JP2003209520A - Transmitter, receiver and signal axis alignment method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To easily and accurately align a signal axis and to efficiently transmit and receive signals in a transmitter performing radio communication of information such as an infrared ray transmitter. <P>SOLUTION: The transmitter 1 changes only directivity without changing the optical axis direction of an infrared ray light. First, the infrared ray light 13 of wide directivity is sent out from the transmitter 1, and in order to make a receiver 2 receive the infrared ray light at or above a prescribed allowable level, the positions and directions of each other are adjusted (first optical axis adjustment). Then, the infrared ray light 12 of narrow directivity is sent out from the transmitter 1, and in order to make the receiver 2 receive the infrared ray light at or above the prescribed allowable level, the positions and directions of each other are adjusted (second optical axis adjustment). Though the directivity of the infrared ray light is narrow in the second adjustment, since rough optical axis alignment is already completed by the first adjustment, the optical axis is easily aligned. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a transceiver for wireless communication, and more particularly to a technique for facilitating signal axis alignment between a transmitter and a receiver constituting a wireless transmitter.

[0002]

2. Description of the Related Art Conventionally, as one type of wireless communication, there is an optical communication technique for spatially transmitting information using light. In this optical communication, infrared light is generally used as a transmission signal,
As the light emitting element, a semiconductor light emitting element such as a light emitting diode or a laser diode is used. In such optical communication, in order to secure a sufficient distance between transmission and reception, it is necessary to sharply narrow the directivity of the light beam emitted from the transmission device so that a sufficient light level is incident on the reception device side. Therefore, it is necessary to match the optical axes (signal axes) of the transmitter and the receiver, but use a light beam with a narrow directivity or use infrared light whose light beam is invisible. From the above, alignment of the optical axes of the transmitter and receiver is a very troublesome work. Therefore, conventionally, there has been proposed a transmission / reception device for optical wireless communication which can easily perform the optical axis alignment.

As one example thereof, visible light reflected from a transmitter is narrowed down to a pinpoint and sent together with infrared light for signal transmission along the same optical axis or parallel optical axis, and provided on the receiver side. Japanese Unexamined Patent Publication No. 62-110339 discloses a transmitting / receiving device which adjusts the direction of the transmitting device while the operator views the visible light reflected by the visible light reflecting means. In addition, as another technique, a sighting device is installed in the transmission device, and a transmitting and receiving device that aligns the optical axis while looking at the sighting device, or a measuring device for detecting the received light level is connected to the receiving device side There is also a transmitter / receiver that aligns the optical axes.

Further, FIG. 11 is a diagram of Japanese Unexamined Patent Publication No. 6-232818.
FIG. 3 is a diagram for explaining the principle of an optical axis alignment method in a transceiver for optical wireless communication disclosed in Japanese Patent Publication. In the figure, reference numeral 101 is a transmitter for optical communication, which is an infrared light 104 (hereinafter, referred to as a first optical signal corresponding to a first electric signal) having a narrow directivity with a full width at half maximum of about 1 degree. 1 transmitted light 10
4) is output from the first light emitting element 107a and has a wider directivity than the first transmission light 104 having a full width at half maximum of about 5 degrees, which is a second optical signal corresponding to the second electric signal. The light 105 (hereinafter referred to as the second transmission light 105) is
The light is emitted from the light emitting element 7b.

The irradiation area 108 of the first transmitted light 104 is
As shown in the figure, the irradiation area 109 of the second transmission light 105
It is set to illuminate the inside. Further, the optical axis of the first transmission light 104 shown in FIG.
Since it is aligned with the optical axis of the first transmission light 104, the irradiation area 108 of the first transmission light 104 can be easily found by monitoring the radiation intensity distribution of the second transmission light 105.

Reference numeral 102 denotes a receiver for optical communication, which has a light receiving element 110, and converts the light received by the light receiving element 110 into an electrical signal to be an output signal. This receiving device 10
Reference numeral 2 indicates that the optical signal received by the light receiving element 110 is separated into an electric signal of the first transmission light 104 and an electric signal of the second transmission light 105 by using a bandpass filter, and transmitted by each optical signal. Information is converted into an electric signal and used as an output signal. 103 is a monitor TV capable of displaying a video output according to an output signal from the receiving apparatus 102.

Next, the transmitter 101, the receiver 102,
An optical axis alignment method using the monitor TV 103 will be described. When optical communication is performed indoors, etc., the transmitter 10
1. Since the distance of the receiving device 102 is at most about several tens of meters, by visually determining the direction of the transmitting device 101, the irradiation area of the second transmission light 105 capable of irradiating a wide range is
The light receiving element 110 of the receiving device 102 can be easily set. At this time, the second transmission light 10 is displayed on the monitor TV 103.
A coarse adjustment level image showing the irradiation level of No. 5 is displayed.
Next, the direction of the transmitter 101 is adjusted while watching the irradiation level displayed on the monitor TV 103, and the second transmitted light 105
Of the most radiant intensity, that is, the central part of the
10 so that it is irradiated.

Next, when the light receiving element 110 is irradiated with the central portion of the second transmitted light 105, the light receiving device 10
The output of No. 2 is switched to the output of the first transmission light 104. As described above, since the irradiation area of the first transmission light 104 is set to exist in the central portion of the irradiation area of the second transmission light 104, at this time, the light receiving element 110 causes the first transmission light 104 to be irradiated. It is in the irradiation area of. Next, monitor TV1
When the display of 03 is switched to the first transmission light 104, the first
The image information transmitted by the transmission light 104 or the image showing the radiation intensity of the first transmission light 104 is displayed. next,
While watching the display on the monitor TV 103, the first transmission light 104
So that the radiation intensity of the
So that the video information displayed on the screen is the best.
The direction of 01 is further finely adjusted. When the video information displayed on the monitor TV 103 becomes the best, the transmitting device 101
Then, the optical axis alignment with the light receiving device 102 is completed.

