KR100963636B1 - Manufacturing Method of Array Lighting Equipment - Google Patents

Abstract

Disclosed are an array-type lighting device and a method of manufacturing the same, which can provide a surface light source which is easy to manufacture and makes the light source invisible. Array type lighting device of the present invention disclosed a plurality of light emitting elements; A base substrate on which a plurality of light emitting elements are arranged; A cavity block formed on the base substrate, the cavity block having a plurality of cavities formed at a position corresponding to an arrangement position of the plurality of light emitting devices; A reflection plate block formed on the cavity block, the reflection plate block having a plurality of reflection plates formed at a position corresponding to the formation position of the plurality of cavities; And a diffusion film formed on the reflection plate block.

Description

Method of manufacturing an array type lighting device

The present invention relates to a method of manufacturing an array type lighting device, and more particularly, to a method of manufacturing an array type lighting device using a plurality of LED chips.

In general, LEDs (LEDs) are electronic components that generate injected minority carriers (electrons) using a p-n junction structure of a semiconductor and emit light by recombination of these minority carriers.

These LEDs are characterized by high-speed response and are widely used in display lamps and numeric display devices of various electronic devices such as display devices for automobile instrumentation and light sources for optical communication.

In particular, the LED can be used almost semi-permanently as well as excellent energy saving effect compared to the conventional light source. Therefore, these days, it is also used as an illumination light source that can replace the fluorescent lamp. For example, in order to implement the amount of light as in a fluorescent lamp, a plurality of LED packages 60 are installed on the metal base substrate 50 as in the lighting apparatus of FIG. 1. Here, the plurality of LED packages 60 is a light source.

In the lighting apparatus of FIG. 1, the base substrate 50 has a structure of molybdenum / copper / molybdenum. That is, the thermal conductivity of copper is very high, about 350 W / mK, but the coefficient of thermal expansion (CTE; about 16.5 ppm) is large. The thermal expansion coefficient (CTE; about 5 ppm) of molybdenum is similar to the coefficient of thermal expansion (CTE) of the body of each LED package 60 (eg, the combination of glass and ceramic) (the thermal expansion coefficient of glass is about 8 ppm). Therefore, molybdenum is disposed under the array type LED package 60.

 In the case of the lighting apparatus of FIG. 1, since the thermal conductivity of the base substrate 50 is high, heat generated from the array type LED package 60 may be quickly discharged to the outside, thereby minimizing heat generated from the lighting apparatus. In addition, the thermal expansion coefficient (CTE) of molybdenum (about 5 ppm) and the thermal expansion coefficient (CTE) of the body of the LED package 60 (for example, a combination of glass and ceramic) (the thermal expansion coefficient of glass is about 8 ppm) are similar to each other. There is little thermal mismatch.

However, the lighting apparatus of FIG. 1 has a problem in that the cost of molybdenum, which is a material of the base substrate 50, is very high, and the manufacturing cost is very high. In particular, the light source is directly visible when used as illumination. The light source is directly visible and does not feel good visually. In other words, it is not a surface light source such as a fluorescent lamp, but a point light source, so customer dissatisfaction increases rapidly.

Meanwhile, unlike FIG. 1, the light emitting device shown in FIG. 2 may be employed. 2 illustrates a single light emitting device. Array of a plurality of light emitting elements of Figure 2 is an array type lighting device. 2 includes a solid aluminum block 100 including a cavity 110 on one surface and an aluminum oxide coating film on one surface; Spaced first and second conductive traces 130a 'and 130b' present on the aluminum oxide coating of cavity 110; A semiconductor light emitting device 150 mounted in the cavity 110 and connected to the first and second conductive traces 130a 'and 130b' spaced apart from each other; A lens 170 extending across the cavity 110; And a sealant 160 positioned between the semiconductor light emitting device 150 and the lens 170. In FIG. 2, reference numeral 180 denotes a lens retainer for fixing the lens 170.

In the case of Figure 2 it is cumbersome to form a cavity 110 of the desired shape in the solid aluminum block 100. That is, the inclined surface and the bottom surface of the cavity 110 is used as the reflective surface, in particular, in the case of the bottom surface, the surface planarization should be made. In the case of FIG. 2, even if the cavity 110 is mechanically processed, there is a need for supplementary manual work to flatten the bottom surface of the cavity 110.

