JPH04252082A - Optically coupled device - Google Patents

Abstract

PURPOSE:To facilitate an increase in the performance of a photointerrupter or the like and to rationalize the manufacturing process of the photointerrupter or the the like. CONSTITUTION:Plated electrode parts 16 and 18 are respectively formed in recessed parts 15 and 17 in a package 10, a photodetector 11 and a light-emitting element 13 are respectively mounted on these electrode parts 16 and 18 and the photodetector 11 and the element 13 are molded with a light-transmitting resin 21. At this time, condensing lenses 23 and 25 are also formed with the light-transmitting resin 12 simultaneously with the photodetector 11 and the element 13. Whereupon, the optical characteristics of a photointerrupter are improved by the reflection of light from the parts 16 and 18 and the lenses 23 and 25 and the manufacturing process of the photointerrupter is simplified compared to that in the case the lenses 23 and 25 are bonded independently.

Description

[Detailed description of the invention]

0001

[Field of Industrial Application] The present invention relates to an optical coupling device (reflection type photointerrupter) which is an optical functional component.
In particular, the present invention relates to optical coupling devices frequently used in paper selection of copying machines, VTRs, and various microcomputer-controlled devices.

0002

2. Description of the Related Art The structure of a conventional optical coupling device (reflection type photointerrupter) will be explained with reference to FIGS. 4 and 5.

As shown in the figure, in the conventional optical coupling device, an anode terminal A, an emitter terminal E, a collector terminal C, and a cathode terminal K of a lead frame are insert-molded in an external resin package (case) 1 having a light-shielding property. , a light emitting element (light emitting diode) D is mounted between an anode terminal A and a cathode terminal K, a light receiving element (phototransistor) T is mounted between an emitter terminal E and a collector terminal C, and each element is connected to a lead frame by wire bonding, etc. The wires were connected using , and each element was sealed with resin so as to surround each element using a translucent resin 2 . Note that 1a in the figure is a recessed portion for potting the translucent resin 2.

0004

[Problems to be Solved by the Invention] However, based on the above conventional method, the insert metal frame, that is,
Lead frame and external and internal mold resin 1, 2
Due to the difference in thermal expansion coefficient between the lead frame and the resin, a gap is created between the lead frame and the resin during temperature cycling, temperature shock, etc. tests, or during solder reflow. Moisture passes through this gap, causing element deterioration and Furthermore, the device had a serious drawback in that discharge occurred between the terminals and caused a shoot (open shoot), which affected the reliability of the device.

Furthermore, since the wall surface of the recess 1a is only formed of the resin 1, the reflectance is low, and the light rays emitted from the chip of the light emitting element D are not effectively extracted to the outside.

[0006] Therefore, in order to compensate for the above-mentioned drawbacks, the present applicant devised an optical coupling device shown in FIGS. 6 and 7 (proposal example 1).

In the figure, 3a and 3b are reflective surfaces and electrode parts formed by gold or silver plating, and these electrode parts 3a and 3b
are routed to the back surface of the board through through-hole portions 4a and 4b. Further, 5 is a soldering part.

A light emitting element D and a light receiving element T are mounted on the electrode parts 3a and 3b, respectively, and internal connections are made with wire bonds 6. An internal molding resin 2 such as transparent silicone resin or transparent epoxy resin is molded onto these by a potting method.

In this way, since the plated electrode films 3a and 3b are formed instead of the lead frame, it is not necessary to take into account the difference in thermal expansion coefficient between the metal frame and the resin, as in the conventional case. Moreover, the amount of light can be increased by reflecting the light with plating.

However, according to proposal example 1 shown in FIGS. 6 and 7, the shape of the transparent resin 2 on the front surface becomes flat or concave due to curing and shrinkage of the transparent resin 2, so that the light rays taken out to the outside are The amount of radiation is reduced, the sensitivity is low, the beam direction is wide, and the resolution is poor. That is, 1) The front surface of the transparent resin 2 is planar or concave, forming a critical angle with the molded resin window surface, which causes light confinement, lowering the external quantum efficiency and lowering the sensitivity. It was hot.

2) Since the shape of the molded resin window is flat or concave, the emission destination from the molded resin window is widened, making it impossible to improve the resolution.

In order to improve these drawbacks, a semicircular lens 8 or a ball lens as shown in FIG. 7 may be bonded to the molded resin window, but in this case, an additional process of bonding the lens is required and the work is labor intensive. becomes complicated.

SUMMARY OF THE INVENTION In view of the above-mentioned problems, it is an object of the present invention to provide an optical coupling device that can rationalize the manufacturing process, be inexpensive, and realize high performance.

