JP2000125176A - Remote image pickup device and image pickup transmitter - Google Patents

Abstract

PROBLEM TO BE SOLVED: To unnecessitate a power source wire and a signal wire by switching power generated by performing photoelectric conversion of light to power of a secondary battery and supplying it to an image picking up means and a 1st optical space transmitting means. SOLUTION: A power supply controlling part 40 feeds power of a solar battery 30 to an optical space transmitter 300 and a camera part 10 in the daytime when there is much quantity of light and charges a secondary battery 35 with surplus power at the same time. Also, power is supplied from the battery 35 at the time when there is small quantity of light such as at night or cloudy weather. A back flow preventing diode 41 for the power supply controlling part 40 is also provided, its anode is connected to a positive electrode of the battery 30, and current back flow from the secondary battery 35 to the solar battery 30 is prevented at night when the voltage of the battery 30 falls below the voltage of the secondary battery 35. A charge controlling part 43 controls a charging current to the secondary battery 35 in accordance with charged quantity of the battery 35 and prevents the battery 35 from being overcharged. Also, a voltage controlling part 42 feeds voltage supplied by the batteries 30 and 35 to the camera part 10 and the optical space transmitter 300 as prescribed voltage.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a remote imaging apparatus and an imaging transmission apparatus, and is suitably applied to, for example, a remote imaging apparatus and an imaging transmission apparatus in which imaging means is installed at a remote place.

[0002]

2. Description of the Related Art Conventionally, there is a fixed-point observation camera which is installed at a predetermined photographing point and images a predetermined object to be imaged such as a road or a mountain and sends out a video signal. In such a fixed-point observation camera, it is necessary to lay cables such as a power supply line for supplying power to the fixed-point observation camera and a signal line for transmitting a video signal.

[0003]

However, such a fixed-point observation camera is often installed in a remote place such as the roof of a building or the top of a mountain. There is a problem that the laying will affect the landscape.

In order to solve such a problem, it is conceivable to transmit a video signal via a radio wave. However, in order to transmit a video signal having a practical resolution, several M
A wide band of Hz is required, which is not practical from the viewpoint of radio wave allocation. Even if radio waves can be allocated, there are problems such as overreach and interference that radio waves can reach outside the expected radio wave coverage, and a large transmitting antenna is required to transmit such wideband radio waves. And still have the problem of high power consumption.

The present invention has been made in view of the above points, and has as its object to propose a remote imaging apparatus and an imaging transmission apparatus which have a simple configuration and do not use a power line and a signal line.

[0006]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, according to the present invention, an image pickup means for picking up an image of a predetermined image pickup object to generate a video signal, and transmitting the video signal via a first light beam. A first spatial light transmission means, and a second spatial light transmission, which is installed at a predetermined distance from the first spatial light transmission means, receives the first light beam, demodulates a video signal, and outputs the demodulated video signal to the outside. Means, photovoltaic power generation means for photoelectrically converting light to generate power, a secondary battery storing the power generated by the photovoltaic power generation means, and power and secondary battery generated by the photovoltaic power generation means And a power supply control means for switching between the power stored in the power supply and the power supply means for supplying the power to the imaging means and the first optical space transmission means.

[0007] Further, a photographing control signal for controlling the photographing operation of the photographing means supplied from the outside is transmitted from the first space optical transmission device to the first space optical transmission device via the second light beam. The first optical space transmission means receives the second light beam, demodulates the photographing control signal, and outputs it to the imaging means.

The video signal is transmitted from the first optical space transmission means to the first
And a photographing control signal for controlling the photographing operation of the image pickup means from the second light space transmission means via the second light beam to the first space light transmission means.
And the power supply from the photovoltaic power generation means or the secondary battery to the image pickup means and the first optical space transmission means. There is no need to lay cables.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below in detail with reference to the drawings.

(1) Configuration of Device (1-1) Overall Configuration of Remote Imaging Device In FIG. 1, reference numeral 1 denotes a remote imaging device as a whole, and a control unit 100 and a control side light as a second optical space transmission unit. The control-side device 2 including the spatial transmission device 200, a camera unit 10 as an imaging unit, a turntable 15 on which the camera unit 10 is mounted and controls a shooting direction of the camera unit 10, and a power supply unit 20
And a remote device 3 including a remote optical space transmission device 300 as first optical space transmission means.

