Light emitting device

Abstract

The invention provides a light-emitting device, and belongs to the technical field of photoelectricity. The light-emitting device comprises a frame body, a substrate, a heat sink, a light-emitting chip and a protection device, the frame body and the heat sink are both fixed to the substrate, and the heat sink is located in the frame body. The light-emitting chip and the protection device are fixed to the heat sink, and a gap is formed between the light-emitting chip and the protection device in the length direction of the heat sink. Since the light-emitting chip and the protection device are not arranged in parallel along the width direction of the heat sink, a safe distance does not need to be reserved between the light-emitting chip and the protection device in the width direction, the size occupied by the light-emitting chip and the protection device in the width direction can be reduced, the width of the light-emitting device is reduced, and the light-emitting efficiency is improved. And the miniaturization of the light-emitting device is facilitated.

Description

Technical Field

[0001] The present disclosure relates to the field of optoelectronic technology, and in particular to a light-emitting device. Background Art

[0002] The light emitting device can convert the received electrical signal into an optical signal, thereby emitting laser light outward. The light emitting device includes a frame, a substrate, a heat sink, a light emitting chip and a protective device. The frame and the heat sink are fixed to the substrate, and the heat sink is fixed inside the frame. The light emitting chip and the protective device are fixed to the heat sink.

[0003] In the related art, the light-emitting chip and the protective device are arranged side by side along the width direction of the heat sink, and a certain safety distance is required between the light-emitting chip and the protective device in the width direction to avoid collision between the light-emitting chip and the protective device when placing them.

[0004] As a result, the width of the light emitting device in the related art is relatively wide, which is not conducive to miniaturization of the light emitting device. Summary of the invention

[0005] The present disclosure provides a light-emitting device, which can solve the technical problems existing in the related art. The technical solution of the light-emitting device is as follows:

[0006] The present disclosure provides a light-emitting device, which includes a frame, a substrate, a heat sink, a light-emitting chip and a protection device;

[0007] The frame and the heat sink are both fixed on the substrate, and the heat sink, the light emitting chip and the protection device are all located inside the frame;

[0008] The light emitting chip and the protection device are both fixed on the heat sink, and there is a distance between the light emitting chip and the protection device in the length direction of the heat sink.

[0009] In a possible implementation manner, projections of the light-emitting chip and the protection device along the length direction of the heat sink at least partially overlap.

[0010] In a possible implementation manner, all projections of the light-emitting chip in the length direction of the heat sink fall on the projection of the protection device in the length direction of the heat sink.

[0011] In a possible implementation manner, the projection of the protection device in the length direction of the heat sink all falls on the projection of the light-emitting chip in the length direction of the heat sink.

[0012] In a possible implementation manner, a first axis of the light-emitting chip coincides with a second axis of the protection device.

[0013] In a possible implementation, the heat sink includes a heat sink substrate, a gold layer, and a gold-tin layer arranged in sequence;

[0014] The width of the gold-tin layer is smaller than the width of the gold layer, and the width of the gold layer is smaller than the width of the heat sink substrate;

[0015] The light emitting chip and the protection device are welded on the gold-tin layer.

[0016] In a possible implementation manner, a distance between a first axis of the light-emitting chip and a second axis of the protection device along a width direction of the heat sink is 0-0.35 mm.

[0017] In a possible implementation, the gold-tin layer is an integrated gold-tin layer.

[0018] In a possible implementation, when the gold-tin layer is eutectic, the light-emitting chip and the protection device are both located on the integrated gold-tin layer.

[0019] In a possible implementation, the gold-tin layer is in a long strip shape and extends along the length direction of the heat sink;

[0020] The light emitting chip and the protection device are arranged in sequence along the length direction of the gold-tin layer.

[0021] In a possible implementation, it is characterized in that the gold-tin layer is L-shaped, and the gold-tin layer includes a first area and a second area, the first area is in a long strip shape and extends along the length direction of the heat sink, and the second area is located on one side of the first area;

[0022] The light emitting chip is located in the first area, a portion of the protection device is located in the second area, and another portion of the protection device is located in the first area.

[0023] In a possible implementation, the gold-tin layer includes a first gold-tin layer and a second gold-tin layer separated from each other, the first gold-tin layer and the second gold-tin layer are spaced apart in the length direction of the heat sink, and projections of the first gold-tin layer and the second gold-tin layer along the length direction of the heat sink at least partially overlap.

[0024] The light emitting chip is located in the first gold-tin layer, and the protection device is located in the second gold-tin layer.

[0025] In a possible implementation manner, the widths of the gold layers on both sides of the light-emitting chip are equal.

[0026] In a possible implementation, the width of the gold layer on both sides of the gold-tin layer is 0.2 mm-0.4 mm.

