JPH04165598A - Optical space transmitter - Google Patents

Abstract

PURPOSE:To omit unnecessary initializing operation and to improve the convenience in use by releasing the servo state and setting the initial state only when an initializing operation piece is operated. CONSTITUTION:A control circuit 77 which controls the operation of irradiated position correcting means 56 to 58, 59A, 60 and 61 correcting the irradiated position by a transmission light beam LA1 in response to operation pieces 37 to 42 based on output signals IX1 to IY2 of a light receiving part 68, when an initializing operation piece 37 is operated, controls the irradiated position correcting means 56 to 58, 59A, 60 and 61 to stop the irradiated position correcting action and set the irradiated position by the transmission light beam LA1 at the center of the correcting action. Thus, by operating the initializing operation piece 37 as necessary, the initial state can be set and the unnecessary initializing action in the replacement of a power supply and the like can be eliminated.

Description

[Detailed description of the invention] The present invention will be explained in the following order.

A: Industrial field of application B: Overview of the invention C: Prior art (Figure 19) D: Problem to be solved by the invention (Figure 19) Eal! !
Means for solving (Fig. 2, Fig. 6, and Fig. 7) F action (Fig. 2, Fig. 6, and Fig. 7) G embodiment (Fig. 1 to Fig. 18) (G1) Light Schematic configuration of the space transmission device (Fig. 1) (Gl-
2) Transmission optical system (Fig. 2) (Gl-3) Collimating scope (Fig. 2) (Gl-4
) Anti-reflection mechanism (Figure 2) (Gl-5) Collimating scope arrangement (Figures 2 and 3) (Gl-6) Servo circuit (Figures 1 to 18) (Gl-
6-1) Correction of polarization plane (Gl-6-2) Correction of irradiation position (Gl-6-3) Servo stop control (Gl-6-4) Mirror configuration (Gl-7) System control circuit (G2 ) Operation of the embodiment (G3) Effects of the embodiment (G4) Other embodiments H Effects of the invention It can be applied to an optical space transmission device that transmits information.

B. Summary of the Invention The present invention prevents unnecessary initialization operations such as when replacing the power source by setting the irradiation position correction means to the initial state only when the initialization operator is operated in the optical space transmission device. Therefore, the usability of the optical space transmission device can be improved accordingly.

C. Conventional technology Conventionally, in an optical space transmission device, a part of a light beam with a predetermined polarization plane to be sent to a transmission target is folded back and observed together with observation light arriving from the transmission target, thereby easily irradiating the light beam. It has been proposed that the position can be confirmed (Japanese Patent Application No. 2-20916, Japanese Patent Application No. 1983).
-138120).

That is, as shown in FIG. 19, in the optical space transmission device 1, a laser diode 2 is driven by a predetermined information signal, and a light beam L having a predetermined polarization plane is emitted from the laser diode 2.
Inject AI.

The lens 4 converts the light beam LAI into a parallel light beam, and then transmits the parallel light beam through a polarizing prism 6 and guides it to a half mirror 8 .

Here, the half mirror 8 transmits a portion of the light beam LAI, and sends the transmitted light to the transmission target via lenses 16 and 18.

Thereby, the optical space transmission device 1 is configured to transmit a light beam LAI having a predetermined plane of polarization to a transmission target.

Further, the half mirror 8 returns the reflected light of the light beam LAI by the corner cube prism 10 and guides the folded light beam to the image pickup device 14 via the lens 12 .

As a result, in the optical space transmission device 1, a part of the light beam LAI sent to the transmission target is separated, its optical path is turned back, and the light beam is focused on the image sensor 14.

The lens 18 receives the light beam LA2 arriving from the transmission target and guides it to the polarizing prism 6 via the lens 16 and the half mirror 8.

Here, the transmission target emits a light beam LA2 whose polarization plane is orthogonal to the light beam LAI.

Thereby, the optical space transmission device 1 reflects the light beam LA2 by the polarizing prism 6, and then focuses the light beam LA2 onto the light receiving element 22 via the lens 22.

Thereby, the optical space transmission device 1 is able to receive information by receiving the light beam LA2 arriving from the transmission target.

