JP3800195B2 - Optical wireless transmission device, optical axis adjustment method of optical wireless transmission device, optical wireless communication method, and optical wireless transmission system - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an optical wireless transmission apparatus that transmits and receives light modulated by a data signal or the like, an optical axis adjustment method of the optical wireless transmission apparatus, an optical wireless communication method, and an optical wireless transmission system.
[0002]
[Prior art]
In general, when transmitting a signal via optical radio, an LED (light emitting diode) or a laser diode is used as a light emitting element on the transmission side. Of these, in devices that transmit signals using LEDs, the beam diameter of LED light with a wide directivity must be narrowed by a focusing lens. However, because this diaphragm has a limit, the beam diameter widens when it is transmitted over long distances. Power is reduced. When the beam diameter is increased in this way, there is a problem that interference occurs when a plurality of devices are used in parallel.
[0003]
In order to solve this, for example, an indoor optical wireless transmission device as shown in FIG. 23 has been proposed. In this optical wireless transmission device, a light emitting means 23 is provided in one device (master unit 21) separately from the light emitting unit 22 for data signal transmission, and pilot light 23A for adjusting the optical axis is transmitted from the light emitting means 23. In the other optical wireless transmission device (slave unit 24), the optical axis direction is displaced, the pilot light 23A is received by the light receiving device 24A, and the optical axis is aligned based on the received light level of the pilot light 23A. It is configured. This device collimates the LED light with a parabolic reflector so as to reduce the beam diameter. By rotating the light receiving device 24A that receives beam light with a narrow directivity by a stepping motor or the like, the horizontal and vertical directions are obtained. This is embodied in the form of scanning and searching for a point where the maximum light receiving level is obtained in two-dimensional coordinates (see, for example, Patent Document 1).
[0004]
On the other hand, in an outdoor optical wireless transmission device using a laser diode, an optical axis adjustment method using a mirror and a beam splitter is employed (for example, see Patent Document 2).
[0005]
[Patent Document 1]
Patent No. 3059870
[0006]
[Patent Document 2]
JP-A-6-152541
[0007]
[Problems to be solved by the invention]
In order to perform optical axis adjustment with the indoor optical wireless transmission device, it is necessary to rotate the light receiving device including the light receiving element and its optical system and the light emitting device including the light emitting element and the optical system at the same time. The device becomes large to be used in.
[0008]
Further, in order to perform higher-speed transmission, it is necessary for the receiving side to receive the transmission light from the partner apparatus with high efficiency, and the transmission light has a very narrow directivity angle of about several degrees [deg]. Must be a beam. When performing two-way communication, it is necessary to match the optical axes of the light emitting device and the light receiving device arranged in the same device, but when the directivity of the transmitted light is very narrow, it is up and down like this device. It was difficult to align the optical axes of the arranged light emitting device and light receiving device with high accuracy and high speed.
[0009]
Furthermore, as an optical axis adjustment method for matching the optical axes of transmission and reception, the adjustment method of the outdoor optical wireless transmission device can be considered, but this device is a large-scale device using a large number of optical elements. Therefore, the device becomes large and is used for fine adjustment after adjusting the optical axis to some extent, so the searchable range of the partner device is as narrow as several degrees, and it can be moved to various indoor locations. Therefore, it is not suitable for the device used.
[0010]
SUMMARY OF THE INVENTION An object of the present invention is to reduce the size of an apparatus and to perform optical axis alignment with high accuracy and at high speed, and is suitable for indoor use, and an optical axis adjustment method for an optical wireless transmission apparatus An optical wireless communication method and an optical wireless transmission system are provided.
[0011]
[Means for Solving the Problems]
In order to achieve the above object, the invention of claim 1 is a light emitting element that emits light modulated by a data signal or pilot light for optical axis adjustment, and light emitted from the light emitting element is a beam light that is close to parallel light. A first optical element to be molded, a first and second light control element that reflects part of the incident light and transmits the remainder, and reflects the incident light and controls the deflection angle of the incident light with respect to the optical axis Reflective optical system having a driving means, a second optical element for condensing light transmitted from the counterpart device, a first light receiving element for receiving light collected by the second optical element, and transmitted from the counterpart device A third optical element for condensing light; a second light receiving element for receiving the light collected by the third optical element; and an irradiation area with respect to an optical axis direction of light passing through the first light control element. , With respect to the optical axis direction of the light incident on the second light control element The first and second light control elements are configured to be larger than an irradiation area, and light emitted from the light emitting element is shaped into beam light close to parallel light by the first optical element, and the second After being reflected by the light control element, the light passes through the first light control element, is reflected in a predetermined direction by the reflection optical system, is transmitted as transmission light, and light incident from the counterpart device is reflected by the reflection optical system. A part of the light is reflected by the first light control element, then received by the first light receiving element through the second optical element, and the remaining light is transmitted through the first light control element, A light receiving / emitting section configured to transmit through the second light control element and pass through the periphery of the second light control element, and to be received by the second light receiving element through the third optical element; Based on the pilot light received by the light receiving element, the reflection optical system is deflected. A deflection angle control signal supply unit that calculates a deflection angle control signal for controlling the angle and controls the driving means of the reflection optical system based on the deflection angle control signal, and the second light receiving element includes the counterpart By receiving light from the device as a data signal and controlling the deflection angle of the reflective optical system based on the pilot light received by the first light receiving element, the light emitted from the light emitting element and the counterpart device An optical wireless transmission device that performs optical axis alignment of incident light.
[0012]
According to a second aspect of the present invention, in the optical wireless transmission device according to the first aspect, the light emitting / receiving unit forms the light emitted from the light emitting element into beam light close to parallel light by the first optical element. Then, after being reflected by the second light control element, transmitted through the first light control element, reflected by the reflective optical system in a predetermined direction, transmitted to the counterpart device, and light incident from the counterpart device is the Reflected by the reflecting optical system, a part of the light is reflected by the first light control element, then passes through the third optical element and is received by the second light receiving element, and the remaining light is received by the first light control element. Is transmitted through the second light control element, passes through the periphery of the second light control element, passes through the second optical element, and is received by the first light receiving element. It is characterized by.