[0027] In a possible implementation, the width of the gold layer on both sides of the gold-tin layer is 0.2 mm.

[0028] In a possible implementation, when the gold-tin layer is in the shape of an elongated strip, the axis of the gold layer along the length direction of the heat sink coincides with the axis of the gold-tin layer along the length direction of the heat sink.

[0029] In a possible implementation, the light emitting device includes a plurality of the heat sinks, a plurality of the light emitting chips, and a plurality of the protection devices, and the number of the heat sinks, the light emitting chips, and the protection devices is equal;

[0030] The light emitting chip on the first heat sink is connected to the gold layer of the second heat sink via a gold wire;

[0031] The protection device located on the first heat sink is connected to the gold layer of the second heat sink through a gold wire;

[0032] Wherein, the first heat sink and the second heat sink are two adjacent heat sinks.

[0033] In a possible implementation, the number of the heat sinks is 16-36.

[0034] In a possible implementation, the light emitting device further includes a cover plate and a lens assembly, and the frame, the cover plate and the lens assembly are arranged in sequence;

[0035] The lens assembly includes a plurality of lenses, and the number of the lenses is the same as the number of the light-emitting chips. The lenses are used to converge the lasers emitted by the light-emitting chips.

[0036] The technical solution provided by the present disclosure includes at least the following beneficial effects:

[0037] The present disclosure provides a light-emitting device, in which a light-emitting chip and a protective device have a spacing in the length direction of a heat sink, so that the light-emitting chip and the protective device are not arranged side by side in the width direction, and there is no need for a safety distance between the light-emitting chip and the protective device. Furthermore, the size occupied by the light-emitting chip and the protective device in the width direction can be reduced, thereby reducing the width of the light-emitting device, thereby realizing miniaturization of the light-emitting device.

[0038] It is to be understood that the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the present disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] The accompanying drawings herein are incorporated in and constitute a part of the specification, illustrate embodiments consistent with the present disclosure, and together with the description, are used to explain the principles of the present disclosure. In the drawings:

[0040] Figure 1 is a schematic structural diagram of a light-emitting device in a related technology shown in an embodiment of the present disclosure;

[0041] Figure 2 is a schematic structural diagram of a light-emitting device in a related technology shown in an embodiment of the present disclosure;

[0042] Figure 3 is a structural schematic diagram of a light-emitting device shown in an embodiment of the present disclosure;

[0043] Figure 4 is a partial structural schematic diagram of a light emitting device shown in an embodiment of the present disclosure;

[0044] Figure 5 is a partial structural schematic diagram of a light emitting device shown in an embodiment of the present disclosure;

[0045] Figure 6 is a partial structural schematic diagram of a light emitting device shown in an embodiment of the present disclosure;

[0046] Figure 7 is a cross-sectional schematic diagram of a light emitting device shown in an embodiment of the present disclosure;

[0047] Figure 8 is a partial structural schematic diagram of a light emitting device shown in an embodiment of the present disclosure;

[0048] Fig. 9 is a partial structural schematic diagram of a light emitting device shown in an embodiment of the present disclosure;

[0049] Fig.10 It is a schematic diagram showing the connection between an electric probe, a heat sink and a light-emitting chip in a related technology shown in an embodiment of the present disclosure;

[0050] Fig.11 is a schematic diagram showing a connection between an electrical probe, a heat sink, and a light-emitting chip shown in an embodiment of the present disclosure;

[0051] Fig.12 is a schematic diagram showing a connection between an electrical probe, a heat sink, and a light-emitting chip shown in an embodiment of the present disclosure;

[0052] Fig.13 is a partial structural schematic diagram of a light emitting device in a related technology shown in an embodiment of the present disclosure;

[0053] Fig.14 is a partial structural schematic diagram of a light emitting device shown in an embodiment of the present disclosure;

[0054] Fig.15 is a partial structural schematic diagram of a light emitting device shown in an embodiment of the present disclosure;

[0055] Fig.16is a partial structural schematic diagram of a light emitting device in a related technology shown in an embodiment of the present disclosure;

[0056] Fig.17 It is a schematic diagram of a partial structure of a light-emitting device shown in an embodiment of the present disclosure.

[0057] Legend

[0058] 1. Frame;

[0059] 2. Substrate;

[0060] 3. heat sink, 31. heat sink substrate, 32. gold layer, 33. gold-tin layer, 331. first region, 332. second region, 33a. first gold-tin layer, 33b. second gold-tin layer;

[0061] 4. Light-emitting chip;

[0062] 5. Protective devices;

[0063] 6. Glue;

[0064] 7. Electrical probe;

[0065] 8. Gold thread;

[0066] 9. Soldering points;

[0067] 10. A first electrical connection component;

[0068] 11. A second electrical connection component;

[0069] 12. Cover plate;

[0070] 13. Lens assembly;

[0071] A, first axis, B, second axis, X, width direction, Y, length direction, a, safety distance.