The present invention has been proposed to solve the above-described problems, and an object thereof is to provide a method of manufacturing an array-type lighting device that is easy to manufacture and does not show a light source.

Another object of the present invention is to provide a method of manufacturing an array type lighting device to provide a surface light source.

In order to achieve the above object, an array type lighting apparatus according to a preferred embodiment of the present invention, a plurality of light emitting elements; A base substrate on which a plurality of light emitting elements are arranged; A cavity block formed on the base substrate, the cavity block having a plurality of cavities formed at a position corresponding to an arrangement position of the plurality of light emitting devices; A reflection plate block formed on the cavity block, the reflection plate block having a plurality of reflection plates formed at a position corresponding to the formation position of the plurality of cavities; And a diffusion film formed on the reflection plate block.

The base substrate is made of a metal material of aluminum (Al) or a ceramic material of aluminum nitride (AlN).

The phosphor filter is provided in the opening of each cavity of the cavity block.

A diffusion control pattern is formed in the diffusion film.

The diffusion control pattern is formed in an uneven shape or an embossed shape.

A plurality of heat transfer mediums are additionally inserted into the base substrate, and the plurality of heat transfer mediums are inserted at positions corresponding to the arrangement positions of the plurality of light emitting elements.

Many thermal diesel media have a thermal conductivity higher than that of the base substrate.

The electrode pattern is inserted into the cavity block, but the end of the electrode pattern is exposed to the cavity side.

On the other hand, the manufacturing method of the array-type lighting device according to an embodiment of the present invention, the base substrate preparing step of preparing a base substrate; A light emitting device array step of arranging a plurality of light emitting devices on an upper surface of the base substrate; A cavity block stacking step of stacking a cavity block having a plurality of cavities formed at a position corresponding to an array position of the plurality of light emitting elements on a base substrate on which the plurality of light emitting elements are arrayed; A reflection plate block stacking step of stacking a reflection plate block having a plurality of reflection plates formed at a position corresponding to the formation position of the plurality of cavities on the cavity block; And a diffusion film forming step of installing a diffusion film on the reflection plate block.

The base substrate is made of a metal material of aluminum (Al) or a ceramic material of aluminum nitride (AlN).

The cavity block stacking step further installs a phosphor filter in the opening of each cavity of the cavity block.

A diffusion control pattern is formed in the diffusion film.

The diffusion control pattern is a concave-convex shape or an embossed shape.

The base substrate preparing step may include forming an insulating layer on the base substrate; And forming an electrode pattern on the insulating layer.

In the preparing of the base substrate, a plurality of holes are formed in the base substrate on which the electrode pattern is formed to insert a heat-transfer medium into each of the plurality of holes, and the plurality of holes are formed at positions corresponding to the array positions of the plurality of light emitting devices. It further comprises a step.

The cavity block stacking step includes inserting an electrode pattern into the cavity block while exposing an end of the electrode pattern to the cavity side.

The base substrate preparing step further includes forming a plurality of holes in the base substrate to insert a heat-transfer medium into each of the plurality of holes, but forming the plurality of holes at positions corresponding to the array positions of the plurality of light emitting devices. do.

According to the present invention having such a configuration, the light source is made invisible by covering the arrayed light emitting elements with the diffusion film.

When the base substrate, the cavity block, the reflector block, and the diffusion film are manufactured and combined in sequence, the desired array type illuminator is easily manufactured.

Light from a plurality of light emitting elements is further diffused by the diffusion film to be recognized as a surface light source. The point light source can be converted into a surface light source to meet the customer's surface light source requirements.

In particular, by forming a diffusion control pattern in the diffusion film, it is possible to further diffuse the light from a plurality of light emitting devices to become a surface light source more effectively. Of course, if the diffusion film and / or diffusion control pattern is changed in the manufacturing process, it is easy to manufacture the array-type lighting equipment having different directivity angle without replacing the entire lighting equipment.

Hereinafter, with reference to the accompanying drawings, an array-type lighting device and a method of manufacturing the same according to an embodiment of the present invention will be described. In the specification of the present invention, an array type lighting device is assumed and described as a lighting device in which a plurality of LED chips are arranged in a matrix form on a base substrate.