The remote device 3 is installed at a remote place such as a mountaintop, for example, and the camera unit 10, the turntable 15, and the remote optical space transmission device 300 operate with power supplied from the power supply unit 20. The power supply unit 20 includes a solar cell 30 as a photovoltaic power generation unit, a secondary battery 35, and a power supply control unit 40 as a power supply unit. , And power is supplied to the camera unit 10, the turntable 15, and the remote-side optical space transmission device 300 from either the solar battery 30 or the secondary battery 35.

On the other hand, the control-side device 2 is installed, for example, in an urban area, and the remote-side optical space transmission device 300 and the control-side optical space transmission device 200 are installed facing each other at a predetermined distance.

The control unit 100 controls a photographing operation of the camera unit 10 according to an operation input by an operator.
101 and a photographing direction control signal S102 for controlling the photographing direction of the camera unit 10 are generated.
Output to 0. The control-side optical spatial transmission device 200 transmits the imaging control signal S101 and the imaging direction control signal S102 to the remote optical spatial transmission device 300 via the light beam L2.

The remote-side optical space transmission apparatus 300 receives the light beam L2, demodulates the photographing control signal S101 and the photographing direction control signal S102, and outputs them to the camera unit 10 and the turntable 15, respectively. The camera unit 10 has a shooting control signal S1
The photographing operation is performed in response to 01, and a video signal S10 is output. The turntable 15 rotates up and down and left and right according to the shooting direction control signal S102, and controls the shooting direction of the camera unit 10 to the direction specified by the operator.

The remote optical transmission apparatus 300 transmits the video signal S10 output from the camera unit 10 to the control optical transmission apparatus 200 via the light beam L1. The control-side optical free space transmission device 200 receives the light beam L1, demodulates the video signal S10, and outputs it to the outside.

Thus, the control device 2 controls the camera unit 10 of the remote device 3 installed at a remote place via the light beam L2, and receives a video signal via the light beam L1. .

(1-2) Configuration of Power Supply Unit FIG. 2 shows the power supply unit 20, and includes a solar cell 30 and a secondary battery 3.
5 is connected to the power control unit 40.

The solar cell 30 is made of single-crystal Si (silicon).
A photovoltaic power is generated by forming a pn bond by diffusing p-type impurities into an n-type flat plate crystal to form a pn bond, and using the p-type surface as a light receiving surface to receive light. I do. Each cell constituting the solar cell 30 has an extraction voltage of 0.6 [V], an extraction current density of 29 [mA / cm ² ], and an efficiency of
Works at 12.5 [%]. Since the solar cell has a low electromotive voltage per cell, a desired output voltage is obtained by connecting a plurality of cells in series.

The secondary battery 35 comprises a plurality of lead storage batteries,
A desired output voltage is obtained by connecting the lead storage batteries in series, and a desired power supply capacity is obtained by connecting these lead storage batteries in parallel.

The power supply control unit 40 supplies power obtained from the solar cell 30 to the optical space transmission device 100 and the camera unit 10 according to the output voltage of the solar cell 30 when the amount of light is large, such as during daytime. The secondary battery 35 is also charged, and when the amount of light is small, such as at night or in cloudy weather, the power charged in the secondary battery 30 according to the output voltage of the solar battery 30 is transmitted to the optical space transmission device 100 and the camera unit 10. Supply for Backflow prevention diode 4 included in power supply control unit 40
In a state 1 in which the anode is connected to the positive electrode of the solar cell 30 and the cathode is connected to the secondary battery 35, and the generated voltage of the solar cell 30 is lower than the terminal voltage of the secondary battery 35 at night or the like, From the secondary battery 35 to the solar battery 3
The current is prevented from flowing back to 0. The charging control unit 43 prevents overcharge of the secondary battery 35 by controlling the charging current supplied to the secondary battery 35 according to the charging capacity of the secondary battery 35. The voltage control unit 42 converts the voltage supplied from the solar battery 30 and the secondary battery 35 into a predetermined voltage and supplies the predetermined voltage to the camera unit 10 and the optical wireless transmission device 100.