[0009]

By the way, the transmission / reception apparatus as disclosed in the above-mentioned Japanese Patent Laid-Open No. 62-110339 requires a configuration for causing the transmission apparatus to generate visible light used for purposes other than the purpose of optical transmission. I am trying. When it is desired to maintain a sufficient distance between the transmitter and receiver, the emission output of this visible light must be sufficiently large, and the configuration must be added, which increases the cost of the transmitter. Besides, the device becomes large in size. This is also the case when the sighting device is installed in the transmitter. Further, it is necessary to strictly align the optical axis of visible light, the sight of the sighting device, and the optical axis of infrared light for signal transmission, which also causes a cost increase. Further, even when the light receiving level detecting measuring device is connected to the receiving device and performed by two persons, there are drawbacks such that it is necessary to prepare the light receiving level detecting measuring device and labor is required.

As described above, in the conventional transmitter / receiver for optical communication, if the optical axis alignment is attempted to be simplified, the transmitter / receiver cost will increase and the size will increase, and the transmitter / receiver cost will decrease and the size will decrease. However, there has been a drawback in that the work of aligning the optical axes is troublesome.

Further, the transceiver for optical wireless communication shown in FIG. 11 is intended to solve this problem. However, even in this configuration, since the second light emitting element 107b for optical axis alignment is used in addition to the first light emitting element 107a for transmitting the transmission information signal, the first transmission light 104 and the second transmission light are used. The optical axis with 105 does not exactly match.

On the other hand, in the device on the receiver side, for the purpose of facilitating the optical axis alignment, the receiver can receive the signal from the transmitter so that the infrared light can be received from a wide angle. The range of the incident angle (defined as "reception angle" in the present specification, and particularly, the range of the incident angle at which the light receiving element in the receiver of the infrared transmission device can receive light is referred to as "reception angle") is widened. There was a need. However, if the light receiving angle of the light receiving element is widened, the optical axis alignment becomes easier, but the reception efficiency of the incident light is reduced. Also,
Since the light-receiving angle is wide, there is a problem that light other than the signal light emitted from the transmitter, such as sunlight or light from a lighting device, is likely to enter the light-receiving element and is easily affected by optical noise.

The above problem can be said to be a common problem not only in the infrared transmission device described above, but also in the transmission device for wireless communication using invisible transmission signals such as radio waves and ultrasonic waves.

The present invention has been made to solve the above problems, and in a transmission device for wireless communication of information including an infrared transmission device, signal axis alignment can be easily and accurately performed. Further, it is an object of the present invention to provide a transmitting device and a receiving device that are less likely to be affected by external noise and can efficiently transmit and receive signals, and a signal axis alignment method.

[0015]

A transmission device according to claim 1 is a transmission device for transmitting a transmission signal for wireless communication, the transmission signal generating means for generating the transmission signal, and the transmission signal. And directivity adjusting means for changing directivity.

According to a second aspect of the present invention, there is provided the transmitter according to the first aspect, wherein the transmission signal is infrared light, and the directivity adjusting means allows the infrared light to pass therethrough. It has a lens, and changes the directivity of the infrared light by changing the distance between the transmission signal generating means and the first lens.

According to a third aspect of the present invention, there is provided a receiving device for receiving a transmission signal for wireless communication, wherein the receiving means for receiving the transmission signal and the receiving angle of the receiving means are changed. And a reception angle adjusting means.

The receiving device according to claim 4 is the receiving device according to claim 3, wherein the transmission signal is infrared light, and the reception angle adjusting means collects the infrared light in the receiving means. It is characterized in that it has a second lens for emitting light, and changes the size of the reception angle by changing the distance between the receiving means and the second lens.

A receiving device according to a fifth aspect is the receiving device according to the third or fourth aspect, in which level detecting means for detecting an intensity level of the transmission signal received by the receiving means; Level display means for performing a display associated with the intensity level detected by the level detection means.

A signal axis aligning method according to a sixth aspect is a signal axis aligning method between a transmitting device and a receiving device for wireless communication, wherein (a) the directivity of a transmission signal transmitted by the transmitting device is normally set. And (b) performing a first adjustment for changing the position and direction of the transmitter and / or the receiver, and (c) transmitting the signal received by the transmitter. Steps (a) to ((a) through (d) comprising a step of bringing the directivity into the normal use state and a step (d) of performing a second adjustment for changing the position and direction of the transmitter and / or the receiver. d)
It is characterized in that the steps (a), (b), (c) and (d) are performed in this order.

A signal axis aligning method according to a seventh aspect is the signal axis aligning method according to the sixth aspect, wherein the transmission signal is infrared light, and the transmitting device generates infrared light. A light generation means and a first lens through which the infrared light passes; and the step (a) and the step (c) change the distance between the infrared light generation means and the first lens. It is performed by.

The signal axis aligning method according to claim 8 is a signal axis aligning method between a transmitter and a receiver for wireless communication, wherein (e) the receiving angle of the receiver is normally used. And (f) performing a third adjustment for changing the position and direction of the transmitting device and / or the receiving device, and (g) determining the size of the receiving angle of the receiving device. And (h) performing a fourth adjustment for changing the position and direction of the transmitter and / or the receiver, wherein the steps (e) to (h) include ( e), (f), (g),
It is characterized in that it is performed in the order of (h).

The signal axis aligning method according to claim 9 is the signal axis aligning method according to claim 8, wherein the transmission signal is infrared light, and the receiving device receives the infrared light. Means and a second lens for condensing the infrared light on the light receiving means, and the steps (e) and (g) change the distance between the light receiving means and the second lens. It is characterized by being performed by

According to a tenth aspect of the signal axis aligning method,
The signal axis aligning method according to claim 6 or 7, wherein the step (b) is performed by the signal axis aligning method according to claim 8 or 9.

