JP2000091995A - Optical coupler - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make an optical coupler low in cost and small in size by using a remote controller which receives and sends a light signal and providing a plastic optical cable of a given length which has the other end coupled with a light emitting element or photoetector and a nearly cone-shaped recess which is formed at one end of the plastic optical cable. SOLUTION: This optical coupler 10 has the nearly cone-shaped recess 13 at one end 12 of the circularly-sectioned plastic optical cable 11. The nearly cone-shaped recess 13 while reflecting light arriving at right angles to the center line 14 of the plastic optical cable 11 transmits light from the center line 14. The photodetector is coupled with the other end side of the plastic optical cable 11. The optical coupler 10 is usable even for light emission. In this case, an infrared-light emitting diode(LED) is optically coupled with other end of the plastic optical cable 11. The light from the LED is transmitted along the center axis of the plastic optical cable 11, reflected by the surface of the nearly cone-shaped recessed part 13, and emitted at an angle of 270 deg..

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical coupler for transmitting and receiving data using light rays such as infrared rays.

[0002]

2. Description of the Related Art Generally, signals are transmitted by wired or wireless electric means.
For communication with a remote control (remote control) of an audiovisual device such as a television or a peripheral device of a personal computer, an infrared ray is emitted into the air and a signal is transmitted by light. This is convenient because it is not necessary to arrange a cable or the like between the operation unit and the transmitting / receiving end.

[0003] Communication using light rays such as infrared rays includes:
It is common to use an optical coupler. An example of a conventional optical coupler, in particular, a remote control light receiving section is disclosed in Japanese Utility Model Application Laid-Open No. 6-58636.
No. 6,086,045. In such a conventional optical coupler, a condensing lens is used but a conical reflector is used in order to have a wide range of incident angle characteristics.

[0004]

The above-mentioned conventional optical coupler has the following disadvantages. That is, the angle of incidence is limited because the reflector blocks incident light from above. For example,
When a conical reflector and a convex lens are used, incidence from the upper surface is impossible. Further, as another problem, the number of parts is inevitably increased because a convex lens or a reflector is attached, and the structure becomes complicated, resulting in an increase in cost.

An object of the present invention is to overcome the drawbacks of the conventional optical coupler and to provide an inexpensive and compact optical coupler.

[0006]

In order to solve the above-mentioned problems, an optical coupler according to the present invention employs the following characteristic configuration.

(1) In an optical coupler used for a remote controller or the like for inputting or outputting an optical signal, a plastic optical cable having a predetermined length and the other end coupled to a light emitting element or a light receiving element, and being formed at one end of the plastic optical cable. An optical coupler comprising a generally mortar-shaped recess.

(2) The optical coupler according to (1), wherein the surface of the substantially mortar-shaped concave portion of the plastic optical cable is rough.

(3) The optical coupler according to (1) or (2), wherein a substantially hemispherical protective cover is provided at the one end of the plastic optical cable.

(4) The optical coupler according to (1) or (2), wherein a substantially spherical protective cover is provided at the one end of the plastic optical cable.

(5) The optical coupler according to (3) or (4), wherein the optical signal is an infrared ray, and the protective cover is made of a material that is impermeable to visible light.

[0012]

Embodiments of the present invention will be described below with reference to the accompanying drawings. 1 to 3
It is the schematic which each shows another example of embodiment of the optical coupler of this invention.

First, a first embodiment of the optical coupler of the present invention will be described with reference to FIG. The optical coupler 10 is constituted by a plastic optical cable 11 having a circular cross section. This plastic optical cable 11 is well known,
Existing products that are commercially available from many manufacturers at relatively low cost are acceptable. This specific optical coupler 10 has a concave portion 13 in which one end 12 of a plastic optical cable 11 is processed into a mortar shape (that is, an inverted conical shape). The surface of the recess 13 is preferably rough. This mortar-shaped recess 13 reflects light from a direction perpendicular to the center line 14 of the plastic optical cable 11 and
The light from the direction 4 is transmitted. In addition, since the reflection includes diffuse reflection, it can be understood that the light can be incident from an angle that is somewhat away from the above-described perpendicular direction. For example, when the incident angle parallel to the center line 14 is 0 degree, about 13
Up to about 5 degrees, that is, a total of about 270 degrees of incidence is possible.