[0013]
According to a third aspect of the present invention, there is provided a light emitting element for emitting light modulated by a data signal or pilot light for adjusting an optical axis, and a first optical element for shaping the light emitted from the light emitting element into beam light close to parallel light. Reflective optical system having first and second light control elements that reflect part of incident light and transmit the rest, and drive means for reflecting incident light and controlling the deflection angle of the incident light with respect to the optical axis A second optical element for condensing the light transmitted from the counterpart device, a first light receiving element for receiving the light collected by the second optical element, and a third for condensing the light transmitted from the counterpart device An optical element, a second light receiving element that receives the light collected by the third optical element, and an irradiation area with respect to an optical axis direction of light passing through the first light control element is the second light control element Smaller than the irradiation area with respect to the optical axis direction of the light incident on As described above, the first and second light control elements are configured, and the light emitted from the light emitting element is shaped into beam light close to parallel light by the first optical element and reflected by the first light control element. Then, the light reflected by the reflective optical system in a predetermined direction is transmitted to the counterpart device, and the light incident from the counterpart device is reflected by the reflective optical system, transmitted through the first light control element, and the first light control. After passing through the periphery of the element, a part of the light is reflected by the second light control element and then received by the first light receiving element through the second optical element, and the remaining light is received by the first and second light elements. A light receiving / emitting unit configured to pass through a light control element and be received by the second light receiving element through the third optical element, and the reflection optics based on pilot light received by the first light receiving element Calculate the deflection angle control signal to control the deflection angle of the system, A deflection angle control signal supply unit for controlling the driving means of the reflection optical system based on the deflection angle control signal, and the second light receiving element receives light from the counterpart device as a data signal, and The optical axis alignment of the light emitted from the light emitting element and the light incident from the counterpart device is performed by controlling a deflection angle of the reflection optical system based on the pilot light received by the light receiving element. An optical wireless transmission device.
[0014]
According to a fourth aspect of the present invention, in the optical wireless transmission apparatus according to the third aspect, the light emitting / receiving unit is configured such that the light emitted from the light emitting element is shaped into a beam light close to parallel light by the first optical element. Then, after being reflected by the first light control element, reflected by the reflective optical system in a predetermined direction and transmitted to the counterpart device, light incident from the counterpart device is reflected by the reflective optical system, After passing through the light control element and passing around the first light control element, a part of the light is reflected by the second light control element and then received by the second light receiving element through the third optical element. The remaining light passes through the second light control element and is received by the first light receiving element through the second optical element.
[0015]
According to a fifth aspect of the present invention, in the optical wireless transmission device according to any one of the first to fourth aspects, the first light receiving element is constituted by a multi-divided light receiving element, and the deflection angle control signal supply The unit is configured to calculate a moving direction and a moving amount of the reflective optical system based on a light receiving amount in each divided region of the light receiving element, and based on the moving direction and the moving amount calculated by the calculating unit. Control means for driving the reflecting optical system driving means in the horizontal direction or the vertical direction to align the optical axes of the light emitted from the light emitting element and the light incident from the counterpart device.
[0016]
According to a sixth aspect of the present invention, in the optical wireless transmission device according to any one of the first to fifth aspects, the constituent members of the light emitting / receiving section are integrally arranged on the same substrate.
[0017]
A seventh aspect of the invention is the optical axis adjustment method for an optical wireless transmission device according to the fifth aspect, wherein light incident from the counterpart device is received by the first light receiving element to constitute the first light receiving element. The movement direction and the movement amount of the reflection optical system are calculated based on the amount of light received by each light receiving element, and the driving means of the reflection optical system is driven in the horizontal direction or the vertical direction based on the movement direction and the movement amount. Thus, the optical axes of the light emitted from the light emitting element and the light incident from the counterpart device are aligned.
[0018]
According to an eighth aspect of the present invention, the optical wireless transmission device according to any one of the first to sixth aspects is disposed as a first optical wireless transmission device and a second optical wireless transmission device facing each other at a predetermined interval. An optical wireless communication method comprising performing two-way communication between the first and second optical wireless transmission devices after optical axis alignment is performed by the optical axis adjustment method of the optical wireless transmission device described .
[0019]
A ninth aspect of the invention is an optical wireless transmission system in which the optical wireless transmission device according to any one of the first to sixth aspects is disposed as a first optical wireless transmission device and a second optical wireless transmission device so as to face each other at a predetermined interval. The optical axis alignment of the first and second optical wireless transmission apparatuses is performed by the optical axis adjustment method of the optical wireless transmission apparatus according to claim 7, and then between the first and second optical wireless transmission apparatuses. And bi-directional communication.
[0024]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of an optical wireless transmission device, an optical axis adjustment method of the optical wireless transmission device, an optical wireless communication method, and an optical wireless transmission system according to the present invention will be described below.
[0025]
In the following description, light modulated by a data signal or pilot light for optical axis adjustment is appropriately referred to as light. Among these, the light modulated by the data signal is appropriately described as the light of the data signal. Further, light transmitted to the counterpart device is referred to as transmission light, outgoing light, or outgoing light, and light received from the counterpart device is referred to as reception light, incident light, or incident light. Furthermore, emitting light is referred to as transmission, and receiving is referred to as light reception or reception.
[0026]
[Embodiment 1]
First, the configuration of the optical wireless transmission apparatus according to the first embodiment will be described with reference to FIG.
[0027]
FIG. 1 is a schematic configuration diagram of an optical wireless transmission apparatus according to the first embodiment.
[0028]
The light receiving / emitting unit 9 includes a light emitting element 1 that emits light modulated by a data signal or pilot light, a lens 2 such as a collimator lens, and a first light control element that reflects part of incident light and transmits the rest. 3A and the second light control element 3B, the reflection optical system 4 having a driving means (not shown) that reflects incident light and controls the deflection angle of the incident light with respect to the optical axis, and pilot light transmitted from a counterpart apparatus (not shown) , A first light receiving element 6 such as a photodiode (hereinafter referred to as PD as appropriate) that receives light collected by the lens 5, and light of a data signal transmitted from the counterpart device And a second light receiving element 36 such as a photodiode for receiving the light collected by the lens 37.
[0029]
The light emitting element 1 and the lens 2 constitute a light emitting unit 41, and the emitted light emitted from the light emitting element 1 through the lens 2 is transmitted through the first light control element 3A and the second light control element 3B (partly reflected, The same applies hereinafter), and is arranged so as to be reflected by the reflection optical system 4 and transmitted as transmission light. The lens 5 and the first light receiving element 6 constitute a first light receiving unit 40, and the pilot light incident from the counterpart device is reflected by the reflection optical system 4 and reflected by the first light control element 3A (partially transmitted, After that, the first light receiving element 6 receives the light through the lens 5. Further, the lens 37 and the second light receiving element 36 constitute a second light receiving unit 39, and the light incident from the counterpart device is reflected by the reflection optical system 4, passes through the first light control element 3A, and the second light control element. After being reflected by 3B (partially transmitted, the same applies hereinafter), the light is received as a data signal by the second light receiving element 36 through the lens 37.
[0030]
In the above configuration, the light emitting unit 41 is connected to the data supply unit 7 and the external interface 7A. The first light receiving unit 40 is connected to the deflection angle control signal supply unit 8, and the second light receiving unit 39 is connected to the reception signal processing unit 38 and the external interface 38A.
[0031]
In the light emitting / receiving unit 9, light whose intensity is modulated in accordance with the data signal is emitted from the light emitting element 1 by the data supply unit 7 to which the data signal is supplied from the external interface 7 </ b> A. This light is shaped into beam light close to parallel light by the lens 2, passes through the second light control element 3 </ b> B and the first light control element 3 </ b> A, is reflected by the reflection optical system 4, and is transmitted as transmission light.
