CN219393397U - Photoelectric coupler - Google Patents

Abstract

The utility model provides a photoelectric coupler, in particular to a semi-sealed photoelectric coupler. The photoelectric coupler comprises a substrate, a light emitter, a light receiver, a light guide layer and a light shielding layer, wherein the substrate is provided with a first surface and a second surface which are opposite, a plurality of metalized areas are arranged on the first surface, the metalized areas are used for being electrically connected with a circuit board, and the second surface is used for mounting the substrate on the circuit board; the light emitter and the light receiver are arranged on the first surface of the substrate and are respectively and electrically connected with the corresponding metallized areas; the light guide layer covers the first surface of the substrate and covers the light emitter and the light receiver; the shading layer covers the outer side of the light guide layer, and the light guide layer and the shading layer can realize optical coupling between the light emitter and the light receiver. According to the scheme, the substrate and the circuit board can be fixed in an adhesive mode, so that the limitation of adopting pin welding in the prior art is avoided.

Description

Photoelectric coupler

Technical Field

The utility model relates to the technical field of microelectronics, in particular to a photoelectric coupler, and especially relates to a semi-sealed photoelectric coupler.

Background

An Optical Coupler (Optical Coupler) is a device that transmits an electrical signal using light as a medium. The photoelectric coupler generally fixes the light emitter and the light receiver in the same package tube, when an electric signal is applied to the input end, the light emitter emits light, and the light receiver receives the light to generate photocurrent and outputs the photocurrent from the output end, so that the conversion of 'electricity-light-electricity' is realized. The photoelectric coupler has the characteristics of high anti-interference capability, long service life, high transmission efficiency and the like because of complete electrical isolation between input and output, and is one of the most widely applied photoelectric devices at present.

Currently, the optocoupler in the market mostly adopts fully sealed packages such as DIP packages (dual inline package, dual in-line packages) and SOP packages (small outline package, small outline packages), and typical examples are shown in fig. 1, in which the optoelectric element (including the light emitter 41 and the light receiver 42) is completely encapsulated in a package 80 and electrically connected with a metalized area on the inner surface of the package 80 through a metal bonding wire 50, and the metalized area in the package 80 is led out through a pin 70 to be connected with an external circuit for inputting/outputting an electrical signal. In addition, the optoelectronic element can be mounted on one end of the lead frame, and the other end of the lead frame extends out of the tube shell to be used as a pin.

When using a photocoupler, pins are typically soldered to a circuit board (e.g., PCB), and then ultrasonically cleaned to thoroughly remove the solder remaining on the circuit board. However, ultrasonic cleaning easily causes unstable electrical connection of the metal bonding wires, which not only affects the reliability and service life of the photocoupler, but also easily causes the problem of functional failure. Along with the wider application range of the miniaturized photoelectric coupler, the pin installation connection of the miniaturized photoelectric coupler is limited, for example, the existing fully-sealed photoelectric coupler in the market is influenced by factors such as the packaging form and the shell size of the photoelectric coupler, and the miniaturized photoelectric coupler is difficult to apply to a hybrid integrated circuit, so that the application of the photoelectric coupler is limited. Therefore, development of a novel photocoupler capable of being mounted independently of a welding method and improving applicability of the photocoupler has been desired.

Disclosure of Invention

In order to solve or improve the above-mentioned problems in the prior art, the present utility model provides a semi-hermetic photo-coupler which can be mounted independently of soldering.

In order to achieve the above object, the present utility model provides a photocoupler comprising a substrate, a light emitter, a light receiver, a light guide layer and a light shielding layer, wherein,

the substrate is provided with a first surface and a second surface which are opposite, the first surface is provided with a plurality of metalized areas, the metalized areas are used for being electrically connected with the circuit board, and the second surface is used for mounting the substrate on the circuit board;

the light emitter and the light receiver are arranged on the first surface of the substrate and are respectively and electrically connected with the corresponding metallized areas;

the light guide layer covers the first surface of the substrate and covers the light emitter and the light receiver; the shading layer covers the outer side of the light guide layer, and the light guide layer and the shading layer can realize optical coupling between the light emitter and the light receiver.

According to the scheme, the substrate and the circuit board can be fixed in a mode of not depending on pin welding, so that adverse effects on metal bonding wires caused by ultrasonic cleaning after pin welding in the prior art are avoided.

In one alternative, the light guiding layer and the light shielding layer completely cover all metallized areas of the first surface of the substrate.