[0072] The above drawings show clear embodiments of the present disclosure, which will be described in more detail below. These drawings and text descriptions are not intended to limit the scope of the present disclosure in any way, but to illustrate the concepts of the present disclosure to those skilled in the art by referring to specific embodiments. DETAILED DESCRIPTION

[0073] In order to make the objectives, technical solutions and advantages of the present disclosure more clear, the embodiments of the present disclosure will be further described in detail below with reference to the accompanying drawings.

[0074] The terms used in the embodiments of the present disclosure are only used to explain the embodiments of the present disclosure, and are not intended to limit the present disclosure. Unless otherwise defined, the technical terms or scientific terms used herein should be understood by people with ordinary skills in the field to which the present disclosure belongs. The words "first", "second", "third" and similar words used in the patent application specification and claims of the present disclosure do not indicate any order, quantity or importance, but are only used to distinguish different components. Similarly, words such as "one" or "one" do not indicate a quantity limit, but indicate that there is at least one. Words such as "include" or "include" mean that the elements or objects appearing in front of "include" or "include" include the elements or objects listed after "include" or "include" and their equivalents, and do not exclude other elements or objects. Words such as "connect" or "connected" are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. "Up", "down", "left", "right" and the like are only used to indicate relative positional relationships. When the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0075] In recent years, the miniaturization and portability of electronic devices has become a major trend. In the display product industry, traditional LCD TVs are no longer the first choice for consumers to buy TVs due to their large size and heavy weight. Gradually, small-sized and lightweight display products such as micro-projectors have become popular among the public. Driven by this major trend, light-emitting devices, as the core components of display products, are naturally also gradually developing towards miniaturization.

[0076] The light emitting device comprises a frame 1, a substrate 2, a heat sink 3, a light emitting chip 4 and a protective device 5. The frame 1 and the heat sink 3 are fixed on the substrate 2, and the heat sink 3 is located inside the frame 1, and the light emitting chip 4 and the protective device 5 are located on the heat sink 3. The light emitting device comprises a plurality of heat sinks 3, and each heat sink 3 has a light emitting chip 4 and a protective device 5.

[0077] In order to achieve miniaturization of the light-emitting device, it is necessary to mount the same or even more light-emitting chips 4 (heat sinks 3) in the frame 1 of a smaller light-emitting device, that is, to achieve a dense arrangement of the light-emitting chips 4 in the frame 1, which means that the distance L between two adjacent light-emitting chips 4 needs to be reduced. Figure 1 As shown, the distance L between two adjacent light emitting chips 4 is affected by the width of the light emitting chip 4 , the width of the heat sink 3 , and the overflow size of the glue 6 used for mounting the heat sink 3 .

[0078] At present, on the one hand, due to technical problems, the size of the light-emitting chip 4 cannot be reduced temporarily. On the other hand, due to equipment capabilities and reliability requirements, the overflow size of the glue 6 cannot be further reduced, otherwise it is easy to cause the heat sink 3 to fall off. Therefore, how to reduce the width of the heat sink 3 has become the key to solving the problem of miniaturization of light-emitting devices.

[0079] In addition, since the antistatic capability of the light emitting chip 4 is relatively weak, a protection device 5 needs to be placed on the heat sink 3 in parallel with the light emitting chip 4 to protect the light emitting chip 4 .

[0080] In related technologies, such as Figure 2 As shown, the protection device 5 is welded on the heat sink 3, and the light emitting chip 4 and the protection device 5 are arranged side by side along the width direction X of the heat sink 3. Since there is a certain error when the equipment places the light emitting chip 4 and the protection device 5, in order to avoid the collision between the light emitting chip 4 and the protection device 5, a certain safety distance a needs to be left between the light emitting chip 4 and the protection device 5, which makes the size occupied by the light emitting chip 4 and the protection device 5 in the width direction m+a+n, resulting in a larger width of the heat sink 3. In this case, it is difficult to further reduce the size of the heat sink 3.

[0081] In view of the above technical problems, the present disclosure provides a light emitting device, such as Figure 3 and Figure 4 As shown, the light emitting device includes a frame 1, a substrate 2, a heat sink 3, a light emitting chip 4 and a protective device 5. The frame 1 and the heat sink 3 are both fixed to the substrate 1, and the heat sink 3, the light emitting chip 4 and the protective device 5 are all located inside the frame 1. The light emitting chip 4 and the protective device 5 are fixed to the heat sink 3, and the light emitting chip 4 and the protective device 5 have a spacing in the length direction Y of the heat sink 3.