Further, the lens 18 receives the light LL (hereinafter referred to as observation light) directed from the surrounding landscape of the transmission target toward the optical space transmission device 1 together with the light beam LA2, and transmits the observation light L1 to the lens 16 and the half mirror. 8. Guide to the image sensor 14 via the lens 12.

As a result, in the observation light Ll, a component whose optical axis is parallel to that of the light beam LA1 enters the lens 12 in parallel with the light reflected from the corner cube prism 100.

Therefore, the reflected light from the corner cube prism 10 follows an optical path to the lens 12 as if it were emitted from the irradiation position of the light beam LAX toward the optical space transmission device 1.
incident on .

As a result, in the optical space transmission device 1, the image sensor 14
It is possible to obtain a captured image in which a bright spot is formed at the irradiation position of the light beam LAI, and the light beam LAI can be easily
The irradiation position of X can be confirmed.

D Problems to be Solved by the Invention By the way, it would be convenient if the optical space transmission device 1 could be made smaller.

That is, in the optical space transmission device 1, the light beam LAI
By being able to easily detect the irradiation position of
Installation work can be simplified.

Therefore, it can be installed at a desired installation location as needed and used for, for example, television broadcasting.

The present invention has been made in consideration of the above points, and it is an object of the present invention to propose an optical space transmission device with improved usability when transmitting desired information using the optical space transmission device.

Eil! Means for Solving the Problem In order to solve the problem, in the present invention, a transmitted light beam L having a predetermined plane of polarization W1 modulated by a predetermined information signal S1 is provided.
By transmitting the AN to a transmitting/receiving device arranged a predetermined distance apart and receiving the receiving light beam LA2 of a predetermined polarization plane W2 sent from the transmitting/receiving device, the information signal S1 is transmitted via the transmitted light beam LA1. In the optical space transmission device 30, which transmits the information signal S2 to the transmitting/receiving device and receives a predetermined information signal S2 sent from the transmitting/receiving device via the receiving light beam LA2, a light beam 1151 that emits the transmitting light beam LAX and a light source 51 are used. The transmitted light beam L emitted from
A polarized light beam separation means 53 that reflects or transmits the AI and transmits or reflects the received light beam LA2 in contrast to the transmitted light beam LAI, and transmits and receives the transmitted light beam LAX obtained through the polarized light beam separation means 53. Optical systems 59A and 59B that send the received light beam LA2 to the device and also guide the received light beam LA2 arriving from the transmitting/receiving device to the polarized light beam separation means 53.
and a light receiving section 68 that receives the received light beam LA2 obtained via the polarized light beam separation means 53, and a transmitting light beam LAI based on the output signals IXI to IY2 of the light receiving section 68.
Irradiation position correction means 56.57.5 for correcting the irradiation position of
8.59A, 60.61, and irradiation position correction means 56.57.58.59A in response to the operations of the operators 37 to 42.
60.61, and when the initialization operator 37 is operated, the control circuit 77 controls the irradiation position correction means 56.57.58.59A, 60.61.
control to stop the correction operation of the irradiation position of the transmitting light beam LA.
The irradiation position of I is set as the center of the correction operation.

When the F action initialization operator 37 is operated, the irradiation position correction means 56, 57, 58, 59A, 60.61 are controlled to stop correcting the irradiation position, and the irradiation position of the transmitted light beam LAI is controlled to stop the correction operation. If it is set to the center of operation, it can be set to the initial state by operating the initialization operator 37 as necessary, and unnecessary initialization operations can be prevented when replacing the power source or the like.

G example An embodiment of the present invention will be described in detail below with reference to the drawings.

(G1) Schematic structure of optical space transmission device In FIG. 1, 30 indicates the optical space transmission device as a whole, which can be driven by power supplied from a power supply device 31.

That is, the power supply device 31 houses a battery therein, and when a power switch 31A provided on the front is turned on, power from the battery is supplied to the optical space transmission device main body 34 via a cable 31B.

As a result, the optical space transmission device main body 34 comes into operation in response to the operation of the power switch 31A provided on the power supply device 31 side, and thus, in the optical space transmission device 30, the battery can be easily removed from the power supply device 31 side. It is designed to be exchangeable.

