JPH04129874A - Light space transmission device - Google Patents

Abstract

PURPOSE:To improve the reliability of communication by composing a light transmitter/ receiver on a fixed body and a light transmitter/receiver installed on a side surface of a movable body facing this light transmitter/receiver having a light emitting beam and a light receiving field of view diffused at a proper angle to the advance direction of the movable body respectively. CONSTITUTION:When a light transmitter/receiver 4 on a movable body gets close to a light transmitter/receiver 5 on a fixed body, a light source for transmitting a light space is lighted just before a time when transmission is or becomes possible till just after the time, or when the light transmitter/receiver 4 for the movable body gets close to the light transmitter/receiver on the fixed body side 5, a light space transmission light signal is received to light the light source for light space transmission for the light transmitter/receiver on the movable body side, so a light signal is emitted. At this time, an emitted light beam and a receiving field of views of the light transmitter/receivers 4, 5 on the movable body side and the fixed body side are wide, transmission is possible if a stop position of the movable body 1 is deflected, and a light transmission distance can be very short, so the light receiving strength can be large, and that effects of disturbance can be eliminated. The reliability of communication can thus be improved.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an improvement in an optical space transmission device related to data transmission technology between a moving body such as a train and a fixed body on the ground side.

[Conventional technology]

Infrared light emitting diodes and semiconductor lasers are generally used as light sources for optical space transmission devices that communicate data between moving objects such as trains and fixed objects such as platforms, but these light sources have low output. .

For this reason, on the light emitting side, an optical system such as a lens is used to narrow down the light beam and direct most of the emitted light toward the light receiving side.On the light receiving side, a large diameter optical system is used to narrow down the emitted light. Efforts have been made to capture as much light as possible, and in this way, conventional optical space transmission devices are put into practical use by narrowing the emitted light beam and limiting the light receiving field of view. However, in the case of an equipment configuration in which the optical axis of the emitted light beam and light receiving field of optical space transmission is approximately perpendicular to the traveling direction, the stopping position of the moving object may be This has the disadvantage that if the signal is misaligned, transmission will not be possible.

Therefore, in general, in the case of optical space transmission between the train 50 and the fixed body side 51, the emitted light beam B is narrowed and the light receiving field E is also narrowed as described above, so the emitted light beam B and the light receiving field E are made to match. For simplicity, as shown in FIG.
The equipment is arranged so that it is approximately parallel to the

[Problem to be solved by the invention]

However, in such a configuration, the installation on the fixed body side must be arranged so that it does not interfere with train operation, so train 5
Emitter/receiver 52 on the 0 side and emitter/receiver 53 on the fixed body side 51
The distance β becomes from 50 m to 100 m.

In addition, in this type of optical space transmission device, the emitter/receiver 52 for the moving body is installed in the driver's seat at the head of the train 50, and the emitter/receiver 53 for the fixed body is installed on the side of the track 54. As a result, equipment not necessary for train operation was installed in the driver's seat, obstructing part of the driver's field of view, which was not desirable for safe driving. The front of the train is directly affected by the weather, with rain and snow adhering to the window glass, which attenuates or blocks the emitted light from the optical space transfer device. (However, the visibility of the optical space transmission device is not guaranteed.)
Therefore, it is not the best place to install it.

In addition to installing it in the driver's seat, it is also possible to install it under the floor, but in this case, since the optical space transmission device on the fixed body side is installed at a low position, it may be exposed to adverse environmental atmospheres such as iron content peculiar to railways. It has been undesirable to perform spatial optical transmission in the direction of travel due to the problems associated with this.

The present invention was created in view of the above problems,
It is an object of the present invention to provide an optical space transmission device that has a short communication distance and excellent communication performance, and is also economical in terms of installation space and operating costs.

[Means to solve the problem]

In order to achieve the above object, the optical space transmission device according to the present invention includes a light emitter/receiver on the fixed body side and a light emitter/light receiver attached to the side surface of the moving body opposite to the emitter/light receiver, respectively. The gist of the present invention is to configure an optical space transmission system that has a light emitting beam and a light receiving field that are diffused at an appropriate angle in the direction of movement of a moving body, and that connects the two light beams and the light receiver using a luminous flux signal. .

Then, the emitting/receiving device on the moving object side and the emitting/receiving device on the fixed object side.
The light receiver is constructed by combining a light-emitting element with a condensing optical system such as a cylindrical lens, each consisting of a light-emitting element and a lens capable of obtaining an appropriate emission angle, or by arranging a plurality of light-emitting elements in parallel in the direction of movement of the moving body. The light distribution is configured such that the light distribution is long, and in the light receiver, the light receiving area is limited by a light receiving element and a field stopper (diaphragm), or an optical system such as a cylindrical lens, and the light is transmitted to the moving object facing the light emitter. The gist is to configure a light-receiving field of view that becomes longer in the direction of travel.

In addition, the optical space transmission device according to the present invention is capable of transmitting light in space from immediately before to immediately after the time when transmission is possible or becomes possible when the light emitter/receiver on the moving body approaches the emitter/receiver on the fixed body. When the light source of the mobile object is turned on, or when the light emitter/receiver for the mobile object approaches the emitter/receiver of the fixed object, the mobile object receives an optical space transmission optical signal from the emitter/receiver of the fixed object. It is preferable to adopt an optical space transmission method in which a light source for optical space transmission in the transmitter/receiver is turned on.

Note that the detection of the state in which the "emitting device/receiver on the movable object is close to the emitting/receiving device on the fixed object" described here can be performed using the train approach signal at the station, which has been used in the past.