[0082] Among them, the light-emitting device can also be called a laser.

[0083] The component composed of the heat sink 3, the light emitting chip 4 and the protection device 5 can be called a COS (Chip On Submount, embedded chip).

[0084] The light emitting chip 4 may also be called a blue-green chip. The width of the light emitting chip 4 may be 0.1 mm-0.3 mm. For example, the width of the light emitting chip 4 is 0.2 mm. The light emitting point of the light emitting chip 4 is located at one end of the light emitting chip 4 away from the protective device 5. The end where the light emitting point is located may be called the front end of the light emitting chip 4, and the end close to the protective device 5 may be called the rear end of the light emitting chip 4. The light emitting chip 4 emits a large amount of heat when working, and the heat sink 3 is used to absorb the heat emitted by the light emitting chip 4.

[0085] The protection device 5 can also be called a protection element. The protection device 5 can be a Zener diode or a voltage regulator. The width of the protection device 5 can be 0.2-0.4 mm. For example, the width of the protection device 5 can be 0.3 mm. The protection device 5 is connected in parallel with the light emitting chip 4 to improve the antistatic ability of the light emitting chip 4.

[0086] The light-emitting device provided in the embodiment of the present disclosure is configured such that the light-emitting chip 4 and the protective device 5 have a spacing in the length direction of the heat sink 3, so that there is no need for a safety distance between the light-emitting chip 4 and the protective device 5 in the width direction. Thus, the size occupied by the light-emitting chip 4 and the protective device 5 in the width direction can be reduced, so that the width of the light-emitting device is reduced, which is conducive to the miniaturization of the light-emitting device.

[0087] In addition, it should be noted that since the length of the frame 1 of the light-emitting device is relatively long and the distance between two adjacent heat sinks 3 arranged along the length direction of the frame 1 of the light-emitting device is relatively long, compared with the light-emitting device in the related art, although the light-emitting chip 4 and the protective device 5 occupy a larger size in the length direction, the length of the frame 1 will not be increased, and the miniaturization of the light-emitting device will not be adversely affected.

[0088] The following is an exemplary description of the arrangement of the light emitting chip 4 and the protection device 5:

[0089] In some examples, such as Figure 4 and Figure 5 As shown, the projections of the light emitting chip 4 and the protection device 5 in the length direction Y of the heat sink 3 at least partially overlap.

[0090] In some examples, such as Figure 5 As shown, assuming that the length of the overlapping portion of the projections of the light emitting chip 4 and the protection device 5 along the length direction Y of the heat sink 3 is c, the size occupied by the light emitting chip 4 and the protection device 5 in the width direction X of the heat sink 3 is m+nc.

[0091] Among them, c can also be 0, in which case the side edge of the light emitting chip 4 and the side edge of the protection device 5 coincide with each other.

[0092] In order to further reduce the size of the light emitting chip 4 and the protection device 5 in the width direction X, in some examples, such as Figure 4 As shown, the projection of the light emitting chip 4 in the length direction Y of the heat sink 3 all falls on the projection of the protection device 5 along the length direction Y of the heat sink 3 . The width m of the light emitting chip 4 is smaller than the width n of the protection device 5 .

[0093] In this way, the dimension occupied by the light emitting chip 4 and the protection device 5 in the width direction X of the heat sink 3 is the width n of the protection device 5 .

[0094] In other examples, the projection of the protection device 5 in the length direction Y of the heat sink 3 may all fall on the projection of the light emitting chip 4 in the length direction Y of the heat sink 3 . The width m of the light emitting chip 4 is greater than the width n of the protection device 5 .

[0095] In this way, the dimension occupied by the light emitting chip 4 and the protection device 5 in the width direction X of the heat sink 3 is the width m of the light emitting chip 4 .

[0096] In both of the above cases, the size occupied by the light emitting chip 4 and the protection device 5 in the width direction X can be minimized, and the width of the light emitting device can be minimized.

[0097] In some examples, such as Figure 4 As shown, the symmetry axis of the light emitting chip 4 and the symmetry axis of the protection device 5 coincide with each other.

[0098] In some examples, the distance between the first axis A of the light emitting chip 4 and the second axis B of the protection device 5 in the width direction X of the heat sink 3 is 0-0.35 mm.

[0099] According to actual measurements, when the distance between the first axis A and the second axis B is 0-0.35 mm, the size occupied by the light emitting chip 4 and the protection device 5 in the width direction X of the heat sink 3 is smaller than that occupied by the existing solution.

[0100] In other examples, such as Figure 6 As shown, the projections of the light emitting chip 4 and the protection device 5 in the length direction Y of the heat sink 3 may not overlap. For example, the spacing in the width direction is b.