[0032]
In addition, pilot light transmitted from a partner apparatus (not shown) having the same configuration is reflected by the reflection optical system 4 and reflected by the first light control element 3A, and then condensed by the lens 5 and then by the first light receiving element 6. Received light. In the first light receiving element 6, the received light is photoelectrically converted and output to the deflection angle control signal supply unit 8 as a position information signal of the counterpart device.
[0033]
Furthermore, the light of the data signal transmitted from the other device (not shown) having the same configuration is reflected by the reflection optical system 4 and transmitted through the first light control element 3A, and then reflected by the second light control element 3B, and then the lens. The light is condensed by 37 and received by the second light receiving element 36. In the second light receiving element 36, the received transmission light is photoelectrically converted and supplied to the reception signal processing unit 38 as a data signal.
[0034]
Next, with reference to FIGS. 2 to 7, each part constituting the light emitting / receiving unit 9 will be described in more detail.
[0035]
As the light emitting element 1, a laser diode can be used. The laser diode has a narrow beam of emitted light, which is further converted into a nearly parallel beam by the lens 2 so that the emitted light can be efficiently converted into the first light control element 3A, the second light control element 3B, and the reflection optical system 4. Can be irradiated. The wavelength of the laser is not limited to the near infrared, but may be a long wavelength.
[0036]
FIG. 2 is a block diagram showing the configuration of the data supply unit 7. The data supply unit 7 converts the data signal from the external interface 7A into a signal that can be transmitted by light, and light emission that drives the light emitting element 1 so that the light blinks by the signal processed signal. It comprises a drive unit 10.
[0037]
When the indoor optical wireless transmission system is constructed by arranging this apparatus facing each other at a predetermined interval, the LAN is considered as the application, and the signal input from the external interface 7A is 100Base-FX, the signal processing in the data supply unit 7 In the unit 11, as shown in the block diagram of FIG. 4, the 4B / 5B encoder 101 performs 4B / 5B encoding for clock self-regeneration, the descramble / scramble unit 102 scrambles the data, and performs parallel / serial conversion. The signal processing that the parallel data is converted into serial data by the unit 103 and the NRZ / NRZI conversion unit 104 (and the PLL 105) performs NRZ / NRZI conversion to obtain a signal having no DC component is performed. Is input to the light emission drive unit 10.
[0038]
FIG. 3 is a block diagram showing a configuration of the deflection angle control signal supply unit 8. The first light receiving element 6 of the light receiving / emitting unit 9 photoelectrically converts the pilot light from the counterpart device, and sends position information signals such as the presence / absence of received light, the amount of received light, and the light receiving direction to the deflection angle control signal supply unit 8. Supply. Based on the position information signal obtained from the light emitting / receiving unit 9, the deflection angle control signal supply unit 8 moves the reflection optical system 4 so as to align the optical axis of reception with the light from the counterpart device, and The calculation unit 13 obtains a deflection angle control signal by calculating the amount of movement, and the control unit 12 drives a driving means (not shown) of the reflection optical system 4 in the horizontal direction or the vertical direction based on the deflection angle control signal.
[0039]
The reception signal processing unit 38 converts the light of the data signal obtained by the second light receiving unit 39 into a signal suitable for the application. When the LAN is considered as an application of the indoor optical wireless transmission system described above, and the signal output to the external interface 38A is 100Base-FX, the received signal processing unit 38, as shown in the block diagram of FIG. NRZI / NRZ converter 111 (and PLL 112) performs NRZI / NRZ conversion on the signal received from 39, serial data is converted into parallel data by serial / parallel converter 113, and then scrambled by descrambler / descrambler 114. The processed signal is descrambled and the 4B / 5B decoder 115 decodes the 4B / 5B-encoded signal, and is input to the external interface 38A as a data signal. Note that the clock recovery circuit 116 recovers the timing interval of the clock included in the data signal.
[0040]
FIG. 6 is a configuration diagram in the case where a piezo actuator is used as a driving unit of the reflection optical system 4. The piezo actuator is an application of the piezoelectric effect of a piezo element. As shown in FIG. 6A, piezo actuators 19 are provided at four locations on the back side of the reflecting portion 18 of the reflective optical system 4 (in FIG. 2 are shown). Each piezo actuator 19 is expanded by a voltage applied to the electrode 20 as shown in FIGS. Therefore, the deflection angle with respect to the optical axis can be controlled by applying different voltages to the four piezoelectric actuators 19 to drive the reflecting optical system in the horizontal and vertical directions.
[0041]
The driving means in the present invention is not limited to a piezo actuator, and an actuator that can be controlled by current or voltage can be used as appropriate. Further, the reflection unit 18 of the reflection optical system 4 may have a curved surface, and the curved surface is driven to be uneven so that the deflection angle with respect to the optical axis is controlled.
[0042]
As the reflecting portion 18 of the reflecting optical system 4, a mirror generated by vapor-depositing Au (gold) on an optical resin can be used. The reflectance spectral characteristic of the Au film is shown in FIG. In addition, when a thin film that reflects only a specific wavelength is deposited, it also serves as a filter that cuts off extraneous light components in the received light.
[0043]
As the first light control element 3A and the second light control element 3B, for example, a non-polarizing beam splitter (hereinafter simply referred to as a beam splitter) can be used. It is also possible to use a beam splitter that transmits (reflects) only a specific wavelength, and in that case, it also serves as a filter that cuts off external light components in the received light.
[0044]
Next, with reference to FIG. 8 to FIG. 10, an operation when the deflection angle control signal supply unit 8 controls the deflection angle with respect to the optical axis based on the information obtained from the light emitting / receiving unit 9 will be described.
[0045]
FIG. 8 is a flowchart showing a control procedure of the reflection optical system 4 by the deflection angle control signal supply unit 8. FIG. 9 is an explanatory diagram showing a state in which a light receiving spot of pilot light received on the first light receiving element 6 configured by four-part PD moves in a stepwise manner. FIG. 10 is a block diagram showing a configuration for realizing the control procedure of FIG. 8 in the deflection angle control signal supply unit 8.
[0046]
Here, as shown in FIG. 9, the case where the first light receiving element 6 is configured by four divided photodiodes (PD_A, _B, _C, _D) and the reflection optical system 4 can be controlled in three dimensions. Take an example. Hereinafter, description will be made with reference to FIGS.
[0047]
The pilot light from the counterpart device is an optical signal having a certain frequency. In the light receiving and emitting unit 9, the PD (PD_A, B, C, D) of each of the four divided PDs (first light receiving elements 6) is obtained. The received light amount is photoelectrically converted and sent to the deflection angle control signal supply unit 8 as an electrical signal (SIG_A, B, C, D) having an amplitude corresponding to the received light amount (step S1). In the calculation unit 13 in the deflection angle control signal supply unit 8, the respective signal amplitudes are amplified by the amplifiers 21, 22, 23, and 24 (Step S 2), and the amplitude values are obtained by the A / D converters 25, 26, 27, and 28. A / D conversion is performed to obtain the signal level, that is, the amount of light received at each PD as a DC value (step S3). Subsequently, the difference in the light reception level between the PDs facing each other in the horizontal direction (Pan) and the vertical direction (Tilt) is calculated by a microprocessor 29 such as a microcomputer / DSP (step S4), and the light reception level difference is set to zero. Therefore, the movement direction and the movement amount of the reflection optical system 4 are calculated and sent to the control unit 12 (step S5 → S6, step S9 → S10). The control unit 12 D / A converts the values given by the D / A converters 30 and 31 and gives them to the drivers 32 and 33 as deflection angle control signals. The drivers 32 and 33 move the reflection optical system 4 in the horizontal and vertical directions. (Step S7 → S8, Step S11 → S12).