The signal axis aligning method according to claim 11 is
The signal axis aligning method according to claim 8 or 9, wherein the step (f) is performed by the signal axis aligning method according to claim 6 or 7.

[0026]

BEST MODE FOR CARRYING OUT THE INVENTION <First Embodiment> In the following embodiments, an infrared transmission device using infrared light as a transmission signal will be described as an example of a transmission device for wireless communication.

FIG. 1 is a diagram for explaining a method of aligning an optical axis (signal axis) of an infrared transmission device according to the first embodiment of the present invention. In the figure, 1 is a transmitter for optical communication that converts an electrical signal such as a video signal (video signal) or an audio signal (audio signal) into an optical signal (infrared light) and outputs the optical signal, and 2 is an optical signal received Is a monitor TV for displaying an image output according to an output signal from the receiving device 2. Further, 11 is a directivity adjusting lens for adjusting the directivity of the infrared light output from the light emitting element of the transmitter 1, and 21 is the receiver 2.
Condensing lens for condensing infrared light on the light receiving element of 2
Reference numeral 2 is a light emitting diode (LED) for displaying the level of infrared light detected by the light receiving element of the receiving device 2.

The transmitter 1 of the infrared transmitter according to the present embodiment can change only the directivity without changing the optical axis direction of the infrared light as the transmission signal (the central axis direction of the infrared beam). In FIG. 1, reference numeral 12 indicates infrared light when the directivity is narrowed, and 13 indicates infrared light when the directivity is widened.

FIG. 2 is a block diagram showing an example of the configuration of the transmitter 1. In this figure, 30 is an input video signal processing circuit for converting an input video signal into a signal for optical transmission, 3
1 is a video signal FM modulator that FM-modulates the video signal processed by the input video signal processing circuit 30, and 32 is an audio signal FM that FM-modulates the input audio signal.
The modulator 33 is a mixing circuit for synthesizing the FM-modulated video signal and the audio signal, and 34 is a drive circuit for driving the light emitting element 35 based on the FM modulation signal output from the mixing circuit 33. The light emitting element 35 is driven by the drive circuit 34 and generates infrared light as a transmission signal via the directivity adjusting lens 11.

Here, the operation of the transmitter 1 will be described. A video signal and an audio signal are input to the transmitter 1. The video signal is input to the input video signal processing circuit 30, converted into a signal for optical transmission, and then FM-modulated by the video signal FM modulator. On the other hand, the audio signal is FM-modulated by the audio signal FM modulator 32. F
The M-modulated video signal and audio signal are combined by the mixing circuit 33, converted into an optical signal (infrared light) by the drive circuit 34 and the light emitting element 35, and output via the directivity adjusting lens 11.

Further, FIG. 3 is a diagram for explaining the operation of changing the directivity of infrared light which is a transmission signal in the transmitter 1. In this figure, 11a is a directivity adjusting lens 11 when the infrared light 12 having a narrow directivity is emitted.
11b indicates the position of the directivity adjusting lens 11 when the infrared light 13 having a wide directivity is emitted. That is, in the present embodiment, the transmitting device is the light emitting element 35.
The directivity of the emitted infrared light is changed by changing the distance between the directivity adjusting lens 11 and the directivity adjusting lens 11. As shown in the figure, the optical axis of the directivity adjusting lens 11 and the optical axis of the infrared light are arranged so as to coincide with each other. Then, the directivity adjusting lens 11 is translated in the optical axis direction,
It does not change the optical axis of infrared light, but changes only its directivity.

FIG. 4 is a block diagram showing an example of the configuration of the receiving device 2. In this figure, 40 is a light receiving element for receiving infrared light from the transmitting device 1 via the condenser lens 21, 41 is a light receiving preamplifier for amplifying the infrared light received by the light receiving element 40, and 42 is a received signal. A video band pass filter (BPF) for extracting more video signal components, 43 is a video signal FM demodulator for demodulating the extracted video signal, and 44 is a video signal demodulated by the video signal FM demodulator 43. Is an output video signal processing circuit for converting into a video signal for use in outputting.
Further, 45 is an audio BPF for extracting an audio signal component from the received signal, and 46 is an audio signal FM demodulator that demodulates and outputs the extracted audio signal.

Further, 47 is a level detector for detecting the intensity of infrared light received by the light receiving element 40 based on the output of the light receiving preamplifier 41, and 48 is the light receiving element 40 receiving the light based on the output of the level detector 47. It is a level display circuit that controls the display of the LED 22 according to the intensity of the infrared light being emitted. That is, the user can recognize the intensity of the infrared light received by the receiving device 2 by the display of the LED 22.

Here, the operation of the receiving device 2 will be described. The infrared light including the video signal and the audio signal received by the light receiving element 40 via the condenser lens 21 is amplified by the light receiving unit preamplifier 41. Then, the video signal is separated and extracted by the video BPF 42, and the audio signal is separated and extracted by the audio BPF 45. Video B
The video signal extracted by the PF 42 is the video signal FM.
It is demodulated by the demodulator 43 and output to the monitor TV 3 or the like via the output video signal processing circuit 44. On the other hand, the audio signal extracted by the audio BPF 45 is
The audio signal FM demodulator 46 demodulates and outputs. These video signals and audio signals are input to the monitor 3 for viewing. At this time, the output of the light receiving unit preamplifier 41 is also input to the level detector, and the intensity of the infrared light received by the light receiving element 40 is detected. The level display circuit controls the display of the LED 22 according to the value detected by the level detector 47.

