JPH06303198A - Wireless parallel optical transmission equipment - Google Patents

Abstract

(57) [Abstract] [Purpose] To achieve high-speed transmission of a large amount of data in a wireless parallel optical transmission device. [Configuration] Parallel optical transmitter 11 and parallel optical receiver 12
From it, the parallel optical transmission device 11, a one-dimensional array and constant pitch length P ₁ a plurality of light emitting elements arranged in one
4, each of the light emitting elements 14 is provided with a microlens 17 for condensing light from the light emitting element 14 so that the light does not overlap the light of the adjacent light emitting element 14, and the parallel light receiving device 12 includes The one-dimensional array and the light-emitting element 14 are longer than the one-dimensional array-shaped length of the light-emitting element 14.
Has a plurality of light receiving elements 20 arranged at a pitch P ₂ which is half the pitch length P ₁ of the light emitting elements 14 and the length l _{4 in the} direction perpendicular to the one-dimensional array direction of the light receiving elements 20 is the pitch of the light emitting elements 14. It is characterized in that it has a shape longer than the length P ₁ .

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wireless parallel optical transmission apparatus for wirelessly transmitting and receiving signals between devices placed in a short distance by using an optical signal, for example, a personal computer,
O for word processors, printers, computers and peripherals
In particular, the present invention relates to a wireless parallel optical transmission device that performs wireless connection in parallel between small and portable devices, or data transmission / reception between an IC card, an optical memory card, etc. and a main device among signals exchanged between devices A. .

[0002]

2. Description of the Related Art Conventionally, signals are exchanged between small and portable devices by connecting them with a connector or a metal cable.

FIG. 11 is a diagram showing a conventional example. In this conventional example, signals are exchanged between the main body portable personal computer 1 and the printer unit (or external memory device such as FDD / HDD) 2 via the connector 3.

FIG. 12 is a diagram showing another conventional example. In this conventional example, signals are exchanged between the small information devices 4 by the cable 5 with a connector.

[0005]

Generally, in information equipment aimed at small size and portable type, a minimum system is incorporated in the main body device in order to improve the function because of its portability. Generally, a peripheral device is prepared. Therefore, it is necessary to provide an interface for connection between these devices, and it is inevitable that the size of the device will be correspondingly increased by the connector for this interface.

In order to speed up signal transmission, parallel transmission is better than serial transmission, and the connector is
It requires multiple pins, and there is a limit to size reduction.

Further, when transmitting various data and signals between devices, it is necessary to make a cable connection or a connector connection one by one, and the more frequently the data is connected, the more troublesome it is. Therefore, a method using wireless optical transmission that does not require connection has been considered, but in the current wireless optical transmission, serial transmission is performed with one transmission channel. Therefore, there is a problem that the data transmission speed is slow and it takes time to transmit a large amount of data. As a way to improve this, to increase the number of channels,
There is a problem of crosstalk between channels, a problem of alignment of light emission and light reception, and there is a drawback that the size becomes large.

[0008] For example, as a method of high-speed wireless optical transmission, there can be mentioned multi-channelization, but normally the pitch of the array for multi-channeling is determined by the resolution accuracy on the light emitting side. Both the light-receiving element and the light-emitting element depend on the accuracy of the semiconductor process, but the beam must be optically narrowed down on the light-emitting side. This is because the beam spreads with the distance when the laser light is not used, and even when the laser is used, the array pitch cannot be made as small as that of the light receiving element in the existing technology. In the case where the number of channels is simply increased, as shown in FIG. 13A, in order to avoid crosstalk with adjacent channels, the width a of one emission beam 6 in the horizontal direction is set to the horizontal direction. If the tolerance for device alignment is Δl, the pitch length P of the array is
Requires a + Δl. In other words, the alignment error is 1m
If the beam width a is ignored, the array pitch P must be at least 1 mm or more even if the beam width a is ignored. If you want to allow a misalignment of about 5 mm when you want to roughly align the equipment, the array pitch P must be at least 5 mm, and the array length must be 9 channels and 45 mm or more. If the length is 10 mm, the array length is 9
0 mm or more is required. If a structure that enables positioning with a boss etc. is used, it is possible to use a relatively small size.
A large size is required in a configuration in which devices are simply butted against each other. In addition, in FIG. 3A, 7 is a light receiving element.