[0048]
Next, the movement of the light receiving spot on the quadrant PD will be described with reference to FIG. In the figure, reference numeral 6A denotes a light receiving spot on the quadrant PD when the pilot light is irradiated.
[0049]
In FIG. 9, in the step (1), first, the difference between the received light amounts of the PDs A and B facing each other in the vertical direction is calculated, and light is irradiated in the direction in which the difference becomes 0 (downward in FIG. 9). Thus, the reflecting optical system 4 is moved in the vertical direction. Next, in step (2), the difference between the received light amounts of the C and D PDs facing each other in the horizontal direction is calculated, and light is emitted in a direction to make the difference zero (right direction in FIG. 9). Next, the reflecting optical system 4 is moved in the horizontal direction.
[0050]
As described above, in the light receiving / emitting unit 9, since the transmission light and the reception light can be controlled coaxially by the first light control element 3A and the second light control element 3B, the light transmitted from the counterpart device having the same configuration. Is matched with the optical axis received by the present apparatus, the transmitted light of the present apparatus is applied to the counterpart apparatus. Similarly, the counterpart device also performs optical axis alignment, so that the transmission light from the counterpart device is irradiated onto the device, and the optical axes of the light receiving and emitting units 9 of the two devices match. Become.
[0051]
In the present embodiment, an example in which the first light receiving element 6 is configured by a four-divided PD is shown, but the number of divisions of the first light receiving element 6 may be three, or five, eight, etc. Further, the number of divisions may be further increased. In the present embodiment, an example in which the movement direction and the movement amount of the reflective optical system 4 are calculated so that the difference in the amount of received light at the PD becomes zero has been described. However, the movement direction and the movement amount are calculated by other algorithms. You may make it calculate.
[0052]
In the optical wireless transmission apparatus according to the first embodiment, the light of the transmission light and the reception light is controlled by controlling the deflection angle of the reflection optical system 4 based on the light received by the first light receiving element 6 for adjusting the optical axis. Since the axial alignment is performed coaxially, there are fewer movable parts and optical elements than the conventional device that rotates the light receiving device and the light emitting device at the same time, and the size of the device can be reduced. In comparison with a specific conventional apparatus, at least a volume ratio of 1/2 or less is achieved.
[0053]
Further, when the optical axis alignment is performed by the optical axis adjustment method of the optical wireless transmission apparatus according to the first embodiment, the search accuracy of the indoor optical wireless transmission apparatus using the conventional motor is about 0.2 [deg]. Whereas the speed is about 100 to 300 [rad / sec], in the apparatus according to the present embodiment, the search accuracy is 0.001 [deg] or less and the search speed is 500 [rad / sec] or more. In addition, high-speed optical axis alignment is realized. In this way, by using a configuration in which the light transmitted from the partner device and the optical axis received by the own device coincide with each other, even when a beam with a narrow directivity angle is used for the transmitted light as an indoor optical wireless transmission system, High-precision bidirectional communication can be performed.
[0054]
Furthermore, since the range in which the counterpart device can be searched is wide, it can be moved to various locations for indoor use.
[0055]
FIG. 11 is a schematic configuration diagram showing another configuration of the optical wireless transmission apparatus according to the first embodiment, and the same parts as those in FIG. 1 are denoted by the same reference numerals.
[0056]
The present embodiment shows a configuration in which the arrangement of the first light receiving unit 40 and the second light receiving unit 39 in FIG. That is, in the second light receiving unit 39, the data signal light incident from the counterpart device is reflected by the reflection optical system 4, reflected by the first light control element 3 </ b> A, and then received by the second light receiving element 36 through the lens 37. It is arranged at the position. In the first light receiving unit 40, the pilot light incident from the counterpart device is reflected by the reflection optical system 4, passes through the first light control element 3A, is reflected by the second light control element 3B, and then passes through the lens 5. The first light receiving element 6 is disposed at a position where light is received.
[0057]
Even when the arrangement of the first light receiving unit 40 and the second light receiving unit 39 is changed as in the present embodiment, the same effect as the light receiving and emitting unit 9 configured as shown in FIG. 1 can be obtained. it can.
[0058]
[Embodiment 2]
Next, the configuration of the optical wireless transmission apparatus according to the second embodiment will be described with reference to FIGS.
[0059]
FIG. 12 is a schematic configuration diagram of an optical wireless transmission apparatus according to the second embodiment. Parts equivalent to those in FIG. 1 are denoted by the same reference numerals.
[0060]
The present embodiment shows a configuration in which the arrangement of the second light receiving unit 39 and the light emitting unit 41 in FIG. 1 is exchanged. That is, in the light emitting unit 41, the emitted light emitted from the light emitting element 1 through the lens 2 is reflected by the second light control element 3B, then passes through the first light control element 3A, and is reflected by the reflection optical system 4. And are arranged so as to be transmitted as transmission light. In the first light receiving unit 40, the pilot light incident from the counterpart device is reflected by the reflection optical system 4, reflected by the first light control element 3A, and then received by the first light receiving element 6 through the lens 5. Are arranged as follows. Further, in the second light receiving unit 39, the data signal light incident from the counterpart device is reflected by the reflection optical system 4, passes through the first light control element 3 </ b> A and the second light control element 3 </ b> B, passes through the lens 37, and is second. The light receiving element 36 is arranged to receive light.
[0061]
Even when the arrangement of the second light receiving unit 39 and the light emitting unit 41 in FIG. 1 is changed as in the present embodiment, the same effect as that of the light receiving / emitting unit 9 configured as in FIG. 1 is obtained. Can do.
[0062]
Next, another configuration example of the optical wireless transmission apparatus according to the second embodiment will be described. In the optical wireless transmission device, the second light receiving element 36 of the second light receiving unit 39 receives the data signal light with high efficiency, thereby enabling data transmission at higher speed and longer distance. Therefore, in the configuration of the optical wireless transmission apparatus shown in FIG. 1 (Embodiment 1), it is necessary to make the reflection surface of the second light control element 3B equal to or larger than the area of light transmitted through the first light control element 3A. There is.
[0063]
FIG. 13 is a schematic configuration diagram illustrating another configuration example of the optical wireless transmission apparatus according to the second embodiment. In the present embodiment, the arrangement of the second light receiving unit 39 and the light emitting unit 41 is switched as in FIG. 12, and the reflection surface 3B-1 of the second light control element 3B further transmits the first light control element 3A. The second light control element 3B having a size smaller than that of FIG. 12 is arranged so as to be smaller than the light area S1.