In one alternative, the first surface of the substrate has exposed metallized areas not covered by the light guiding layer and the light shielding layer.

The light guide layer has the functions of light guide and light condensation, light emitted by the light emitter passes through a light passage formed by the light guide layer and reaches the surface of the light guide layer, the light shielding layer seals the light in a space defined by the inner surface of the light shielding layer (or the surface of the light guide layer), total reflection of light is completed, and the reflected light is ensured to be received by the light receiver to the greatest extent.

Preferably, the metallised region extends from the first surface to the second surface of the substrate; the metallized area on the second surface is used for electrically connecting with the circuit board through conductive adhesive. The preferred scheme enables the application of a part of bonding wires to be reduced, the conductive adhesive can play a role of fixing the substrate and forming electrical connection with elements on the substrate, and the possibility that the ultrasonic cleaning after pin welding causes adverse effects on the metal bonding wires is further reduced.

Preferably, the substrate side has a notch, and the metallization region extends to the second surface via the notch.

Preferably, the metallized regions are exposed for electrically connecting the circuit board through the bond wires.

Preferably, the substrate is adhered to the circuit board by an insulating adhesive.

Preferably, the plurality of metallized regions includes a first metallized region to a fourth metallized region; the electrode on the back of the light emitter is adhered to the first metallization region through conductive adhesive, and the electrode on the front of the light emitter is electrically connected to the second metallization region through bonding wires;

the electrode on the back of the light receiver is adhered to the third metallization region through conductive adhesive, and the electrode on the front of the light receiver is electrically connected to the fourth metallization region through bonding wires.

Preferably, each electrode of the light emitter and/or light receiver is electrically connected to a different metallized area by a bonding wire.

Preferably, at least one of the plurality of metallized regions has a location area and adjacent metallized regions are spaced 0.1mm to 1mm, preferably 0.4mm to 0.8mm, to meet the requirements of isolation characteristics between the input and output ends of the optocoupler.

In summary, the above technical solution provided in the present disclosure breaks the constraint of the conventional fully-sealed packaging structure on the mounting manner and application range of the photo-coupler, and provides a semi-sealed photo-coupler, which not only can be mounted on a circuit board by adhesion, but also can be applied to a hybrid integrated circuit, especially a thick film hybrid integrated circuit, so that the application range is wider. In addition, in the installation process, the traditional welding mode can be replaced by adopting an adhesive mode, so that ultrasonic cleaning is not needed, adverse effects of ultrasonic cleaning on the metal bonding wire are avoided, and therefore, the reliability of the product is higher and the service life is longer. In addition, as the photoelectric coupler does not adopt a full-sealing structure, compared with products adopting full-sealing packaging forms such as DIP or SOP, the photoelectric coupler has smaller volume and lighter weight, and further improves the application prospect.

Through carrying out reasonable layout to the metallization region on the front of the substrate, especially carrying out reasonable setting to the interval between the metallization region, make photoelectric coupler can satisfy the requirement of isolation voltage, also satisfy the technical index requirement of current transmission ratio.

Drawings

FIG. 1 is a schematic diagram of a typical prior art optocoupler;

fig. 2 is a schematic structural diagram of a photocoupler according to an embodiment of the present disclosure;

FIG. 3 is a schematic cross-sectional view of a photo-coupler provided in an embodiment of the present disclosure;

fig. 4 is a schematic structural diagram of a substrate and a metallization region thereon in a photo-coupler according to an embodiment of the present disclosure;

fig. 5 is a schematic structural diagram of a metallization region extending to a back surface of a substrate in a photo-coupler according to an embodiment of the disclosure;

FIG. 6 illustrates an exemplary mounting of a light emitter and light receiver on a metalized area;

fig. 7 shows an exemplary installation of a further light emitter and light receiver on a metallization region.

The drawing is marked:

10: a substrate; 20: a light guide layer;

30: a light shielding layer; 41: a light emitter;

42: a light receiver; 43: an optical path;

50: a bonding wire; 60: a metallized region;

70: a pin; 80: a tube shell;

wherein, different cross-section lines in the drawings represent different layer structures, and arrows represent light paths; a fine line structure such as a bonding wire represents only an example of an electrical connection, not a shape feature; the metallized areas identified by different letters are insulated from each other.