In the above, the emission beam width a is reduced to
Although there is a case where the positional deviation is absorbed by the size of the light receiving element, a case where the emission beam width a is made large as shown in FIG. 13B can be considered, but the necessary pitch P with respect to the margin Δl for alignment is Δl or more, The array length of 90 mm or more (for parallel transmission of 9 channels as in the previous example) is required for the positional deviation tolerance of 10 mm. still,
In FIG. 3B, 6 is a light emitting beam, and 7 is a light receiving element.

In view of the above problems, the wireless parallel optical transmission apparatus of the present invention improves crosstalk between channels,
It is an object of the present invention to provide a wireless parallel optical transmission device capable of transmitting a large amount of data in parallel at high speed by facilitating alignment and enabling miniaturization.

[0011]

A wireless parallel optical transmission apparatus according to claim 1 of the present invention comprises a parallel optical transmission apparatus and a parallel optical reception apparatus, and the parallel optical transmission apparatus is in a one-dimensional array and has a certain size. A plurality of light emitting elements arranged at a pitch length of, each light emitting element is provided with means for controlling light so that light from the light emitting element does not overlap with light of an adjacent light emitting element, and the parallel light The receiving device has a plurality of light-receiving elements arranged in a one-dimensional array longer than the length of the one-dimensional array of the light-emitting elements and arranged at a pitch length half the pitch length of the light-emitting elements. The length in the direction perpendicular to the original array direction is longer than the pitch length of the light emitting elements.

A wireless parallel optical transmission device according to a second aspect of the present invention comprises a parallel optical transmission device and a parallel optical reception device, and the parallel optical transmission devices are arranged in a two-dimensional array with a certain pitch length. The parallel light receiving device has a plurality of light emitting elements, each light emitting element is provided with means for controlling light so that light from the light emitting element does not overlap with light of an adjacent light emitting element. A plurality of light receiving elements arranged in a two-dimensional array whose length in the direction is longer than the length of the two-dimensional array of the light emitting elements and in a pitch length which is half the pitch length of the light emitting elements. It is characterized by.

[0013]

According to the above structure, in the wireless parallel optical transmission device according to claim 1 of the present invention, each light emitting element controls light so that light from the light emitting element does not overlap with light of an adjacent light emitting element. Since there is a means for doing so, crosstalk between channels can be eliminated. Further, since the light receiving elements are arranged at a pitch which is half the arrangement pitch of the light emitting elements, even if the light emitting beam from the light emitting element is displaced to any position in the one-dimensional array direction, at least 1
One of the light receiving elements corresponds to the emitted light beam and can receive the beam, and the alignment accuracy of the light receiving and emitting element can be eliminated. Furthermore, by making the length of the light-receiving element array in the one-dimensional array direction longer than the length of the light-emitting element array in the one-dimensional array direction, the alignment of the parallel transmitter and the parallel receiver in the array direction can be facilitated. In addition, since the length in the direction perpendicular to the one-dimensional array direction of the light receiving element is longer than the pitch length of the light emitting element,
The alignment of the parallel optical transmitter and the parallel optical receiver in the direction perpendicular to the array direction can be easily performed. In addition, the above configuration can make the size of the wireless parallel optical transmission device compact. Therefore, a large amount of data can be transmitted in parallel at high speed.

Further, in the wireless parallel optical transmission device according to the present invention, each of the light emitting elements includes means for controlling the light so that the light from the light emitting element does not overlap the light of the adjacent light emitting element. , It is possible to eliminate crosstalk between channels. Further, since the light receiving elements are arranged at a pitch that is half the pitch of the light emitting elements, no matter what position the emission beam from the light emitting elements is shifted,
At least one of the light receiving elements corresponds to the emitted light beam and can receive the light beam, and the alignment accuracy of the light emitting and receiving element can be eliminated. Further, by making the lengths of the light receiving element array in the vertical and horizontal directions longer than the lengths of the light emitting element array in the vertical and horizontal directions, the alignment of the parallel optical transmitter and the parallel optical receiver can be facilitated. In addition, with the above configuration, the size of the wireless parallel optical transmission device can be made compact. Therefore, a large amount of data can be transmitted in parallel at high speed.

[0015]

FIG. 1 is a view showing an embodiment of the present invention,
The figure (a) is a front view and the figure (b) is a side sectional view.