[0101] In this case, since there is no need for a safety distance between the light emitting chip 4 and the protection device 5 in the width direction X, b can be smaller than the safety distance a in the related art, thereby still being able to achieve the purpose of reducing the width of the heat sink 3. Among them, b can be as small as 0.

[0102] In some examples, such as Figure 7 As shown, the heat sink 3 includes a heat sink substrate 31, a gold layer 32 and a gold-tin layer 33 arranged in sequence, the width of the gold-tin layer 33 is smaller than the width of the gold layer 32, the width of the gold layer 32 is smaller than the width of the heat sink substrate 31, and the light-emitting chip 4 and the protective device 4 are welded on the gold-tin layer 33.

[0103] The structure of the gold-tin layer 33 is related to the arrangement of the light-emitting chip 4 and the protective device 5. The following is an exemplary description of the implementation of the gold-tin layer 33 in combination with the arrangement of the light-emitting chip 4 and the protective device 5:

[0104] In some examples, such as Figure 4 and Figure 5 As shown, the gold-tin layer 33 is an integrated gold-tin layer.

[0105] In this case, when the light-emitting chip 4 and the protective device 5 are welded on the heat sink 3, the gold-tin layer 33 only needs to be eutectic once, and then the light-emitting chip 4 and the protective device 5 can be welded on the gold-tin layer 33, thereby saving the eutectic time and improving the preparation efficiency of the light-emitting device.

[0106] In some examples, such as Figure 4 As shown, the AuSn layer 33 is in a long strip shape and extends along the length direction Y of the heat sink 3 , and the light emitting chip 4 and the protection device 5 are arranged in sequence along the length direction of the AuSn layer 33 .

[0107] In some examples, such as Figure 5 As shown, the gold-tin layer 33 is L-shaped, and includes a first region 331 and a second region 332. The first region 331 is in a long strip shape and extends along the length direction of the heat sink 3, and the second region 332 is located on one side of the first region 331. The light-emitting chip 4 is located in the first region 331, and a part of the protection device 5 is located in the second region 332, and the other part is located in the first region 331.

[0108] Of course, in other examples, the gold-tin layer 33 may be in other shapes, as long as the above arrangement of the light-emitting chip 4 and the protection device 5 can still be achieved, and the embodiments of the present disclosure do not specifically limit this.

[0109] In other examples, such as Figure 8 As shown, the gold-tin layer 33 includes a separated first gold-tin layer 33a and a second gold-tin layer 33b, the first gold-tin layer 33a and the second gold-tin layer 33b have a spacing in the length direction Y of the heat sink 3, the light-emitting chip 4 is located in the first gold-tin layer 33a, and the protection device 5 is located in the second gold-tin layer 33b.

[0110] The projections of the first gold-tin layer 33 a and the second gold-tin layer 33 b in the length direction Y of the heat sink 3 at least partially overlap.

[0111] In some examples, such as Figure 8 As shown, the second gold-tin layer 33 b is located on one side of the first gold-tin layer 33 a , and the projections of the first gold-tin layer 33 a and the second gold-tin layer 33 b in the length direction Y of the heat sink 3 partially overlap.

[0112] In other examples, such as Fig. 9 As shown, the projections of the first AuSn layer 33a and the second AuSn layer 33b along the length direction Y of the heat sink 3 completely overlap. At this time, the first axis A of the light emitting chip 4 and the second axis B of the protection device 5 may overlap.

[0113] After the eutectic of the light-emitting chip 4, the protective device 5 and the gold-tin layer 33 is completed, an aging test is required for the light-emitting device. When performing the aging test on the light-emitting device, the light-emitting device needs to be placed on a heat dissipation base plate, and the gold layer 32, the light-emitting chip 4 and the heat dissipation base plate are connected using an electrical probe 7. After the aging test is completed, the electrical probe 7 on the gold layer 32 and the light-emitting chip 4 is removed.

[0114] In related technologies, such as Fig.10 As shown, assuming that the second gold-tin layer 33b is located on the right side of the first gold-tin layer 33a, since there is a gap between the first gold-tin layer 33a where the light-emitting chip 4 is located and the second gold-tin layer 33b where the protection device 5 is located, the area of ​​the gold layer 32 on the right side of the first gold-tin layer 33a will be larger than the area of ​​the gold layer 32 on the left side of the first gold-tin layer 33a, and at the same time, the position of the light-emitting chip 4 will be offset to the left relative to the axis of the heat sink 3, resulting in uneven distribution of the electrical probe 7 relative to the light-emitting chip 4.