3 is a schematic exploded perspective view of an array type lighting device according to an embodiment of the present invention, and FIG. 4 is a cross-sectional view of the array type lighting device according to an embodiment of the present invention.

The array illuminator of the embodiment of the present invention comprises a plurality of LED chips 12; A base substrate 10 on which a plurality of LED chips 12 are arranged in a matrix form; A cavity block 20 formed on the base substrate 10 and having a plurality of cavities 22 formed at positions corresponding to the arrangement positions of the plurality of LED chips 12; A reflector block 30 formed on the cavity block 20 and having a plurality of reflecting plates 32 formed at positions corresponding to the positions of formation of the plurality of cavities 22; And a diffusion film 40 formed on the reflection plate block 30.

The base substrate 10 is made of a metal (for example, aluminum) of a flat plate, for example, about 1 mm thick. Aluminum is inexpensive compared to molybdenum and has a thermal conductivity of approximately 170 to 200 W / mK. In other words, aluminum has no difference in thermal conductivity as compared to molybdenum, and is cheaper, thus lowering manufacturing costs. In addition, the high thermal conductivity of aluminum lowers the thermal resistance of the array type lighting device. In addition, when aluminum is used, an insulating layer may be easily formed between the base substrate 10 and the electrode pattern when the electrode pattern is formed on the base substrate 10.

When the base substrate 10 is made of aluminum, an insulating layer (not shown) is formed on the upper surface of the base substrate 10 by anodizing (coating an aluminum surface). That is, an aluminum oxide (Al ₂ O ₃ ) film having a predetermined thickness is formed on the upper surface of the base substrate 10 by anodizing aluminum. When the aluminum oxide film is formed, the thermal expansion coefficient is small to reduce thermal mismatch with the LED chip 12. The formed aluminum oxide film is called an insulating layer. In this case, the insulating layer may have a thickness sufficient to serve as an insulator, and the thickness of the insulating layer is preferably as thin as possible in order to minimize thermal resistance in the insulating layer. The electrode pattern 14 is formed on the insulating layer by sputtering. The electrode pattern 14 is to be connected to the LED chip 12. In the electrode pattern 14, the left end portion 14a may be referred to as an anode, and the right end portion 14b may be referred to as a cathode.

In addition, you may use the material of the base substrate 30 as a ceramic material. If the base substrate 30 is made of a ceramic material, aluminum nitride (AlN) having a high thermal conductivity and a low thermal expansion coefficient is preferable.

In the case of the embodiment, the LED chip 12 is a general chip (e.g., with two electrodes on top of the chip) or a direct chip (e.g., with one electrode on the bottom of the chip and one electrode on the chip). ) Can be used.

Multiple cavities 22 of cavity block 20 may be formed by machining, etching, and other conventional techniques. The plurality of cavities 22 of the cavity block 20 are perforated. That is, since the cavity 110 of the solid aluminum block 100 of the prior art (see FIG. 2) is not perforated but formed to have a bottom surface, manual work for flattening the bottom surface of the cavity 110 should be additionally performed. Since the cavity 22 of the cavity block 20 of the embodiment of the invention is perforated, no manual work is required to planarize the floor surface.

The cavity block 20 may be made of a metal material or a ceramic material. Preferably, the cavity block 20 is made of a ceramic material.

Reflector block 30 is made of a material such as ceramic, metal, plastic. In the case of forming a pupil (replacement of the reflecting surface) in the existing solid aluminum block, a separate surface planarization process is required, but the reflector plate 32 of the reflector block block 30 according to the embodiment of the present invention may be used for injection molding, machining, and the like. By having a smooth surface. That is, the reflecting plate 32 of the reflecting plate block 30 of the present invention was perforated with a predetermined inclination angle, and the lower part of the pupil (which becomes the reflecting surface) of the existing solid aluminum block (see FIG. 2) was not perforated. That is, the side surface of the pupil of the reflecting plate 32 and the existing solid aluminum block during machining may be smoothly processed, but the bottom of the pupil of the existing solid aluminum block is difficult to be smoothly processed. Therefore, in the case of the existing solid aluminum block, the surface planarization process has to be additionally performed at the time of pupil formation.