FIG. 5 is a diagram for explaining an example of the display operation of the LED 22 of the receiving device 2 (that is, the control operation of the level display circuit 48). As shown in this figure, when the light receiving intensity of the light receiving element 40 increases and the level of the output signal from the light receiving element 40 exceeds a predetermined allowable level for actual use, LE
D22 lights up. That is, the optical axis alignment in the present embodiment is performed so that the LED 22 of the light receiving device 2 is turned on by the infrared light from the transmitting device 1.

Next, an optical axis alignment method using the transmitter 1 and the receiver 2 in the infrared transmitter according to this embodiment will be described. First, the general directions of the transmitter 1 and the receiver 2 are visually determined. Then, the directivity adjusting lens 11 of the transmitter 1 is set to the position 11b in FIG. 3, and the infrared light emitted from the transmitter 1 is changed to 13 in FIG.
It has a wide directivity as shown in.

FIG. 6 shows the direction in which the receiving device 2 is located and the output level of the light receiving element 40 (that is, the light receiving element 40 when the optical axis direction of the infrared light output from the transmitting device 1 is 0 degree).
FIG. 3 is a diagram showing a relationship with the intensity level of infrared light received by the light source. In this figure, 50 is the distribution when the directivity of the infrared light output from the transmitter 1 is narrow as in 12 of FIG. 1, and 51 is the distribution when the directivity is wide as in 13 of FIG. ing. As shown in this figure, when the directivity is wide, the infrared light is dispersed in a wide range, so the intensity of the infrared light that can be received by the light receiving element 40 in the vicinity of the optical axis direction becomes low, so the transmission efficiency is poor and external noise is generated. Are also easily affected by. Therefore, the transmitter 1 is normally used.
It is necessary to narrow the directivity of the infrared light output by the device as shown by 12 in FIG. However, when the directivity is wide, the angle range in which the light receiving element 40 can receive the infrared light having the intensity equal to or higher than the allowable level is wide.

Then, with the directivity of the infrared light output from the transmitter 1 being widened, the transmitter 1 and the receiver 2
The position and direction of are adjusted so that the LED 22 lights up. At that time, the receiving device 2 is located as close as possible to the center of the area where the LED 22 is turned on. In this adjustment, since the directivity of the infrared light output by the transmitter 1 is wide,
As indicated by 51 in FIG. 6, the angle range in which the amount of infrared light received by the light receiving element 40 is equal to or higher than the allowable level is wide, and
The area where the ED 22 lights up can be easily found.
By this operation, the receiving device 2 is installed near the optical axis direction of the infrared light 13. However, in the state where the directivity of the infrared light is wide as described above, the intensity of the infrared light that can be received is low even if the receiving device 2 is installed near the optical axis direction, and the transmission efficiency is very poor. Hereinafter, for convenience of description, the adjustment of the position and the direction in a state where the directivity of the infrared light output from the transmission device 1 is widened is referred to as “first optical axis adjustment”.

When the first optical axis adjustment is completed, the directivity adjusting lens 1 is continuously moved so that the position of the light emitting element 35 becomes the focal point of the directivity adjusting lens 11 as shown by 11a in FIG.
The position of 1 is adjusted so that the infrared light emitted from the transmitter 1 has a narrow directivity as shown by 12 in FIG. 1 (that is, the directivity is in a normal use state). At this time, if the receiving device 2 is not accurately positioned in the optical axis direction by the above-described first optical axis adjustment, the LED 22 is turned off. Then, the positions and directions of the transmitting device 1 and the receiving device 2 are adjusted again so that the LED 1 lights up. For convenience of explanation, the adjustment of the position and direction in a state where the directivity of the infrared light output from the transmission device 1 is narrowed (normal use state) is referred to as “second optical axis adjustment”.

In the second optical axis adjustment, the optical axis is aligned with infrared light having a narrow directivity. But,
Since the rough alignment of the optical axis has already been completed by the first optical axis adjustment performed before that, and the direction of the optical axis is roughly known, it is easy to find the optimum point even for infrared light with a narrow directivity. Can be obtained.

Then, by confirming the output of the image and the sound based on the infrared light from the transmitter 1 by the monitor TV 3, it is confirmed that the lighting of the LED 22 of the receiver 2 is not due to external optical noise or the like.

By the above operation, the receiving device 2 is accurately installed in the optical axis direction of the infrared light output from the transmitting device 1, and the optical axis alignment is completed. At this time, since the directivity of the infrared light is narrow, the intensity of the infrared light received by the light receiving element 40 is high and the transmission efficiency is high. Therefore, the receiving device 2 is not easily affected by external optical noise. Also,
Since it does not emit unnecessary infrared light to the surroundings, it also has an advantage that it is unlikely to interfere with other devices.

Further, the transmitting apparatus 1 according to this embodiment is
Unlike the conventional transmitter shown in FIG. 11, a single light emitting element 35 is used, and the light emitting element 35 and the directivity adjusting lens 1 are used.
Infrared light with narrow directivity by changing the distance from 1
2 and infrared light 13 having a wide directivity are output. Therefore, the optical axis of the narrow directivity infrared light 12 and the optical axis of the wide directivity infrared light 13 can be accurately aligned by accurately moving the directivity adjusting lens 11 in parallel with the optical axis direction. It is possible.

In the above description, the transmitter 1
The configuration is shown in which the directivity of the infrared light output by is adjusted by moving the position of the directivity adjusting lens 11 with respect to the fixed light emitting element 35. However, the directivity adjusting lens 11 is fixed and light emission is performed. The element 35 may be moved.

Further, although the configuration in which the directivity is changed in two steps is shown here, the present invention is not limited to this, and
It may have a configuration in which the directivity is changed in multiple stages of stages or more, or continuously. That is, the directivity adjusting lens 11
The distance between the light emitting element 35 and the light emitting element 35 may be changed in two or more steps, or continuously.

The first optical axis adjustment and the second optical axis adjustment may be performed to adjust the positions and directions of both the transmitter 1 and the receiver 2, or the transmitter 1 and the receiver. The position and direction of only one of the devices 2 may be adjusted.

