CN212257394U - Light-emitting diode - Google Patents

Abstract

A light emitting diode belongs to the field of light emitting diodes. The light emitting diode comprises a carrier, a luminous body and a lens. The carrier is provided with a substrate and a box dam formed on the substrate, and the box dam and the substrate jointly limit a die bonding area. The luminous body is positioned in the die bonding area and fixed on the substrate. The lens is provided with a transparent substrate and fluorescent powder distributed in the transparent substrate, and the fluorescent powder covers the carrier to encapsulate the luminous body in the solid crystal area. The luminous body is provided with a luminous group consisting of at least three luminous chips which are arranged in a linear mode; wherein, in at least three light emitting chips, the light emitting wave bands of two adjacent light emitting chips do not coincide with each other. The light emitting diode can obtain better color consistency on the premise of simultaneously adopting the light emitting chips with three light emitting wave bands.

Description

Light-emitting diode

Technical Field

The application relates to the field of light emitting diodes, in particular to a light emitting diode.

Background

In a conventional Light Emitting Diode (LED) based On a Chip On Board (COB) structure, the Light Emitting Chip is generally disposed On a circuit layer of a substrate, and a dispensing region of phosphor paste is formed by pressing a circle of plastic package material On the periphery of the Light Emitting Chip. Or a circle of white silica gel is drawn on the substrate through a dispenser to serve as a box dam, LED chips with the same wavelength are arranged in the area in the box dam and then are electrically connected, and then fluorescent powder formula blending is carried out according to the wavelength of the LED chips. The current LED often shows a problem of poor color consistency, which is a problem to be solved urgently.

SUMMERY OF THE UTILITY MODEL

In order to improve and even solve the problem of poor color consistency of white light LEDs, the application provides a light emitting diode.

The application is realized as follows:

in a first aspect, examples of the present application provide a light emitting diode.

The light emitting diode includes a carrier, a light emitter, and a lens.

The carrier is provided with a substrate and a box dam formed on the substrate, and the box dam and the substrate jointly limit a die bonding area. The light-emitting body has selected characteristic light, is located in the die bonding area and is fixed on the substrate. The lens is provided with a transparent substrate and fluorescent powder distributed in the transparent substrate, and covers the carrier so as to encapsulate the luminous body in the solid crystal region. The luminous body is provided with a luminous group consisting of at least three luminous chips which are arranged in a linear mode; wherein, in at least three light emitting chips, the light emitting wave bands of two adjacent light emitting chips do not coincide with each other.

By arranging the light-emitting chips with different light-emitting wavebands in a crossed manner, when the light-emitting chips with different light-emitting wavebands are used in a combined manner, excitation light with better monochromaticity can still be generated, so that the consistency of the light-emitting colors of the white light-emitting diode is improved. In addition, because the structure can use the light-emitting chips with different light-emitting wave bands, different white light-emitting diodes do not need to be manufactured in batches aiming at the light-emitting chips with different wave bands, so that the manufacturing complexity can be reduced (if the light-emitting chips with different wave bands do not need to adopt different fluorescent powder), the production efficiency is improved, and the production cost is reduced.

With reference to the first aspect, in a first possible implementation manner of the first aspect of the present application, the luminaire has at least two light emitting groups, all of which are arranged in a row; alternatively, the luminous body has at least two light-emitting groups, and all the light-emitting groups are arranged in a row in a manner that the adjacent light-emitting groups are equally spaced.

The mode allows more light emitting chips to be arranged, and the white light LED with a large light emitting surface is manufactured on the premise of keeping proper color consistency.

With reference to the first aspect or the first implementation manner of the first aspect, in a third possible implementation manner of the first aspect of the present application, the light emitter features blue light, and the light emitting chip has a first type chip with a light emitting band of 450 to 452.5 nanometers, a second type chip with a light emitting band of 452.5 to 455 nanometers, or a third type chip with a light emitting band of 455 to 457.5 nanometers.

With reference to the first aspect, in a third possible implementation of the first aspect of the present application, the substrate has one or more of the following limitations: the first defined, fixed emitter surface is a mirror surface; a second definition, the substrate is thermally conductive; third, the substrate is aluminum.