As shown in FIG. 1, the wireless parallel optical transmission apparatus of the present invention comprises a parallel optical transmission apparatus 11 and a parallel optical reception apparatus 12.
The parallel optical transmitter 11 includes a light emitting element 14 such as a semiconductor laser chip on a substrate 13 in a one-dimensional array,
Moreover, they are arranged at a constant pitch p ₁ and the glass plate 15
Is fixed by an acrylic adhesive 16, and further, a glass plate 18 on which microlenses 17 are formed in a one-dimensional array is fixed by the acrylic adhesive 16. The light emitting element 14 and the microlens 17 are arranged so as to be paired with each other. The microlens 17 is formed, for example, by vapor-depositing Ti, opening a circular window by photolithography, immersing it in a melt of nitrate of monovalent ions and heating it, and diffusing cations in the melt into the glass. Then, ion exchange is performed to generate a refractive index distribution in the glass to form the lens 17. In the case of this embodiment, as shown in FIG. 2, the microlens 17 has a pitch p ₁ of 500 μm, an effective light emission size d of 100 μm by the light emitting element 14, and a focal length of 2 mm, the distance l ₁ The emission beam diameter D at a position of 10 mm or less is configured to be within 500 μm.

As described above, the optical signal from the light emitting element 14 is controlled by the microlens 17 so that the pitch P ₁ is 500 μm and the emission beam diameter D is within 500 μm.
That is, by setting the pitch P ₁ ≧ the emission beam diameter D, the emission beam from the adjacent light emitting element 14 does not overlap, and the crosstalk between channels can be improved.

As shown in FIG. 1, the parallel optical receiver 12 has the following structure.
A structure in which the light receiving elements 20 are arranged on the substrate 19 in a one-dimensional array at a pitch p ₂ which is half the arrangement pitch p ₁ of the light emitting elements 14 and is covered with a transparent epoxy resin 21. The length of the light-receiving element array is longer than the length of the light-emitting element array by (l ₂ + l ₃ ). Further, the length l ₄ of the effective light receiving portion of the light receiving element 20 is longer than the arrangement pitch p ₁ of the light emitting elements 14 with respect to the direction perpendicular to the light receiving element array direction.

The wireless parallel optical transmission device having the above structure is
For example, as shown in FIG. 4, the parallel optical transmitter 11 and the parallel optical receiver 12 are built in the portable devices 22 and 23, and the signals are transmitted and received wirelessly by making them face each other.

When an LED is used as the light emitting element 14 of the parallel optical transmitter 11, the distance between the devices 22 and 23 is 10 mm or less, which is a relatively short distance, because of the limit of the light condensing property of the LED. Although the device 22 and 23 are mainly used facing each other, by using a semiconductor laser as the light emitting element 14, long-distance transmission is possible while narrowing the beam, and wireless transmission between indoor devices is possible. .

In the above structure, the light receiving elements 20 are arranged in a one-dimensional array and the arrangement pitch P of the light emitting elements 14 is set.
By arranging at a pitch P ₂ that is half the length of ₁ , even if the light emitting beam from the light emitting element 14 is displaced to any position in the one-dimensional array direction, as shown in FIG. Only two light receiving elements 20 can correspond to 24, or at least one light receiving element 20 can correspond to the emission beam 24 as shown in FIG. 4B. Therefore, the light emitting / receiving element 14 between the devices 22 and 23,
The alignment accuracy of 20 can be eliminated.

Further, by making the length of the light receiving element array longer than the length of the light emitting element array, the lengthened portion becomes a permissible width for the positional deviation of the devices 22 and 23 to be transmitted / received, and the position adjustment is performed. Will be easier. Further, in the present embodiment, for example, if the allowable value for the positional deviation in the lateral direction of the device is 5 mm and the lateral pitch length of the emission beam is 500 μm, a total of 9 channels of 8-bit data and 1 clock are transmitted in parallel. In the case of, the total length of the light receiving element array is 9.5 mm (0.5 mm × 9 + 5 m
m), and the required length 4 of the entire light-receiving element array when simply combining the same number of light-emitting / receiving pairs shown in FIG.
Compared with 9.5 mm ((0.5 mm + 5 mm) × 9),
Since it is only about 1/5, the size can be made compact.