The diffusion film 40 is horizontally disposed to be spaced apart from the reflective plate block 30 on the reflective plate block 30. The diffusion film 40 is preferably made of white. This is because the light emitted from the LED chip 12 becomes white light through the phosphor, and the white light passes through the diffusion film 40 to be reflected in white. The diffusion film 40 is manufactured using, for example, a diffuser of Al ₂ O ₃ . Since there may be a change in optical characteristics according to the blending ratio of the diffuser, the range for the blending ratio of the diffuser may be determined in consideration of the optical characteristics.

On one surface of the diffusion film 40 (that is, the surface facing the reflecting plate block 30), a diffusion control pattern 44 such as an uneven shape or an embossed shape may be formed. The diffusion control pattern 44 is formed at predetermined intervals in a direction orthogonal to the longitudinal direction of the diffusion film 40. The gap and depth of the unevenness or the embossing are determined in consideration of the aiming angle to be obtained. In the figure, although the diffusion control pattern 44 is shown in an uneven shape, it can be replaced by an embossed shape. It will be appreciated by those skilled in the art that the process of forming the diffusion control pattern 44 in the diffusion film 40 can be sufficiently performed by machining or the like. By forming the diffusion control pattern 44 in the diffusion film 40, the light from the plurality of LED chips 12 is further diffused to become a surface light source more effectively. Of course, if the diffusion film 40 and / or diffusion control pattern 44 in the manufacturing process is different, it is easy to manufacture the array-type lighting device having a different orientation angle without replacing the entire lighting device.

In the array type lighting device according to the embodiment of the present invention, as shown in FIG. 4, a plurality of LED chips 12 are arrayed on the base substrate 10, and the cavity block 20 and the reflector block 30 are sequentially stacked. The diffusion film 40 is laterally spaced apart from the upper portion of the reflector block 30 by the supporter 42. The diffusion film 40 has a strength that can be sufficiently leveled by the support 22. Each cavity 22 of the cavity block 20 is filled with a phosphor. Of course, if each LED chip 12 is capable of outputting white light, each cavity 22 is filled with silicon or epoxy instead of phosphor.

In FIG. 4, the diffusion film 40 is spaced apart from the reflector block 30 using the support 42, but the diffusion film 40 is not disposed on the upper surface of the reflector block 30 without using the support 42. You may make it lamination | stack.

5 is a flowchart illustrating a method of manufacturing an array type lighting device according to an embodiment of the present invention. In FIG. 5, it is assumed that the base substrate 10 is made of aluminum.

First, an insulating layer (not shown) is formed on the upper surface of the base substrate 10 of aluminum by anodizing (S10).

The electrode pattern 14 is formed on the insulating layer by sputtering or the like (S12).

A plurality of LED chips 12 are mounted at each mounting position (S14). At this time, each LED chip 12 is connected to the electrode pattern 14 of the corresponding position via a wire.

Thereafter, a plurality of cavities 22 are formed in the cavity block 20 having a predetermined thickness by machining or etching. The cavity block 20 in which the plurality of cavities 22 are formed is bonded to the upper surface of the base substrate 10 (S16). The formation position of the plurality of cavities 22 corresponds to the mounting position of the LED chip 12 mounted on the base substrate 10. Each cavity 22 is filled with a phosphor. In filling the phosphor, silicone or epoxy is used together as a submaterial.

A plurality of reflecting plates 32 are formed in the reflecting plate block 30 having a predetermined thickness. The reflective plate block 30 having the plurality of reflective plates 32 is bonded onto the cavity block 20 (S18). At this time, the position where the plurality of reflecting plates 32 are formed corresponds to the position where the cavity 22 of the cavity block 20 is formed. The reflecting plate 32 has a reflecting surface having a corresponding inclination angle to obtain a desired directing angle. Here, the orientation angle is not limited to the specified angle because it can be changed by the customer's order.

Subsequently, the diffusion film 40 is formed on the reflective plate block 30 so as to be spaced apart from the reflective plate block 30 using the supporter 42 or the like (S20). In other words, the diffusion film 40 covers the plurality of LED chips 12.

In this way, the array-type lighting apparatus according to the embodiment of the present invention is completed. When the power is applied, the light emitted from the plurality of LED chips 12 is straight or reflected to each reflecting plate 32 to be directed toward the diffusion film 40. The light diffused through the diffusion film 40 illuminates the subject, and when viewed from the outside, not only the light source (LED chip) is visible but also recognized as a surface light source.