[0064]
In the configuration of FIG. 13, since the light irradiated to the second light receiving element 36 is transmitted light of the second light control element 3B, the second light control element 3B is small and the reflecting surface 3B-1 is the first light control element. Even if the area S1 of the light passing through 3A is smaller than the area S1, the light that is not irradiated to the second light control element 3B is directly irradiated to the second light receiving element 36. For this reason, as shown in FIG. 12, it is possible to obtain an amount of received light equal to or greater than that when the reflection surface of the second light control element 3B is large. When the light emitting element 1 is a laser diode or the like, the directivity of the transmitted light is narrow, so the reflection surface of the second light control element 3B may be small.
[0065]
Further, in the present embodiment, since the second light control element 3B is downsized, the first light control element 3A can be brought closer to the second light control element 3B as shown in FIG. The entire light emitting / receiving unit 9 can be downsized, and the design of the light receiving / emitting unit 9 can be flexible.
[0066]
[Embodiment 3]
Next, the configuration of the optical wireless transmission apparatus according to the third embodiment will be described with reference to FIGS.
[0067]
FIG. 14 is a schematic configuration diagram of an optical wireless transmission apparatus according to the third embodiment. Parts equivalent to those in FIG. 1 are denoted by the same reference numerals.
[0068]
This embodiment shows a configuration in which the arrangement of the first light receiving unit 40 and the second light receiving unit 39 in FIG. 12 (Embodiment 2) is interchanged. That is, in the light emitting unit 41, the emitted light emitted from the light emitting element 1 through the lens 2 is reflected by the second light control element 3B, then passes through the first light control element 3A, and is reflected by the reflection optical system 4. And are arranged so as to be transmitted as transmission light. In the first light receiving unit 40, the pilot light incident from the counterpart device is reflected by the reflection optical system 4, passes through the first light control element 3A and the second light control element 3B, passes through the lens 5, and passes through the first light receiving element. 6 to receive light. Further, the second light receiving unit 39 receives the light of the data signal incident from the counterpart device by the reflection optical system 4 and is reflected by the first light control element 3A, and then received by the second light receiving element 36 through the lens 37. Are arranged to be.
[0069]
Even when the arrangement of the first light receiving unit 40 and the second light receiving unit 39 in FIG. 12 is switched as in the present embodiment, the same effect as the light receiving and emitting unit 9 configured as in FIG. 12 is obtained. Obtainable.
[0070]
Next, another configuration example of the optical wireless transmission apparatus according to the third embodiment will be described. In the optical wireless transmission device, it is necessary to efficiently irradiate the first light receiving element 6 with light in order to obtain more light information from the counterpart device when adjusting the optical axis. Therefore, in the configuration of the optical wireless transmission apparatus shown in FIG. 11 (Embodiment 1), it is necessary to make the reflection surface of the second light control element 3B equal to or larger than the area of light transmitted through the first light control element 3A. There is.
[0071]
FIG. 15 is a schematic configuration diagram illustrating another configuration example of the optical wireless transmission apparatus according to the third embodiment. In the present embodiment, the arrangement of the first light receiving element 40 and the second light receiving element 39 is interchanged as in FIG. 14, and the reflection surface 3B-1 of the second light control element 3B further replaces the first light control element 3A. The second light control element 3B having a size smaller than that of FIG. 14 is disposed so as to be smaller than the area S1 of the transmitted light.
[0072]
In the configuration of FIG. 15, since the light irradiated to the first light receiving element 6 is transmitted light of the second light control element 3B, the second light control element 3B is small and the reflecting surface 3B-1 is the first light control element. Even if it is smaller than the area S1 of the light passing through 3A, the light that is not irradiated to the second light control element 3B is directly irradiated to the first light receiving element 6. For this reason, as shown in FIG. 14, it is possible to obtain a received light amount equal to or greater than that when the reflection surface of the second light control element 3B is large. When the light emitting element 1 is a laser diode or the like, the directivity of the transmitted light is narrow, so the reflection surface of the second light control element 3B may be small.
[0073]
Further, in the present embodiment, since the second light control element 3B can be downsized, the first light control element 3A can be brought closer to the second light control element 3B as shown in FIG. The entire light emitting / receiving unit 9 can be downsized, and the design of the light receiving / emitting unit 9 can be flexible.
[0074]
[Embodiment 4]
Next, the configuration of the optical wireless transmission apparatus according to the fourth embodiment will be described with reference to FIGS.
[0075]
FIG. 16 is a schematic configuration diagram of an optical wireless transmission apparatus according to the fourth embodiment. Parts equivalent to those in FIG. 1 are denoted by the same reference numerals.
[0076]
The present embodiment shows a configuration in which the arrangement of the first light receiving unit 40 and the light emitting unit 41 in the configuration of FIG. 12 (Embodiment 2) is interchanged. That is, the light emitting unit 41 is configured so that the emitted light emitted from the light emitting element 1 through the lens 2 is reflected by the first light control element 3A, then reflected by the reflective optical system 4 and transmitted as transmission light. Has been placed. In addition, the first light receiving unit 40 reflects the pilot light incident from the counterpart device by the reflection optical system 4, passes through the first light control element 3 </ b> A, and is reflected by the second light control element 3 </ b> B. Then, the first light receiving element 6 is disposed so as to receive light. Further, in the second light receiving unit 39, the data signal light incident from the counterpart device is reflected by the reflection optical system 4, passes through the first light control element 3 </ b> A and the second light control element 3 </ b> B, passes through the lens 37, and is second. The light receiving element 36 is arranged to receive light.
[0077]
Even when the arrangement of the first light receiving unit 40 and the light emitting unit 41 in FIG. 12 is changed as in the present embodiment, the same effect as that of the light receiving and emitting unit 9 configured as shown in FIG. 12 is obtained. Can do.
[0078]
Next, another configuration example of the optical wireless transmission apparatus according to the fourth embodiment will be described. In the optical wireless transmission device, the second light receiving element 36 of the second light receiving unit 39 receives the data signal light with high efficiency, thereby enabling data transmission at higher speed and longer distance. Further, in order to obtain more information on the light from the counterpart device during the optical axis adjustment, it is necessary to irradiate the first light receiving element 6 with light efficiently. Therefore, in the configuration of the optical wireless transmission apparatus shown in FIG. 11 (Embodiment 1), it is necessary to make the reflection surface of the first light control element 3A equal to or larger than the area of the light reflected by the reflection optical system 4. is there.
[0079]
FIG. 17 is a schematic configuration diagram illustrating another configuration example of the optical wireless transmission apparatus according to the fourth embodiment. In the present embodiment, the arrangement of the first light receiving unit 40 and the light emitting unit 41 is switched as in FIG. 16, and the reflection surface 3A-1 of the first light control element 3A is reflected by the reflection optical system 4. The first light control element 3A having a smaller size than that of FIG. 16 is disposed so as to be smaller than the area S2.