Furthermore, in order to make it easy for the user to recognize the set position of the directivity adjusting lens 11, a point marker mechanism for marking a predetermined set position of the directivity adjusting lens 11 and the directivity adjusting lens 11 are provided. A click mechanism or the like may be added to provide a hook at a predetermined position when continuously moving. Thereby, for example, it is possible to easily fix the directivity adjusting lens 11 at a position where the directivity of infrared light is narrowed down most and the efficiency is maximized during the second optical axis adjustment. .

<Embodiment 2> As described above, in the conventional receiver of the infrared transmission device, in order to make it easy to align the optical axis, the infrared light can be received from a wide angle. The range of the incident angle (light receiving angle) that can be received by the element is widened, so that the receiving efficiency of the incident light is lowered. Further, there is also a problem that extraneous optical noise light or the like is likely to enter the light receiving element and is easily affected by the light.

FIG. 7 is a diagram for explaining the optical axis alignment method of the infrared transmission device according to the second embodiment of the present invention.
In this figure, elements having the same functions as those in FIG. 1 are designated by the same reference numerals, and detailed description thereof will be omitted here. The configurations of the transmitting device 1 and the receiving device 2 are similar to those shown in FIGS. 2 and 4, respectively.

In the present embodiment, the transmitting device can change only the size of the light receiving angle without changing the direction of the central axis of the light receiving angle of the light receiving element.
0 indicates the range of the light-receivable direction when the light-receiving angle is narrowed, and 61 indicates the range of the light-receivable direction when the light-receiving angle is widened. In the present embodiment, in order to improve the receiving efficiency of the receiving device, a state of a narrow light receiving angle such as 60 is set to a normal use state for performing communication.

Further, FIG. 8 is a diagram for explaining the operation of changing the light receiving angle of the light receiving element 40 in the receiving device 2. In this figure, 21a is the position of the condenser lens 21 for producing a narrow light receiving angle 60, and 21b is a wide light receiving angle 6
The position of the condenser lens 21 when producing 1 is shown. That is, in the present embodiment, the transmitting device changes the light receiving angle of the light receiving element 40 by changing the distance between the light receiving element 40 and the condenser lens 21. As shown in the figure, the optical axis of the condenser lens 21 and the optical axis of the infrared light are arranged so as to coincide with each other. Then, by moving the condenser lens 21 in parallel with the optical axis direction, only the magnitude of the light receiving angle is changed without changing the central axis of the light receiving angle.

Next, an optical axis alignment method using the transmitter 1 and the receiver 2 in the infrared transmitter according to the present embodiment will be described. First, the light receiving lens 21 of the receiving device 2 is set to the position 21b in FIG. 8 so that the light receiving element 40 of the receiving device 2 has a wide light receiving angle as indicated by 61 in FIG.

Next, in the same procedure as in the first embodiment, the first
The optical axis adjustment and the second optical axis adjustment are performed. As a result, the light receiving lens 21 of the receiving device is located in the optical axis direction of the infrared light having a narrow directivity output from the transmitting device 1. At this time, since the light receiving angle of the receiving device 2 is wide, the first optical axis adjustment and the second optical axis adjustment can be easily performed, but the light receiving efficiency is poor.

Subsequently, as shown by 21a in FIG. 8, the position of the directivity adjusting lens 21 is adjusted so that the position of the light receiving element 40 becomes the focal point of the light receiving lens 21, and the light receiving angle of the receiving device 2 is shown in FIG. As shown in No. 60, narrow the width. At this time, if the central axis direction of the light receiving angle of the transmitter 2 and the optical axis direction of the transmitter 1 do not match by the first optical axis adjustment and the second optical axis adjustment, the LED 22 is turned off. In that case, the positions and directions of the transmitter 1 and the receiver 2 are adjusted so that the LED 22 is turned on again. For convenience of explanation, the adjustment of the position and direction of the transmission device 1 and the reception device 2 when the light receiving angle of the reception device 2 is narrowed is referred to as “third optical axis adjustment”.

In the third optical axis adjustment, the optical axis is aligned with the receiving device 2 having a narrow light receiving angle. However, since the first optical axis adjustment and the second optical axis adjustment performed before that, the light receiving lens 21 of the receiving device 2 is already located in the optical axis direction of the infrared light output from the transmitting device 1, Even in the receiving device 2 having a narrow light receiving angle, the optimum point can be easily obtained.

Then, the monitor TV 3 confirms the output of the image and the sound based on the infrared light from the transmitting device 1, and confirms that the lighting of the LED 22 of the receiving device 2 is not due to external optical noise or the like.

By the above operation, the transmitter 1 is accurately installed at the center of the narrow light receiving angle of the receiver 2.
The optical axis alignment is completed. As a result, since the light receiving angle of the receiving device 2 is narrow, the light receiving element 40 can efficiently receive the infrared light. Therefore, it is less susceptible to external optical noise.

In this embodiment, the alignment between the transmitter 1 and the receiver 2 performed before the third optical axis adjustment is performed by the first optical axis adjustment and the first optical axis adjustment shown in the first embodiment. A method of performing the second optical axis adjustment has been shown. However, the application of the present invention is not limited to this method, and the transmitter 1 that is performed before the third optical axis adjustment by any method other than the first optical axis adjustment and the second optical axis adjustment. May be aligned with the receiving device 2. Even in that case, the third
It is obvious that the effect of improving the light receiving efficiency of the receiving device 2 and improving the optical noise resistance can be obtained by narrowing the light receiving angle of the receiving device 2 when adjusting the optical axis of.

In the above description, the receiving device 2
Although the light receiving angle is adjusted by moving the position of the light receiving lens 21 with respect to the fixed light receiving element 40, the light receiving lens 21 may be fixed and the light receiving element 40 may be moved. .