(1-3) Configuration of Control-Side Optical Space Transmission Apparatus FIG. 3 shows a control-side optical space transmission apparatus 200 as a whole. ) The S / N ratio deterioration warning signal S86 supplied from 86, the photographing control signal S101 and the photographing direction control signal S102 supplied from the control unit 100 (FIG. 1) are frequency-multiplexed by the modulating unit 81, and then modulated. S81 is generated and supplied to the laser diode drive circuit 82. S / N ratio deterioration warning signal S86
Is the S / N ratio of the light beam L1 transmitted from the remote-side optical space transmission apparatus 300 in the control-side optical space transmission apparatus 200.
Output when the ratio (Signal to Noise Ratio) is less than a predetermined threshold.

The laser diode drive circuit 82 generates a drive current S82 according to the modulation signal S81 and drives the laser diode 61, so that the laser diode 61 emits laser light modulated according to the modulation signal S81. The light beam L2 is emitted.

The control-side optical free-space transmission device 200 converts the light beam L2 into parallel light by the lens 64 and makes it incident on the prism 50. The prism 50 includes a first right-angle prism 50A and a second right-angle prism 50B having the same size, and a third right-angle prism 50C.
A, the slope of the second right-angle prism 50B,
Are formed so that the right-angle surfaces of the right-angle prism 50C have the same shape. The prism 50 is formed by bonding the slope of the first right-angle prism 50A and the slope of the second right-angle prism 50B to the respective right-angle surfaces of the third right-angle prism 50C. Polarizing beam splitter M1 on the bonding surface of right angle prism 50C
And a beam splitter M2 is formed on the bonding surface between the second right-angle prism 50B and the third right-angle prism 50C. The polarizing beam splitter M1 reflects or transmits the incident light beam at right angles according to the plane of polarization thereof. Further, the beam splitter M2 reflects a part of the incident light beam at a right angle, and transmits a part of the incident light beam in a straight line.

The polarizing beam splitter M1 of the prism 50
Reflects the light beam L2 at a right angle and exits to the lens 67 via the servo mirror 90. The lenses 67 and 68 expand the light beam diameter of the light beam L2 and
Emitted at 00 (FIG. 1). Thus, at the time of transmission, the control-side optical space transmission device 200 controls the camera unit 10 to control the imaging control signal S101, controls the turntable 15 to control the imaging direction control signal S102, and transmits the light beam L1 in the control-side optical space transmission device 200. S / N ratio signal S86 indicating / N ratio
Through the light beam L2 to the remote-side optical space transmission device 300
Send to

At this time, the CPU 86 performs an optical axis correction process, which will be described later, so that the optical axis of the light beam L1 and the light beam L2
And the light beam L2 is made to coincide with the remote-side optical space transmission device.

On the other hand, at the time of reception, the control-side optical space transmission apparatus 200 receives the light beam L1 emitted from the remote-side optical space transmission apparatus 300, and reduces the beam diameter of the received light beam L1 by the lenses 68 and 67. And the servo mirror 90
Through the prism 50. The polarization beam splitter M1 of the prism 50 transmits the light beam L1 straight and guides it to the beam splitter M2. Beam splitter M2
Reflects a part of the light beam L1 at a right angle, condenses it on the position detecting element 63 via the lens 66, and
The remainder of 1 is transmitted straight through and condensed on a light receiving element 62 formed of a photodiode via a lens 65.

The light receiving element 62 photoelectrically converts the light beam L1 condensed by the lens 65 to generate an output signal S62 and outputs the output signal S62 to a PD (Photo Diode) light receiving circuit 84. S62 is subjected to current-voltage conversion and output to the demodulation unit 83. The demodulation unit 83 demodulates the output signal S62 to generate a video signal S10,
6 and sent out. The CPU 86 outputs the video signal S10
Is calculated and sent to the modulation section 81 as an S / N ratio signal S86.

