JP2008282253A - Optical transmitter, optical receiver, and optical communication device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To take an image at a proper frame rate for extracting transmission information. <P>SOLUTION: A drive circuit 18c of this optical transmission device 12 performs blink drive of each of transmission information-transmitting LEDs 24<SB>1</SB>-24<SB>n</SB>in synchronization with a signal of a prescribed frequency f [Hz] based on the transmission information to make signal light be output from each of the transmission information-transmitting LEDs 24<SB>1</SB>-24<SB>n</SB>. A drive circuit 18b of the optical transmission device 12 performs blink drive of a frequency information-transmitting LED 22 according to a signal expressing the prescribed frequency f [Hz] to output frequency light from the frequency information-transmitting LED 22. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an optical transmission device that transmits signal light, an optical reception device that receives signal light, and an optical communication device that performs optical communication by transmitting and receiving signal light.

  Conventionally, a vehicular communication device that performs optical communication between vehicles is known (see, for example, Patent Document 1).

In the vehicular communication device described in Patent Document 1, signal light is emitted by blinking an auxiliary lamp provided on the front end side of the transmission-side vehicle, and the emitted signal light is transmitted to the rear portion of the reception-side vehicle. The signal is received by the provided back-eye camera, the received signal light is demodulated by the decoder, the signal included in the signal light is read, and the read signal is output to the display panel. Thereby, communication between vehicles is performed.
JP 2004-326705 A

  However, in the vehicle communication device described in Patent Document 1, since the blinking frequency of the signal light is not grasped on the receiving side, the frame rate higher than the appropriate frame rate for satisfying the sampling theorem (Nyquist theorem) with the back-eye camera. Therefore, there is a problem that the back-eye camera is loaded more than necessary.

  The present invention has been made to solve the above problems, and provides an optical transmission device, an optical reception device, and an optical communication device that can capture images at an appropriate frame rate for extracting transmission information. With the goal.

  In order to achieve the above object, an optical transmitter according to a first aspect of the present invention is configured to drive the first light emitting element by blinking in synchronization with a signal having a predetermined frequency based on transmission information. First driving means for outputting signal light from the second light emitting device, and second driving for outputting frequency light from the second light emitting element by blinking the second light emitting element in accordance with the signal representing the predetermined frequency. And means.

  According to the optical transmission device of the present invention, since the frequency light is output from the second light emitting element, the frame rate is determined when the reception side grasps the predetermined frequency of the transmission information by receiving the frequency light. By setting the value to at least twice the predetermined frequency, it is possible to capture an image at an appropriate frame rate for extracting transmission information.

  In the optical communication device according to the present invention, the third light emitting element is driven to blink, whereby light indicating the start and end of transmission information represented by the signal light output from the first light emitting element is transmitted to the third light emitting element. Third driving means for outputting from the light emitting element may be further included. Thereby, even if the transmission information is variable, the transmission information can be extracted from the signal light in accordance with the start and end timings indicated by the light on the receiving side.

  The optical transmission device according to the present invention further includes a plurality of light emitting diodes provided at a rear portion of the vehicle as at least one of the first light emitting element, the second light emitting element, and the third light emitting element. A light emitting diode of a brake light or a light emitting diode of a traffic light equipped with a plurality of light emitting diodes can be used.

  In the optical transmission device according to the present invention, the wavelength band of the light output from the first light emitting element, the light output from the second light emitting element, and the light output from the third light emitting element Can be different from each other. As a result, when a photographing device such as an optical communication camera having sensitivity in each of the wavelength bands of light from the first light emitting element, the second light emitting element, and the third light emitting element is provided on the receiving side. In addition, each of the first light-emitting element, the second light-emitting element, and the third light-emitting element can be photographed stably.

  In order to achieve the above object, an optical receiver according to a second aspect of the present invention includes a first light emitting element that outputs a signal light synchronized with a signal having a predetermined frequency based on transmission information, and a signal representing the predetermined frequency. An imaging unit capable of changing a frame rate for imaging the second light emitting element that outputs a frequency light that flashes in response to the flashing light, and the predetermined frequency obtained from the blinking of the second light emitting element imaged by the imaging unit. Based on the blinking of the first light emitting element photographed at the frame rate changed by the changing means, the changing means for changing the frame rate of the photographing means so as to photograph at a frame rate of 2 times or more, And extraction means for extracting transmission information.

