Optical coupler

Abstract

The utility model relates to the technical field of optical couplers, in particular to an optical coupler. The phototriode and the light-emitting diode are respectively fixed by arranging the two groups of supporting leg assemblies, so that the phototriode and the light-emitting diode are distributed in the colloid in a diagonal manner, and more light rays emitted by the light-emitting diode can directly irradiate into the phototriode, so that the light receiving efficiency of the optical coupler is improved; by arranging the isolation gap and limiting the relative positions of the two groups of supporting leg assemblies, on one hand, the processing yield in the whole processing process is ensured, the occurrence of adverse conditions such as interference and wire breakage is reduced, on the other hand, the light receiving efficiency of the optical coupler can be ensured, and the CTR value of the optical coupler is stabilized to be 450 or above; the planar optical coupler solves the problems that the existing planar optical coupler is low in light receiving efficiency and low in CTR during working, and a high-HFE triode needs to be used, so that the Switch time is long.

Description

Technical Field

[0001] The utility model relates to the technical field of optical couplers, in particular to an optical coupler. Background Art

[0002] When the planar optical coupler transmits optical signals, the infrared diode emits light after being powered on, and then the light emitted by the light-emitting diode is reflected to the phototransistor mainly through the reflective structure set in the colloid. When the phototransistor is exposed to a certain degree of light, it will generate a stable current to achieve electrical-optical-electrical conversion. It has a good isolation effect on input and output electrical signals, so it is widely used in various circuits.

[0003] When the current planar optical coupler is working, the light emitting diode and the phototransistor are located on the same plane. In order to ensure the intensity of the light irradiated on the surface of the phototransistor, a special reflective structure needs to be set in the colloid to reflect more light to the phototransistor. Therefore, the light emitted by the light emitting diode needs to pass through a layer of plastic-sealed milky white epoxy resin and be reflected to the light receiving area of ​​the transistor by a second layer of plastic-sealed carbon black epoxy resin. Since the reflectivity of the second layer of plastic-sealed epoxy resin is about 70%, 30% of the radiant light flux will be lost. At the same time, since it is reflected light, a lot of light cannot be received by the transistor, and its light receiving efficiency is still low. Even if a high HFE (magnification) transistor is used, the CTR is difficult to reach more than 450. At the same time, due to the use of high HFE transistors, its optical coupler switching time is long, and the limited field frequency recognition at the application end is low. Utility Model Content

[0004] In view of the shortcomings of the prior art, the utility model provides an optical coupler, which solves the problems of low light receiving efficiency and low CTR of the current planar optical coupler during operation, and the need to use a high HFE triode resulting in a long switching time.

[0005] In order to achieve the above purpose, the utility model provides the following technical solutions:

[0006] An optical coupler includes a phototransistor and a light emitting diode for optical signal transmission, two groups of leg assemblies for mounting the phototransistor and the light emitting diode respectively, and a colloid for encapsulating the phototransistor, the light emitting diode and the leg assemblies;

[0007] The support leg assembly includes a first mounting portion arranged in the colloid for mounting a phototransistor or a light-emitting diode, and a second mounting portion connected to the phototransistor or the light-emitting diode through a wire, the first mounting portion and the second mounting portion are both provided with pins that penetrate to the outside of the colloid, and the projection of one group of the first mounting portion and the second mounting portion on the plane where the other group of the first mounting portion and the second mounting portion are located is offset from the other group of the first mounting portion and the second mounting portion.

[0008] Preferably, the shortest distance between the first mounting portions of the two groups of the support leg assemblies is 0.8 mm to 1.7 mm.

[0009] Preferably, a strip-shaped isolation gap is provided between a projection of one group of first mounting parts and second mounting parts on the plane where another group of first mounting parts and second mounting parts are located and another group of first mounting parts and second mounting parts.

[0010] Preferably, the width of the isolation gap is 0.05 mm to 0.2 mm.

[0011] Preferably, a first avoidance groove is provided on the first mounting portion for avoiding the second mounting portion on the same group of support leg assemblies.

[0012] Preferably, a second avoidance groove for avoiding another group of leg assemblies is provided on the pin connected to the second mounting portion.