Thus, at the time of reception, the control-side optical space transmission apparatus 200 receives the video signal S10 from the remote-side optical space transmission apparatus 300 via the light beam L1.

(1-4) Configuration of Remote-Side Optical Space Transmission Apparatus In FIG. 4, in which parts common to FIG. 3 are assigned the same reference numerals, reference numeral 300 denotes a remote-side optical space transmission apparatus. At the time of reception, the transmission apparatus 300 receives the light beam L2 emitted from the control-side optical space transmission apparatus 200,
The luminous flux diameter of the received light beam L2 is determined by the lenses 68 and 6
The light is reduced at 7 and enters the prism 50 via the servo mirror 90. Polarizing beam splitter M1 of prism 50
Is a beam splitter M2 that transmits the light beam L2 in a straight line.
Lead to. The beam splitter M2 reflects a part of the light beam L2 at a right angle, condenses it on the position detecting element 63 via the lens 66, and transmits the rest of the light beam L2 straight through, and receives the light from the photodiode via the lens 65. Element 62
Focus on

The light receiving element 62 photoelectrically converts the light beam L2 condensed by the lens 65 to generate an output signal S62, and outputs the output signal S62 to a PD (Photo Diode) light receiving circuit 74. S62 is subjected to current-voltage conversion and output to the demodulation unit 73. The demodulation unit 73 demodulates the output signal S62 and outputs the S / N ratio deterioration warning signal S86, the photographing control signal S101 and the photographing direction control signal S102 to the CPU 75, the camera unit 10 (FIG. 1), and the turntable 15 respectively.
(FIG. 1).

The turntable 15 receives a photographing direction control signal S102.
To rotate the camera unit 10 placed on the rotary table 15 in the vertical and horizontal directions. The camera unit 10 performs a shooting operation in accordance with the shooting control signal S101, generates a video signal S10, and outputs the video signal S10 to the remote-side optical space transmission device 300.

On the other hand, at the time of transmission, the remote-side optical free space transmission apparatus 300 transmits the video signal S1 supplied from the camera unit 10.
0 is input to the modulation unit 71. The modulating section 71 outputs the video signal S
An operation state signal S76 indicating the operation state of the remote apparatus 3 supplied from the CPU 10 and the CPU 76 is frequency-multiplexed as shown in FIG. 5 and then modulated to generate a modulation signal S71, which is supplied to the laser diode drive circuit 72. .

The laser diode drive circuit 72 generates a drive current S72 in accordance with the modulation signal S71 and drives the laser diode 61, so that the laser diode 61 emits laser light modulated in accordance with the modulation signal S71. The beam L1 is emitted. At this time, the CPU 76 executes an oscillation wavelength control process, which will be described later, generates a wavelength control signal S77 based on the S / N ratio deterioration warning signal S86 and outputs the wavelength control signal S77 to the laser diode drive circuit 72, thereby changing the oscillation wavelength of the light beam L1. Control to avoid a decrease in the S / N ratio of the light beam L1 due to absorption in the atmosphere.

The remote-side optical free space transmission apparatus 300 converts the light beam L 1 into parallel light by the lens 64 and enters the prism 50. The polarization beam splitter M1 of the prism 50 reflects the light beam L1 at a right angle, and emits the light beam L1 to the lens 67 via the servo mirror 90. The lenses 67 and 68 expand the light beam diameter of the light beam L1 to increase the control side optical space transmission apparatus 200.
Out. Thus, at the time of transmission, the remote-side optical free space transmission apparatus 300 transmits the video signal S supplied from the camera unit 10.
10 and an operation state signal S76 supplied from the CPU 76
Is transmitted to the control-side transmission device 300 via the light beam L1.

At this time, the CPU 86 performs an optical axis correction process, which will be described later, so that the optical axis of the light beam L1 and the light beam L2
And the light beam L1 is made to coincide with the control-side optical space transmission apparatus.