  According to the optical receiving apparatus of the present invention, the changing means captures the frame rate of the photographing means so that the photographing is performed at a frame rate more than twice the predetermined frequency obtained from the blinking of the second light emitting element photographed by the photographing means. And the extraction means extracts the transmission information based on the blinking of the first light emitting element imaged at the frame rate changed by the changing means, so that imaging is performed at an appropriate frame rate for extracting the transmission information. can do.

  In the optical receiver according to the present invention, the photographing unit further photographs a third light emitting element that outputs light indicating the start and end of the transmission information, and the extracting unit further includes the photographing unit. The extraction of the transmission information can be started and the extraction of the transmission information can be ended based on the blinking of the third light emitting element taken by the above. Thereby, even if the transmission information is variable, the transmission information can be extracted from the signal light in accordance with the start and end timings indicated by the light.

  In the optical receiver according to the present invention, the imaging unit outputs the first imaging unit having sensitivity to the wavelength band of the light output from the first light emitting element and the second light emitting element. A second imaging unit having sensitivity in the wavelength band of light and a third imaging unit having sensitivity in the wavelength band of light output from the third light emitting element. Good. Accordingly, when the first light emitting element, the second light emitting element, and the third light emitting element are provided on the transmission side, for example, light output from the first light emitting element, second light emission By making the wavelength bands of the light output from the element and the light output from the third light emitting element different from each other, the first light emitting element, the second light emitting element, and the third light emitting element can be stably provided. Each of the elements can be photographed.

  In order to achieve the above object, an optical communication apparatus according to a third invention includes the optical transmission apparatus according to the first invention and the optical reception apparatus according to the second invention. Thereby, the first driving means of the optical transmission device outputs the signal light from the first light emitting element by driving the first light emitting element to blink in synchronization with a signal of a predetermined frequency based on the transmission information, The second driving unit of the optical transmission device outputs the frequency light from the second light emitting element by blinking and driving the second light emitting element in accordance with a signal representing a predetermined frequency, and the changing unit of the optical receiving device However, the frame rate of the imaging unit is changed so that the frame rate is twice or more the predetermined frequency obtained from the blinking of the second light emitting element taken by the imaging unit, and the extraction unit of the optical receiver is changed. Since the transmission information is extracted on the basis of the blinking of the first light emitting element imaged at the frame rate changed by the means, it is possible to image at an appropriate frame rate for extracting the transmission information.

  As described above, according to the present invention, it is possible to obtain an effect that imaging can be performed at an appropriate frame rate for extracting transmission information.

  Embodiments of an optical communication apparatus according to the present invention will be described below in detail with reference to the drawings. In the present embodiment, an example will be described in which the present invention is applied to an optical communication device that performs optical communication between the host vehicle and a surrounding vehicle that travels in front of and behind the host vehicle.

  As shown in FIG. 1, an optical communication device 10 according to an embodiment of the present invention includes an optical transmission device 12 that transmits signal light, and an optical reception device 14 that receives transmitted signal light. It is mounted on (the own vehicle 70 and the surrounding vehicle 72).

As shown in FIG. 2, the optical transmission device 12 drives each of the LEDs based on the drive signal and a signal generation device 16 that generates a drive signal for driving the light emitting element, for example, a light emitting diode (LED) to blink. Drive circuit 18a, 18b, 18c, signal length information transmission LED 20, frequency information transmission LED 22, transmission information transmission LEDs 24 _{1 to} 24 _n , and input / output interface 26.

The drive circuit 18 a is connected to the signal length information transmission LED 20, and drives the signal length information transmission LED 20 based on the drive signal input from the signal generation device 16. The drive circuit 18 b is connected to the frequency information transmission LED 22, and drives the frequency information transmission LED 22 based on the drive signal input from the signal generation device 16. Drive circuit 18c is connected to each of the LED 24 ₁ to 24 _n for transmitting the transmission information, based on the drive signal inputted from the signal generator 16 to drive each of the LED 24 ₁ to 24 _n for transmission transmitted information .