Detailed Description

Embodiments of the present disclosure are described in detail below with reference to the attached drawings. When the following description refers to the accompanying drawings, the same numbers in different drawings refer to the same or similar elements, unless otherwise indicated. The following examples are illustrative, and the embodiments described therein are not representative of all embodiments consistent with the present application.

It should be appreciated that although the present application employs ordinal terms such as "first," "second," etc., these ordinal terms are merely used to distinguish one type of thing from another, and do not represent a sequence, importance, or quantity thereof. The features of the examples and embodiments described below may be combined with each other without conflict.

As shown in fig. 2 and 3, the present disclosure provides a half-sealed type optocoupler including an optoelectric element, a substrate 10, a light guide layer 20, and a light shielding layer 30. Wherein the substrate 10 has a first surface and a second surface, typically the first surface and the second surface, i.e. the front and the back; the photoelectric element includes a light emitter 41 and a light receiver 42, both the light emitter 41 and the light receiver 42 being disposed on the first surface of the substrate 10; the light guide layer 20 covers the light emitter 41 and the light receiver 42, and is filled between the light emitting surface (upper surface thereof in the example of fig. 3) of the light emitter 41 and the light receiving surface (upper surface thereof in the example of fig. 3) of the light receiver 42. The light shielding layer 30 covers the outside of the light guiding layer 20.

Illustratively, the light guiding layer 20 is filled with a light guiding glue, and the light shielding layer 30 is light shielding glue. The light guide layer 20 has the functions of light guide and light condensation, and the light emitted by the light emitter 41 passes through the light guide layer 20 and reaches the surface of the light guide layer 20, and the light shielding layer 30 seals the light in a space defined by the inner surface of the light shielding layer 30 (or the outer surface of the light guide layer 20), so that a light path 43 between the light emitting surface of the light emitter 41 and the light receiving surface of the light receiver 42 is formed; the light guide layer 20 and the light shielding layer 30 desirably perform total reflection of light and ensure that the reflected light is received by the light receiver 42 to the maximum extent.

In an alternative embodiment, the light guiding layer 20 covers the first surface of the substrate 10, and the cross section (longitudinal cross section) of the light guiding layer along the thickness direction of the substrate 10 is in an arch bridge shape, and the specific geometric feature is not limited in this disclosure, and can be reasonably determined according to factors such as the distance between the light emitter 41 and the light receiver 42, the glue amount, and the glue property, so long as a good light path can be established, so that the light emitted by the light emitter 41 is transmitted inside the light path and forms total reflection as far as possible, and the coupling efficiency of the light path is ensured. In addition, the light shielding layer 30 or the light guiding layer 20 also completely wraps the bonding wire 50 (in the embodiment, the bonding wire) to form protection, so as to ensure the reliability of the photoelectric coupler and avoid the bonding wire 50 from being damaged due to external mechanical pressure and the like.

The composition of the light guide layer 20 and the light shielding layer 30 is not limited in the present disclosure, and in a typical embodiment, the main raw material of the light guide layer 20 is an organic resin composition including a resin matrix and a curing agent; the main raw material component of the light shielding layer 30 includes white solid powder such as titanium oxide powder in addition to the organic resin composition. The organic resin compositions used in the light guide layer 20 and the light shielding layer 30 may be the same in composition, but may be the same or different in ratio. By adjusting the components of the organic resin composition, the light guide layer 20 and the light shielding layer 30 having different physicochemical parameters can be obtained accordingly. The resin matrix and the curing agent can be selected from materials commonly used for a light guide layer and a light shielding layer in the current photoelectric coupler.

The material of the substrate 10 is not limited in this disclosure, and the substrate 10 may be a ceramic substrate, particularly a 90% black ceramic (black alumina ceramic), which has excellent characteristics of good insulation, small expansion coefficient, high thermal conductivity, high mechanical strength, good light shielding property, wear resistance, low dielectric loss, low density, and the like. By adopting the ceramic substrate, the advantage of light weight of the ceramic substrate can be exerted, and the light weight of an optical coupler product can be realized.

As shown in fig. 4, the first surface of the substrate 10 is provided with a plurality of metallized areas 60 for electrically connecting the electrodes of the light emitter 41 and the light receiver 42; the second surface is used to secure the substrate 10 to a circuit board to which the metallized area 60 can be electrically connected.