6 is a cross-sectional view for explaining a modification of the array-type lighting apparatus according to the embodiment of the present invention. In FIG. 6, not all of the plurality of LED chips are shown, but one LED only shows the LED chip and its peripheral components. It will be apparent to those skilled in the art that the LED package of FIG. 6 is disposed in each region of FIG. 4 to form an array lighting device.

6, the phosphor filter 16 is further formed in an opening of each cavity 32 of the cavity block 30, and a plurality of heat-transfer mediums are formed on the base substrate 10. The difference is that (5) is additionally inserted.

In FIG. 4, it is assumed that phosphors are filled in the cavities 22 of the cavity block 20. If there is an error in the filling amount of the phosphor, the upper surface of the filled phosphor layer may be concave or convex. In this case, a problem arises in the optical properties and is treated as a defective product. In FIG. 6, in order to prevent this, a flat sheet-shaped phosphor filter 16 is manufactured and installed horizontally in the opening of each cavity 22 of the cavity block 20. Here, the sheet-shaped phosphor filter 16 is manufactured with yellow phosphor as a main component. This is a case where the LED chip 12 outputs blue light, and is for producing white light. If the color of the light output from the LED chip 12 is a color other than blue, the color of the phosphor filter 16 should also be changed to produce white light (see Patent Registration No. 0772648). The sheet-shaped phosphor filter 16 may be manufactured using a transparent glass plate and a phosphor.

In the case of using the phosphor filter 16 as shown in FIG. 6, the cavity in the cavity block 20 may be filled with silicon (or epoxy) or air.

The insertion of the plurality of heat-transfer mediums 5 into the base substrate 10 is intended to help quickly release heat generated from the LED chip 12. The plurality of thermal oil mediums 5 are inserted at positions corresponding to the arrangement positions of the plurality of LED chips 12. That is, since the portion immediately below the LED chip 12 is the position where the heat is first and the most, the heat is preferentially rapidly dissipated through the thermal medium 5. The thermal diesel medium 5 is configured in a shape such as a cylinder, a square pillar, a pentagonal pillar, or the like. More preferably, the diameter of the heat oil medium 5 is larger than the lower area of the corresponding LED chip 12.

The thermal oil medium 5 preferably has a higher thermal conductivity than that of the base substrate 10. For example, the heat oil medium 5 uses a material having high thermal conductivity such as copper slug, diamond slug or the like. The thermal conductivity of copper is about 350 W / mK. Pure diamond has a thermal conductivity of approximately 2000 W / mK. Diamond slugs are industrial diamonds. Diamond slugs consist of CVD diamond having a thermal conductivity of approximately 1000 W / mK by the addition of impurities in the manufacturing process. CVD diamond refers to polycrystalline diamond synthesized by using a gas such as hydrogen and methane through a heat source such as plasma at high temperature. When the diamond slug is employed as described above, heat dissipation is quicker than in other embodiments because the thermal conductivity is very high.

Diamond slugs, on the other hand, have a coefficient of thermal expansion of approximately 3 × 10 ⁻⁶ / ° C. The coefficient of thermal expansion of copper is 16 × 10 ⁻⁶ / ° C. The thermal expansion coefficient of the LED chip 12 is approximately 6 × 10 ⁻⁶ / ° C. If the heat-transfer medium 5 is made of copper slug in FIG. 6, problems of thermal expansion and contraction at the bonding interface between the LED chip 12 and the copper slug may occur depending on the temperature change (difference). However, when the thermal diesel medium 5 is made of diamond slug, the thermal conductivity is much higher than that of copper slug, and the thermal expansion coefficient is similar to that of the LED chip 12 in terms of thermal expansion coefficient. The peeling phenomenon can be prevented.

In order to insert the heat-transfer medium 5 into the base substrate 10, a hole is first formed in the base substrate 10, and then the heat-transfer medium 5 is inserted into the hole. Here, the hole is formed at a position corresponding to the position where the LED chip 12 is arrayed.

As such, when the heat-transfer medium 5 is additionally inserted into the base substrate 10, heat dissipation is faster than in the structure of FIG. 4, thereby lowering the thermal resistance of the array type lighting device.