As the signal length information transmission LED 20, the frequency information transmission LED 22, and the transmission information transmission LEDs 24 _{1 to} 24 _n , a plurality of LEDs constituting a brake lamp 30 provided at the rear of each vehicle are used. As shown in FIG. 3, each of the plurality of LEDs is classified as one for the signal length information transmission LED 20, one for the frequency information transmission LED 22, and _n for the transmission information transmission LEDs 24 _{1 to} 24 _n. Has been.

  A transmission information generating device 28 is connected to the input / output interface 26. The transmission information generation device 28 generates transmission information for transmission from the optical transmission device 12 and outputs the generated transmission information to the signal generation device 16 via the input / output interface 26.

  The signal generation device 16 is a ROM 16a as a storage medium storing a basic program such as an OS, a program that executes a signal generation processing routine that will be described in detail below, and a program that executes various processing routines. An HDD (hard disk drive) 16b, a CPU 16c that reads and executes programs from the ROM 16a and the HDD 16b, a RAM 16d that temporarily stores data, and a microcomputer that includes an I / O (input / output) port 16e, etc. . The ROM 16a, HDD 16b, CPU 16c, RAM 16d, and I / O port 16e are connected to each other via a bus 16f. A drive circuit 18a, a drive circuit 18b, and a drive circuit 18c are connected to the I / O port 16e of the signal generation device 16, and a transmission information generation device 28 is connected via an input / output interface 26. Yes.

  As shown in FIG. 4, the optical receiver 14 includes an optical communication camera 32 whose frame rate can be changed, and an image processing device 34.

  The optical communication camera 32 includes an optical system 36, an image sensor 38 having a plurality of CMOSs, and a signal processing circuit 40.

  The image sensor 38 outputs an electrical signal corresponding to the amount of light received by the optical system 36 from each CMOS. The signal processing circuit 40 generates a frame image based on an electrical signal from the image sensor 38 at a predetermined frame rate FR [frame / second], and outputs the generated frame image to thereby generate a predetermined frame rate FR [frame]. / Sec]. This frame rate can be changed by control or the like by the image processing apparatus 34 described in detail below.

  The image processing apparatus 34 is a ROM 34a as a storage medium storing a basic program such as an OS, a storage medium storing a program for executing a transmission information extraction processing routine, which will be described in detail below, a program for executing various processing routines, and the like. HDD 34b, a CPU 34c that reads and executes programs from ROM 34a and HDD 34b, a RAM 34d that temporarily stores data, a microcomputer including an I / O port 34e, and the like. The ROM 34a, HDD 34b, CPU 34c, RAM 34d, and I / O port 34e are connected to each other via a bus 34f. An output device 42 configured to include a signal processing circuit 40 and a display such as a liquid crystal is connected to the I / O port 34 e of the image processing device 34.

  Next, the operation of the optical communication apparatus 10 according to this embodiment will be described. In the present embodiment, the following description will be given by taking the surrounding vehicle 72 as a vehicle that transmits signal light and the host vehicle 70 as a vehicle that receives signal light as an example.

  First, a signal generation processing routine performed by the CPU 16c of the signal generation device 16 of the optical transmission device 12 mounted on the peripheral vehicle 72 will be described with reference to FIG. In the present embodiment, this signal generation processing routine is executed when a switch (not shown) of the optical transmission device 12 is turned on.

  First, in step 100, it is determined whether or not the signal generation device 16 has received transmission information from the transmission information generation device 28.

  If it is determined in step 100 that the transmission information is received, in the next step 102, a drive signal indicating transmission information synchronized with a predetermined frequency f [Hz] is generated. For example, in step 102, a predetermined frequency as shown in FIG. 6A is obtained by changing the phase of a signal having a predetermined frequency f [Hz] corresponding to “0” and “1” of the transmission information. A drive signal indicating transmission information synchronized with f [Hz] is generated.

