JPH0142360Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a light emitting semiconductor device having directivity in two directions.

A resin-sealed light emitting diode with directivity that has been put into practical use is shown in FIGS. 1 and 2. In both figures, 1 is a light emitting diode chip,
2a and 2b are lead frames to which the light emitting diode chip 1 and wires are bonded, and these are sealed with a resin 3 having translucency.
Here, the resin 3 that seals the light emitting diode chip 1 has a curvature to obtain a lens effect in order to output the light emitted from the light emitting diode chip 1 with sharp directivity in a specific direction. A bulge 4 is formed.

The light emitting diode having the above structure has been widely put into practical use as a photointerrupter, in which a device is placed in a facing relationship with a light receiving element such as a phototransistor so that their optical axes coincide with each other, and detects a blocking object that crosses the optical axis.

This type of shielding object detection device is used as a means for supplying input information by being combined with various electronic devices. Although it is necessary to simultaneously detect objects on the optical axis extending in two directions from the photointerrupter, when installing the photointerrupter in a device that does not have enough space to install two sets of photointerrupters, it is necessary to detect objects on the optical axis extending in two directions. A neutral tungsten lamp 5 is used as a light source,
Phototransistors 6 and 7 are arranged to perform object detection. Therefore, not only is it necessary to align the light source and the light receiving element, but also a tungsten lamp is used as the light source, which makes it difficult to use a semiconductor, which is undesirable from the viewpoint of power consumption.

The present invention improves the drawbacks of the conventional devices described above and provides a light emitting semiconductor device that can extract directional output light in two directions shifted by a predetermined angle from one light emitting semiconductor chip by simply adding a simple configuration. do. Next, the present invention will be explained in detail with reference to examples.

FIG. 4 is a top view of an embodiment according to the present invention, and FIG.
The figure is a front cross-sectional view, and FIG. 6 is a cross-sectional view taken along line A-A' in FIG.

A light emitting diode chip 1 in which a PN junction, electrodes, etc. are formed using conventionally known semiconductor technology is placed on the upper end surface of one lead frame 2a, and the PN junction light emitting surface of the chip 1 is parallel to the upper end surface of the lead frame 2a. In other words, the light emitted from the PN junction light emitting surface of the chip 1 reaches the lead frame 2a.
It is bonded so that it spreads out in a plane that is almost perpendicular to the length direction. Wire bonding is performed between the upper surface electrode of the chip 1 and the end surface of the other lead frame 2b. Here, the upper surface electrode is provided to cover the entire surface of the chip 1, and is intended to increase the light emitted from the PN junction on the side surface.

A light emitting diode chip 1 bonded to a lead frame is sealed with a transparent resin 8, and lenses 8a and 8b are integrally formed in the resin 8 to give directionality to the emitted light. The positional relationship between the light emitting diode chip 1 and the optical axes of the lenses 8a and 8b is such that they are offset from the optical axes of the lenses 8a and 8b, as shown in FIG.

That is, the light emitting diode chip 1 on the upper end surface of the lead frame 2a and the entire upper part of each lead frame 2a, 2b are sealed with a transparent resin 8, and the resin 8 includes the PN on the side surface of the light emitting diode chip 1. Lenses 8a and 8b that provide directivity in two opposite directions perpendicular to the plane formed by the lead frames 2a and 2b around the joint portion.
are integrally formed, and the light emitting diode chip 1 is arranged at a position offset from the optical axis of the lenses 8a and 8b.

With such a configuration, light beams shifted by a predetermined angle in a well-balanced manner in two directions can be obtained by simply arranging the lenses 8a and 8b of the light emitting diode chip 1 so as to be offset from the optical axes of the lenses 8a and 8b during resin sealing. For example, VTR
The light source for detecting the tape end detects the end of the tape using two light-receiving elements arranged at positions shifted by a predetermined angle in both directions from the light source. It can be matched with the optical path for tape end detection.

Further, the light emitting diode chip 1 is mounted and bonded with the PN junction light emitting surface positioned almost parallel to the chip mounting surface on the upper end surface of one lead frame 2a, and the other electrode and the other lead frame 2b are connected with wires. However, since the lenses 8a and 8b are provided in two opposite directions perpendicular to the plane made up of the lead frames 2a and 2b, the wire connecting the other electrode of the light emitting diode chip 1 and the lead frame 2b focuses the light. There is no interference, and more uniform light output can be obtained from the lenses 8a and 8b.

Furthermore, when sealing with resin, the lead frame 2a,
It is convenient to use upper and lower (or left and right) molds that sandwich lead frames 2b, but in such a case, if lenses 8a and 8b are formed in a direction perpendicular to the plane formed by lead frames 2a and 2b During sealing, resin burrs do not occur on the lens portions 8a and 8b, and lens portions 8a and 8b with better directivity can be easily formed.

Furthermore, the parts other than the lenses 8a and 8b are formed on flat surfaces, so that the emitted light can be effectively led out from only the lenses 8a and 8b, giving higher directivity to the output light.

As described above, according to the present invention, it is possible to obtain light beams shifted by a predetermined angle in two directions in a well-balanced manner with one light emitting semiconductor device, and the wire to the other lead terminal does not get in the way, and light emission is uniform in each direction. In addition to being able to obtain output, it also has the advantage of being able to easily form lenses with excellent directivity without the generation of burrs when resin-sealed. The light source can be used as an input device for electronic equipment, etc., and can be a light source with low power consumption, long life, and high reliability.

Furthermore, the present invention has a flat surface except for the lens portion, and can effectively guide the emitted light to the outside using only the lens portion, thereby providing higher directivity.

[Brief explanation of the drawing]

1 and 2 are cross-sectional views of a conventional device, FIG. 3 is a schematic diagram of a conventional shielding object detection device, and FIGS. 4, 5, and 6 are top views of an embodiment according to the present invention,
They are a side view and an A-A' side sectional view. 1: Light emitting diode chip, 2a, 2b: Lead frame, 8: Resin, 8a, 8b: Lens.

Claims (1)

[Scope of utility model registration request] In a light emitting semiconductor device having two lead terminals and having these lead terminals led out in parallel in the same direction, a chip mounting surface is provided on the upper end surface of one of the lead terminals, and the chip mounting surface is substantially parallel to the chip mounting surface.
The light emitting element chip is mounted and bonded with the PN junction light emitting surface positioned, the other electrode and the other lead terminal are connected with a wire, and a transparent layer is formed so as to cover the entire upper part of the light emitting element chip and the lead terminal. The light emitting element chip is sealed with a resin, and lens portions are formed around the side surfaces of the light emitting element chip in the sealing resin to provide directivity in two opposite directions perpendicular to the plane formed by the two lead terminals, and 1. A light emitting semiconductor device, wherein the other portions except the lens portion are formed on a flat surface, and the light emitting element chip is arranged offset from the optical axis of both the lens portions.