Although not shown, a light receiving element such as a photodiode or a phototransistor is optically coupled to the other end of the plastic optical cable 11 as a matter of course. The light receiving signal of the light receiving element is amplified as necessary, and a known process is performed in a receiving circuit.

The optical coupler 10 shown in FIG. 1 can be used not only for the above-described light reception but also for light emission. In that case, an infrared light emitting diode (LE
D) is optically coupled. The light from the LED is transmitted along the central axis 14 of the plastic optical cable 11, is reflected by the surface of the mortar-shaped recess 13, and is emitted at an angle of about 270 degrees as described above. Will understand.

When such an optical coupler 10 is used, it can be applied to, for example, a remote control light receiving section of an air conditioner (air conditioner) by effectively utilizing the wide incident angle as described above. In such a case, it is possible to perform control substantially without blind spots only by projecting the plastic optical cable 11 of the optical coupler 10 several cm from the air conditioner body.

Next, another embodiment of the optical coupler of the present invention will be described with reference to FIG. The optical coupler 20 is substantially the same as the plastic optical cable 1 of the optical coupler 10 of FIG.
One end 12 is provided with a protective cover 21 made of, for example, a hemispherical infrared transmitting material. According to the optical coupler 20, even if the optical coupler 20 is made to protrude outside from the air conditioner main body as described above, dust and the like are accumulated in the mortar-shaped concave portion 13 of the plastic optical cable 11, and the deterioration of the light transmission characteristic can be effectively prevented. It also becomes an accent on the design. When the hemispherical protective cover 21 is used, incident light of 360 degrees in the horizontal direction and at least 180 degrees in the vertical direction can be effectively incident. When a visible light opaque material is used as the material of the protective cover 21, the S / N ratio of the optical coupler 20 can be improved.

Next, a third embodiment of the optical coupler of the present invention will be described with reference to FIG. This optical coupler 30 has a configuration in which a spherical protective cover 31 made of an infrared transmitting material is formed on one end 12 of a plastic optical cable 11. This spherical body may be made into a spherical shape by heating and melting the tip itself of the plastic optical cable. Even in the optical coupler 30, the light can be incident / emitted at about 270 degrees in the vertical direction.

Although the preferred embodiment of the optical coupler of the present invention has been described above, it can be understood that various modifications can be made in accordance with a specific application.

[0020]

As can be understood from the above description, according to the optical coupler of the present invention, a mortar-shaped concave portion capable of reflection and transmission is formed at one end of a plastic optical cable and can be reflected at the surface thereof. Extremely wide angle of incidence (wide angle)
Is obtained. Further, the optical coupler of the present invention forms a mortar-shaped recess at the tip of the plastic optical cable,
Since the protective cover is simply attached as required, the structure is simple, extremely inexpensive, and durable, so that it has a remarkable effect in practical use.

[Brief description of the drawings]

FIG. 1 is a side view of a first embodiment of an optical coupler according to the present invention.

FIG. 2 is a side view of a second embodiment of the optical coupler of the present invention.

FIG. 3 is a side view of a third embodiment of the optical coupler of the present invention.

[Explanation of symbols]

 10, 20, 30 Optical coupler 11 Plastic optical cable 12 One end 13 Substantially mortar-shaped recess 21, 31 Protective cover

Claims (5)

[Claims] An optical coupler for use in a remote controller or the like for inputting or outputting an optical signal, comprising: a plastic optical cable having a predetermined length coupled to a light emitting element or a light receiving element at the other end; and one end of the plastic optical cable. An optical coupler comprising a substantially mortar-shaped recess. 2. The plastic optical cable according to claim 1, wherein the surface of said substantially mortar-shaped recess is rough.
An optical coupler according to claim 1. 3. The optical coupler according to claim 1, wherein a substantially hemispherical protective cover is provided at the one end of the plastic optical cable. 4. The plastic optical cable according to claim 1, wherein a substantially spherical protective cover is provided at said one end.
Or the optical coupler according to 2. 5. The optical signal according to claim 3, wherein the optical signal is infrared light, and the protective cover is made of a visible light opaque material.
Or the optical coupler according to 4.