In the next step 104, as shown in FIG. 6C, the drive signal indicating the signal length of the drive signal indicating the transmission information generated in step 102, that is, the start P _k and the end P of the drive signal indicating the transmission information. A drive signal indicating _s is generated.

  In the next step 106, a drive signal for blinking the frequency information transmitting LED 22 at a predetermined frequency f [Hz] as shown in FIG. 6B is generated.

  In the next step 108, the drive signal generated in step 106 is output to the drive circuit 18b. As a result, as shown in FIG. 7, the frequency information transmission LED 22 is driven to blink at the frequency f [Hz], and the frequency light of frequency f [Hz] is output from the frequency information transmission LED 22.

  In the next step 110, light for one cycle is output by determining whether or not a predetermined time, for example, 1 / f [sec] has elapsed since the drive signal was output to the drive circuit 18b in step 108. It is determined whether or not. Here, with reference to FIG. 7, in step 110, it is determined whether or not one cycle has elapsed since the output of the drive signal to the drive circuit 18 b at time A in step 108 (at this time, time B is reached). By determining, it is possible to determine whether or not one period of light is output from the frequency information transmitting LED 22.

Step 110 is repeatedly executed until it is determined that light for one cycle is output from the frequency information transmission LED 22, and when it is determined in step 110 that light for one cycle is output from the frequency information transmission LED 22. In the next step 112, the drive signal indicating the transmission information generated in step 102 is output to the transmission information transmitting LEDs 24 _{1 to} 24 _n , and the drive signal indicating the start P _k and the end P _s generated in step 104 is output. It outputs to LED20 for signal length information transmission. As a result, as shown in FIG. 7, output of signal light indicating transmission information from the transmission information transmission LEDs 24 _{1 to} 24 _n is started at time B after one cycle has elapsed from time A, and at time B, Output of light indicating start P _k and end P _s of signal light indicating transmission information is started from the LED 20 for transmitting long information.

In the next step 114, whether the drive information indicating the transmission information is output to the transmission information transmission LEDs 24 _{1 to} 24 _n and the drive signal indicating the transmission information start P _k and the end P _s to the signal length information transmission LED 20 are all output. Determine whether or not.

The process of step 114 is repeated until it is determined that all have been output. When it is determined that all have been output in step 114, the output of signals to each of the drive circuits 18a, 18b, and 18c is stopped in the next step 116. Thus, the signal light from the signal length information transmission LED 20, the frequency light from the frequency information transmission LED 22, and the light indicating the start P _k and the end P _s of the transmission information from the transmission information transmission LEDs 24 _{1 to} 24 _n Output is stopped.

By the signal generation processing described above, as shown in FIG. 7, the frequency information transmission LED 22 that has started blinking driving at time A has started to output frequency light at a predetermined frequency f [Hz] at time A. In this case, at time B after a predetermined period 1 / f [sec] from time A, signal light indicating transmission information is output from the transmission information transmission LEDs 241 to 24n, and transmission information is transmitted from the signal length information transmission LED 20. The signal light indicating the start P _k and the end P _s of the signal indicating is output. Then, the signal from the signal length information transmission LED 20 is output at time C when the drive signals indicating the transmission information and the drive signals indicating the start P _k and the end P _s described above are all output to the transmission information transmission LEDs 24 _{1 to} 24 _n. Output of light, frequency light from the frequency information transmission LED 22, and light from the transmission information transmission LEDs 24 _{1 to} 24 _n is stopped.

  Next, a transmission information extraction processing routine performed by the CPU 34c of the image processing device 34 of the light receiving device 14 mounted on the host vehicle 70 will be described with reference to FIG. In the present embodiment, this transmission information extraction processing routine is executed when a switch (not shown) of the optical receiver 14 is turned on.

First, in step 200, it is determined whether or not the frequency light from the frequency information transmission LED 22 can be extracted from the frame image captured from the optical communication camera 32. Specifically, as shown in FIG. 9, from the frame image 44 captured from the optical communication camera 32, the signal length information transmission LED 20, the frequency information transmission LED 22, and the transmission information transmission LEDs 24 _{1 to} 24 _n are transmitted. The light emission pattern image 46 formed by light is extracted, the position of the image 50 indicating the frequency light from the frequency information transmitting LED 22 is specified in the extracted light emission pattern image 46, and the position corresponds to the pixel of the image 50 whose position is specified. The CMOS of the image sensor 38, that is, the CMOS 52 that receives the frequency light from the frequency information transmission LED 22 is specified, and image processing is performed on the image data obtained from the specified CMOS 52 via the signal processing circuit 40, It is determined whether or not the frequency light from the frequency information transmitting LED 22 has been extracted.