[0013] Compared with the prior art, the utility model provides an optical coupler with the following beneficial effects:

[0014] 1. By setting two sets of support leg assemblies to fix the phototransistor and the light-emitting diode respectively, the phototransistor and the light-emitting diode are distributed diagonally in the colloid, so that the light emitted by the light-emitting diode can be more directly irradiated into the phototransistor, so as to improve the light receiving efficiency of the optical coupler, thereby improving its CTR value and stabilizing it to more than 450. At the same time, it can also save the reflective structure design in the traditional planar optical coupler, which is more convenient.

[0015] 2. By setting the isolation gap and limiting the relative positions of the two sets of support leg assemblies, the processing yield can be guaranteed during the overall processing and the occurrence of adverse conditions such as interference and wire breakage can be reduced. On the other hand, the light collection efficiency of the optical coupler can be guaranteed and its CTR value can be stabilized to above 450. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The drawings described herein are used to provide a further understanding of the present application and constitute a part of the present application. The illustrative embodiments of the present application and their descriptions are used to explain the present application and do not constitute an improper limitation on the present application. In the drawings:

[0017] Figure 1 It is a front view of the optical coupler of the utility model;

[0018] Figure 2 It is a side view of the optical coupler of the utility model.

[0019] In the figure: 1. phototransistor; 2. light emitting diode; 3. support leg assembly; 31. first mounting portion; 32. second mounting portion; 33. pin; 34. isolation gap; 35. first avoidance groove; 36. second avoidance groove; 4. colloid. DETAILED DESCRIPTION

[0020] The following will describe the implementation methods of the present application in detail with the help of accompanying drawings and examples, so that the implementation process of how the present application uses technical means to solve technical problems and achieve technical effects can be fully understood and implemented accordingly.

[0021] In order to solve the problem that the current planar optical coupler has low light collection efficiency during operation and CTR is difficult to reach above 450, an optical coupler is proposed. Please refer to Figure 1-Figure 2 , by changing the structure of the current planar optical coupler to improve the light receiving efficiency and the CTR of the optical coupler, including a phototransistor 1 and a light emitting diode 2 for optical signal transmission, the light emitting diode 2 is used to emit light after being powered on, and the light is received by the phototransistor 1 and then generates an electrical signal, and two groups of support leg components 3 for mounting the phototransistor 1 and the light emitting diode 2 respectively, that is, one group of the support leg components 3 is used to mount the phototransistor 1, and the other group of the support leg components 3 is used to mount the light emitting diode 2, and a colloid 4 for encapsulating the phototransistor 1, the light emitting diode 2 and the support leg components 3, the colloid 4 plays a role in protecting the phototransistor 1 and the light emitting diode 2, and blocking external light from entering the interior thereof and affecting the optical signal transmission;

[0022] The support leg assembly 3 includes a first mounting portion 31 disposed in the colloid 4 for mounting the phototransistor 1 or the light-emitting diode 2, and a second mounting portion 32 connected to the phototransistor 1 or the light-emitting diode 2 through a wire, that is, the first mounting portion 31 and the second mounting portion 32 are respectively connected to the two electrodes of the phototransistor 1 or the light-emitting diode 2, and the first mounting portion 31 and the second mounting portion 32 are both provided with pins 33 that penetrate the outside of the colloid 4, and the pins 33 are used to be inserted into an external circuit board to realize the transmission of electrical signals, wherein one group of the first mounting portion 31 and the second mounting portion 32 are connected to the other group of the first mounting portion 31 and the second mounting portion 32. The projection of the mounting portion 32 on the plane is offset from another group of first mounting portions 31 and second mounting portions 32, so that the phototransistor 1 or the light-emitting diode 2 is arranged diagonally in the colloid 4. At this time, a large amount of light transmitted by the light-emitting diode 2 will directly hit the phototransistor 1, so there is no need for a light reflection structure, which greatly reduces the light loss caused. The light collection efficiency is 40% better than that of the traditional planar reflective optical coupler. The light collection efficiency is higher, which meets the requirement of CTR value reaching more than 450, and it is no longer necessary to use a high HFE (magnification factor) transistor to make the CTR reach more than 450, so as to improve the recognition of the optical coupler at the application end.