Further, since the light receiving element is configured such that the length l ₄ of the effective light receiving portion of the light receiving element 20 is longer than the arrangement pitch P ₁ of the light emitting elements 14 with respect to the direction perpendicular to the one-dimensional array direction, The positional deviation in the direction perpendicular to the array direction in the alignment of the devices 22 and 23 can be absorbed.

As described above, in the wireless parallel optical transmission system according to the present embodiment, at least one light receiving element can receive the optical signal from the light emitting element, which eliminates the need for positioning accuracy of the light receiving and emitting elements and the number of channels. By eliminating crosstalk between channels when the number of channels is increased, the parallel optical transmitter and the parallel optical receiver can be easily aligned, and a compact size can be achieved. Therefore, a large amount of data such as image information can be stored. It can be transmitted at high speed.

In the above-mentioned wireless parallel optical transmission device, the microlens is used as a means for controlling the light emitting beam from the light emitting element, but a partition plate is used between the light emitting elements so as not to overlap with the light emitting beam from the adjacent light emitting elements. It is also possible to configure so.

Next, the operation of the wireless parallel optical transmission device comprising the parallel optical transmitter 11 and the parallel optical receiver 12 of the present invention will be described.

First, prior to transmitting / receiving a signal, the light emitting element 14 corresponding to the channel 1 in the parallel optical transmitter 11 emits light. Then, in response to this light emission, the parallel light receiving device 1
Light receiving element 2 having the highest light receiving output among the light receiving elements 20 in 2
By selecting 0, this light receiving element 20 is determined as channel 1. At this time, if there is the same light receiving output next to each other,
It doesn't matter which one you choose. In the same manner, channel 2 and channel 3 are sequentially assigned, followed by a one-to-one correspondence between all the light emitting channels and the light receiving channels.

After that, the transmission data is transmitted by the light emitting element 14 in the parallel optical transmitter 11 in parallel optical transmission on all channels simultaneously in parallel, and the optical signal of the previously determined light receiving channels in the parallel optical receiver 12 is transmitted. Light receiving element 2 for all channels
Received by 0. The above operation enables parallel optical transmission.

Another operation of the wireless parallel optical transmission device will be described below. FIG. 5 is a diagram showing the circuit configuration. As an example, a configuration for parallel transmission of 8-bit digital data will be described.

As shown in FIG. 5, on the transmitting side, the CPU 25 outputs to the drive circuit section 26 a transmission signal for a total of 9 channels of an 8-bit digital data signal and a clock signal. The drive circuit unit 26 is composed of a drive circuit for LEDs for 9 channels, and drives each LED in the parallel optical transmitter 11 according to a transmission signal. As the signal transmission timing, as shown in FIG. 6, the clock signal is transmitted first,
Then, with a delay of T / 2 with respect to the clock width T, word signals W1, W2, W3 of 8-bit (D1 to D8) configuration,
Are sequentially transmitted. These are transmitted together with the clock signal with a delay of 2 words for 2 words during the clock period (2T).

On the receiving side, the photocurrent corresponding to the amount of light received by each light receiving element (PD) in the parallel light receiving device 12 is converted into a current-voltage by the amplifier circuit 27, voltage-amplified, and sent to the differential amplifier circuit 28. And the differential amplifier circuit 28
The value is compared with a predetermined reference voltage value, and if it is larger than the reference voltage value, the digital value 1 is sent to the multiplexer 29, and if it is smaller, it is sent to the multiplexer 29. The multiplexer 29 is configured to obtain a 9-bit output corresponding to the control signal C from a 36-bit input. As the configuration of the multiplexer 29, the control signal C has a 5-bit configuration, and the head bit (DB) of the output sequence is selected from the input data DB1 to DB36 according to the control signal input value (1 to 32).
1 to DB32) are determined. The circuit configuration is such that the odd-numbered data, counting from the first bit, is sequentially selected for 9 bits. As a receiving operation, when a signal is detected on any channel by the OR circuit 30 for all data, the signal is input to the CPU 31 through the OR circuit 30, and the operation is started by using the input signal as a trigger. The CPU 31
In response to the control signal C, the data is sequentially fetched through the multiplexer 29 for every 9 channels. DB1, DB
3, DB5, DB7, DB9, DB11, DB13, D
B15, DB17 followed by DB2, DB4, DB6, D
B8, DB10, DB12, DB14, DB16, DB
18, followed by DB19, DB21, DB23, DB2
5, DB27, DB29, DB31, DB33, DB3
5, then DB20, DB22, DB24, DB26,
DB28, DB30, DB32, DB34, DB36 are taken in. If there is only one channel in which 1 signal is detected in all data, that channel is used as a clock channel, and if there are two channels, any one channel is set to 3
In the case of the number of channels, the central channel is used as the clock channel (for example, in the case of FIG. 4A, the number of 1 signal detection channels is 2, and in the case of FIG. 4B, the number of 1 signal detection channels is 1). Or, it becomes three.) Hereinafter, the channels are determined as data channels every other channel. For example, if the clock data is detected by DB6, DB8 is made to correspond to D1, DB10 is made to correspond to D2, and every other piece of data is sequentially made to correspond to D8, and the last DB22 is made to correspond to D8. As described above, the correspondence between the subsequent transmission clock and the channel corresponding to 8 bits of the transmission data is determined. In the subsequent data reception, in FIG. 6, W1 is sequentially read at the falling timing of the clock signal and W2 is read at the rising timing of the next clock signal. When the clock signal disappears, the data ends. In FIG. 6, the process ends with W (N + 1). If W (N + 1) is unnecessary, all 0 signals may be transmitted.