  When it is determined in step 200 that the frequency light has been extracted, in the next step 202, image data obtained in time series from the CMOS 52 specified in step 200 at a predetermined frame rate FR (frame / second) is analyzed. Thus, one period of the frequency light of the frequency information transmission LED 22 is detected, and the blinking frequency f [Hz] of the frequency light is detected from one period of the detected frequency light.

In the next step 204, it is determined whether or not the signal P _k indicating the start of transmission information has been extracted from the frame image 44 captured from the optical communication camera 32. Specifically, as shown in FIG. 9, from the frame image 44 captured from the optical communication camera 32, the signal length information transmission LED 20, the frequency information transmission LED 22, and the transmission information transmission LEDs 24 _{1 to} 24 _n are transmitted. The light emission pattern image 46 formed by light is extracted, the position of the image 48 indicating the light from the signal length information transmission LED 20 is specified in the extracted light emission pattern image 46, and the position corresponds to the pixel of the image 48 whose position is specified. The CMOS of the image sensor 38, that is, the CMOS 54 that receives light from the signal length information transmission LED 20 is specified, and image processing is performed on the image data obtained from the specified CMOS 54 via the signal processing circuit 40, A signal P _k indicating the start of transmission information from the light from the LED 20 for signal length information transmission (in this embodiment, P _k = “1”) It is determined whether or not it has been extracted.

The process of step 204 is repeatedly executed until it is determined that extraction is possible. If it is determined that extraction is possible in step 204, the next step 206 is a frequency that is twice or more the blinking frequency f [Hz] detected in step 202. For example, a frame image is generated from an electrical signal from the image sensor 38 at a frame rate FR _s (frame / second) corresponding to the frequency 2f [Hz], and the generated frame image is output to output the frame rate FR _s (frame The signal processing circuit 40 is controlled so that shooting is performed at a rate of 1 sec. Note that the frame rate FR _s (frame / second) corresponding to the double frequency 2f [Hz] means that the frame rate FR _s (frame / second) becomes 2f (frame / second), for example.

In the next step 208, the light emission pattern image 46 is extracted from the frame image output at the frame rate FR _s (frames / second) from the signal processing circuit 40 controlled in step 206, and transmission information transmission is performed from the extracted light emission pattern 46. A light emission pattern image 56 formed by signal light from the trusted LEDs 24 _{1 to} 24 _n is further extracted, and transmission information is extracted from the light emission pattern image 56 by analyzing the extracted light emission pattern image 56.

  In the next step 210, the transmission information extracted in step 208 is output to the output device 42. Thereby, the transmission information is displayed on the display of the output device 42.

In the next step 212, it is determined whether or not the signal P _s indicating the end of transmission information can be extracted from the light from the signal length information transmission LED 20 from the frame image captured from the optical communication camera 32. Specifically, as shown in FIG. 9, from the frame image 44 captured from the optical communication camera 32, the signal length information transmission LED 20, the frequency information transmission LED 22, and the transmission information transmission LEDs 24 _{1 to} 24 _n are transmitted. The light emission pattern image 46 formed by light is extracted, the position of the image 48 indicating the light from the signal length information transmission LED 20 is specified in the extracted light emission pattern image 46, and the position corresponds to the pixel of the image 48 whose position is specified. The CMOS of the image sensor 38, that is, the CMOS 54 that receives light from the signal length information transmission LED 20 is specified, and image processing is performed on the image data obtained from the specified CMOS 54 via the signal processing circuit 40, A signal P _s indicating the end of transmission information from the signal light from the signal length information transmission LED 20 (in this embodiment, P _s = 1) )) Is extracted.