For example, the substrate 10 may have a substantially square plate-like structure, and in the case where the photo-coupler includes only one light emitter 41 and one light receiver 42, the substrate 10 may be provided with four metalized areas. As shown in fig. 4 and 6, a metallization region 60 is provided near each corner of the front surface of the substrate 10, and four metallization regions 60 are insulated from each other. For convenience of description, four metallized regions are labeled a-D, respectively, where a and D are diagonally disposed and B and C are diagonally disposed. For convenience of locating the pins, at least part of the metallised zones 60 are irregularly shaped, i.e. have locating areas for locating the pins. Such as the irregularly shaped metallized regions B and C of fig. 4, wherein the metallized region B comprises a rectangular region and a location region extending toward the metallized region D, and the metallized region C comprises a rectangular region and a location region extending toward the metallized region a.

It should be understood that, although the embodiment discloses the structural features of one light emitter 41 and one light receiver 42 (single light emission and single light receiving), the technical solution of the present disclosure is not limited thereto, and other numbers of light emitters and/or light receivers may be provided based on the same technical idea, for example, for a linear optocoupler, which generally includes one light emitter and two light receivers, the number and positions of the metallized areas may be reasonably set according to factors such as a circuit connection relationship.

According to an embodiment of the present disclosure, as shown in fig. 6, the electrode on the back side of the light emitter 41 is adhered to the first metalized region C by conductive paste, and the electrode on the front side is electrically connected to the second metalized region a by a bonding wire 50; the electrode on the back side of the light receiver 42 is adhered to the third metallized region B by conductive adhesive, and the electrode on the front side is electrically connected to the fourth metallized region D by the bonding wire 50.

It should be understood that the light emitter 41 and the light receiver 42 may be disposed diagonally, such as in the structure shown in fig. 6, where the light emitter 41 and the light receiver 42 are mounted on the metalized areas C and B, respectively, and may be mounted on the metalized areas a and D, respectively. Alternatively, the light emitter 41 and the light receiver 42 may be disposed on the same side, for example, in the structure shown in fig. 7, and may be mounted on the metalized areas a and B, respectively, or may be mounted on the metalized areas C and D, respectively. Considering the subsequent glue spreading process, if the latter arrangement mode is adopted, the glue easily flows out of the substrate and is not easy to control, so that the former diagonal (refer to fig. 6) arrangement mode is adopted in practice.

As described above, the light emitter 41 is adhered to the metalized region C by the conductive adhesive, so that the electrode on the back side of the light emitter 41 is electrically connected to the metalized region C while the light emitter 41 is fixed on the substrate 10, and the electrode on the front side of the light emitter 41 is electrically connected to the metalized region a by the metal bonding wire 50; similarly, the light receiver 42 may also be fixed to the metallized area B by conductive adhesive and electrically connected to the metallized area B via the electrode on the back side of the light receiver and the electrode on the front side of the light receiver 42.

In the above-described structures shown in fig. 6 and 7, the rear surface and the front surface of the light emitter 41 and the light receiver 42 are provided with electrodes, so that electrical connection with the metallized region can be achieved by conductive paste; when the electrodes of the light receiver 42 are all disposed on the front surface of the chip, the insulating adhesive can be used to bond the back surface of the chip and the metallized area on the front surface of the substrate 10, and the electrodes on the front surface are electrically connected with the corresponding metallized areas by using metal bonding wires.

Spacing a between metallized regions for bonding optoelectronic components (referenceReferring to the labels in fig. 4, 6 and 7), parameters such as isolation characteristics and Current Transfer Ratio (CTR) of the photocoupler are affected. Generally, the larger the distance a, the more advantageous the isolation voltage is, but the light loss may be increased, and the transmission efficiency may be reduced, so that the current transmission ratio may not meet the design requirement. Conversely, the smaller the distance a is, the better the current transmission ratio is, but the isolation voltage value is reduced. To meet the isolation characteristics between the input and output of the photocoupler (such as isolation resistance > 10) ¹¹ Omega; the distance a between the metallized areas 60 on the substrate 10 for bonding the photovoltaic elements can be controlled between 0.1mm and 1mm, in a preferred embodiment between 0.4mm and 0.8mm, as required by the isolation voltage greater than 1000V (DC)) and the current transmission ratio (designed as an adjustable parameter according to the requirements of use).

According to the embodiment of the present disclosure, the light guide layer 20 and the light shielding layer 30 may entirely cover the metallized region 60 of the front surface of the substrate 10, or may cover only a portion of the front surface of the substrate 10 to expose a portion of the metallized region 60.

