface;

When the pressure difference between the dodging cavity and the atmospheric environment is zero, the plastic film part is in a loose state;

When the pressure difference between the light homogenizing cavity and the atmospheric environment is smaller than zero, the atmospheric pressure enables the plastic film workpiece to become concave, and the shape of the stretched plastic film workpiece is an off-axis rotary paraboloid or a similar conical surface or a cubic conical surface, so that a concave-plane structure or a concave-conical surface structure or a concave-concave surface structure is formed on two sides of the light homogenizing cavity;

when the pressure difference between the light homogenizing cavity and the atmospheric environment is greater than zero, the plastic film workpiece is enabled to be convex by gas pressure, the shape of the stretched plastic film workpiece is an off-axis rotating paraboloid or a conical surface or a cubic conical surface, and a convex-plane structure or a convex-conical surface structure or a convex-convex surface structure is formed on two sides of the light homogenizing cavity;

The light emitting diode (4) is arranged in the middle of the bottom layer (3); or the light emitting diode (4) is arranged on the inner wall of the light passing hole of the supporting piece (2); or a grid-shaped supporting frame (21) is arranged in the light transmission hole of the supporting piece (2), the grid-shaped supporting frame (21) is made of transparent material, and the light emitting diode (4) is arranged on the grid-shaped supporting frame (21);

Light rays emitted by the light emitting diode (4) are reflected and spread along multiple paths in the light homogenizing cavity to generate a light homogenizing effect, and light spots with approximately uniform optical power density are generated outside the covering layer (1); the effective irradiation area of the light spot is larger than the cross-sectional area of a transmitted light beam of which the single light emitting diode (4) directly irradiates the covering layer (1).

2. The LED package device with the light homogenizing cavity according to claim 1, characterized in that the air pressure adjusting means (5) comprises an air guide joint (51), an air guide pipe (52) and a micro air pump (53), the air guide joint (51) is arranged on the support (2) and is communicated with the light homogenizing cavity, and the micro air pump (53) is communicated with the air guide joint (51) through the air guide pipe (52).

3. The LED package device with the dodging cavity according to claim 2, wherein the air pressure adjusting device (5) further comprises an air pressure sensor (54) and an air pressure control module (55), the air pressure sensor (54) is used for monitoring the pressure difference between the dodging cavity and the atmosphere, and the air pressure control module (55) controls the micro air pump (53) to start air suction, air inflation or stop according to the monitoring result of the air pressure sensor (54) so as to maintain the air pressure in the dodging cavity at a preset value.

4. LED package device with a light homogenizing cavity according to claim 1, characterized in that the cover layer (1) is a thin film of a fluoropolymer or polydimethylsiloxane material;

The supporting piece (2) is made of hard non-transparent materials, the thickness is not less than 1mm, and the reflectivity of the inner surface is more than or equal to 60%;

or the supporting piece (2) is made of quartz or polydimethylsiloxane material, and the transmissivity is more than or equal to 60 percent.

5. The LED package device with the light homogenizing cavity according to claim 1, characterized in that in the concave-planar structure, the light emitting diode (4) is mounted at the center of the bottom layer (3), the bottom layer (3) is a plastic or metal sheet with an aluminum reflective layer, the thickness is not less than 1mm, and the internal surface reflectivity is not less than 60%;

When the pressure difference between the dodging cavity and the atmospheric environment is smaller than zero, the shape of the covering layer (1) is an inward concave off-axis rotating paraboloid, and the inner surface of the bottom layer (3) is approximately a plane.

6. The LED package device with a light homogenizing cavity according to claim 1, characterized in that in the concave-cone structure, the light emitting diodes (4) are uniformly mounted on the inner wall of the support (2), the number of the light emitting diodes (4) being equal to or larger than 4;

the bottom layer (1) is a plastic or metal sheet with an aluminum reflecting layer, the thickness of the bottom layer is not less than 1mm, and the reflectivity of the inner surface is more than or equal to 60%;

When the pressure difference between the dodging cavity and the atmospheric environment is smaller than zero, the shape of the covering layer (1) is similar to a conical surface or a cubic conical surface; the inner surface of the bottom layer (3) is shaped like a conical surface or a cubic conical surface, and the inner surface of the bottom layer (3) is provided with a zigzag microstructure.

7. The LED package device with a light homogenizing cavity according to claim 1, characterized in that in the concave-concave structure, the light emitting diodes (4) are uniformly mounted on the inner wall of the support (2), the number of the light emitting diodes (4) being equal to or larger than 4;

The bottom layer (1) is a plastic film with an aluminum reflecting layer, and the reflectivity of the material is more than or equal to 60%; the inner surface of the bottom layer (1) is provided with a slightly convex or slightly concave scattering structure;

When the pressure difference between the dodging cavity and the atmospheric environment is smaller than zero, the concave surfaces of the cover layer (1) and the bottom layer (3) are off-axis rotary paraboloids; the axis of the cover layer (1) approximately coincides with the paraboloid axis of the bottom layer (3).

8. The LED package device with a light homogenizing cavity according to claim 1, characterized in that in the convex-convex structure the light emitting diodes (4) are uniformly mounted on the inner wall of the light passing hole of the support (2); or the light emitting diodes (4) are uniformly arranged on the grid-shaped supporting frame (21);

The number of the light emitting diodes (4) is more than or equal to 4;

under the condition that the pressure difference between the dodging cavity and the atmospheric environment is larger than zero and smaller than the rupture threshold value of the film material, the shape of the cover layer (1) and the convex shape of the bottom layer (3) are similar to an off-axis paraboloid of revolution; the axis of the cover layer (1) is approximately coincident with the paraboloid-like axis of the bottom layer (3).

9. The LED package device with a light homogenizing cavity of claim 1, wherein N of the LED packages are assembled into a large area phototherapy device using flexible connectors, N is not less than 4.

10. A method of using the ultraviolet LED package device according to any one of claims 1-9 for non-disease treatment purposes, wherein the LED package device having a light homogenizing cavity is used to deliver light energy to an area of the skin to be irradiated of a user under stringent control of the light dose,

The light dose is equal to the product of the radiation source intensity and the radiation exposure time of the ultraviolet LED packaging device; the light source generates one or more wavelengths within the 293-310nm bandwidth; the light dose for irradiating the skin is 1-50 mJ/cm ²; the LED packaging device with the light homogenizing cavity irradiates the skin of a user with an area of about 1% -80% of the surface area of the human body.