[0014]

[Means for Solving the Problems] As shown in FIGS. 1 to 3, the means for solving the problems according to the present invention includes:
In an optical coupling device in which a light emitting element 11 and a light receiving element 13 are arranged so as to be optically coupled and detect the presence or absence of an object to be detected without contact, a light emitting element mounting device for mounting the light emitting element 11 on the package 10 is provided. recess 15 and light receiving element 1
A light receiving element mounting recess 17 for mounting the light emitting element 11 is formed, and a light receiving element mounting recess 17 for mounting the light emitting element 11 is formed in the light emitting element mounting recess 15 for reflecting the irradiated light from the light emitting element 11 forward and for electrically connecting to the light emitting element 11. A light-emitting side plated electrode portion 16 is formed in the light-receiving element mounting recess 17 for reflecting incident light from the front to the light-receiving element 13 and electrically connecting it to the light-receiving element 13. 18 is formed, the light-emitting element 11 is mounted on the light-emitting side plating electrode part 16, and these are molded with a light-transmitting resin 21 to form a light-emitting side transparent resin body 22, and the light-emitting side transparent resin body 22 is formed. A light-emitting side condensing lens body 23 for condensing the irradiated light from the light-emitting element 11 to the outside is integrally formed on the body 22, and the light-receiving element 13 is mounted on the light-receiving side plated electrode section 18. is molded with a light-transmitting resin 21 to form a light-receiving-side light-transmitting resin body 24, and the light-receiving-side light-transmitting resin body 24 has a light-receiving side concentrator for condensing incident light from the outside onto the light-receiving element 13. The optical lens body 25 is integrally formed.

[0015]

[Operation] In the above problem-solving means, at the time of manufacturing,
Recesses 15 and 17 are formed in the package 10, and the recess 1
5 and 17 are subjected to gold or silver plating to form a light-emitting side plated electrode section 16 and a light-receiving side plated electrode section 18.

Next, the light emitting element 11 and the light receiving element 13 are mounted on the plated electrode parts 16 and 18 of the package 10, respectively, and a transparent resin body 2 is placed in each recess 15 and 17 with a transparent resin 21.
2 and 24 to complete the reflective photointerrupter.

At this time, the light-transmitting resin bodies 22 and 24 are used to integrally form condensing lens bodies 23 and 25, respectively, by transfer molding or injection molding. Then, when providing lenses on the front surfaces of the transparent resin bodies 22 and 24 to improve light convergence, the process of adhering lenses after resin molding as in Proposed Example 1 is omitted, thereby simplifying the work.

[0018]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a sectional view of an optical coupling device showing an embodiment of the present invention, FIG. 2 is a perspective view thereof, and FIG. 3 is a similar view of FIG.
It is a YY sectional view of .

As shown in the figure, the reflective optical coupler (reflective photo interrupter) of this embodiment has a light emitting element 11 (L
An ED chip) and a light receiving element 13 (phototransistor) are arranged so as to be optically coupled, and the presence or absence of an object to be detected is detected without contact.

When manufacturing the optical coupling device, the package 10 is formed by regularly arranging several hundred pieces on a single organic resin substrate, and then individually cutting them with a dicing saw.
It is formed into a substantially rectangular parallelepiped shape. As shown in FIG. 1, the package 10 is formed with a light emitting element mounting recess 15 for mounting the light emitting element 11 and a light receiving element mounting recess 17 for mounting the light receiving element 13. Then, each recess 15
, 17 is provided with a light shielding wall 1 in the center thereof to prevent crosstalk between the light emitting element 11 and the light receiving element 13.
They are placed side by side with 4 in between.

A light-emitting side plating electrode portion 16 is three-dimensionally provided in the light-emitting element mounting recess 15, and a light-receiving-side plating electrode portion 18 is three-dimensionally provided in the light-receiving element mounting recess 17. ing.

The light emitting side plated electrode portion 16 is shown in FIGS.
A primary electrode 16a on which the light emitting element 11 is directly mounted via an insulating part Become.

The light-receiving side plated electrode portion 18 has an insulating portion
The primary electrode 18 on which the light receiving element 13 is directly mounted via the
a, and a secondary electrode 18b which is bonded and connected via a bonding wire W.

The electrodes 16a, 16b, 18a, 18b of the electrode portions 16, 18 on the receiving/emitting side are connected to the through hole 1.
9 (see FIG. 2) to the back surface of the package 10. Then, the light emitting side plating electrode portion 16
A light emitting element 11 is mounted on the light receiving side plated electrode section 1.
A light receiving element 13 is mounted on 8.

The plated electrode parts 16 and 18 are used not only for mounting the light emitting element 11 and the light receiving element 13, but also for mounting the light emitting element 11 and the light receiving element 13.
In order to improve the light directivity by reflecting the irradiated light from the light emitting element 11 and the light incident on the light receiving element 13 on the inclined surface, the entire inner peripheral surface of the recesses 15 and 17, except for the insulating part X, is plated. It has been subjected.

The light emitting element 11 is mounted on the light emitting side plating electrode section 16, and these are molded with a light transmitting epoxy resin 21 to form a light emitting side transparent resin body 22. The window surface side of the photoresin body 22 is attached to the package 10.
A semi-cylindrical light emitting side condensing lens body 2 for condensing the irradiated light from the light emitting element 11 to the outside by protruding further.
3 are integrally formed, for example, by transfer molding.