When the surface of the substrate is a reflecting mirror surface, the light intensity/brightness of the light-emitting diode can be improved, and the light loss can be reduced. The substrate is made of heat conducting materials, so that the phenomenon of heat accumulation during the working of the light-emitting diode can be avoided, the phenomenon that the light-emitting chip is damaged (dead light) due to the heating can be avoided, and the service life of the light-emitting diode can be prolonged.

With reference to the first aspect, in a fifth possible implementation manner of the first aspect of the present application, the substrate has a positioning member; or the substrate is provided with a positioning hole which penetrates through the substrate.

The base plate is provided with a positioning hole and a positioning piece, so that the installation and the fixation are convenient.

In a first possible embodiment of the sixth aspect of the present application in combination with the first aspect, the transparent substrate is a silica gel.

In the implementation process, the light emitting diode provided by the embodiment of the application adopts the light emitting chips with different wave bands, and the light emitting of the light emitting chips can be stable and uniform through the selection of the arrangement mode of the light emitting chips, so that the consistency of the light emitting colors of the diode is facilitated.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings that are required to be used in the embodiments will be briefly described below, it should be understood that the following drawings only illustrate some embodiments of the present application and therefore should not be considered as limiting the scope, and for those skilled in the art, other related drawings can be obtained from the drawings without inventive effort.

FIG. 1 is a schematic diagram of the structure of a carrier in an example of the present application;

fig. 2 is a schematic structural diagram of a light emitter in an example of the present application;

FIG. 3 is a schematic view of the cooperative arrangement of the carrier of FIG. 1 and the emitter of FIG. 2;

fig. 4 is a schematic structural diagram of a light emitting diode in the present example;

fig. 5 shows a process flow diagram for fabricating the light emitting diode of fig. 4.

Icon: 100-a carrier; 101-a substrate; 102-positioning holes; 103-positive connecting wire; 104-negative connection line; 105-a solid crystal region; 106-positive electrode pad; 107-negative electrode pad; 108-box dam; 200-a light emitter; 201-first type chip; 202-second type chip; 203-third type chip; 204-a wire; 300-a light emitting diode; 301-fluorescent powder; 302-transparent substrate.

Detailed Description

White LEDs can produce white light in three ways:

1. a blue LED is used to excite a yellow emitting phosphor. That is, a blue LED and a YAG fluorescent substance, for example, are spatially placed together, and the blue light emitted from the blue LED excites the fluorescent substance, whereby the blue light and yellow light emitted from the phosphor excited are mixed to form white light.

2. And exciting the R-G-B fluorescent powder by using an ultraviolet LED. Based on the principle of three primary colors mixing, the purple light emitted by the purple LED is used for exciting three kinds of fluorescent powder, so that the fluorescent powder generates three colors of red, green and blue, and white light is generated by mixing.

3. The white light is achieved by adjusting the respective brightness of the 3 types of red, green and blue LEDs.

One key index for measuring the light emitting performance of a white light LED is the uniformity of the light emitting color. However, the above color consistency is often a difficulty. Moreover, such a problem is particularly prominent in the first white light generation method.

As a result of the research, the inventors found that the main cause of the problem is the problem of light emission for a blue LED as excitation light. Specifically, in an actual manufacturing process, when a chip manufacturer manufactures a blue LED, the blue LED is usually divided into 2-3 wavelength bands according to the wavelength band of the blue light emitted by the chip manufacturer, and each wavelength band differs by 2.5 nm. Therefore, when manufacturing white LEDs, separate batch production is required according to excitation LEDs (i.e., blue LEDs).

In addition, because the light-emitting wavelength bands of the excitation LEDs are different, the excitation LEDs with different wavelength bands need fluorescent powder with different formulas to be matched with the excitation LEDs, and the consistency of the light-emitting colors can be more ideal through the mode.

However, the light sources produced by different wavelengths and different formulas have different light emission colors, so even if the white light LEDs are produced in batches by using the corresponding fluorescent powder formula according to the light emission wavelength band of the excited LEDs, the light emission consistency of the white light LEDs is not good by using the fluorescent powder with the same formula.

Moreover, the batch production method also results in high production management cost and large tail number. Meanwhile, because the color consistency is not well controlled, the risk of material scrapping caused by single mixing and mixed mixing is existed.