(2) Optical Axis Correction Processing The control-side optical spatial transmission apparatus 200 transmits the optical axis of the light beam L2 to the remote optical spatial transmission by matching the optical axis of the light beam L1 with the optical axis of the light beam L2. An optical axis correction process that matches the apparatus 300 is performed. In FIG. 3, the position detecting element 63
Receives the light beam L1 condensed by the lens 66, and receives the light beam L1 on the light receiving surface of the position detecting element 63.
A position signal S63 having a current level corresponding to the position of the intensity center of gravity of No. 1 is generated, and a PSD (Position Sensitive Device) is generated.
) Send the light to the light receiving circuit 85. The PSD light receiving circuit 85
The position signal S 63 is subjected to current-voltage conversion and sent to the CPU 86.

The CPU 86 calculates the focal position of the light beam L1 on the lecture surface of the position detecting element 63 using the position signal S63, and sets the servo mirror 90 so that the predetermined focal reference position and the focal position of the light beam L1 coincide. The optical axis of the light beam L1 and the light beam L2
And the optical axis of the light beam L2 is matched with the remote-side optical space transmission apparatus 300.

The remote-side optical free space transmission apparatus 300 also performs the same optical axis correction processing so that the optical axis of the light beam L1 matches the control-side optical free-space transmission apparatus 200.

(3) Oscillation Wavelength Control Processing In optical space transmission for long-distance signal transmission, the light beam is attenuated by the interaction between the absorption of atmospheric spectrum and the fluctuation of the oscillation spectrum of the laser diode, which is the light source of the light beam. However, this is known to affect the C / N ratio (carrier power to noise power ratio) during signal transmission. As shown in FIG. 6, a large number of wavelength absorption spectra of the atmosphere can be confirmed in the 780 [nm] to 830 [nm] band, which is often used as a laser oscillation wavelength in optical space transmission. FIG. 6 shows the vicinity of 770.0 [nm] to 841.6 [nm] in the wavelength absorption spectrum of the atmosphere.

Here, for example, a laser diode oscillating at a single wavelength such as a single longitudinal mode is used as a laser light source, and the oscillation wavelength of the laser diode is changed to the wavelength of the atmosphere by an oscillation wavelength shift caused by temperature characteristics and the like. When the absorption wavelength coincides with the absorption wavelength of the absorption spectrum (FIG. 6), the laser power is attenuated by the absorption wavelength and the C / N ratio is degraded. It is confirmed that a sharp increase in noise far exceeding C / N ratio deterioration due to power attenuation occurs with good reproducibility. Such noise is referred to herein as wavelength absorption noise.
This wavelength absorption noise is caused by the wavelength shift due to the temperature characteristics of the laser diode, etc., which normally has been transmitted without any problem, the noise gradually increases due to the temperature change. After continuing, it shows the property of recovering gradually. Since this wavelength absorption noise is due to the absorption in the atmosphere, the influence thereof has a property of becoming exponentially larger with respect to the transmission distance.

The generation mechanism of the wavelength absorption noise can be described with reference to FIG. That is, when the laser oscillation wavelength overlaps the shoulder of the atmospheric wavelength absorption spectrum, the fluctuation in the laser wavelength direction is converted into the fluctuation in the intensity direction, and the fluctuation in the intensity direction in the receiving device is reduced. It is thought that it will be observed as intensity noise. That is, even if the laser oscillation wavelength is in the absorption wavelength band of the atmosphere, the C / N ratio of the signal transmitted by the laser light of the wavelength is slightly deteriorated unless the wavelength of the laser light changes. However, if the wavelength of the laser light fluctuates due to a temperature change, aging, etc. of the laser diode, the wavelength fluctuation (ie, frequency fluctuation)
Is converted to amplitude fluctuation.

In order to avoid this problem, the oscillation wavelength of the laser and the absorption spectrum of the atmosphere need not be matched. That is, when the C / N ratio starts to deteriorate due to the laser oscillation wavelength approaching the absorption spectrum, the laser oscillation wavelength is controlled so as to avoid the absorption spectrum.
Actually, the S / N ratio (signal-to-noise ratio) deteriorates according to the deterioration of the C / N ratio. Therefore, according to the information of the S / N ratio at the receiving side, the laser is controlled to avoid the absorption spectrum at the transmitting side. Control the oscillation wavelength.