Similarly, the light-receiving element 13 is mounted on the light-receiving side plated electrode portion 18, and these elements are covered with a light-transmitting epoxy resin 2.
1 is molded to form a light-receiving side transparent resin body 24, and by making the window surface side of the light-receiving side transparent resin body 24 protrude from the package 10, incident light from the outside is focused on the light-receiving element 13. A semi-cylindrical light-receiving side condensing lens body 25 for
are integrally formed, for example, by transfer molding.

[0029] Of the plated electrode portions, the electrodes routed around the back surface of the package are used for surface mounting on a substrate.

The above reflective photointerrupter is manufactured as follows.

First, a resin case substrate is molded in a state in which a large number of packages 10 are integrally connected. At this time, the surfaces of each of the recesses 15 and 17 are roughened by etching (plating grade treatment). and,
Gold or silver plating is applied to each of the concave portions 15 and 17 to form a light-emitting side plated electrode portion 16 and a light-receiving side plated electrode portion 18.

At this time, it is routed through the through hole 19 to the back surface of the package 10.

Next, the light-emitting element 11 and the light-receiving element 13 are mounted on the package 10 and bonded using bonding wires W, and then a translucent Mold cure with good epoxy resin 21.

At this time, the light-emitting side condensing lens body 23 and the light-receiving side condensing lens body 25 are formed in each of the light-transmitting resin bodies 22 and 24, respectively, using a mold that gives them a lens shape. .

Thereafter, the package substrate is individually cut into chips using a dicing saw to form a reflective photointerrupter having a lens-shaped window as shown in FIG.

By providing lenses on the front surfaces of the transparent resin bodies 22 and 24 in this way, the following 1) to 3) can be achieved.

1) Improvement of object detection position accuracy.

2) Improvement in sensitivity.

3) Lower current on the light emitting element side due to improved external quantum efficiency.

That is, improvements in higher resolution and higher sensitivity can be realized.

In this case, as in Proposed Example 1 shown in FIGS. 6 and 7, there is no need to glue the kamaboko lens etc. after potting, and the shape of the front surface (window) of the molded resin can be changed at once to the lens shape. It can be done.

[0042] Therefore, it is possible to reduce the cost by simplifying the manufacturing process.

Furthermore, the light emitting element 11 or the light receiving element 13
On the other hand, the light can be reflected by the plated electrode parts 16 and 18, and the optical coupling characteristics of both the elements 11 and 13 can be significantly improved.

It should be noted that the present invention is not limited to the above embodiments, and it goes without saying that many modifications and changes can be made to the above embodiments within the scope of the present invention.

For example, in the above embodiment, the lenses 23, 2
Although the shape of No. 5 is a semi-cylindrical fish cake, it may be semi-spherical.

[0046]

Effects of the Invention As is clear from the above explanation, according to the present invention, since the condenser lens body is integrally formed on each light-transmitting resin body by transfer molding or the like, the front surface of the light-transmitting resin body is When providing a lens on the lens, the lens bonding step after resin molding can be omitted.

Furthermore, since a plated electrode portion is formed in each concave portion, light can be reflected at this electrode portion, and the optical characteristics of both elements can be significantly improved. effective.

From the above, it is possible to rationalize the manufacturing process and easily realize high performance at low cost.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of a reflective optical coupling device showing one embodiment of the present invention.

FIG. 2 is also a perspective view thereof.

FIG. 3 is a sectional view taken along the YY line in FIG. 2;

FIG. 4 is a plan view showing a conventional reflective optical coupling device.

FIG. 5 is a circuit diagram of a general reflective optical coupling device.

FIG. 6 is a perspective view showing proposal example 1.

FIG. 7 is a cross-sectional view thereof.

[Explanation of symbols]

10　　　　　　Package 11　　　　　　　　　　　　Light emitting element 13 Photo receiving element 15, 17 Recessed part 16, 18 Plated electrode part 21 Translucent resin 22, 24 Translucent resin body 23, 25 Condensing lens body

Claims (1)

[Claims] 1. An optical coupling device for detecting the presence or absence of an object to be detected without contact, in which a light-emitting element and a light-receiving element are arranged so as to be optically coupled within the same package, wherein the light-emitting element is disposed in the package. A light emitting element mounting recess for mounting a light emitting element and a light receiving element mounting recess for mounting a light receiving element are formed, and the light emitting element is reflected forwardly in the light emitting element mounting recess and the light emitting element is mounted. A light emitting side plated electrode portion is formed for electrical connection to the light receiving element, and a light receiving side plated electrode portion is formed in the light receiving element mounting recess for reflecting incident light from the front to the light receiving element and for electrically connecting to the light receiving element. A plating electrode portion is formed, a light emitting element is mounted on the light emitting side plating electrode portion, and these are molded with a light transmitting resin to form a light emitting side transparent resin body, and the light emitting side transparent resin body is formed. A light-emitting side condensing lens body for concentrating the irradiated light from the light-emitting element to the outside is integrally formed, a light-receiving element is mounted on the light-receiving side plated electrode part, and these are mounted on a transparent resin. A light-receiving-side light-transmitting resin body is formed by molding, and a light-receiving-side condensing lens body for condensing incident light from the outside onto the light-receiving element is integrally formed on the light-receiving-side light-transmitting resin body. An optical coupling device characterized by: