JPH09129913A - Optical device - Google Patents

Abstract

(57) [Summary] [Problem] In a conventional optical device, moisture and the like enter from an interface between a chip mounting lead frame and a sealing resin, and have poor moisture resistance. SOLUTION: A light receiving chip 6, a light receiving side chip mounting lead frame 7 on which the light receiving chip 6 is mounted, a part of the light receiving side chip mounting lead frame 7 and a thermosetting property for sealing the light receiving chip 6. In the optical device comprising the translucent resin body 10 and the thermoplastic light shielding resin body that seals the translucent resin body 10, the translucent resin body 10 of the light-receiving side chip mounting lead frame 7 is In the sealed portion, a through hole 12 having a substantially U-shape is formed so as to surround a surface of the light receiving chip 6 corresponding to the drawing direction of the lead frame 7 for mounting the light receiving side chip and a surface perpendicular to the surface. Is provided.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical device, and more particularly, to a light emitting device which emits signal light in response to an electric signal, a light receiving device which receives the signal light and emits an electric signal, and which integrally includes a light emitting portion and a light receiving portion. The present invention relates to an optical coupling device that detects the presence or absence of an object without contact.

[0002]

2. Description of the Related Art A conventional optical device will be described with reference to an optical coupling device (reflection type photo interrupter) which integrally includes a light emitting portion and a light receiving portion and detects the presence or absence of an object to be detected without contact.

FIG. 5 is an external view of the optical coupling device.
(A) is a plan view, (b) is a right side view,
(C) is a front view. FIG. 6 is an internal configuration diagram of the optical coupling device.

As shown in FIGS. 5 and 6, a conventional optical coupling device includes a light emitting chip 1 including an infrared light emitting diode chip, a light emitting side chip mounting lead frame 2 on which the light emitting chip 1 is mounted, A light emitting side connection lead frame 4 electrically connected to the light emitting chip 1 by a gold wire 3,
The light emitting chip 1, the gold wire 3 and the lead frame 2,
A thermosetting light-emitting side translucent resin body 5 for sealing a part of 4;
A light-receiving chip 6 including a phototransistor, a light-receiving-side chip mounting lead frame 7'on which the light-receiving chip 6 is mounted, and a light-receiving-side connection lead frame 9 electrically connected to the light-receiving chip 6 by a gold wire 8. A thermosetting light-receiving side light-transmitting resin body 10 for encapsulating the light-receiving chip 6, the gold wire 8 and a part of the lead frames 7 ', 9; and light-emitting surfaces of the both light-transmitting resin bodies 5, 10. 5a and a surface other than the light-receiving surface 10a are covered, and a thermoplastic light-shielding resin body 11 that integrally seals both the light-transmitting resin bodies 5 and 10 is provided.

The lead frames 2, 4, 7'and 9 are
In the portion directly covered with the light shielding resin body 11,
The width of each lead frame 2, 4, 7 ', 9 is the inside (the side on which the optical chips 1, 6 are mounted or the side connected by the gold wires 3, 8)> the outside (the lead frames 2, 4, 7') , 9 are exposed), that is, L> L 'as shown in FIG.

The light-transmitting resin bodies 5, 10 are formed by a transfer molding method using a thermosetting resin such as a light-transmitting epoxy resin, and the light-shielding resin body 11 is made of polyethylene sulfide (PPS) resin or the like. It is formed by an injection molding method using a thermoplastic resin having a high heat distortion temperature (260 ° C. or higher).

As described above, in the conventional optical coupling device, the lead frames 2, 4, 7 ', 9 are obtained so that the tensile strength of the lead frames 2, 4, 7', 9 can be obtained at high temperature such as soldering.
A portion where the width of 7 ', 9 is large, that is, a portion of the difference between L and L'shown in FIG.

[0008]

However, in the conventional optical coupling device, the adhesion between the lead frames 2, 4, 7 ', 9 and the light shielding resin body 11 is poor, so that the lead frames 2, 4, 7 are not provided. ′, 9 and the light-shielding resin body 11 allow moisture or the like to easily enter from the outer end portion A, and the lead frames 2, 4, 7 ′, 9 and the translucent resin bodies 5, 10 Insufficient adhesion, lead frame 2,
Since the width L of 4, 7 ′, 9 is large, for example, 0.9 mm, it further penetrates into the inside through the interface between the lead frames 2, 4, 7 ′, 9 and the translucent resin body 5, 10. There was a problem that the moisture resistance was poor.