Effect C] The above-mentioned optical space transmission device operates as a light source for optical space transmission when the light emitter/receiver on the moving body approaches the light emitter/receiver on the fixed body, at the time when transmission is possible, or from immediately before to immediately after the time when transmission becomes possible. or when the mobile body's emitter/receiver approaches the fixed body's emitter/receiver, the mobile body receives the optical space transmission optical signal from the fixed body's emitter/receiver and The light source for optical space transmission in the receiver is turned on to emit an optical signal.

At this time, because the emitted light beam and the light receiving field of the light emitting and receiving devices on the moving object side and the fixed object side are wide, transmission is possible even if the stopping position of the moving object is shifted, and the optical transmission distance can be dramatically shortened. Therefore, it becomes possible to increase the received light intensity (the reaching energy of an optical signal is inversely proportional to the square of the distance) and easily eliminate the effects of disturbance, improving the reliability of communication = 6 can.

〔Example〕

An embodiment of the optical space transmission device according to the present invention will be described below with reference to FIGS. 1 to 4.

In the drawing, 1 is a train running on a track 3 laid along a platform 2, with the train 1 on the moving body side and the platform 2
A light receiver 4 is installed on the moving body and a light receiver 5 is installed on the fixed body side.

The moving body side light receiver 4 is fixedly installed, for example, on the upper side of the train car near the door lock confirmation light 6, and the fixed body side light receiver 5
are fixedly mounted opposite to each other at a height that does not interfere with passengers getting on and off the platform 2 near the mounting locations of the destination guide board 7, speakers, etc.

Both light emitters and light receivers 4 and 5 (see Figure 4) obtain a light emitting beam B and a receiving field of view E that are wide in the horizontal direction and narrow in the vertical direction, respectively, so the light emitter 8 is shown in Figure 2 (a). Light emitting element 9
An optical system consisting of a cylindrical lens 10 is placed on the front optical axis of the optical system to form a horizontally long optical pattern P1 as shown in FIG. 2 fbl.

In addition, in FIG. 3(al), a plurality of light emitting elements 9, 9... are arranged in parallel in the horizontal direction to form a horizontally long optical pattern P2 as shown in FIG. 3(b).11 is a light receiver. The light receiver 11 forms a field stopper (aperture) 13 on the optical axis in front of the light receiving element 12.

At this time, the spread angle θ2 of the light-receiving field of view can be set by changing the distance Ill between the light-receiving element 12 and the field stopper 13, or by changing the width I12 of the aperture 14 of the field stopper 13. Similarly to the light emitter, a desired light receiving field can also be obtained in the light receiver by using a cylindrical lens as shown in FIG.

That is, according to the above configuration, the emitted light beam B and the light-receiving field of view E spread in the running direction F of the train at an angle θ1. θ2, and such an optical configuration that is wide in the horizontal direction and narrow in the vertical direction has a distance (about 2 to 3 m) that can cover the stopping error of the moving object in the horizontal direction, and a distance that can cover the stopping error of the moving object in the vertical direction. It is sufficient to have an emitted light beam and a wide light receiving field that can correspond to the tilting angle or the vertical movement distance (In degree). This enables optical space transmission between train 1 and platform 2, and the transmission distance is shorter than previous optical space transmission devices.
It is 3-6m.

This optical transmission distance is approximately 1/1 of the optical transmission distance (50 to 100 m) under installation conditions like conventional optical space transmission equipment (optical system oriented approximately parallel to the direction of travel).
Therefore, the received light intensity increases approximately 100 times.

〔Effect of the invention〕

Since the optical space transmission device according to the present invention is configured as described above, the optical transmission distance is dramatically greater than the optical transmission distance when the optical system is oriented so that the communication direction is approximately parallel to the traveling direction of the moving object. Since the length can be made shorter, the received light intensity can be increased, and the influence of disturbance can be easily eliminated, thereby improving the reliability of communication. In addition, by limiting the communication time, the service life can be extended compared to keeping the light source on all the time, and heat generation can be suppressed, which increases the reliability of electronic components and equipment. It is possible to improve the reliability of the light source and save power. Furthermore, if a condensing optical system such as a lens is not used, not only will there be no effects of burnout due to sunlight, etc., but the emitted light beam and light receiving field of view will be wide, so even if the stopping position of a moving object such as a train shifts, it will not be affected by sunlight. The present invention has the characteristics of being able to transmit and easily adjust, and the effects of the present invention are extremely large.

[Brief explanation of drawings]

Fig. 1 is a schematic plan view (a) and an elevational view fb) showing the principle of the optical space transmission device according to the present invention, and Fig. 2 is a plan cross-sectional view fa showing an embodiment of the light emitting device of the emitter/receiver. ) and an explanatory diagram (b) showing the light distribution pattern, and FIG. 5 is a plan sectional view showing an embodiment of the light receiver, and FIG. 5 is a schematic diagram showing the principle of a conventional optical space transmission device. 1...Train 2...Platform 3...Track 4. ...How many shots from moving objects?Receiver 5...How many shots from fixed objects?Receiver 6...Door lock confirmation light 7...Destination information board 8...
Light emitter 9... Light emitting element 0... Cylindrical lenst... Light receiver 12... Light receiving element 3... Field stopper

Claims (1)

[Claims] A light emitter/receiver on the fixed body side and a light emitter/receiver mounted on the side surface of the movable body opposite to the emitter/light receiver respectively detect the emitted light beam and the light receiving field that are diffused at appropriate angles in the traveling direction of the movable body. What is claimed is: 1. An optical space transmission device having an optical space transmission system, characterized in that when both the emitter and the light receiver face each other, the light emitted from each light receiver is received.