[0080]
In the configuration of FIG. 17, the light irradiated to the first light receiving element 6 or the second light receiving element 36 is transmitted through the first light control element 3A and separated into transmitted light and reflected light by the second light control element 3B. Even if the first light control element 3A is small and the reflection surface 3A-1 is smaller than the area S2 of the light reflected by the reflection optical system 4, the light that is not irradiated on the first light control element 3A is The second light control element 3B is directly irradiated. For this reason, as shown in FIG. 16, it is possible to obtain an amount of received light equal to or greater than that when the reflection surface of the first light control element 3A is large. When the light emitting element 1 is a laser diode or the like, the directivity of the transmitted light is narrow, so the reflection surface of the first light control element 3A may be small.
[0081]
In the present embodiment, the first light control element 3A can be made closer to the second light control element 3B as shown in FIG. 17 by downsizing the first light control element 3A. The entire light emitting / receiving unit 9 can be downsized, and the design of the light receiving / emitting unit 9 can be flexible.
[0082]
[Embodiment 5]
Next, the configuration of the optical wireless transmission apparatus according to the fifth embodiment will be described with reference to FIGS.
[0083]
FIG. 18 is a schematic configuration diagram of an optical wireless transmission apparatus according to the fifth embodiment. Parts equivalent to those in FIG. 1 are denoted by the same reference numerals.
[0084]
The present embodiment shows a configuration in which the arrangement of the first light receiving unit 40 and the second light receiving unit 39 in the configuration of FIG. 16 (Embodiment 4) is interchanged. That is, the light emitting unit 41 is configured so that the emitted light emitted from the light emitting element 1 through the lens 2 is reflected by the first light control element 3A, then reflected by the reflective optical system 4 and transmitted as transmission light. Has been placed. In the first light receiving unit 40, the pilot light incident from the counterpart device is reflected by the reflection optical system 4, passes through the first light control element 3A and the second light control element 3B, passes through the lens 5, and passes through the first light receiving element. 6 to receive light. Further, the second light receiving unit 39 reflects the data signal light incident from the counterpart device by the reflection optical system 4, passes through the first light control element 3A, and is reflected by the second light control element 3B. The second light receiving element 36 is arranged so as to receive light through 37.
[0085]
Even when the arrangement of the first light receiving unit 40 and the second light receiving unit 39 in FIG. 16 is changed as in the present embodiment, the same effect as that of the light receiving / emitting unit 9 configured as shown in FIG. Obtainable.
[0086]
Next, another configuration example of the optical wireless transmission apparatus according to the fifth embodiment will be described. In the optical wireless transmission device, the second light receiving element 36 of the second light receiving unit 39 receives the data signal light with high efficiency, thereby enabling data transmission at higher speed and longer distance. Further, in order to obtain more information on the light from the counterpart device during the optical axis adjustment, it is necessary to irradiate the first light receiving element 6 with light efficiently. Therefore, in the configuration of the optical wireless transmission apparatus shown in FIG. 11 (Embodiment 1), it is necessary to make the reflection surface of the first light control element 3A equal to or larger than the area of the light reflected by the reflection optical system 4. is there.
[0087]
FIG. 19 is a schematic configuration diagram illustrating another configuration example of the optical wireless transmission apparatus according to the fifth embodiment. In the present embodiment, the arrangement of the first light receiving unit 40 and the second light receiving unit 39 is interchanged as in FIG. 18, and the reflection surface 3A-1 of the first light control element 3A is further reflected by the reflection optical system 4. The first light control element 3A having a size smaller than that of FIG. 18 is arranged so as to be smaller than the light area S2.
[0088]
In the configuration of FIG. 19, the light irradiated to the first light receiving element 6 or the second light receiving element 36 is transmitted through the first light control element 3A and separated into transmitted light and reflected light by the second light control element 3B. Even if the first light control element 3A is small and the reflection surface 3A-1 is smaller than the area S2 of the light reflected by the reflection optical system 4, the light that is not irradiated on the first light control element 3A is The second light control element 3B is directly irradiated. For this reason, as shown in FIG. 18, it is possible to obtain an amount of received light equal to or greater than that when the first light control element 3A has a large reflecting surface. When the light emitting element 1 is a laser diode or the like, the directivity of the transmitted light is narrow, so the reflection surface of the first light control element 3A may be small.
[0089]
In the present embodiment, the first light control element 3A can be made closer to the second light control element 3B as shown in FIG. 19 by downsizing the first light control element 3A. The entire light emitting / receiving unit 9 can be downsized, and the design of the light receiving / emitting unit 9 can be flexible.
[0090]
[Embodiment 6]
FIG. 20 is an explanatory diagram of a configuration example of the optical wireless transmission / reception device according to the sixth embodiment. By disposing the optical member of the light emitting / receiving unit 9 in the first to fifth embodiments on the same substrate 34, the optical wireless transmission device can be configured as a small module 35. For example, when a module having a size of about 5 mm square to 30 mm square is applied by applying a hologram pickup assembling technique or the like, it can be incorporated into a device such as a personal computer 42 as shown in FIG.
[0091]
As shown in the present embodiment, when the optical members of the light emitting / receiving unit 9 are integrally disposed on the same substrate, not only the apparatus can be reduced in size, but also the cost and the search time are reduced accordingly. Effects such as can be obtained. In addition, when using an integrated structure, the current IC microfabrication technology and hologram pickup assembly technology can be applied, enabling high-definition placement and easier adjustment of the transmission and reception optical axes. It will be something.
[0092]
[Embodiment 7]
Next, another configuration example of the first light control element 3A and the second light control element 3B will be described.
[0093]
As the first light control element 3A and the second light control element 3B, in addition to the beam splitters shown in the above-described embodiments, light that transmits light that is incident on one region and reflects light that is incident on another region A control element can be used.
[0094]
In the first embodiment, when the light emitting element 1 is a laser diode or the like, the directivity of the transmitted light is narrow, so that the transmission surfaces of the first light control element 3A and the second light control element 3B may be small. In this case, as shown in FIG. 22A, a light control element 51 having a transmission region 52 as a central portion through which light emitted from the light emitting element 1 transmits and a reflection surface 53 as all remaining portions (back surface) is used. be able to. The light control element 51 can be manufactured by vapor-depositing a reflective material in a region excluding the central portion of the transmission optical element serving as a base. In the light control element 51, the emitted light from the light emitting element 1 is transmitted through the transmission region 52, and the light received from the counterpart device is reflected by the reflecting surface 53 and guided to the first light receiving element 6. The transmission region 52 of the light control element 51 may be an opening. In this case, it can be manufactured by removing the central portion of the transmissive optical element as a base. FIG. 22A shows an example in which the light control element 51 and the first light receiving unit 40 are opposed to each other, but the same applies to the second light receiving unit 39.
[0095]
In addition, when the light emitted from the light emitting element 1 is reflected by the second light control element 3B as in the second embodiment, as shown in FIG. It is possible to use a light control element 61 in which the central portion where the emitted light is reflected is the reflective surface 62 and the remaining portion is the transmissive surface 63. The light control element 61 can be manufactured by masking all the remaining parts except the central part of the transmissive optical element as a base, and depositing a reflective material on the surface on which the reflective surface is formed. In the light control element 61, the light emitted from the light emitting element 1 is reflected by the reflection surface 62, and the light received from the counterpart device is transmitted through the transmission surface 63 and guided to the first light receiving element 6 through the lens 5. Become. FIG. 22B illustrates an example in which the light control element 61 and the first light receiving unit 40 are opposed to each other, but the same applies to the second light receiving unit 39.