[0115] In this way, on the one hand, since the electric probe 7 is inserted into the gold layer 32, a pulling force is generated on the gold layer 32, which in turn causes uneven force on the gold layer 32 on the left side of the light-emitting chip 4 and the gold layer 32 on the right side of the light-emitting chip 4. Since the light-emitting chip 4 is soldered to the first gold-tin layer 33a on the gold layer 32, the uneven force on the gold layer 32 also causes uneven pulling force on the light-emitting chip 4, making the pulling force on the left side of the light-emitting chip 4 greater than the pulling force on the right side of the light-emitting chip 4, thereby increasing the risk of damage to the light-emitting chip 4.

[0116] On the other hand, due to the wide width of the light-emitting device, it is easy for the area of ​​the gold layer 32 that is not connected to the electrical probe 7 to not fully contact the heat dissipation base plate, especially the gold layer 32 on the right side of the light-emitting chip 4 is difficult to fully contact the heat dissipation base plate, thereby affecting the heat dissipation effect of the light-emitting device and causing the light-emitting device to be easily damaged.

[0117] Since in the light-emitting device provided by the embodiment of the present disclosure, the projections of the light-emitting chip 4 and the protection device 5 along the length direction Y of the heat sink 3 at least partially overlap, the width of the area occupied by the gold-tin layer 33 is narrow, thereby reducing the difference in tension on both sides of the light-emitting chip 4.

[0118] Further, in order, in some examples, such as Fig.11 and Fig.12 As shown, the widths of the gold layer 32 on both sides of the gold-tin layer 33 are equal.

[0119] In this way, when the aging test is performed on the light-emitting device, on the one hand, the distribution of the electric probe 7 on the gold layer 32 on the left and right sides of the light-emitting chip 4 can be made more uniform, so that the force on the gold layer 32 can be more uniform, and then the tension on the left and right sides of the light-emitting chip 4 can be made more uniform, so that the light-emitting chip 4 is not easily damaged.

[0120] On the other hand, since the width of the AuSn layer 33 is small at this time, that is, the width of the heat sink 3 is small, the heat sink 3 can fully contact with the heat dissipation base plate, which is beneficial to the heat dissipation of the light emitting device.

[0121] In some examples, the width of the gold layer 32 on both sides of the light emitting chip 4 may be 0.2 mm-0.4 mm.

[0122] Exemplarily, the width of the gold layer 32 on both sides of the gold-tin layer 33 may be 0.2 mm.

[0123] It should be noted that the width of the gold layer 32 cannot be too small. On the one hand, the width of the gold layer 32 on both sides of the gold-tin layer 33 must be at least larger than the width of the electrical probe 7 to ensure that the electrical probe 7 can be connected to the gold layer 32 .

[0124] On the other hand, if the width of the gold layer 32 is too small, the heat dissipation effect of the heat sink 3 will be affected, which is not conducive to the heat dissipation of the light emitting chip 4, thereby causing the light emitting chip 4 to be easily damaged.

[0125] In some instances, such as Fig.12 As shown, the lengths of the gold layers 32 on both sides of the light emitting chip 4 may also be the same.

[0126] In some instances, such as Figure 3 As shown, the light emitting device includes a plurality of heat sinks 3, a plurality of light emitting chips 4 and a plurality of protection devices 5, and the number of heat sinks 3, light emitting chips 4 and protection devices 5 is equal. Fig.14 As shown, the light emitting chip 4 on the first heat sink is connected to the gold layer 32 of the second heat sink via gold wire 8, and the protection device 5 on the first heat sink is connected to the gold layer 32 of the second heat sink via gold wire 8. The first heat sink and the second heat sink are two adjacent heat sinks 3.

[0127] The heat sinks 3 are arranged in an array on the substrate 2, and the width direction of the heat sinks 3 is consistent with the width direction of the substrate 2. The heat sinks 3 in each row are arranged along the width direction of the substrate 2, and the light-emitting chips 3 on each row of the heat sinks 3 are connected in series.

[0128] Since the light-emitting device has a plurality of evenly arranged light-emitting chips 4 (heat sinks 3), after the light-emitting device is prepared, it is necessary to electrically connect the adjacent light-emitting chips 4 (heat sinks 3) so that the adjacent light-emitting chips 4 are connected in series. Two adjacent light-emitting chips 4 need to be electrically connected via a gold wire 8, and both ends of each gold wire 8 are welded to the heat sink 3, the light-emitting chip 4 or the protective device 5 via solder joints 9. Since the current passing between the two adjacent light-emitting chips 4 is relatively large after the two adjacent light-emitting chips 4 are electrically connected, and the wire diameter of the gold wire 8 is relatively small, the maximum current that the gold wire 8 can withstand is also relatively small. Therefore, in order to avoid the circuit being too large and the gold wire 8 being melted, three gold wires 8 are usually used to electrically connect the two adjacent light-emitting chips 4. In this way, the current passing through each gold wire 8 will be reduced, so that the gold wire 8 is not easily melted.