Further, although the configuration in which the light receiving angle is changed in two steps is shown here, the present invention is not limited to this, and
It may have a configuration in which the light receiving angle is changed in multiple steps or more, or continuously. That is, the distance between the light receiving lens 21 and the light receiving element 40 may be changed in two or more steps, or continuously.

The third optical axis adjustment may be performed by adjusting the position and direction of both the transmitter 1 and the receiver 2, or either one of the transmitter 1 and the receiver 2 may be adjusted. The position and direction of the chisel may be adjusted.

Further, in order to make it easy for the user to recognize the setting position of the light receiving lens 21, a point marker mechanism for marking a predetermined setting position of the light receiving lens 21 or a predetermined position when the light receiving lens 21 is continuously moved. A click mechanism or the like for providing a catch may be added. Thereby,
For example, when the third optical axis is adjusted, it is possible to easily fix the light receiving lens 21 at a position where the light receiving angle is narrowed down most and efficiency is maximized.

<Third Embodiment> In the first and second embodiments, the LED 22 of the receiving device 2 is turned on when the light-receiving intensity of the light-receiving element 40 exceeds a predetermined allowable level. In other words, the user can only judge whether the received light intensity is above the allowable level or below the allowable level based on the display. In the present embodiment, a configuration is shown in which the user can determine a more specific strength of received light intensity.

In the present embodiment, in the receiving device 2 shown in FIG. 4, according to the output of the level detector 47,
The level display circuit 48 changes the display by the display device LED 22 in multiple steps.

FIG. 9 is a diagram for explaining the display operation of the LED 22 (that is, the control operation of the level display circuit 48) of the receiving device 2 according to the present embodiment. As shown in this figure, the light receiving intensity of the light receiving element 40 increases and the light receiving element 40
First, when the level of the output signal from exceeds the predetermined blinking start level, the level display circuit 48 blinks the LED 48. At this time, the blinking cycle of the LED 48 is determined by the light receiving intensity of the light receiving element 40, and the light receiving intensity is increased and the output level of the light receiving element 40 is controlled so as to be shorter. Then, when the light receiving intensity of the light receiving element 40 further increases and the level of the output signal from the light receiving element 40 exceeds a predetermined allowable level for use, the LED 22 is constantly turned on. That is, the user can recognize the intensity of the infrared light received by the light receiving element 40 based on the blinking speed of the LED 48.

FIG. 10 shows the direction in which the receiving device 2 is located and the output level of the light receiving element 40 (that is, the light receiving element 4 when the optical axis direction of the infrared light output from the transmitting device 1 is 0 degrees).
It is a figure which shows the relationship with the intensity | strength of the infrared light which 0 receives). Similar to FIG. 6, 50 is a distribution when the directivity of the infrared light output from the transmission device 1 is narrow as shown by 12 in FIG. 1, and 51 is a distribution when the directivity is wide as shown by 13 in FIG. Is shown. As shown in this figure, the intensity of the infrared light received by the light receiving element 40 in the vicinity of the optical axis direction is higher than in other directions regardless of whether the directivity of the infrared light is wide or narrow.

Therefore, in the first and second embodiments,
When performing the first optical axis adjustment, the second optical axis adjustment, and the third optical axis adjustment, if the receiving device 1 and the transmitting device 2 are moved in a direction in which the LED 22 of the receiving device 2 blinks quickly. ,
Since the light receiving lens of the receiving device 2 can be located more in the center of the infrared light, the optical axis can be aligned more efficiently.

Further, the LED 22 may always display the received light intensity not only when the optical axis is aligned but also when actually used. In that case, it is possible to detect the deterioration of the transmission quality due to a deviation in the direction of the transmitter or the receiver during actual use. That is, it is possible to easily confirm and manage the transmission quality during actual use. Furthermore, in that case, with the configuration shown in the third embodiment, the change from lighting to blinking of the display device LED 22 can be regarded as an alarm when the optical axis is slightly deviated from the optimum value, and the deterioration of communication quality. It can also be used to prevent this.

In the above description, the receiving device 2
An LED is used as a means for displaying the received light intensity, and the received light intensity is displayed by lighting or blinking light.
However, the display means of the received light intensity is not limited to this, and as the display means, for example, a display device indicating the received light intensity by letters, numbers, graphs, etc., or a voice generation device for notifying the received light intensity by sound or voice is used. Even with the configuration, it is obvious that the same effect can be obtained.

Further, in the above embodiments, the infrared transmission device using infrared light as a transmission signal has been described. However, the application of the present invention is not limited to this, and it is widely applicable to, for example, a wireless communication transmission device that uses an invisible transmission signal such as an electric wave or an ultrasonic wave as a transmission signal. For example, in the case of a wireless communication transmission device using radio waves, as directivity adjusting means for adjusting its directivity,
It can be implemented by using an electromagnetic coil or the like.

[0071]

According to the transmitting device of the first aspect, the transmitting device emits the transmitting signal for wireless communication, and the transmitting signal generating means for generating the transmitting signal and the directivity of the transmitting signal are changed. Since it is provided with a directivity adjusting means for making, the signal axis is roughly adjusted in a state where the directivity of the transmission signal is widened,
The signal axis can be easily adjusted by making a fine adjustment after narrowing the directivity. Further, at this time, the signal axis can be accurately aligned by not changing the signal axis direction.

That is, even if the directivity of the transmission signal in the normal use state is narrowed, the signal axes can be easily and accurately adjusted, and the transmission efficiency and the noise resistance can be improved. In that case, there is also an advantage that unnecessary transmission signals are not emitted to the surroundings, so that it is difficult to give interference to other devices.