[0096]
[Embodiment 8]
Next, laser output in each of the above embodiments will be described.
[0097]
In an optical wireless transmission device, light transmitted from the device is limited by safety standards. For example, in the case of a laser diode, its radiation intensity is defined by IEC 60825-1 (in Japan, JIS C6802: radiation safety standard for laser products). This reference limits the light output from the device. In the optical wireless transmission device shown in each of the above embodiments, when the light emitting element 1 is a laser diode, the output from the device is within the reference. The laser output of is sufficiently smaller than the level at which the laser diode can actually output. Therefore, in the case of the first embodiment, the transmission light can be made safe by changing the transmission / reflection ratio of the first light control element 3A and the second light control element 3B to lower the transmittance and increase the reflectance. It is possible to transmit at a high output level and to concentrate the received light on the first light receiving element 6 with high efficiency. For example, if the level at which the laser diode can output is 10 times the output level that can be transmitted from the apparatus, the transmittance of the second light control element 3B is 10% and the reflectance is 90%.
[0098]
In the light emitting element 1 shown in each of the above embodiments, the output level can be attenuated, and the transmitted light reflected by the reflection optical system 4 and transmitted to the outside of the apparatus is below the level limited by the safety standard. By being adjustable, high-speed bi-directional communication is possible with a level of strength that is safe for the eyes.
[0099]
In each of the embodiments described above, the pilot light for adjusting the optical axis is configured to be emitted from the light emitting element 1, but the pilot light is another light emitting element disposed inside or outside the light emitting / receiving unit 9. You may comprise so that it may radiate | emit from. The optical axis of the light emitting element is arranged so as to be coaxial or substantially parallel to the optical axis of the light emitting / receiving unit 9. Further, the light of the data signal emitted from the light emitting element 1 can be used as pilot light.
[0100]
【The invention's effect】
As described above, according to the present invention, the optical axis alignment of the transmission light and the reception light can be performed on the same axis by controlling the deflection angle of the reflection optical system. Compared to the conventional device that rotates, there are fewer movable parts, and the device can be made smaller. Further, even when a beam having a narrow directivity angle is used for the transmission light, it is possible to perform optical axis alignment with high accuracy and high speed. Furthermore, since the range in which the counterpart device can be searched is wide, it can be moved to various locations for indoor use.
[0101]
Therefore, when the optical wireless transmission device, the optical axis adjustment method of the optical wireless transmission device, the optical wireless communication method, and the optical wireless transmission system according to the present invention are applied to an indoor optical wireless transmission system, high-accuracy bidirectional communication is performed. Can be done.
[Brief description of the drawings]
FIG. 1 is a schematic configuration diagram of an optical wireless transmission apparatus according to a first embodiment.
FIG. 2 is a block diagram showing a configuration of a data supply unit.
FIG. 3 is a block diagram showing a configuration of a deflection angle control signal supply unit.
FIG. 4 is a block diagram showing a configuration of a signal processing unit.
FIG. 5 is a block diagram showing a configuration of a received signal processing unit.
FIG. 6A is a configuration diagram in the case where a piezo actuator is used as a driving unit of the reflective optical system. (B), (c) is explanatory drawing at the time of extending a piezo actuator.
FIG. 7 is an explanatory diagram showing reflectance spectral characteristics of an Au film.
FIG. 8 is a flowchart showing a control procedure of the reflection optical system by a deflection angle control signal supply unit.
FIG. 9 is an explanatory diagram showing a state in which a light receiving spot moves in a stepwise manner by a first light receiving element configured by a four-part PD.
10 is a block diagram showing a configuration for realizing the control procedure of FIG. 8 in a deflection angle control signal supply unit.
FIG. 11 is a schematic configuration diagram illustrating another configuration example of the optical wireless transmission apparatus according to the first embodiment.
FIG. 12 is a schematic configuration diagram of an optical wireless transmission apparatus according to the second embodiment.
FIG. 13 is a schematic configuration diagram illustrating another configuration example of the optical wireless transmission apparatus according to the second embodiment.
FIG. 14 is a schematic configuration diagram of an optical wireless transmission apparatus according to a third embodiment.
FIG. 15 is a schematic configuration diagram showing another configuration example of the optical wireless transmission apparatus according to the third embodiment.
FIG. 16 is a schematic configuration diagram of an optical wireless transmission apparatus according to a fourth embodiment.
FIG. 17 is a schematic configuration diagram illustrating another configuration example of the optical wireless transmission apparatus according to the fourth embodiment.
FIG. 18 is a schematic configuration diagram of an optical wireless transmission apparatus according to a fifth embodiment.
FIG. 19 is a schematic configuration diagram showing another configuration example of the optical wireless transmission apparatus according to the fifth embodiment.
FIG. 20 is an explanatory diagram showing a configuration example of an optical wireless transmission / reception apparatus according to the sixth embodiment.
FIG. 21 is an explanatory diagram when the optical wireless transmission apparatus according to the sixth embodiment is mounted on a personal computer.
FIG. 22 is an explanatory diagram showing another configuration example of the first and second light control elements. (A) is explanatory drawing at the time of making the central part which an emitted light permeate | transmits into a transmissive area | region, and making all the remaining parts into a reflective surface. (B) is explanatory drawing at the time of making the central part which an emitted light reflects into a reflective surface, and making all the remaining parts into a transmissive surface.
FIG. 23 is a schematic configuration diagram of a conventional indoor optical wireless transmission device.