[0129] like Fig.13 As shown, in the related art, the light-emitting chip 4 is electrically connected to the gold layer 32 on the adjacent heat sink 3 through three gold wires 8. Since the gold layer 32 and the first gold-tin layer 33a are both metal layers, the gold layer 32 and the first gold-tin layer 33a are conductive, so that the current can flow through the light-emitting chip 4 and then pass through the first gold-tin layer 33a and the gold layer 32 in sequence, and then flow through the light-emitting chip 4 on the adjacent light-emitting device, thereby realizing the series connection between the two adjacent light-emitting chips 4.

[0130] In order to improve the antistatic ability of the light emitting chip 4, the light emitting chip 4 is usually connected in parallel with the protective device 5. In the related art, the light emitting chip 4 and the protective device 5 are electrically connected through a gold wire 8, and the light emitting chip 4 and the protective device 5 have corresponding solder joints 9. The surface of the light emitting chip 4 has a metal layer, so after each gold wire 8 is energized, part of the current flows through the inside of the light emitting chip 4, and the other part of the current flows through the surface of the light emitting chip 4 and the protective device 5, thereby realizing the parallel connection of the light emitting chip 4 and the protective device 5. As can be seen from the above, the surface of the light emitting chip 4 in the related art has four solder joints 9. Among them, the solder joints 9 can also be called solder balls.

[0131] In the light-emitting device provided in the embodiment of the present disclosure, since the arrangement of the light-emitting chip 4 and the protection device 5 is different from that in the related art, the electrical connection method is also adjusted accordingly.

[0132] like Fig.14 and Fig.15 As shown, the light emitting chip 4 is electrically connected to the gold layer 32 on the adjacent heat sink 3 through three gold wires 8, and the light emitting chip 4 and the gold layer 32 have corresponding solder joints 9. Since the gold layer 32 is not easily damaged by welding, the protection device 5 is electrically connected to the gold layer 32 on the adjacent light emitting device through a gold wire 8, and the protection device 5 and the gold layer 32 have corresponding solder joints 9.

[0133] It can be seen that the surface of the light emitting chip 4 in the light emitting device provided in the embodiment of the present disclosure has three solder joints, wherein the solder joints 9 on the light emitting chip 4 and the solder joints 9 on the gold layer 32 are evenly arranged.

[0134] Among them, the gold layer 32 and the gold-tin layer 33 are both conductive materials, so the light-emitting chip 4 is electrically connected to the gold layer 32 on the adjacent light-emitting device through the gold wire 8, so that the light-emitting chip 4 can be electrically connected to the light-emitting chip 4 on the adjacent light-emitting device, thereby realizing the series connection between multiple light-emitting chips 4. After each gold wire 8 is energized, part of the current flows through the inside of the light-emitting chip 4, and the other part of the current no longer passes through the surface of the light-emitting chip 4 but directly passes through the protective device 5, thereby realizing the parallel connection between the light-emitting chip 4 and the protective device, thereby improving the antistatic ability of the light-emitting chip 4.

[0135] Compared with the related art, in the light-emitting device provided by the embodiment of the present disclosure, there are fewer solder joints 9 on the surface of the light-emitting chip 4, so the damage to the light-emitting chip 4 during the soldering process can be reduced.

[0136] In addition, after the number of solder joints 9 on the surface of the light-emitting chip 4 is reduced, the three solder joints 9 can be moved as a whole toward the rear end of the light-emitting chip 4, so that the solder joints 9 are away from the front end of the light-emitting chip 4, that is, the solder joints 9 are away from the light-emitting points of the light-emitting chip 4, thereby reducing the risk of the solder joints 9 causing damage to the light-emitting points of the light-emitting chip 4.

[0137] It should be noted that Fig.16 In the technical solution of the related art shown, even if the gold wire 8 between the light emitting chip 4 and the protective device 5 is changed to the gold wire 8 between the protective device 5 and the gold layer 32, since the light emitting chip 4 and the protective device 5 are arranged in parallel, the gold wire 8 will hinder the other three gold wires 8 from moving toward the rear end of the light emitting chip 4, so that the light emitting point of the light emitting chip 4 will still be greatly affected by the soldering point 9. If only the soldering point 9 on the light emitting chip 4 is moved toward the rear end of the light emitting chip 4, the corresponding three gold wires 8 will be tilted, and the gold wire 8 close to the protective device 5 may cross and collide with the gold wire 8 between the protective device 5 and the gold layer 32. Therefore, in the related art, it is not feasible to only move the soldering point 9 on the light emitting chip 4 toward the rear end of the light emitting chip 4.