In addition, with the development and the great popularization of the COB light source, the requirement on the uniformity of the COB light-emitting color is higher and higher, and the COB light-emitting color is more and more sensitive to the cost. The existing batch production can not meet the requirements.

In summary, the problems of the existing white light LED which generates white light by the cooperation of the excitation LED and the fluorescent powder mainly include the problems of batch production by different wavelengths, more batches, more mantissas, high cost and easy material mixing, and the problem of poor color consistency caused by the formula difference.

In view of the above problems, the inventor creatively proposes to combine the excitation LEDs of each wavelength band to use them, so as to change the arrangement of the excitation LEDs of each wavelength band to make the light emission more stable and uniform, unlike the aforementioned solution of manufacturing white LEDs in batches according to the difference of the light emission wavelength band of the excitation LEDs. Therefore, the effect produced by the combination of the excitation LEDs of different wave bands can be relatively more uniform through the improvement of the arrangement mode of the excitation LEDs of different wave bands.

This approach may also achieve the additional effect that for this more uniform "synthetic excitation light", a single formulation of phosphor may be used without having to select different formulations of phosphor for different wavelength bands of the excitation LEDs.

Therefore, the excited LED emits light more uniformly, and the formula of the fluorescent powder is single, so that the white light LED does not need to be manufactured in batches, the consistency of the emitted light color is improved, and the problems are improved and even solved to a great extent.

The solution described above will be elucidated below in connection with a light emitting diode in an example of the present application.

An example light emitting diode includes a carrier, a light emitter, and a lens. Wherein, the luminous body and the lens are fixed and installed by depending on the carrier. The light emitted by the luminous body is emitted out through the lens. The light-emitting diode has improved light-emitting color consistency and low manufacturing cost, can be applied to the fields of high-quality household illumination, commercial illumination and the like, and has very wide application prospect.

Referring to fig. 1, a carrier 100 mainly includes a substrate 101 and a dam 108.

As the name implies, the substrate 101 has a plate-like structure and a relatively small thickness. It may be made of various materials selected from metals such as aluminum plate, plastic plate, resin plate, etc., without being particularly limited. The thickness, size, material, etc. of the substrate 101 may be selected according to actual needs. The dimensions of the substrate 101 are selected, for example, according to the dimensions of the lamp in which the white light diode is fabricated.

The dam 108 is a structural body fixed to the surface of the substrate 101. The surface thereof mainly refers to any one surface (e.g., upper or lower surface) of the carrier 100 in the thickness direction. Typically, the dam 108 and the substrate 101 are separately fabricated and then joined together by any suitable means. For example, the enclosure may be made of ceramic or organic material and then bonded by using glue (e.g., epoxy glue), or may be attached by electroplating. In other examples, the shroud plate and the substrate 101 may also be integrally formed, for example, by injection molding, extrusion, or the like, and made of an organic polymer material.

Generally, the dam 108 is disposed on the surface of the substrate 101 in a ring-shaped configuration, and thus defines an area on the surface of the substrate 101. The solid crystal region 105 is defined by the dam 108 and the substrate 101, and the solid crystal region 105 is used for mounting the light emitter 200. Since the light emitting chips in the die bonding area 105 emit light, which may generate working heat and heat accumulation due to illumination, the dam 108, the substrate 101, and the light emitting chips may be damaged or risked to some extent, and therefore, the material of the substrate 101 may be selected so as to be easily conductive to heat, thereby preventing heat from accumulating in the die bonding area 105. In addition, in order to increase the light extraction rate, the shape of the surface of the substrate 101 of the solid crystal region 105 may be controlled so that more light can be emitted. For example, the surface of the fixed illuminant 200 is a mirror surface. Illustratively, when the substrate 101 is an aluminum plate, the surface thereof may be ground and polished so that the area is mirror-finished.

In addition to the above modifications to the substrate 101, further modifications to the substrate 101 may be made based on subsequent applications. For example, when the light emitting diode 300 obtained as described above is manufactured as a lighting apparatus, the substrate 101 can be fixed to a selected object, and thus, a positioning member can be manufactured on the substrate 101. The positioning element may be a raised structure or a recessed structure or a notch or the like formed on the surface of the substrate 101. Illustratively, the positioning member may be selected as a positioning hole 102, which is disposed through the substrate 101. Thus, the locating holes 102 can be used for both locating and mounting and securing (e.g., by bolting to a selected object). The positioning holes 102 may be one or more, and in the example, for the substrate 101 having a rectangular structure, the positioning holes 102 have two ends distributed in the direction of the two diagonal lines.

In addition, in order to facilitate the extraction of electrodes from the light emitter 200, a positive electrode pad 106, a positive electrode connection line 103, a negative electrode pad 107, and a negative electrode connection line 104 are formed on the substrate 101. The positive electrode pad 106 is integrally connected to the positive electrode connection line 103, the positive electrode pad 106 is located at a corner of the substrate 101, and the positive electrode connection line 103 has a semicircular structure. The negative electrode pad 107 is integrally connected to the negative electrode connecting wire 104, the negative electrode pad 107 is located at the other corner of the substrate 101, and the negative electrode connecting wire 104 has a semicircular structure. Also, the positive electrode connection line 103 and the negative electrode connection line 104 are also arranged annularly around the periphery of the solid crystal region 105 (circular region).

The light emitting body 200 is an excitation light source for generating excitation light to excite the phosphor 301 to emit light, and is exemplified by a blue LED. Of course, the light emitter 200 may alternatively be a green LED or a red LED in other examples. In other words, the luminaire 200 has a certain characteristic light. As described above, the light emitter 200 in the present application is a combination of a plurality of light emitting chips, and thus, the characteristic light mainly means that the light emitting colors of the respective light emitting chips are all one type of light. For example, each light emitting chip generates blue light, although the blue light band of each light emitting chip is different.

Illustratively, the light emitter 200 features blue light. Short-wave blue light is known to have a wavelength between 400nm and 480nm, i.e. a wavelength band between 400nm and 480 nm. Thus, in one example, the light emitting chips constituting the aforementioned light emitter 200 may have three types. Wherein, the light emitting chip has a first type chip 201 with a light emitting waveband of 450 to 452.5 nanometers; the light emitting chip has a light emitting band of 452.5 to 455 nanometers and is a second type chip 202; the light emitting chip has a light emitting band of 455 to 457.5 nm and is the third type chip 203. The three types of chips, although different in wavelength band and distributed spectrally continuously and adjacently, all belong to the blue wavelength band.

Therefore, the light emitter 200 in the present example is configured with at least three light emitting chips. In general, in the led 300, the light emitter 200 may be composed of one or more (e.g., two, three, or more) light emitting groups. As an arrangement, when the light emitting body 200 has at least two light emitting groups, all the light emitting groups are arranged in a row. Alternatively, further, the light emitter 200 has at least two light emitting groups, and all the light emitting groups are arranged in a row with the adjacent light emitting groups being equally spaced apart from each other.

Referring to fig. 2, in the example of the drawings, the light emitting body 200 has eight light emitting groups, and the light emitting chips in each light emitting group are linearly arranged in the vertical direction, and the eight light emitting groups are equally spaced in the horizontal direction.

Also, the light emitting chips in the light emitting group in the above description are arranged in a linear manner, and have at least three light emitting chips. Meanwhile, in the light emitting group, the light emitting wave bands of two adjacent light emitting chips do not coincide with each other. As an example of the light emitting group formed by one chip of each of the three types, the three chips in the light emitting group may be arranged in the following manner: first type chip 201-second type chip 202-third type chip 203.

In the present application, excitation LEDs of different wavelength bands of the same color are arranged in groups and form light emitting groups. And in one light emitting group, the excitation LEDs of different light emitting bands are arranged in a crossed manner. Namely, the light-emitting wave bands of two adjacent exciting LEDs are not coincident. For example, for the three types of chips, i.e., the first type chip 201, the second type chip 202, and the third type chip 203, in the same light emitting group including three light emitting chips, the first type chip 201, the second type chip 202, and the third type chip 203 may be arranged, or the first type chip 201, the third type chip 203, and the second type chip 202 may be arranged, or the second type chip 202, the first type chip 201, and the third type chip 203 may be arranged, and so on. In the same light emitting group including four light emitting chips, the first type chip 201, the second type chip 202, the third type chip 203, and the first type chip 201 may be arranged, or the first type chip 201, the third type chip 203, the second type chip 202, and the first type chip 201 may be arranged, or the second type chip 202, the first type chip 201, the third type chip 203, and the first type chip 201 may be arranged, and so on.