In particular, the light receiving chip 6 has a larger chip size than the light emitting chip 1 (for example, the light receiving chip: 0.6
× 0.6 mm, light-emitting chip: 0.3 × 0.3 mm), so that moisture and the like could easily reach.

The water content is the light emitting chip 1 or the light receiving chip 6.
When it reaches, the deterioration and malfunction of the chip will occur.

The present invention has been made in view of the above problems, and an object thereof is to provide an optical device capable of improving moisture resistance.

[0012]

According to a first aspect of the present invention, there is provided an optical device, an optical chip, a lead frame for mounting the optical chip, a part of the lead frame for mounting the chip, and the optical chip. In an optical device comprising a thermosetting light-transmitting resin body for sealing a resin and a thermoplastic light-shielding resin body for sealing the light-transmitting resin body, the light-transmitting resin body of the chip mounting lead frame is provided. In the portion sealed by, a substantially U-shaped through hole is provided so as to enclose the surface of the optical chip corresponding to the drawing direction of the chip mounting lead frame and the surface perpendicular to the surface. It is characterized by that.

An optical device according to a second aspect of the present invention seals an optical chip, a chip mounting lead frame on which the optical chip is mounted, a part of the chip mounting lead frame and the optical chip. An optical device comprising a thermosetting light-transmitting resin body and a thermoplastic light-shielding resin body for sealing the light-transmitting resin body, wherein the chip-mounting lead frame is sealed with the light-transmitting resin body. The cut portion is provided with a notch that covers at least the surface of the optical chip corresponding to the pull-out direction of the chip mounting lead frame.

Further, in the optical device according to a third aspect of the present invention, the notch substantially surrounds a surface of the optical chip corresponding to a direction of drawing out the chip mounting lead frame and a surface perpendicular to the surface. It is characterized by having an L-shape.

According to the above structure, in the optical device according to claim 1 of the present invention, the chip mounting lead frame of the optical chip is provided in a portion of the chip mounting lead frame sealed with the translucent resin. Since the through hole having a substantially U-shape is provided so as to surround the surface corresponding to the drawing direction of the and the surface perpendicular to the surface, the chip mounting lead frame and the translucent resin body are formed by the through hole. Since the invasion route of moisture or the like that intrudes from the interface is narrowly limited and the distance of the invasion route can be set to be long, it becomes difficult for moisture and the like to reach the optical chip, and the moisture resistance can be improved. Also, as the distance of the intrusion route increases,
A heat transfer path for heat due to soldering at the time of mounting on a member to be mounted becomes long, heat due to solder hardly reaches the optical chip, and solder heat resistance can be improved.

In the optical device according to the second aspect of the present invention, since the notch is provided to cover at least the surface of the optical chip corresponding to the drawing direction of the chip mounting lead frame, moisture or the like is caused by the notch. The invasion route is restricted and the moisture resistance can be improved.

Further, in the optical device according to the third aspect of the present invention, the notch is substantially formed so as to surround a surface of the optical chip corresponding to the direction of drawing out the chip mounting lead frame and a surface perpendicular to the surface. Because of the L-shaped configuration,
The distance of the intrusion route can be set long, and the moisture resistance can be further improved. In addition, as the distance of the intrusion path becomes longer, the heat transfer path for heat due to soldering at the time of mounting on the mounted member becomes longer, making it difficult for the heat due to soldering to reach the optical chip and improving the solder heat resistance. Can also improve.

[0018]

BEST MODE FOR CARRYING OUT THE INVENTION As in the conventional example, an optical coupling device (reflection type photointerrupter) which integrally includes a light emitting portion and a light receiving portion and detects the presence or absence of an object to be detected without contact is provided. It demonstrates using.

FIG. 1 is an internal configuration diagram showing the structure of an optical coupling device according to a first embodiment of the present invention. Only the points of the present embodiment different from the conventional optical coupling device shown in FIG. 6 will be described.

In the optical coupling device of this embodiment, the structure of the light-receiving side chip mounting lead frame 7 is different from the structure of the light-receiving side chip mounting lead frame 7'in the conventional optical coupling device.

That is, in the lead frame 7 for mounting the light receiving side chip, the direction in which the light receiving side chip mounting lead frame 7 of the light receiving chip 6 is pulled out in the portion sealed by the light receiving side transparent resin body 10. The first through-hole 1 having a substantially U-shape so as to surround the surface corresponding to and the surface perpendicular to the surface.
2 is provided.