As described above, by transmitting the clock signal prior to the data signal and receiving the clock signal, the clock signal reception channel is determined, and the parallel data signal transmitted subsequent to the clock signal is determined. As the receiving channels, the light receiving elements 20 are arranged at a half pitch with respect to the pitch of each light emitting element 14. Therefore, every other channel selected from the clock signal receiving channels is selected as a receiving channel for the parallel data signal. By determining as, it becomes possible to correspond to each channel of the parallel data signal.

FIG. 7 is a view showing another embodiment, in which FIG. 7A is a front sectional view and FIG. 7B is a side sectional view. This embodiment will be described only on the points different from the embodiment shown in FIG.

As shown in FIG. 7, in the wireless parallel optical transmission system of the present embodiment, the light emitting elements 14 are arranged in a two-dimensional array with a constant pitch length P ₁ , and the light emitting elements 14 are arranged on the light emitting elements 14. Two-dimensional array microlenses 17 are provided so that the light from 14 does not overlap the adjacent light-emitting elements 14, and the light-receiving element 20 has a two-dimensional array and has the above-mentioned light-emitting elements 1.
Are arranged in four half pitch length P ₂ of the pitch length P _1, further vertical and horizontal lengths of the two-dimensional array light receiving element 20 from the vertical and horizontal lengths two-dimensional array of the light emitting element 14 Is also long.

According to the above construction, assuming that the diameter of the light emitting beam from the light emitting element is equal to the pitch length of the light emitting element, no matter how the irradiation position of the light emitting beam deviates, as shown in FIG. 8A. , Four light receiving elements 14 can correspond to the emission beam 24, or, as shown in FIG.
At least one light receiving element 14 for the emitted beam 24
Can handle. Alternatively, as shown in FIG. 8C and FIG. 8D, at least two light receiving elements 14 can correspond to the emission beam 24. Therefore, the light emitting / receiving element 1
The alignment accuracy of 4 and 20 can be eliminated.
The irradiation shape of the emission beam 24 in FIG. 8 is actually a substantially circular shape, but here it is a substantially square shape.

Further, by making the lengths of the light receiving element array in the vertical and horizontal directions longer than the lengths of the light emitting element array in the vertical and horizontal directions, the lengthened portion is aligned with the devices 22 and 23 to be transmitted and received. This is an allowable width for the misalignment, and the misalignment in the vertical and horizontal directions can be absorbed, so that the devices 22 and 23 can be easily aligned.

As described above, in the wireless parallel optical transmission apparatus according to the present embodiment, at least one light receiving element can receive the optical signal from the light emitting element, the alignment accuracy of the light receiving and emitting elements is unnecessary, and the number of channels is increased. By eliminating crosstalk between channels when the number of channels is increased, the parallel optical transmitter and the parallel optical receiver can be easily aligned, and a compact size can be achieved. Therefore, a large amount of data such as image information can be stored. It can be transmitted at high speed.

Next, the operation of the wireless parallel optical transmission system of this embodiment will be described.