According to a second aspect of the present invention, there is provided the transmitter according to the first aspect, wherein the transmission signal is infrared light and the directivity adjusting means is the first lens through which the infrared light passes. Since the directivity of infrared light is changed by changing the distance between the transmission signal generating means and the first lens, it is possible to change the directivity of infrared light using a single transmission signal generating means. You can Therefore, by accurately moving the first lens or the transmission signal generating means in parallel with the optical axis direction of the infrared light, it is possible to change only the directivity of the infrared light without surely changing the signal axis direction. it can.

According to a third aspect of the present invention, there is provided a receiving device for receiving a transmission signal for wireless communication, wherein the receiving means for receiving the transmission signal and the size of the receiving angle of the receiving means are changed. Since the receiving angle adjusting means is provided, the signal axis can be easily adjusted by roughly adjusting the signal axis with the receiving angle of the receiving means widened and then performing the fine adjustment after narrowing the receiving angle. Further, since the signal axis direction does not change at this time, the signal axis can be accurately aligned.

That is, even if the receiving angle of the receiving means in the normal use state is narrowed, the signal axis can be easily and accurately adjusted, and the receiving efficiency and the optical noise resistance can be improved.

According to a fourth aspect of the present invention, in the third aspect of the present invention, the transmission signal is infrared light, and the reception angle adjusting means focuses the infrared light on the receiving means. Since the size of the reception angle is changed by changing the distance between the reception means and the second lens, the size of the reception angle is changed by using a single reception means. Can be made. Therefore, by accurately moving the second lens or the receiving means in parallel with the central axis direction of the receiving angle, it is possible to change only the receiving angle of the receiving means without reliably changing the central axis direction of the receiving angle. Can be changed.

According to a fifth aspect of the present invention, there is provided the receiving apparatus according to the third or fourth aspect, wherein the level detecting means detects the intensity level of the transmission signal received by the receiving means. Since the level display means for performing a display corresponding to the intensity level detected by the detection means is provided, the user can recognize the reception intensity level of the reception means at the time of signal axis alignment. The user can easily adjust the signal axes by adjusting the positions and directions of the transmitting device and the receiving device based on the display. It can also be used for confirmation and management of transmission quality during actual use.

According to the signal axis aligning method of the sixth aspect of the present invention, there is provided a signal axis aligning method between a transmitter and a receiver for wireless communication, wherein (a) directivity of a transmission signal transmitted by the transmitter is A step of making it wider than the normal use state; (b) a step of performing a first adjustment for changing the position and direction of the transmitting device and / or the receiving device; and (c) a directivity of a transmission signal received by the transmitting device. , The step of putting into normal use,
(D) a step of performing a second adjustment for changing the position and direction of the transmitting device and / or the receiving device, wherein steps (a) to (d) include (a), (b), (c), (D)
Therefore, in the step (b), the receiving device can receive a transmission signal having a directivity wider than that in the normal use state at a predetermined intensity level or more, and roughly aligns the signal axis to perform normal use. Even when the directivity of the transmission signal in the state is narrow, the second adjustment in the step (d) can be easily performed. Further, by not changing the signal axis direction in the steps (b) and (d),
The signal axis can be accurately aligned.

That is, even if the directivity of the transmission signal in the normal use state is narrowed, the signal axes can be easily and accurately adjusted, and the transmission efficiency and the noise resistance can be improved. In that case, there is also an advantage that unnecessary transmission signals are not emitted to the surroundings, so that it is difficult to give interference to other devices.

According to the signal axis aligning method described in claim 7, the signal axis aligning method according to claim 6, wherein the transmission signal is infrared light, and the transmitting device generates infrared light. It has a generation means and a first lens through which infrared light passes, and since steps (a) and (c) are performed by changing the distance between the infrared light generation means and the first lens, The directivity of infrared light can be changed by using one infrared light generating means. Therefore, the first
By accurately moving the lens or the infrared light generation means in parallel with the optical axis direction of the infrared light, it is possible to change only the directivity of the infrared light without reliably changing the signal axis direction.

According to the signal axis aligning method of the eighth aspect of the present invention, there is provided a signal axis aligning method between a transmitter and a receiver for wireless communication, wherein (e) the reception angle size of the receiver is normally used. The step of making it wider than the state, (f) the step of performing a third adjustment for changing the position and direction of the transmitting device and / or the receiving device, and (g) the size of the receiving angle of the receiving device in the normal use state And (h) performing a fourth adjustment for changing the position and direction of the transmitting device and / or the receiving device, wherein steps (e) to (h) include
Since (e), (f), (g), and (h) are performed in this order,
In step (f), the receiving device can receive a transmission signal having a directivity wider than that in the normal use state so as to receive a transmission signal having a predetermined intensity level or more, and roughly adjusts the signal axis to thereby obtain a reception angle of the receiving means in the normal use state. Even when is narrow, the fourth adjustment in the step (h) can be easily performed. Further, the signal axis alignment can be accurately performed by not changing the signal axis direction in the steps (f) and (h).

That is, even if the receiving angle of the receiving means in the normal use state is narrowed, the signal axes can be easily and accurately adjusted, and the receiving efficiency and the optical noise resistance can be improved.

According to a ninth aspect of the signal axis aligning method, the signal axis aligning method according to the eighth aspect is characterized in that the transmission signal is infrared light and the receiving device receives the infrared light. And a second lens for condensing infrared light on the light receiving means, and steps (e) and (g) are performed by changing the distance between the light receiving means and the second lens. The size of the reception angle can be changed by using a single light receiving means. Therefore, by accurately moving the second lens or the light-receiving means in parallel with the direction of the central axis of the receiving angle, the size of the receiving angle of the receiving means is not changed without changing the central axis direction of the receiving angle. Can be changed.

According to the signal axis aligning method described in claim 10, the signal axis aligning method according to claim 6 or 7, wherein the step (b) is performed according to claim 8 or 9. Since it is performed by the signal axis alignment method of (1), the step (b) can be easily performed even when the reception angle of the receiving device in a normal use state is narrow.