The width 1 of the first through hole 12 may be a width that does not adversely affect the arrangement of the light receiving chip 6 and the strength of the light receiving side chip mounting lead frame 7 itself, for example, the light receiving side chip mounting. Lead frame 7 has a thickness of 0.1
When the width is about 5 mm, the width 1 is about 0.1 to 0.2 mm. This is due to the frame manufacturing technology of punching out a width slightly smaller than the plate thickness, and the minimum value is about 0.1 mm.

In the optical coupling device of the present embodiment as described above, considering the entry path of moisture or the like into the resin package, the moisture or the like is taken into account as shown by the arrow in FIG. 7 and the light-shielding resin body 11 penetrates from the outer side end portion A and penetrates the interface through the first through hole 12
Along the inward direction and reaches the light receiving chip 6 from the inner end of the interface where the first through hole 12 is not provided, the light receiving chip 6 is reached from the outer end A of the interface. And the width of the moisture entry path is narrowed.

Further, as for the heat transfer path of heat by soldering when mounting the optical coupling device on the member to be mounted, the distance is narrowed and the width is narrowed similarly to the water penetration path.

Therefore, according to the optical coupling device of the present embodiment, the moisture resistance and the solder heat resistance can be improved.

In the present embodiment, the same effect can be obtained by providing the first through hole in the light emitting side chip mounting lead frame 2 as well as the light receiving side chip mounting lead frame 7. Originally, due to the difference in chip size (light emitting chip: 0.3 × 0.3 mm, light receiving chip: 0.6 × 0.6 mm), the light emitting side receives the distance from the outer end B of the interface to the light emitting chip 1. This is because moisture can reach the light emitting chip 1 even if the first through hole is not provided because it can be made larger than the side.

For this reason, as described above, if the first through hole 12 is provided in at least the light-receiving side chip mounting lead frame 7, the structure can improve the moisture resistance and the solder heat resistance.

FIG. 2 is a diagram showing a main part of the structure of an optical coupling device according to another embodiment. Only points of difference of the present embodiment from the above embodiment will be described.

The optical coupling device of the present embodiment has a second through hole 12a instead of the first through hole 12 of the above embodiment.
Is provided.

The second through hole 12a is formed in a portion of the lead frame 7 for mounting the light receiving side chip sealed by the light transmitting side light-transmitting resin body 10 of the lead frame 7 for mounting the light receiving side chip. The frame 7 is provided in a substantially belt-like shape so as to cover the surface of the frame 7 corresponding to the pulling direction.

According to this structure, the optical coupling device according to the present embodiment is inferior in moisture resistance to the above-described embodiments because the moisture intrusion route cannot be lengthened, but the moisture intrusion route is narrowly restricted. Therefore, the moisture resistance can be improved.

FIG. 3 is an internal block diagram for explaining the structure of the optical coupling device according to the second embodiment of the present invention.
Only points of difference of the present embodiment from the embodiment shown in FIG. 1 will be described.

The optical coupling device of the present embodiment has a first notch 1 instead of the first through hole 12 of the embodiment shown in FIG.
3 is provided.

That is, the first notch 13 is provided at least on the light receiving side chip mounting portion of the light receiving chip 6 in the portion sealed by the light receiving side transparent resin body 10 of the light receiving side chip mounting lead frame 7b. The lead frame 7b is provided in a substantially L shape so as to surround a surface of the lead frame 7b corresponding to the drawing direction and a surface perpendicular to the surface.

According to this structure, the optical coupling device of the present embodiment has at least the light-receiving side chip mounting lead frame 7
By providing the first notch 13 in b, the same moisture resistance and solder heat resistance as those of the embodiment shown in FIG. 1 can be improved.

FIG. 4 is a diagram showing a main part of the structure of an optical coupling device according to another embodiment. Only the points of the present embodiment different from the embodiment shown in FIG. 3 will be described.

The optical coupling device of this embodiment has a second notch 13 instead of the first notch 13 of the embodiment shown in FIG.
This is a structure provided with a.

That is, the second notch 13a is provided in at least the light receiving side chip mounting portion of the light receiving chip 6 in the portion of the light receiving side chip mounting lead frame 7c sealed by the light receiving side transparent resin body 10. The lead frame 7c is provided in a substantially band-like shape so as to cover the surface corresponding to the pull-out direction.

According to this structure, the optical coupling device according to the present embodiment is inferior in moisture resistance to the above-mentioned embodiment because the moisture intrusion route cannot be lengthened, but the moisture intrusion route is narrow. Since it can be limited, the structure has improved moisture resistance.