[0023] If the phototransistor 1 or the light-emitting diode 2 is too close, it may cause interference during wire welding, and if it is too far, it may increase light loss, making it difficult for the CTR value to meet the requirements. Therefore, the shortest distance between the first mounting parts 31 of the two sets of leg assemblies 3 is set to 0.8mm~1.7mm. By adopting this distance requirement, the yield of the wire welding can be improved while ensuring the CTR value.

[0024] The optocoupler lead frames corresponding to the two groups of leg assemblies 3 may interfere with each other when overlapping, thereby causing assembly difficulties. Therefore, a strip-shaped isolation gap 34 is provided between the projection of one group of first mounting parts 31 and second mounting parts 32 on the plane where the other group of first mounting parts 31 and second mounting parts 32 are located and the other group of first mounting parts 31 and second mounting parts 32. The isolation gap 34 provides a distance between the two to ensure that there is no interference when assembling the optocoupler lead frames, thereby making the processing process smoother.

[0025] When the isolation gap 34 is too large, the distance between the phototransistor 1 or the light-emitting diode 2 may be too large, increasing light loss, making it difficult for the CTR value to meet the requirements. When the isolation gap 34 is too small, it may cause interference in the optocoupler lead frame. Therefore, the width of the isolation gap 34 is set to 0.05mm~0.2mm, which can not only ensure the smooth processing of the optocoupler, but also ensure that the CTR of the optocoupler is stable at above 450.

[0026] In order to ensure the overall structural size of the optical coupler and to ensure that the two groups of leg assemblies 3 are located on both sides of the isolation gap 34, a first avoidance groove 35 is provided on the first mounting portion 31 to avoid the second mounting portion 32 on the same group of leg assemblies 3, so as to avoid interference between the second mounting portion 32 and the first mounting portion 31 of the other group of leg assemblies 3.

[0027] When two optocoupler lead frames are superimposed so that the two leg assemblies 3 are located at corresponding positions, relevant parts on the two leg assemblies 3 may interfere with each other, so that the pins 33 connected to the second mounting portion 32 are provided with second avoidance grooves 36 for avoiding the other group of leg assemblies 3, thereby further avoiding interference between the pins 33 and the first mounting portion 31 of the other group of leg assemblies 3, which is beneficial to improving the smoothness and pass rate of the processing process.

[0028] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device.

[0029] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. An optical coupler, comprising a phototransistor (1) and a light emitting diode (2) for transmitting an optical signal, two groups of foot assemblies (3) for mounting the phototransistor (1) and the light emitting diode (2) respectively, and a colloid (4) for encapsulating the phototransistor (1), the light emitting diode (2) and the foot assemblies (3), characterized in that: The support leg assembly (3) comprises a first mounting portion (31) arranged in a colloid (4) for mounting a phototransistor (1) or a light-emitting diode (2), and a second mounting portion (32) connected to the phototransistor (1) or the light-emitting diode (2) via a wire, wherein the first mounting portion (31) and the second mounting portion (32) are both provided with pins (33) penetrating to the outside of the colloid (4), wherein a projection of one set of the first mounting portion (31) and the second mounting portion (32) on a plane where another set of the first mounting portion (31) and the second mounting portion (32) are located is arranged in a staggered manner with respect to the other set of the first mounting portion (31) and the second mounting portion (32).

2. The optical coupler according to claim 1, characterized in that: The shortest distance between the first mounting parts (31) of the two groups of the support leg assemblies (3) is 0.8 mm to 1.7 mm.

3. The optical coupler according to claim 1, wherein: A strip-shaped isolation gap (34) is provided between a projection of one group of first mounting parts (31) and second mounting parts (32) on a plane where another group of first mounting parts (31) and second mounting parts (32) are located and another group of first mounting parts (31) and second mounting parts (32).

4. The optical coupler according to claim 3, characterized in that: The width of the isolation gap (34) is 0.05 mm to 0.2 mm.

5. The optical coupler according to claim 1, wherein: The first mounting portion (31) is provided with a first avoidance groove (35) for avoiding the second mounting portion (32) on the same group of supporting leg components (3).

6. The optical coupler according to claim 1, wherein: A second avoidance groove (36) for avoiding another group of support leg assemblies (3) is provided on the pin (33) connected to the second mounting portion (32).

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