Regarding the embodiment in which the light guide layer 20 and the light shielding layer 30 entirely cover the metallized region 60 on the front surface of the substrate 10, reference may be made to the structure shown in fig. 2 or 3, in which the light guide layer 20 and the light shielding layer 30 entirely cover the first surface of the substrate 10, the metallized region 60 on the first surface of the substrate 10, and various elements and bonding wires 50 on the first surface. For this embodiment, the metallized regions may also be provided on the back and side surfaces of the substrate 10, the metallized regions on the front and back surfaces of the substrate 10 being correspondingly provided, and the electrical connection being correspondingly established through the metallized regions on the side surfaces of the substrate 10. It is also understood that the metallized region 60 on the front side of the substrate 10 extends through the side of the substrate 10 to the back side. For example, the metallized areas A1-D1 on the back side of the substrate 10 in FIG. 5 correspond to the metallized areas A-D on the front side of the substrate 10 in FIG. 4, respectively. In this way, during the mounting process, the substrate 10 may be fixed to the circuit board by means of conductive adhesive and electrically connected to the wiring on the circuit board.

For the embodiment in which the light guiding layer 20 and the light shielding layer 30 only cover part of the front surface of the substrate 10, the light guiding layer 20 and the light shielding layer 30 do not cover the front surface of the substrate 10 completely, the metallized area 60 on the front surface of the substrate 10 is not covered completely, or the exposed metallized area which is not covered by the light guiding layer 20 and the light shielding layer 30 exists on the front surface of the substrate 10, the foregoing processing manner can be adopted, and the metallized areas are arranged on the side surface and the back surface of the substrate 10 to realize electrode extraction, and electrical connection is established with the wiring on the circuit board through conductive adhesive. In addition, the exposed metallized areas on the front side of the substrate 10 may be electrically connected to the wiring on the circuit board by metal bonding wires, and an insulating paste may be provided between the circuit board and the back side of the substrate 10 to fix the two.

Whether the light guide layer 20 and the light shielding layer 30 completely cover the metallized area 60 on the first surface of the substrate 10 or not, the second surface of the substrate 10 and the circuit board can be fixed by means of conductive adhesive/insulating adhesive bonding, so that adverse effects on metal bonding wires caused by ultrasonic cleaning after pin welding in the prior art are avoided. The photoelectric coupler with the structure can be used in a hybrid integrated circuit, for example, the photoelectric coupler is bonded to a circuit manufactured by a thick film process (namely, a thick film hybrid integrated circuit) by adopting conductive adhesive, or the photoelectric coupler is bonded to the circuit by adopting insulating adhesive, and the photoelectric coupler is electrically connected by adopting a metal bonding wire mode.

According to the embodiment of the present disclosure, as shown in fig. 4 to 7, since the photo coupler itself has a limited size and the substrate adhesion and bonding areas are limited, the conventional punching process is not suitable, and thus a notch design is added to the side of the substrate 10, and the metalized area of the side of the substrate 10 may be disposed at the notch. It will be appreciated that the notch may be semicircular (including more or less semicircle) in transverse cross-section through the thickness of the substrate 10; of course, the recesses may be irregular, so long as the corresponding effective electrical connection between the front and back metallization regions 60 of the substrate 10 is ensured.

The present disclosure also provides a basic preparation process of the above-mentioned photocoupler, which includes the following steps:

s1, providing a ceramic matrix, wherein at least the front surface of the ceramic matrix is provided with a metalized area;

s2, adhering the light emitter and the receiver to the metallized area on the front surface of the ceramic matrix;

s3, connecting electrodes of the light emitter and the light receiver and corresponding metallized areas by using bonding wires (so the bonding wires are also called as bonding wires) by adopting a pressure welding process;

s4, dispensing, namely taking the prepared organic resin composition as the center of the midpoint of the luminous body and the receiver, keeping the ceramic matrix in a heated state, uniformly covering the luminous body and the receiver with colloid, and then curing at high temperature to form a semi-elliptic, transparent and soft gel-like light guide layer with certain elasticity.

S5, gluing, namely mixing the organic resin composition and the white powder mixture in proportion and fully stirring, and then vacuumizing to fully remove bubbles in the shading glue so as to avoid influencing shading effect and appearance. On the basis of the previous step (the light guide layer is formed), a shading adhesive is coated to completely wrap the light guide layer. Then, pretreatment is carried out in an oven at 70-90 ℃ to further remove micro bubbles in the material, and then the material is solidified at high temperature to form a shading layer.