In the above manner, by arranging the light emitting chips of different wavelength bands in a crossing manner, the color uniformity of the excitation light of the light emitter 200 as a whole can be improved. The non-intersecting arrangement means that the emission wavelength bands of two adjacent light-emitting chips are the same in one light-emitting group. As an example of the non-crossed arrangement, in a light emitting group composed of four light emitting chips, the chips are arranged in the manner of, for example, a first type chip 201, a second type chip 202, a third type chip 203; or, the second type chip 202, the third type chip 203, the first type chip 201; or a third type chip 203, a second type chip 202, a first type chip 201.

After determining the light-emitting wavelength band of the light-emitting chip to be used, the phosphor 301 may be selected according to the light-emitting wavelength of the light-emitting chip to be used, so as to improve the matching degree between the light-emitting chip and the phosphor 301. The phosphor 301 is selected according to the average value of the light emission wavelength bands of all the light emitting chips in the light emitting group. Illustratively, in the aforementioned three types of light-emitting chips, the average value of the light-emitting wavelengths of the three types of chips is calculated with the center wavelength of the light-emitting wavelength band of each light-emitting chip as a reference, and the phosphor 301 is selected for this average value.

For example, a first chip emitting light in a wavelength band of 450 to 452.5 nm; a second chip having a light emission wavelength band of 452.5 to 455 nm; the third emission band is 455 to 457.5 nm. The average value a of the blue wavelengths of the three light emitting chips is 453.75, and is calculated as (a1+ a2+ a 3)/3.

Wherein, a1 ═ (450+ 452.5)/2; a2 ═ (452.5+ 455)/2; a1 ═ (455+ 457.5)/2.

As the requirement of power supply, each light-emitting LED leads out a positive electrode and a negative electrode through a lead 204. All of the light-emitting LEDs in the light-emitting body 200 may be combined in series, parallel, or the like. The manner of the extraction electrodes of the individual light emitting chips and the arrangement with the carrier 100 are disclosed in fig. 3.

The lens is a component for protecting the light-emitting chip and is also responsible for reasonably guiding out the light generated by the light-emitting chip. In the example, the lens includes a transparent substrate 302 and a phosphor 301, and the lens covers the carrier 100 to encapsulate the light emitter 200 in the die attach region 105 of the carrier 100. Typically, the transparent substrate 302 is provided by a glue that can be cured, and the phosphor 301 powder is mixed in the glue during actual manufacturing to form a viscous substance (e.g., silica gel phosphor 301 mixed glue, accordingly, the transparent substrate can be selected to be silica gel). Then, it is attached to the carrier 100 by coating or the like to fix the light emitting chip.

To make the application easier for a person skilled in the art to carry out, a method of manufacturing a light emitting diode 300 as shown in fig. 4 is given as an example.

The method comprises the following steps, see fig. 5.

Step S101, a substrate 101 is produced.

The substrate 101 can be made by shaping, polishing, etc. an aluminum material, and a mirror aluminum plate having a smooth surface and good reflection characteristics is formed.

Step S102, a light emitter 200 is manufactured.

On the mirror surface of the substrate 101, a light emitting chip, i.e., die bonding, is mounted. Specifically, a circular area is selected as the die bonding area 105 on the mirror surface, and then each die-attaching line (e.g., eight lines, not shown) parallel to and spaced apart from the diameter of the die bonding area 105 is selected as a fixed reference line of the die. And placing the light-emitting chips at intervals by taking the arrangement lines as the arrangement direction of the chips. For example, in fig. 3, based on the diagram, the rightmost side of the light emitter 200 has four light emitting chips (constituting one light emitting group) arranged at intervals from top to bottom, and the four light emitting chips are connected in series in sequence.

Specifically, in a light emitting group defined by any one of the arrangement lines, at least three light emitting chips (e.g., four, 9, etc. in the example) are fixed at intervals in a linear arrangement, and in the same light emitting group (defined by one of the aforementioned arrangement lines), the light emitting wavelength bands of adjacent two light emitting chips do not coincide with each other. Thus, the A wave band chip, the B wave band chip and the C wave band chip are sequentially arranged.