That is, in FIG. 3, when the S / N ratio of the light beam L1 in the control-side optical free space transmission apparatus 200 becomes smaller than a predetermined threshold, the CPU 86 issues an S / N ratio deterioration warning signal indicating the deterioration of the S / N ratio. S86 is output. Then, the control-side optical free space transmission apparatus 200 outputs the S / N ratio deterioration warning signal S86.
Is transmitted to the remote-side optical space transmission device 300 via the light beam L2.

In FIG. 4, the remote-side optical space transmission device 30
0 executes the oscillation wavelength control process shown in FIG. 7 based on the S / N ratio deterioration warning signal S86.
1 so that the wavelength of 1 does not coincide with the absorption spectrum of the atmosphere.
The D drive circuit 72 is controlled. In FIG. 7, the CPU 76
Starts the process in step SP1, and determines in step SP2 whether the demodulation unit 73 outputs the S / N ratio deterioration warning signal S86. If a negative result is obtained in step SP2, this means that the S / N ratio deterioration warning signal S86 has not been output, that is, the S / N ratio of the light beam L1 in the control-side optical space transmission apparatus 200 has reached a predetermined threshold. This means that the processing returns to step SP2.

On the other hand, if a positive result is obtained in step SP2, this indicates that the S / N ratio deterioration warning signal S86 has been obtained.
Is output, that is, the S / N ratio of the light beam L1 in the control-side optical free space transmission apparatus 200 is less than a predetermined threshold, and the process proceeds to step SP3.

In step SP3, the CPU 76 generates a wavelength control signal S77 for changing the oscillation wavelength of the laser diode 61 based on the temperature change and the current change of the laser diode 61, and sends this to the laser diode 61.
Output to The laser diode 61 receives the wavelength control signal S
The oscillation wavelength changes according to 77. Then, the CPU 76 returns to step SP2 again, and repeatedly determines whether or not the S / N ratio deterioration warning signal S86 is output from the demodulation unit 73.

Thus, C of the remote-side optical space transmission apparatus 300
The PU 76 changes the wavelength of the light beam L1 when the S / N ratio of the light beam L1 in the control-side optical free space transmission apparatus 200 becomes less than a predetermined threshold, so that the wavelength of the light beam L1 is absorbed by the atmosphere. Control so that it does not match the spectrum.

The wavelength of light and the effect of the wavelength of light on the eye will be described with reference to FIG. FIG. 9 shows the relationship between the transmittance of light entering from the cornea to the fundus and the absorptivity at the fundus, both of which show 100% on the cornea.
And FIG. 9 shows that ultraviolet rays and far infrared rays having a wavelength longer than 1500 [nm] hardly enter the eye.

On the other hand, about 400 [nm]
The cornea and the crystalline lens are transparent to 1200 [nm], and the light intensity per unit area at the fundus becomes extremely large due to the light condensing action of the crystalline lens. In addition, the absorptivity of light at the fundus is large for blue light, but decreases as the wavelength increases,
Even if light reaches the fundus, the absolute absorption of energy is extremely small.

For this reason, the use of laser light having a wavelength of about 1.4 [μm] or more in terms of environmental hygiene for the eyes can substantially eliminate the effect on human eyes. Therefore, in the remote photographing apparatus 1 of the present invention, about 1.4
By using the laser diode 19 that oscillates a laser beam having a wavelength of [μm] or more, the influence on the human eye is reduced and the safety is improved.

(4) Operation and Effect In the above configuration, the operator of the remote imaging device 1 operates the control unit 100 of the control device 2 and operates the camera unit 10 and the turntable 15 of the remote device 3. Enter instructions.

The transmitting side optical free space transmission apparatus 200 responds to an S / N ratio deterioration warning signal S86 indicating the deterioration of the S / N ratio of the light beam L1 in the transmitting side optical free space transmitting apparatus 200 and an operation instruction input by the operator. The generated photographing control signal S101 for controlling the photographing operation of the camera unit 10 and the photographing direction control signal S102 for controlling the photographing direction of the camera unit 10 are converted into light beam L.
2 to the remote-side optical space transmission device 300 of the remote-side device 3.