In FIG. 6, the electrode pattern 14 is inserted into the cavity block 20. That is, the electrode pattern 14 is inserted into the cavity block 20 so that one side of the electrode pattern 14 is exposed to the cavity 22 side to be connected to the LED chip 12.

In the modification of FIG. 6, the heat-transfer medium 5 has a lower heat resistance of the base substrate 10 than in the embodiment. In particular, in the modification of FIG. 6, the electrode pattern 14 may be inserted into the cavity block 20, thereby eliminating the step of forming an electrode by sputtering on the base substrate 10. This has the effect of reducing the expensive cost of sputtering.

The manufacturing of the array type lighting device employing the structure of FIG. 6 is almost similar to the manufacturing process description of the above-described embodiment. What is necessary is just to insert the heat-transmission medium 5 into the hole formed in the base substrate 10 in the preparation of the base substrate 10.

The electrode pattern 14 may be inserted into the cavity block 20 without being formed on the base substrate 10. In order to insert the electrode pattern 14 into the cavity block 20, the cavity block 20 may be formed by stacking a multilayer ceramic substrate.

The phosphor filter 16 and the heat oil medium 5 of FIG. 6 can be employed in the structure of FIG.

In FIG. 6, since the electrode pattern 14 is positioned in the middle of the cavity block 20, the LED chip 12 uses a general chip (for example, two electrodes on the chip).

On the other hand, the present invention is not limited only to the above-described embodiments and can be carried out by modifications and variations within the scope not departing from the gist of the present invention, the technical idea that such modifications and variations are also within the scope of the claims Must see

1 and 2 are views for explaining the problem of the conventional array-type lighting equipment.

3 is a schematic exploded perspective view of an array type lighting device according to an embodiment of the present invention.

4 is a cross-sectional view of an array-type lighting device according to an embodiment of the present invention.

5 is a flowchart illustrating a method of manufacturing an array type lighting device according to an embodiment of the present invention.

6 is a cross-sectional view for explaining a modification of the array-type lighting apparatus according to the embodiment of the present invention.

Description of the Related Art

10: base substrate 12: LED chip

20: cavity block 22: cavity

30: reflector block 32: reflector

40 diffusion film 44 diffusion control pattern

Claims (16)

delete delete delete delete delete delete delete A base substrate preparing step of preparing a base substrate of a flat plate; A light emitting device array step of arranging a plurality of light emitting devices on an upper surface of the base substrate; A cavity block stacking step of stacking a cavity block having a plurality of cavities perforated at a position corresponding to an array position of the plurality of light emitting elements on the base substrate on which the plurality of light emitting elements are arrayed; A reflection plate block stacking step of stacking a reflection plate block formed with a plurality of reflection plates perforated at a position corresponding to the formation position of the plurality of cavities on the cavity block; And And a diffusion film forming step of installing a diffusion film on the reflection plate block. The method according to claim 8, The base substrate is a manufacturing method of an array type lighting device, characterized in that consisting of a metal material of aluminum (Al) or a ceramic material of aluminum nitride (AlN). The method according to claim 8, In the cavity block stacking step, a phosphor filter is further installed in an opening of each cavity of the cavity block. The method according to claim 8, The diffusion film manufacturing method of the array type lighting device, characterized in that to form a diffusion control pattern. The method according to claim 11, The diffusion control pattern is a concave-convex shape or embossed shape manufacturing method of an array-type lighting device characterized in that. The method according to any one of claims 8 to 12, The preparing of the base substrate may include forming an insulating layer on the base substrate; And forming an electrode pattern on the insulating layer. 14. The method of claim 13, In the preparing of the base substrate, a plurality of holes are formed in the base substrate on which the electrode pattern is formed to insert a heat-transfer medium into each of the plurality of holes, and the plurality of holes correspond to the array positions of the plurality of light emitting devices. Method for manufacturing an array-type lighting device, characterized in that it further comprises the step of forming in a position. The method according to any one of claims 8 to 12, The cavity block stacking step may include inserting an electrode pattern into the cavity block, but exposing an end portion of the electrode pattern to the cavity side. The method according to claim 15, The preparing of the base substrate may include forming a plurality of holes in the base substrate to insert a heat-transfer medium into each of the plurality of holes, and forming the plurality of holes at positions corresponding to the array positions of the plurality of light emitting devices. Method for producing an array-type lighting device, characterized in that it further comprises the step.

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