Compared with the traditional photoelectric coupler, the photoelectric coupler provided by the embodiment of the disclosure breaks through the constraint of the traditional full-sealed packaging structure on the installation mode and the application range of the photoelectric coupler, and provides a half-sealed photoelectric coupler structure which can be installed on a circuit board through bonding and is applied to a hybrid integrated circuit, particularly a thick film hybrid integrated circuit, so that the application range is wider. In addition, in the installation process, the traditional welding mode is replaced by the bonding mode, so that ultrasonic cleaning is not needed, adverse effects of ultrasonic cleaning on the metal bonding wire are avoided, and therefore the reliability of the product is higher and the service life is longer. In addition, as the photoelectric coupler does not adopt a full-sealing structure, compared with products adopting packaging forms such as DIP (dual in package) or SOP (solid state optical package) and the like, the photoelectric coupler is smaller in volume and lighter in weight; in addition, the ceramic substrate is adopted, so that the advantage of light weight of the ceramic substrate can be exerted, the light weight of the product is further realized, and the application prospect of the product is improved.

In addition, according to the embodiment of the disclosure, through reasonably arranging the metallized areas on the front surface of the ceramic substrate, particularly reasonably setting the intervals between the metallized areas, the photoelectric coupler can meet the requirement of isolation voltage and the technical index requirement of Current Transmission Ratio (CTR).

The above embodiments are merely for illustrating the technical solution of the present disclosure, and are not limiting thereof; although the present disclosure has been described in detail with reference to the foregoing embodiments, it should be understood by those of ordinary skill in the art that: the technical scheme described in the foregoing embodiments can be modified or some technical features thereof can be replaced by equivalents; such modifications and substitutions do not depart from the spirit and scope of the corresponding technical solutions of the embodiments of the present disclosure.

Claims (10)

1. A photoelectric coupler is characterized by comprising a substrate (10), a light emitter (41), a light receiver (42), a light guide layer (20) and a shading layer (30), wherein,

the substrate (10) has opposed first and second surfaces, the first surface having a plurality of metallized areas (60) disposed thereon, the metallized areas (60) for electrical connection with a circuit board, the second surface for mounting the substrate (10) to the circuit board;

the light emitter (41) and the light receiver (42) are arranged on the first surface of the substrate (10) and are respectively and electrically connected with the corresponding metalized areas (60);

the light guide layer (20) covers the first surface of the substrate (10) and covers the light emitter (41) and the light receiver (42); the light shielding layer (30) covers the outer side of the light guiding layer (20), and the light guiding layer (20) and the light shielding layer (30) can realize optical coupling between the light emitter (41) and the light receiver (42).

2. The optocoupler of claim 1 wherein the light guiding layer (20) and the light shielding layer (30) completely cover all metallized areas (60) of the first surface of the substrate (10).

3. The optocoupler of claim 1 wherein there is an exposed metallized area of the first surface of the substrate (10) not covered by the light guiding layer (20) and the light shielding layer (30).

4. A photo-coupler according to claim 2 or 3, characterized in that the metallized area (60) extends from a first surface to the second surface of the substrate (10);

the metallized area on the second surface is used for being electrically connected with the circuit board through conductive adhesive.

5. The optocoupler of claim 4 wherein the substrate (10) has a notch in the side; the metalized region (60) extends to the second surface via the notch.

6. A optocoupler according to claim 3, wherein the exposed metallized areas are used for electrically connecting the circuit board by means of bond wires.

7. The optocoupler of claim 6 wherein the substrate is bonded to the circuit board by an insulating adhesive.

8. The optocoupler of claim 1 wherein the plurality of metallized regions (60) comprises first through fourth metallized regions, wherein:

the electrode on the back of the light emitter (41) is adhered to the first metallization region through conductive adhesive, and the electrode on the front of the light emitter is electrically connected to the second metallization region through bonding wires (50);

the electrode on the back of the light receiver (42) is adhered to the third metalized area through conductive adhesive, and the electrode on the front of the light receiver is electrically connected to the fourth metalized area through bonding wires (50).

9. The optocoupler of claim 1, wherein the electrodes of the light emitter (41) and/or light receiver (42) are each electrically connected to a different metallized area by means of a bonding wire (50).

10. The optocoupler of any one of claims 1, 8 or 9 wherein at least one of the plurality of metallized regions has a locating region and adjacent metallized regions are spaced apart by a distance of 0.1mm to 1.0mm.