[0138] The assembly consisting of the heat sink 3, the light emitting chip 4 and the protection device 5 can be called a COS. Fig.17As shown, after multiple COS are connected in series, the two COS located at the two ends are electrically connected to the first electrical connector 10 and the second electrical connector 11 respectively. The first electrical connector 10 and the second electrical connector 11 are both electrically connected to the substrate 2. The substrate 2 has a driving circuit. The driving circuit can send an electrical signal to the light-emitting chip 4 through the first electrical connector 10 or the second electrical connector 11, thereby driving the light-emitting chip 4 to emit laser. Among them, the first electrical connector 10 and the second electrical connector 11 can be PIN pins.

[0139] Assuming that the driving circuit sends an electrical signal to the COS through the first electrical connector 10, a part of the current conducted by the first electrical connector 10 flows through the light-emitting chip 4, and another part flows through the protective device 5, and then merges on the gold layer 32. The current on the gold layer 32 then enters the next COS, and a part of it flows through the light-emitting chip 4, and another part flows through the protective device 5, and then flows through the second electrical connector 11.

[0140] In some examples, the number of heat sinks 3 (COS) may be 16-36.

[0141] For example, the number of heat sinks 3 (COS) can be 20, and the multiple heat sinks 3 (COS) can be evenly distributed in four rows and five columns. The (COS) in each row are connected in series, and the COS at both ends of each row of COS are electrically connected to the first electrical connector 10 and the second electrical connector 11 respectively.

[0142] In some examples, such as Figure 3 As shown, the light emitting device further includes a cover plate 12 and a lens assembly 13. The frame 1, the cover plate 12 and the lens assembly 13 are arranged in sequence. The lens assembly 13 includes a plurality of lenses, and the number of lenses is the same as the number of light emitting chips 4. The lenses are used to converge the laser emitted by the light emitting chips 4.

[0143] The above description is only an optional embodiment of the present disclosure and is not intended to limit the present disclosure. Any modifications, equivalent substitutions, improvements, etc. made within the principles of the present disclosure shall be included in the protection scope of the present disclosure.

Claims

1. A light emitting device, characterized in that: The light emitting device comprises a frame, a substrate, a heat sink, a light emitting chip and a protective device; The frame and the heat sink are both fixed on the substrate, and the heat sink, the light emitting chip and the protection device are all located inside the frame; The light emitting chip and the protection device are both fixed on the heat sink, and there is a distance between the light emitting chip and the protection device in the length direction of the heat sink.

2. The light emitting device according to claim 1, characterized in that: The projections of the light emitting chip and the protection device in the length direction of the heat sink at least partially overlap.

3. The light emitting device according to claim 2, characterized in that: The projections of the light-emitting chip in the length direction of the heat sink all fall on the projection of the protection device in the length direction of the heat sink; or, The projection of the protection device in the length direction of the heat sink all falls on the projection of the light emitting chip in the length direction of the heat sink.

4. The light emitting device according to claim 3, characterized in that: The first axis of the light emitting chip coincides with the second axis of the protection device.

5. The light emitting device according to any one of claims 1 to 4, characterized in that: The heat sink comprises a gold-tin layer, a gold layer and a heat sink substrate arranged in sequence from top to bottom; The width of the gold-tin layer is smaller than the width of the gold layer, and the width of the gold layer is smaller than the width of the heat sink substrate; The light emitting chip and the protection device are both smaller than the width of the gold-tin layer, and the light emitting chip and the protection device are welded on the gold-tin layer.

6. The light emitting device according to claim 5, characterized in that: The gold-tin layer is an integrated gold-tin layer.

7. The light emitting device according to claim 6, characterized in that: The gold-tin layer is in a long strip shape and extends along the length direction of the heat sink; The light emitting chip and the protection device are arranged in sequence along the length direction of the gold-tin layer.

8. The light emitting device according to claim 6, characterized in that: The gold-tin layer is L-shaped, and includes a first region and a second region, the first region is in a strip shape and extends along the length direction of the heat sink, and the second region is located on one side of the first region; The light emitting chip is located in the first area, a portion of the protection device is located in the second area, and another portion of the protection device is located in the first area.

9. The light emitting device according to claim 5, characterized in that: The gold-tin layer comprises a first gold-tin layer and a second gold-tin layer separated from each other, wherein the first gold-tin layer and the second gold-tin layer are spaced apart in the length direction of the heat sink, and projections of the first gold-tin layer and the second gold-tin layer in the length direction of the heat sink at least partially overlap; The light emitting chip is located in the first gold-tin layer, and the protection device is located in the second gold-tin layer.

10. The light emitting device according to claim 5, characterized in that: The widths of the gold layers on both sides of the light-emitting chip are equal.

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