The remote-side optical space transmission apparatus 300 receives the light beam L2 and demodulates the S / N ratio deterioration warning signal S86, the photographing control signal S101, and the photographing direction control signal S102,
Each is output to the CPU 76, the camera unit 10, and the turntable 15.

The camera unit 10 executes a photographing operation in response to a photographing control signal S101 and outputs a video signal S10, and the turntable 15 rotates up and down and left and right in response to a photographing direction control signal S102. The direction is controlled to the direction specified by the operator. And the remote side optical space transmission device 300
Transmits the video signal S10 to the control-side optical free space transmission device 200 via the light beam L1. Control-side optical space transmission device 2
00 receives the light beam L1, demodulates the video signal S10, and outputs it to the outside.

Here, the camera unit 10, the turntable 15, and the remote-side optical space transmission device 300 are supplied with power from the solar battery 30 during the daytime, and when the sun is hidden at night or in cloudy weather. Secondary battery 3 charged by solar battery 30
5 is supplied with electric power to perform the operation.

At this time, by controlling the wavelength of the light beam L1 in accordance with the S / N ratio deterioration warning signal S86, the CPU 76 of the remote-side optical free space transmission apparatus 300 changes the wavelength of the light beam L1 to the absorption spectrum of the atmosphere. Avoid the attenuation of the light beam L1 that occurs when they match.

Thus, the control device 2 controls the camera unit 10 of the remote device 3 installed at a remote place via the light beam L2, and receives a video signal via the light beam L1.

According to the above configuration, the remote imaging device 1 is composed of the control device 2 and the remote device 3, and the camera section 10 and the turntable 15 of the remote device 3 are transmitted from the control device 2 to the light beam L 2. , And the video signal S10 generated by the camera unit 10 is transmitted from the remote device 3 to the control device 2 via the light beam L1. And secondary battery 3
5 is provided, and power is supplied from the power supply unit 20 to the camera unit 10, the turntable 15, and the remote-side optical space transmission device.
There is no need to lay cables for the power line and the signal line between the remote device 3 and the remote device 3.

Further, an S / N ratio deterioration warning signal S86 indicating the deterioration of the S / N ratio of the light beam L1 in the control-side optical free space transmission device 200 included in the control-side device 2 is sent from the remote-side device 3 to the control-side device 2. The transmission is performed via the light beam L1.
By controlling the oscillation wavelength of the light beam L1 according to the N-ratio deterioration warning signal S86, the wavelength of the light beam L1 is controlled by controlling the wavelength of the light beam L1 according to the notification signal S86. It is possible to avoid the attenuation of the light beam L1 that occurs when the spectrum coincides with the spectrum.

(5) Other Embodiments In the above embodiment, the single crystal Si was used as the material of the solar cell 30, but the present invention is not limited to this.
Various other solar cell materials such as amorphous Si may be used.

In the above-described embodiment, a lead battery is used as the secondary battery 35. However, the present invention is not limited to this, and various other secondary batteries such as a nickel-cadmium battery may be used. .

Further, in the above-described embodiment, the video signal S10 and the operation state signal S76 are frequency-multiplexed in the remote-side optical space transmission apparatus 300, but the present invention is not limited to this, and various other methods such as time division multiplexing may be used. Any suitable signal multiplexing method may be used.

[0063]

As described above, according to the present invention, the image signal and the photographing control signal are transmitted via the light beam, and the image pickup means and the first signal are transmitted from the photovoltaic power generation means or the secondary battery. By supplying power to the optical space transmission means, it is possible to easily realize a remote imaging device and an imaging transmission device with a simple configuration that do not use a power line and a signal line.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating a configuration of a remote imaging device.

FIG. 2 is a block diagram illustrating a configuration of a power supply unit.

FIG. 3 is a block diagram illustrating a configuration of a control-side optical section transmission device.

FIG. 4 is a block diagram showing a configuration of a remote optical section transmission device.

FIG. 5 is a graph showing frequency multiplexing.

FIG. 6 is a graph showing an absorption spectrum by the atmosphere.