  The processing of step 208 to step 212 is repeatedly executed until it is determined that the image has been extracted. If it is determined that the image has been extracted in step 212, the next step 214 is the image sensor 38 at the original frame rate FR (frame / second). By generating a frame image from the electrical signal from and outputting the generated frame image, the signal processing circuit 40 is controlled to perform shooting at the original frame rate FR (frame / second), and the process returns to step 200. .

As described above, according to the optical communication device 10 according to the present embodiment, the drive circuit 18c of the optical transmission device 12 synchronizes with the signal of the predetermined frequency f [Hz] based on the transmission information. Each of the transmission LEDs 24 _{1 to} 24 _n is driven to blink, whereby signal light is output from each of the transmission information transmission LEDs 24 _{1 to} 24 _n , and the drive circuit 18 b of the optical transmission device 12 has a predetermined frequency f [Hz]. The frequency information transmission LED 22 is driven to blink in response to a signal representing the frequency information, and the frequency information transmission LED 22 outputs frequency light, and the image processing device 34 of the optical receiver 14 is captured by the optical communication camera 32. for optical communication to capture at least twice the frame rate FR _s [frames / sec] of a predetermined frequency f obtained from flashing frequency information transmission LED 22 [Hz] Change the frame rate of the camera 32, the image processing apparatus of the optical receiver 14 34, the frame rate is changed by the image processing apparatus 34 FR _s [frames / sec] in the captured transmitted information transmission LED 24 ₁ to 24 _n Since the transmission information is extracted based on each blinking, it is possible to capture an image at an appropriate frame rate for extracting the transmission information.

  For example, according to the optical communication apparatus 10 according to the present embodiment, as shown in FIG. 10, the transmission information is alternately transmitted from the surrounding vehicles 80, 82, and 84 at frequencies f1 [Hz], f2 [Hz], and f3 [ Even when transmitted at a frequency of [Hz], a frame rate suitable for shooting at the respective frequencies f1 [Hz], f2 [Hz], and f3 [Hz], for example, satisfies the sampling theorem (f1 × 2) [Frames / second], (f2 × 2) [frames / second], (f3 × 2) [frames / second], images of each of the surrounding vehicles 80, 82, 84, and the results of the imaging By outputting the obtained frame image, the surrounding vehicles 80, 82, and 84 are photographed at the corresponding frame rates, and the transmission information is extracted from the output frame image, so the transmission information is extracted. It can be imaged at the appropriate frame rate because.

  Further, according to the optical communication device 10 according to the present embodiment, the transmission side outputs light indicating the start and end of transmission information, the reception side receives this light, and the transmission information is based on the received light. Therefore, even if the transmission information is variable, the transmission information can be extracted from the signal light in accordance with the start and end timings indicated by the light.

  In the present embodiment, an example in which signal light is output and communication is performed using a light emitting diode of a brake light including a plurality of light emitting diodes provided at the rear of the vehicle has been described. Communication between the vehicle and the traffic light may be performed by outputting signal light using a light emitting diode of the traffic light.

In the present embodiment, the example in which one optical communication camera 32 is used to photograph the signal length information transmission LED 20, the frequency information transmission LED 22, and the transmission information transmission LEDs 24 _{1 to} 24 _n has been described. The wavelength band of the light output from the LED 20 for signal length information transmission, the wavelength band of the light output from the LED 22 for frequency information transmission, and the wavelength band of the light output from the LEDs 24 _{1 to} 24 _n for transmission information transmission And the optical receiver 14 outputs from the first optical communication camera having sensitivity to the wavelength band of the light output from the signal length information transmitting LED 20 and the frequency information transmitting LED 22 as photographing means. a second optical communication camera having sensitivity in a wavelength band of the light, the sensitivity in the wavelength band of the output from the transmission information transmission LED 24 ₁ to 24 _n light It may be provided with a third optical communication camera. Thus, each of the signal length information transmission LED 20, the frequency information transmission LED 22, and the transmission information transmission LEDs 24 _{1 to} 24 _n can be photographed stably.

  In the present embodiment, the number of signal length information transmission LEDs 20 and frequency information transmission LEDs 22 is one, but at least one of them may be plural.