In the above-described embodiment, the through holes and the notches have a structure that entirely covers the surface of the optical chip in the lead-out direction of the chip mounting lead-out direction. In order to improve the moisture resistance by narrowing the path, it is sufficient to provide a through hole or notch that limits only the width of the chip mounting lead frame. That is, it is not necessary to entirely cover the surface of the optical chip in the lead-out direction of the chip mounting lead frame.

In the above-mentioned embodiment, the optical coupling device is used. However, a double mold type light emitting device which is sequentially sealed with a thermosetting transparent resin body and a thermoplastic light shielding resin body, It goes without saying that the moisture resistance and the solder heat resistance can be improved by providing the above-mentioned through hole or notch even in a single unit such as the light receiving device.

[0042]

As described above, according to the first aspect of the present invention,
According to the optical device described above, in a portion of the chip mounting lead frame sealed with the light-transmitting resin, a surface corresponding to a drawing direction of the chip mounting lead frame of the optical chip and the surface. Since the configuration is such that a substantially U-shaped through hole is provided so as to surround the vertical surface, the penetration path of moisture or the like entering from the interface between the chip mounting lead frame and the translucent resin body is narrowly restricted by the through hole. In addition, since the distance of the intrusion route can be set to be long, it becomes difficult for moisture and the like to reach the optical chip, and the moisture resistance is improved. Also, as the distance of the intrusion route increases,
A heat transfer path for heat due to soldering at the time of mounting on a mounted member becomes long, heat due to soldering hardly reaches the optical chip, and solder heat resistance is also improved.

According to the optical device of the second aspect of the present invention, since the notch is provided so as to cover at least the surface of the optical chip corresponding to the lead-out direction of the chip mounting lead frame, the notch is used. The invasion route of water and the like is narrowed and the moisture resistance is improved.

Further, according to the optical device of the third aspect of the present invention, the notch surrounds a surface of the optical chip corresponding to the direction of drawing out the chip mounting lead frame and a surface perpendicular to the surface. Since it has a substantially L-shaped configuration, it is possible to set a long distance for the intrusion route,
Further, the moisture resistance is improved. In addition, as the distance of the intrusion path becomes longer, the heat transfer path for heat due to soldering at the time of mounting on the mounted member becomes longer, making it difficult for the heat due to soldering to reach the optical chip and improving the solder heat resistance. Also improves.

[Brief description of the drawings]

FIG. 1 is an internal configuration diagram showing a first embodiment of the present invention.

FIG. 2 is a diagram showing a main part of another embodiment.

FIG. 3 is an internal configuration diagram showing a second embodiment of the present invention.

FIG. 4 is a diagram showing a main part of another embodiment.

FIG. 5 is an external view showing a conventional example, (a) is a plan view, (b) is a right side view, and (c) is a front view.

FIG. 6 is an internal configuration diagram of FIG.

[Explanation of symbols]

1 Light emitting chip (optical chip) 2 Light emitting side chip mounting lead frame 5 Light emitting side translucent resin body 6 Light receiving chip (optical chip) 7, 7a, 7b, 7c Light receiving side chip mounting lead frame 10 Light receiving side translucent resin body 11 Light-shielding Resin Body 12 First Through Hole 12a Second Through Hole 13 First Notch 13a Second Notch

Claims (3)

[Claims] 1. An optical chip, a chip mounting lead frame on which the optical chip is mounted, a thermosetting translucent resin body for sealing a part of the chip mounting lead frame and the optical chip, and the translucent resin. An optical device comprising a thermoplastic light-shielding resin body for encapsulating an optical resin body, wherein the chip mounting of the optical chip is mounted on a portion of the chip mounting lead frame sealed by the translucent resin body. An optical device having a substantially U-shaped through hole so as to surround a surface of the lead frame for use in the direction of drawing and a surface perpendicular to the surface. 2. An optical chip, a chip mounting lead frame on which the optical chip is mounted, a thermosetting translucent resin body for sealing a part of the chip mounting lead frame and the optical chip, and the transparent member. In an optical device comprising a thermoplastic light-shielding resin body for encapsulating an optical resin body, at least the chip of the optical chip is provided in a portion of the chip mounting lead frame sealed with the translucent resin body. An optical device comprising a notch for covering a surface of a mounting lead frame corresponding to a pull-out direction. 3. The cutout is substantially L-shaped so as to surround a surface of the optical chip corresponding to a direction in which the chip mounting lead frame is pulled out and a surface perpendicular to the surface. Item 2. The optical device according to item 2.