FIG. 7 is a schematic diagram for explaining an increase in noise due to absorption in the atmosphere.

FIG. 8 is a flowchart illustrating an oscillation wavelength control process.

FIG. 9 is a graph showing light transmittance in an eye and light absorption in a fundus.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Remote imaging device, 2 ... Control side device, 3 ... Remote side device, 10 ... Camera part, 15 ... Turntable, 20 ... Power supply part, 30 ... Solar cell, 35 ... Secondary Battery, 40 ...
Power control unit, 100: control unit, 200: control side optical space transmission device, 300: remote side optical space transmission device.

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Takashi Otobe 6-35 Kita-Shinagawa, Shinagawa-ku, Tokyo F-term within Sony Corporation (reference) 5C022 AA00 AA01 AB40 AB65 AB68 AC42 AC69 5C054 AA02 BA01 BA03 BA06 CC02 CF05 CG05 CH02 DA07 EA01 EA03 EA05 HA37

Claims (9)

[Claims] 1. A remote imaging apparatus for imaging a predetermined imaging target to generate a video signal and transmitting the video signal via a light beam, wherein the imaging includes imaging the predetermined imaging target to generate a video signal. Means, first space optical transmission means for transmitting the video signal via a first light beam, and first light beam installed at a predetermined distance from the first space light transmission means A second optical space transmission means for receiving the image signal, demodulating the video signal, and outputting the demodulated signal to the outside; a photovoltaic power generation means for photoelectrically converting light to generate electric power; A secondary battery for storing power, a power supply for switching between the power generated by the photovoltaic power generation means and the power stored in the secondary battery and supplying the power to the imaging means and the first optical space transmission means Having control means Remote imaging device according to claim. 2. The first optical space transmission means transmits operating state information of the imaging means, the first optical space transmission means, the photovoltaic power generation means, the secondary battery, and the power supply means. 2. The remote imaging apparatus according to claim 1, wherein the video signal is multiplexed with the video signal and transmitted to the second optical space transmission unit via the first light beam. 3. The imaging means has an imaging direction control means for controlling an imaging direction, and the second optical space transmission means transmits an imaging direction control signal input from the outside via a second light beam. The first optical space transmission means receives the second light beam, demodulates the imaging direction control signal, and outputs the signal to the imaging direction control means. The remote imaging device according to claim 1, wherein: 4. The first space optical transmission device transmits a photographing control signal for controlling a photographing operation of the image pickup device supplied from outside via a second light beam. The first optical space transmission means receives the second light beam, demodulates the photographing control signal, and outputs the demodulated photographing control signal to the photographing direction control means. Remote imaging device. 5. The signal-to-noise ratio warning when the signal-to-noise ratio of the first light beam in the second optical space-transmitting means falls below a predetermined threshold. Transmitting information to said first spatial light transmission means via said second light beam, said first spatial light transmission means responding to said signal to noise ratio warning information, The remote imaging apparatus according to claim 1, wherein by controlling the oscillation wavelength of the beam, generation of noise due to absorption of the first light beam into the atmosphere is avoided. 6. The remote imaging apparatus according to claim 1, wherein the light beam has a wavelength of 1.4 [μm] or more. 7. An image capturing and transmitting apparatus for capturing an image of a predetermined imaging target to generate a video signal and transmitting the video signal via a light beam, wherein the imaging of the predetermined imaging target and generating a video signal is performed. Means, optical space transmission means for transmitting the video signal via a light beam, photovoltaic power generation means for photoelectrically converting light to generate power, and storing the power generated by the photovoltaic power generation means A secondary battery; and a power control unit that switches between the power generated by the photovoltaic power generation unit and the power stored in the secondary battery and supplies the power to the imaging unit and the optical space transmission unit. An imaging transmission device, comprising: 8. The optical space transmission means multiplexes the operation state information of the imaging means, the optical space transmission means, the photovoltaic power generation means, the secondary battery and the power supply means with the video signal, The imaging transmission apparatus according to claim 6, wherein the transmission is performed via the light beam. 9. The imaging and transmitting apparatus according to claim 6, wherein the light beam has a wavelength of 1.4 [μm] or more.