JPS62132377A - Photomicrosensor - Google Patents

Abstract

PURPOSE:To obtain a reflection type photmicrosensor adapted for a mass production with less irregularity as products by disposing light emitting element and photo receiving element chips on opposing lead frames, integrally molding them with a transparent resin, and forming a groove therebetween. CONSTITUTION:A light emitting diode chip 11 and a phototransistor chip 12 are bonded onto opposing lead frames 13, 14. A groove 16 is formed at the center of the ends of the lead frames 13, 14 formed with the chips 11, 12 by low pressure molding of transparent resin 15, and molded into U-shaped section. Thus, a light emitting from the chip 11 is transmitted through the resin 15 and a lens 17 to be emitted externally, and when an article 20 exists at a focal position, the reflected light is applied from the article through lens 18 to a phototransistor chip 12. Accordingly, since the light is supplied or interrupted/ according to the presence or absence of the article, the article can be detected by the output of the chip 12.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of the Invention] The present invention relates to a reflective photomicrosensor in which a light-emitting element chip and a light-receiving element chip are enclosed in the same package and detect an object using reflected light.

[Summary of the invention]

In the photomicrosensor according to the present invention, chips of a light emitting element and a light receiving element are formed on opposing lead frames, molded with transparent resin, separated by a groove in the center, and objects are detected depending on the presence or absence of reflected light. It is a photomicrosensor for detection.

[Prior art and its problems]

Conventionally, a reflective photosensor is known in which a light emitting element such as a light emitting diode and a light receiving element such as a phototransistor are molded into separate elements, and then assembled into one case. In such conventional reflective photosensors, the positioning of the light emitting and receiving elements is determined by the mounting position on the case, which causes problems such as the structure of the case being complicated and the position of the light emitting and receiving elements tending to vary. there were. Furthermore, since it is necessary to mold the light emitting element and the light receiving element separately, there is a problem in that the manufacturing process is time-consuming and the assembly workability is poor.

Therefore, a photomicrosensor in which a light emitting/receiving element is enclosed in the same package is also known. FIG. 2 is a perspective view showing such a conventional photomicrosensor, in which a light-emitting diode chip 2 and a phototransistor chip 3 are provided in a pan cage 1, both ends of each chip are connected to a lead fI4, and a light-shielding wall is provided. The light emitting and receiving parts are separated by a cap 5 having a transparent resin 6 on the top surface of the cap 5.
It is configured by providing. Such a reflective photomicrosensor can improve positioning accuracy, but it is difficult to form a lens on the top surface of the light emitting/receiving element, and productivity is poor because it does not use a lead frame. There was a problem.

[Purpose of the invention]

The present invention has been made in view of the problems of conventional reflective photomicrosensors, and is a photomicrosensor that can be easily manufactured by integrally molding a light emitting and receiving element on a transparent resin. The purpose is to provide sensors.

[Structure and effects of the invention]

The present invention is a reflective photomicrosensor that irradiates light from a light emitting element chip to the outside and detects an object based on the presence or absence of the reflected light using a light receiving element chip. This device is characterized in that a bonded light emitting element chip and a light receiving element chip are integrally molded in a transparent resin, and a groove is provided in the center of the transparent resin.

According to the present invention having such features, the chips of the light emitting element and the light receiving element are disposed on opposing lead frames and integrally molded with transparent resin, and a groove is provided between them. The object is detected when the light from the chip is reflected by the object and applied to the light receiving element chip. In this way, the position, angle, etc. of each chip are defined during molding, so variations can be extremely reduced. Furthermore, since the manufacturing process is significantly reduced, it is possible to reduce the price through mass production.

When the photomicrosensor is housed in a case, it is not necessary to specify the positions of the light emitting and receiving elements, making manufacturing extremely easy. Furthermore, there is no need to use a case even when used under conditions with little ambient light (this makes it possible to construct the device only by encapsulation molding with transparent resin, making it possible to significantly reduce the price).

[Explanation of Examples]

FIG. 1 is a longitudinal sectional view and an elevational view showing an embodiment of a photomicrosensor according to the present invention. In this figure, a light emitting diode chip 11 and a phototransistor chip 12 are bonded and formed on lead frames 13 and 14, respectively. And a lead frame 1 on which a light emitting diode chip 11 and a phototransistor chip 12 are formed.
The tip of 3.14 is molded into a U-shaped cross section with a groove 16 in the center by low-pressure molding with transparent resin 15. The lead frames 13 and 14 are not arranged in a straight line,
In order to allow the light emitted from the light emitting diode chip 11 to be reflected by an object and applied to the phototransistor chip 12, the light emitting diode chip 11 is arranged at an obtuse angle as shown in the figure. The groove 16 separates the light from the light emitting diode chip 11 in the center so that it does not directly pass through the resin and reach the phototransistor chip 12. A lens 1 is placed on the light emitting diode chip 11 and the phototransistor chip 12 on the transparent resin 15, respectively, as shown in the figure.
Form 7.18. Further, it is preferable to form fine anti-reflection grooves 19 on the lower surface of the transparent resin 15 in order to prevent total reflection.

Since a case is not necessary in a state where there is little disturbance light, the photomicrosensor molded from transparent resin 15 is used as is, and lead frame 13.1 is attached as needed.
4 as shown by the broken line in the figure. Then, the light emitted from the light emitting diode chip 11 passes through the transparent resin 15 and the lens 17 and is irradiated to the outside, and if there is an object 20 at the focal position, the light reflected from it passes through the lens 17. applied to the phototransistor chip 12.

Therefore, since the light is interrupted depending on the presence or absence of an object, it is possible to use a reflective photomicrosensor that detects an object based on the output from the phototransistor chip 12.

In this way, since a lead frame is used, the manufacturing process can be significantly reduced, and a photomicrosensor in which a light emitting diode chip and a phototransistor chip are arranged with high positioning accuracy can be constructed.

In this embodiment, the transparent resin 15 was used as is, but when used in an environment where there is a possibility of incident disturbance light,
This photomicrosensor may be used by being enclosed in a predetermined case. In this case, as in the conventional example described above, insert a light-shielding plate into the groove provided in the center of the transparent resin 15 as shown by the broken line, and the light from the light-emitting diode chip 11 will pass through the direct phototransistor chip. 12, making it possible to improve the reliability of object detection.

[Brief explanation of drawings]

FIG. 1 is a sectional view showing an embodiment of a photomicrosensor according to the present invention, and FIG. 2 is a perspective view showing an example of a conventional photomicrosensor. 1-...Package 2, 11--------
-Light emitting diode chip 3.12-...-Phototransistor chip 6,15--Transparent resin 13.14--Lead frame 17
．． 18-------- Lens 19-- Anti-reflection groove Patent applicant Tateishi Electric Co., Ltd. Agent Patent attorney Kanki Okamoto (and one other person) Figure 1 11-- -Emitted diode +,, de12--
---・-Phototransistor Star No., 1B, 14-
---- 'J-do frame 15----------Transparent needle 11ft 19・--1----- Figure 2

Claims (3)

[Claims] (1) A reflective photomicrosensor that irradiates light from a light-emitting element chip to the outside and detects an object based on the presence or absence of reflected light using a light-receiving element chip. A photomicrosensor characterized in that a bonded light-emitting element chip and a light-receiving element chip are integrally molded in a transparent resin, and a groove is provided in the center of the transparent resin. (2) The photomicrosensor according to claim 1, wherein the transparent resin has fine anti-reflection grooves formed on its lower surface. (3) The photomicrosensor according to claim 1, wherein the transparent resin has a lens formed above the light emitting element chip and the light receiving element chip.