[Explanation of symbols]
1. Light emitting element
2 ... Lens (first optical element)
3A: First light control element
3B ... second light control element
4 ... Reflective optical system
5 ... Lens (second optical element)
6 ... 1st light receiving element
7 ... Data supply section
7A ... External interface
8: Deflection angle control signal supply unit
9 ... Light emitting / receiving section
10: Light emission drive unit
11: Signal processor
12 ... Control unit
13. Calculation unit
18 ... Reflecting part
19 ... Piezo actuator
20 ... Electrode
21 ... Amplifier
21 ... Master unit
22 ... Light emitting part
23. Light emitting means
23A ... Pilot light
24 ... handset
24A ... Light receiving device
25-28 ... A / D converter
29 ... Microprocessor
30, 31 ... D / A converter
32, 33 ... Driver
34 ... Board
35 ... Module
36: Second light receiving element
37. Lens (third optical element)
38. Reception signal processing section
38A ... External interface
39: Second light receiving portion
40. First light receiving portion
41 ... Light emitting part
42 ... PC
51, 61 ... Light control element
101 ... 4B / 5B encoder
102 ... descrambling / scramble part
103 ... Parallel / serial converter
104 ... NRZ / NRZI converter
105, 112 ... PLL
111... NRZI / NRZ converter
113 ... Serial / parallel converter
114 ... Scramble / descramble part
115 ... 4B / 5B decoder
116: Clock recovery circuit

Claims (9)

A light emitting element that emits light modulated by a data signal or pilot light for adjusting the optical axis, a first optical element that shapes light emitted from the light emitting element into beam light that is close to parallel light, and a part of incident light First and second light control elements that reflect and transmit the rest, a reflection optical system that has incident means for reflecting incident light and that controls the deflection angle of the incident light with respect to the optical axis, transmitted from the counterpart device A second optical element for condensing the light, a first light receiving element for receiving the light condensed by the second optical element, a third optical element for condensing the light transmitted from the counterpart device, and the third optical A second light receiving element that receives the light collected by the element, and an irradiation area with respect to an optical axis direction of the light passing through the first light control element is light of the light incident on the second light control element The first and the first so as to be larger than the irradiation area in the axial direction. Together constitute a light control element, light emitted from the light emitting element is formed into the beam light close to parallel light by the first optical element after being reflected by the second optical control element, the first light control The light is transmitted through the element, reflected by the reflection optical system in a predetermined direction and transmitted as transmission light, light incident from the counterpart device is reflected by the reflection optical system, and part of the light is transmitted by the first light control element. After being reflected, the light is received by the first light receiving element through the second optical element, and the remaining light is transmitted through the first light control element, transmitted through the second light control element , and the second light control element. And a light receiving / emitting unit configured to be received by the second light receiving element through the third optical element,
A deflection angle control signal for controlling the deflection angle of the reflection optical system is calculated based on the pilot light received by the first light receiving element, and the drive means of the reflection optical system is controlled based on the deflection angle control signal. A deflection angle control signal supply unit,
The second light receiving element receives light from the counterpart device as a data signal, and controls the deflection angle of the reflective optical system based on the pilot light received by the first light receiving element, An optical wireless transmission apparatus characterized in that optical axes of light emitted from a light emitting element and light incident from the counterpart device are aligned. The optical wireless transmission device according to claim 1,
The light emitting / receiving unit is configured to convert the light emitted from the light emitting element into beam light close to parallel light by the first optical element, reflect the light by the second light control element, and then change the first light control element. Transmitted, reflected by the reflective optical system in a predetermined direction and transmitted to the counterpart device, light incident from the counterpart device is reflected by the reflective optical system, and part of the light is reflected by the first light control element Then, the light is received by the second light receiving element through the third optical element, and the remaining light is transmitted through the first light control element, transmitted through the second light control element , and of the second light control element. An optical wireless transmission device configured to pass around and to be received by the first light receiving element through the second optical element. A light emitting element that emits light modulated by a data signal or pilot light for adjusting the optical axis, a first optical element that shapes light emitted from the light emitting element into beam light that is close to parallel light, and a part of incident light First and second light control elements that reflect and transmit the rest, a reflection optical system that has incident means for reflecting incident light and that controls the deflection angle of the incident light with respect to the optical axis, transmitted from the counterpart device A second optical element for condensing the light, a first light receiving element for receiving the light condensed by the second optical element, a third optical element for condensing the light transmitted from the counterpart device, and the third optical A second light receiving element that receives the light collected by the element, and an irradiation area with respect to an optical axis direction of the light passing through the first light control element is light of the light incident on the second light control element The first and the first so as to be smaller than the irradiation area with respect to the axial direction. Together constitute a light control element, light emitted from the light emitting element is formed into the beam light close to parallel light by the first optical element after being reflected by the first optical control element, by the reflecting optical system Light reflected in a predetermined direction and transmitted to the counterpart device, light incident from the counterpart device is reflected by the reflective optical system, passes through the first light control element, and passes around the first light control element, Part of the light is reflected by the second light control element , then received by the first light receiving element through the second optical element, and the remaining light is transmitted through the first and second light control elements. A light emitting / receiving section configured to be received by the second light receiving element through the third optical element;
A deflection angle control signal for controlling the deflection angle of the reflection optical system is calculated based on the pilot light received by the first light receiving element, and the drive means of the reflection optical system is controlled based on the deflection angle control signal. A deflection angle control signal supply unit,
The second light receiving element receives light from the counterpart device as a data signal, and controls the deflection angle of the reflective optical system based on the pilot light received by the first light receiving element, An optical wireless transmission apparatus characterized in that optical axes of light emitted from a light emitting element and light incident from the counterpart device are aligned. In the optical wireless transmission device according to claim 3,
The light receiving and emitting unit, the light emitted from the light emitting element is formed into the beam light close to parallel light by the first optical element after being reflected by the first optical control element, the predetermined direction by the reflection optical system The light that is reflected to the partner device and transmitted from the partner device is reflected by the reflective optical system, passes through the first light control element, and passes around the first light control element. Is reflected by the second light control element , then received by the second light receiving element through the third optical element, and the remaining light is transmitted through the second light control element, and the second optical element. An optical wireless transmission apparatus configured to be received by the first light receiving element via In the optical wireless transmission device according to any one of claims 1 to 4,
The first light receiving element is constituted by a multi-divided light receiving element,
The deflection angle control signal supply unit is configured to calculate a moving direction and a moving amount of the reflection optical system based on a light receiving amount in each divided region of the light receiving element, and a moving direction calculated by the calculating unit. Control means for driving the reflecting optical system driving means in a horizontal direction or a vertical direction based on the amount of movement to align the optical axis of the light emitted from the light emitting element and the light incident from the counterpart device;
An optical wireless transmission device comprising: In the optical wireless transmission device according to any one of claims 1 to 5,
An optical wireless transmission apparatus, wherein the constituent members of the light emitting / receiving unit are integrally arranged on the same substrate . In the optical axis adjustment method of the optical wireless transmission device according to claim 5,
  The light incident from the counterpart device is received by the first light receiving element, and the moving direction and the moving amount of the reflective optical system are calculated based on the amount of light received by each light receiving element constituting the first light receiving element. Based on the moving direction and the moving amount, the driving means of the reflective optical system is driven in the horizontal direction or the vertical direction, thereby aligning the optical axis of the light emitted from the light emitting element and the light incident from the counterpart device. An optical axis adjustment method for an optical wireless transmission device. The optical wireless transmission device according to any one of claims 1 to 6 is disposed as a first optical wireless transmission device and a second optical wireless transmission device facing each other at a predetermined interval, and the optical wireless transmission device according to claim 7 is also provided. An optical wireless communication method characterized in that, after optical axis alignment is performed by an optical axis adjustment method, bidirectional communication is performed between the first and second optical wireless transmission devices. An optical wireless transmission system in which the optical wireless transmission device according to any one of claims 1 to 6 is disposed as a first and second optical wireless transmission device facing each other at a predetermined interval,
  An optical axis alignment of the first and second optical wireless transmission apparatuses by the optical axis adjustment method of the optical wireless transmission apparatus according to claim 7, and then between the first and second optical wireless transmission apparatuses. An optical wireless transmission system characterized by performing bidirectional communication.

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