When the light emitter 200 has fewer light emitting chips, for example, three light emitting chips, the light emitter 200 may form a light emitting group, and the light emitting group is fixed at any suitable position in the die bonding region 105. When it is required to fabricate the light emitter 200 with fewer light emitting chips, for example, 112 light emitting chips as shown in fig. 2, it may be planned as eight light emitting groups, and the number of light emitting chips of each light emitting group may be 4, 9, 11, 12, 11, 9, 4 in sequence. In such an example, the eight light emitting groups are arranged in a row, and adjacent two light emitting groups are spaced apart by a given distance.

Step S103, the light emitter 200 is pulled out of the positive electrode and the negative electrode.

As described above, the substrate 101 has the positive connection line 103 and the negative connection line 104, so that the light emitting chips in the light emitter 200 are connected in series or in parallel by the wires 204 and then electrically connected to the corresponding positive connection line 103 and negative connection line 104. The positive electrode connection line 103 and the negative electrode connection line 104 are connected to a positive electrode pad 106 and a negative electrode pad 107, respectively. Therefore, the electrode extraction of the light-emitting chip is realized through the mode.

Step S104, disposing a dam 108 on the substrate 101 to confine the light emitting group within the dam 108.

The dam 108 may be generally formed by enclosing the light emitter 200 with glue by "drawing" a ring around the periphery of the light emitter until the glue cures.

And step S105, packaging.

The prepared mixed glue containing the phosphor 301 is applied on the above structure (e.g., inside the dam 108) to completely seal the light emitter 200. And forming a packaging body loaded with the fluorescent powder 301, namely a lens after the glue is cured.

In the description of the present application, it should be noted that the terms "center", "upper", "lower", "right", "vertical", "horizontal", "inner", "outer", and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings or orientations or positional relationships that are conventionally placed when products of the application are used, and are used only for convenience in describing the application and simplifying the description, but do not indicate or imply that the devices or elements to be referred to must have a specific orientation, be constructed in a specific orientation, and be operated, and thus, should not be construed as limiting the application. Furthermore, the terms "first," "second," "third," and the like are used solely to distinguish one from another and are not to be construed as indicating or implying relative importance.

The above description is only a preferred embodiment of the present application and is not intended to limit the present application, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, improvement and the like made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims (10)

1. A light emitting diode, comprising:

the wafer fixing device comprises a carrier, a wafer fixing device and a wafer fixing device, wherein the carrier is provided with a substrate and a dam formed on the substrate, and the dam and the substrate jointly define a wafer fixing area;

the luminous body is provided with characteristic light with a selected color, is positioned in the die bonding area and is fixed on the substrate;

the lens is provided with a transparent substrate and fluorescent powder distributed in the transparent substrate, and covers the carrier so as to encapsulate the luminous body in the solid crystal region;

the luminous body is provided with a luminous group consisting of at least three luminous chips which are arranged in a linear mode;

wherein, in the at least three light emitting chips, the light emitting wave bands of two adjacent light emitting chips do not coincide with each other.

2. The led of claim 1, wherein said light emitter has at least two of said light emitting groups, all of said light emitting groups being arranged in a row.

3. The led of claim 2, wherein all of said light emitting groups are arranged in a row with adjacent light emitting groups equally spaced apart.

4. The led of any one of claims 1 to 3, wherein the light emitter is characterized by blue light, and the light emitting chips have a first type of chip with a light emission band of 450 to 452.5 nm, a second type of chip with a light emission band of 452.5 to 455 nm, and a third type of chip with a light emission band of 455 to 457.5 nm.

5. The led of claim 1, wherein the surface of said substrate to which said light emitter is attached is a mirror surface.

6. The light-emitting diode according to claim 1 or 5, wherein the substrate is thermally conductive.

7. The led of claim 1, wherein said substrate is aluminum.

8. The led of claim 1, wherein the substrate has a positioning element.

9. The light-emitting diode of claim 8, wherein the positioning element is a positioning hole penetrating through the substrate.

10. The led of claim 1, wherein said transparent substrate is a silicone gel.

Images