According to the signal axis aligning method described in claim 11, the signal axis aligning method according to claim 8 or 9, wherein the step (f) is performed according to claim 6 or 7. Since the signal axis alignment method is used, the step (f) can be easily performed even when the directivity of the transmission signal in the normal use state is narrow.

[Brief description of drawings]

FIG. 1 is a diagram for explaining an optical axis alignment method of an infrared transmission device according to a first embodiment.

FIG. 2 is a block diagram showing an example of a configuration of a transmitting apparatus according to the first embodiment.

FIG. 3 is a diagram for explaining an operation of changing the directivity of infrared light, which is a transmission signal, in the transmission device according to the first embodiment.

FIG. 4 is a block diagram showing an example of a configuration of a receiving apparatus according to the first embodiment.

FIG. 5 is a diagram for explaining an example of an LED display operation of the receiving device according to the first embodiment.

FIG. 6 is a diagram showing the relationship between the direction in which the receiving device is located with respect to the transmitting device and the output level of the light receiving element in the infrared transmission device according to the first embodiment.

FIG. 7 is a diagram for explaining a method of aligning the optical axis of the infrared transmission device according to the second embodiment.

FIG. 8 is a diagram for explaining the operation of changing the light receiving angle of the light receiving element in the receiving device according to the second embodiment.

FIG. 9 is a diagram for explaining an LED display operation of the receiving device according to the third embodiment.

FIG. 10 is a diagram showing the relationship between the direction in which the receiving device is located with respect to the transmitting device and the output level of the light receiving element in the infrared transmission device according to the third embodiment.

FIG. 11 is a diagram for explaining the principle of an optical axis alignment method in a conventional transceiver for optical wireless communication.

[Explanation of symbols]

1 transmitter, 2 receiver, 3 monitor TV, 11
Directivity adjustment lens, 21 condenser lens, 22 LE
D, 12 infrared light with narrow directivity, 13 infrared light with wide directivity, 30 input video signal processing circuit, 31 video signal FM modulator, 32 audio signal FM modulator,
33 mixed circuit, 34 drive circuit, 35 light emitting element, 40 light receiving element, 41 light receiving section preamplifier, 42
Video BPF, 43 Video signal FM demodulator, 44 Output video signal processing circuit, 45 Audio BPF, 46
Audio signal FM demodulator, 47 level detector, 4
8 level display circuit, 60 narrow light receiving angle, 61 wide light receiving angle.

Claims (11)

[Claims] 1. A transmission device for transmitting a transmission signal for wireless communication, comprising: a transmission signal generating means for generating the transmission signal; and a directivity adjusting means for changing a directivity of the transmission signal. And a transmitter. 2. The transmission device according to claim 1, wherein the transmission signal is infrared light, and the directivity adjusting unit has a first lens through which the infrared light passes, A transmitting device, characterized in that the directivity of the infrared light is changed by changing the distance between the signal generating means and the first lens. 3. A receiving device for receiving a transmission signal for wireless communication, comprising: receiving means for receiving the transmission signal; and reception angle adjusting means for changing the size of the reception angle of the receiving means. A receiving device characterized by the above. 4. The receiving device according to claim 3, wherein the transmission signal is infrared light, and the reception angle adjusting means collects the infrared light in the receiving means. A receiving device comprising a lens, wherein the size of the reception angle is changed by changing the distance between the receiving means and the second lens. 5. The receiving device according to claim 3, wherein the level detecting unit detects an intensity level of the transmission signal received by the receiving unit, and the level detecting unit detects the level. And a level display unit for displaying a display corresponding to the intensity level. 6. A method for aligning a signal axis between a transmitter and a receiver for wireless communication, comprising: (a) making the directivity of a transmission signal transmitted by the transmitter wider than in a normal use state; b) a step of performing a first adjustment for changing the position and direction of the transmitting device and / or the receiving device, and (c) directivity of the transmission signal received by the transmitting device is set to the normal use state. And (d) performing a second adjustment for changing the position and direction of the transmitting device and / or the receiving device, wherein the steps (a) to (d) include (a) and (b). ),
(C) and (d) are performed in this order, a signal axis alignment method characterized by the above-mentioned. 7. The signal axis aligning method according to claim 6, wherein the transmission signal is infrared light, and the transmitting device generates infrared light, and the infrared light generating means generates the infrared light. A first lens passing therethrough, wherein the step (a) and the step (c) are performed by changing a distance between the infrared light generation means and the first lens. Signal axis alignment method. 8. A method for aligning a signal axis between a transmitter and a receiver for wireless communication, comprising: (e) a step of making the size of a reception angle of the receiver larger than that in a normal use state; and (f) Performing a third adjustment for changing the position and direction of the transmitter and / or the receiver, (g) setting the size of the reception angle of the receiver to the normal use state, and (h) ) Performing a fourth adjustment for changing the position and orientation of the transmitting device and / or the receiving device, wherein the steps (e) to (h) include (e), (f),
(G) and (h) are performed in this order, a signal axis aligning method characterized by the above-mentioned. 9. The signal axis aligning method according to claim 8, wherein the transmission signal is infrared light, and the receiving device receives the infrared light.
The light receiving unit has a second lens for condensing the infrared light, and the steps (e) and (g) are performed by changing the distance between the light receiving unit and the second lens. Will be
A signal axis aligning method characterized by the above. 10. The signal axis aligning method according to claim 6 or 7, wherein the step (b) is performed by the signal axis aligning method according to claim 8 or 9. Characteristic signal axis alignment method. 11. The signal axis aligning method according to claim 8 or 9, wherein the step (f) is performed by the signal axis aligning method according to claim 6 or 7. Characteristic signal axis alignment method.