First, prior to transmitting / receiving a signal, the light emitting element 14 corresponding to the channel 1 in the parallel optical transmitter 11 emits light. Then, in response to this light emission, the parallel light receiving device 1
Light receiving element 2 having the highest light receiving output among the light receiving elements 20 in 2
By selecting 0, this light receiving element 20 is determined as channel 1. At this time, it does not matter which one is selected as long as it has the same light receiving output in the neighboring areas. In the same manner, channel 2 and channel 3 are sequentially assigned, followed by a one-to-one correspondence between all the light emitting channels and the light receiving channels.

After that, the transmission data is transmitted in parallel by the light emitting element 14 in the parallel optical transmitter 11 in parallel on all channels simultaneously, and this optical signal is transmitted to the previously determined light receiving channels in the parallel optical receiver 12. Light receiving element 2 for all channels
Received by 0. The above operation enables parallel optical transmission.

In the above embodiments, both the light emitting element 14 and the light receiving element 20 are shown as a multi-chip structure in which one chip is one element. These are the light emitting chip shown in FIG.
Like the light receiving chip shown in 0, a plurality of elements are arranged in an array.
It is also possible to use one chip having a structure configured in the chip.

[0042]

As described above, according to the wireless parallel optical transmission apparatus of the present invention, at least one light receiving element can receive the optical signal from the light emitting element, which eliminates the need for positioning accuracy and reduces the number of channels. By eliminating crosstalk between channels when the number of channels increases, the parallel optical transmitter and the parallel optical receiver can be easily aligned, and the size can be made compact. As a result, a large amount of data such as image information can be transmitted at high speed.

[Brief description of drawings]

FIG. 1 is a view showing an embodiment of the present invention, FIG. 1 (a) is a front view, and FIG. 1 (b) is a side sectional view.

FIG. 2 is a partially enlarged view of the parallel optical transmission device shown in FIG.

3 is a configuration diagram of signal transmission between devices using the wireless parallel optical transmission device shown in FIG.

4 is a diagram showing a relationship between a light emitting beam width and a light receiving element size in signal transmission / reception by the wireless optical transmission device shown in FIG.

5 is a circuit configuration diagram in another operation of the wireless parallel transmission apparatus shown in FIG.

6 is a diagram showing an example of transmission timings of a clock signal and a data signal in the circuit configuration shown in FIG.

FIG. 7 is a diagram showing another embodiment of the present invention, FIG.
Is a front sectional view, and FIG. 6B is a side sectional view.

8 is a diagram showing a relationship between a light emitting beam width and a light receiving element size in signal transmission / reception by the wireless optical transmission device shown in FIG.

FIG. 9 is a configuration diagram of another light emitting chip in the light emitting element.

FIG. 10 is a configuration diagram of another light receiving chip in the light receiving element.

FIG. 11 is a diagram showing a conventional example.

FIG. 12 is a diagram showing another conventional example.

FIG. 13 is a diagram showing a relationship between a light emitting beam width and a light receiving element size in signal transmission / reception by general wireless optical transmission.

[Explanation of symbols]

11 parallel optical transmitter 12 parallel optical receiver 14 light emitting element 17 microlens 20 light receiving element P ₁ , P ₂ pitch length

Claims (3)

[Claims] 1. A parallel optical transmitter and a parallel optical receiver, wherein the parallel optical transmitter has a plurality of light emitting elements arranged in a one-dimensional array and at a certain pitch length. Each of the parallel light receiving devices is provided with a one-dimensional array longer than the length of the one-dimensional array of the light-emitting elements. It has a plurality of light receiving elements arranged in an array and at a pitch length half the pitch length of the light emitting elements, and the length in the direction perpendicular to the one-dimensional array direction of the light receiving elements is greater than the pitch length of the light emitting elements. A wireless parallel optical transmission device characterized by having a long shape. 2. A parallel optical transmitter and a parallel optical receiver, wherein the parallel optical transmitter has a plurality of light emitting elements arranged in a two-dimensional array and having a certain pitch length. Each of the parallel light receiving devices is provided with a two-dimensional array of light emitting elements having vertical and horizontal lengths so that light from each light emitting element does not overlap with light of an adjacent light emitting element. Wireless parallel optical transmission device having a plurality of light receiving elements arranged in a two-dimensional array longer than the lengths in the vertical and horizontal directions and arranged at a pitch length half the pitch length of the light emitting elements. 3. The wireless parallel optical transmission device according to claim 1, wherein the means for controlling the light from the light emitting element is a lens.