  In the present embodiment, the image sensor 38 includes a plurality of CMOSs, but the image sensor 38 may include other image sensors such as a CCD.

It is the schematic which shows the structure of the optical communication apparatus which concerns on this Embodiment. It is a block diagram which shows the structure of the optical transmitter of the optical communication apparatus which concerns on this Embodiment. It is a figure which shows LED for signal length information transmission, LED for frequency information transmission, and LED for transmission information transmission arrange | positioned at the brake light of each vehicle which concerns on this Embodiment. It is a block diagram which shows the structure of the optical receiver of the optical communication apparatus which concerns on this Embodiment. It is a figure which shows the flowchart of the signal generation process routine which CPU of the signal generation apparatus of the optical transmission apparatus which concerns on this Embodiment performs. It is a figure which shows the various drive signals which the signal generation apparatus in the optical communication apparatus which concerns on this Embodiment produces | generates. It is a figure which shows the light from the LED for signal length information transmission which concerns on this Embodiment, the frequency light from LED for frequency information transmission, and the signal light from LED for transmission information transmission. It is a figure which shows the flowchart of the transmission information extraction process routine which CPU of the image processing apparatus of the optical receiver which concerns on this Embodiment performs. It is a figure for demonstrating the process in step 200, 204, 208, 212 of a transmission information extraction process routine. It is a figure which shows the effect of the optical communication apparatus which concerns on this Embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Optical communication apparatus 12 Optical transmission apparatus 14 Optical reception apparatus 16 Signal generation apparatus 20 LED for signal length information transmission
22 LED for frequency information transmission
24 Transmitting information transmission LED
32 Optical Communication Camera 34 Image Processing Device 36 Optical System 38 Image Sensor 40 Signal Processing Circuit

Claims (8)

First driving means for outputting signal light from the first light emitting element by driving the first light emitting element to blink in synchronization with a signal of a predetermined frequency based on transmission information;
Second driving means for outputting frequency light from the second light emitting element by blinking driving the second light emitting element in accordance with the signal representing the predetermined frequency;
An optical transmission device comprising:   Third driving means for causing the third light emitting element to output light indicating the start and end of transmission information represented by the signal light output from the first light emitting element by driving the third light emitting element to blink. The optical transmission device according to claim 1, further comprising:   As at least one of the first light-emitting element, the second light-emitting element, and the third light-emitting element, a light-emitting diode of a brake lamp including a plurality of light-emitting diodes provided at the rear of the vehicle, or a plurality of light-emitting diodes 3. The optical transmission device according to claim 1, wherein the light emitting diode of a traffic light equipped with the light emitting diode is used.   The wavelength bands of the light output from the first light emitting element, the light output from the second light emitting element, and the light output from the third light emitting element are different from each other. Item 4. The optical transmitter according to any one of Items 3 to 3. A frame for photographing a first light emitting element that outputs signal light synchronized with a signal of a predetermined frequency based on transmission information, and a second light emitting element that outputs frequency light that flashes according to the signal indicating the predetermined frequency. Photography means that can change the rate,
Changing means for changing the frame rate of the photographing means so as to photograph at a frame rate twice or more of the predetermined frequency obtained from blinking of the second light emitting element photographed by the photographing means;
Extracting means for extracting the transmission information based on the blinking of the first light emitting element that was shot at the frame rate changed by the changing means;
An optical receiver comprising: The imaging means further images a third light emitting element that outputs light indicating the start and end of the transmission information,
The light according to claim 5, wherein the extraction unit further starts extracting the transmission information based on the blinking of the third light emitting element imaged by the imaging unit, and ends the extraction of the transmission information. Receiver device.   The imaging unit includes a first imaging unit having sensitivity in a wavelength band of light output from the first light emitting element, and a second having sensitivity in a wavelength band of light output from the second light emitting element. The optical receiver according to claim 5, further comprising: an imaging unit configured to include a third imaging unit having sensitivity to a wavelength band of light output from the third light emitting element. An optical transmitter according to any one of claims 1 to 4,
An optical receiver according to any one of claims 5 to 7,
An optical communication device including:

Images