The optical space transmission device main body 34 is mounted on a pedestal 35 so that it can be installed at a predetermined position. The irradiation position of the light beam LAI can be confirmed.

Furthermore, the optical space transmission device main body 34 has an initialize switch 37 at the top of the operation panel, and when the initialize switch 37 is turned on, the irradiation position adjustment mechanism of the light beam LAI is reset to the center of operation. ing.

Furthermore, the optical space transmission device main body 34 has operators 38A to 38D for adjusting the irradiation position under the initialization switch 37.
When the operators 38A to 38D are turned on, the light beams L are turned on corresponding to the operators 38A to 38D, respectively.
The AI irradiation position can be adjusted in four directions: up, down, left, and right.

Further, when the servo switch 39 is turned on after adjusting the irradiation position of the light beam LA1, the optical space transmission device main body 34 corrects the irradiation position of the light beam LAI based on the light beam LA2 arriving from the transmission target. However, the correction state can be visually confirmed by lighting the light emitting elements 40A and 40B.

Furthermore, below the servo switch 39 is a monitor switch 4.
1 and a zoom operator 42 are arranged, and when the monitor switch 41 and the zoom operator 42 are turned on, the display screen is switched to the on state, and the magnification of the display screen is varied.

A monitoring indicator 43 is arranged below the display screen 36, and the light intensity of the light beam LA2 arriving from the transmission target can be monitored by the pointer of the indicator 43.

Furthermore, connectors 44 and 45 are arranged at the bottom of the operation panel, and are configured to output the received video signal and communication signal to the outside, respectively.

(Gl-2) Transmission optical system As shown in FIG. 2, the optical space transmission device main body 34 houses a transmission optical system 48 inside a rectangular housing, and communicates with the transmission target via the transmission optical system 48. Light beam between LAI and L
Send and receive A2.

That is, the drive circuit 50 drives the laser diode 51 with a desired information signal S1 to be transmitted.

The laser diode 51 is connected to the optical space transmission device main body 34
It is held at a predetermined inclination with respect to the casing of the optical space transmission device 34, thereby emitting a light beam LAI whose polarization plane W1 is inclined by approximately 45 degrees with respect to the horizontal axis of the optical space transmission device main body 34.

The lens 52 converts the light beam LAI emitted from the laser diode 51 into a parallel light beam, and then converts it into a parallel light beam.
3 is transmitted and guided to a mirror 56 via a lens 54 and a lens 55.

Here, the mirror 56 is 4
The optical axis of the light beam LAI is bent approximately 90 degrees in the horizontal direction.

On the optical axis of the bent light beam LAI, there is a mirror 5 that is also tilted at 45 degrees with respect to the optical axis of the light beam LAI.
7 is arranged so that the optical axis of the light beam LAI bent by the mirror 56 is turned back substantially parallel to the original optical axis.

At this time, in the mirrors 56 and 57, the servo circuit 5
Based on drive signals SXI and SY1 outputted from 8, it is configured to rotate by a small angle in the horizontal and vertical directions, as shown by arrows a and b, respectively.

As a result, the mirrors 56 and 57 slightly angularly displace the optical axis of the light beam LA1 in the vertical and horizontal directions, and finely correct the exit direction of the light beam LAI that is emitted from the optical space transmission device main body 34.

The lens 59A receives the light beam LA reflected by the mirror 57.
After condensing the light I, it is sent to the transmission target via the lens 59B, thereby sending out the light beam LAY with a predetermined spread to the transmission target.

At this time, the lens 59A, as shown by arrows C and d,
Driven by motors 60 and 61, the drive signal S is rotated vertically and horizontally, and is thereby outputted from the servo circuit 58.
Based on X2 and SY2, the emission direction of the light beam LAI is roughly adjusted.

As a result, in the optical space transmission device main body 34, the mirrors 56 and 57 and the lens 59A are movable, and even when the optical space transmission device main body 34 vibrates due to wind etc., the light beam L
It is designed to reliably irradiate the transmission target with AI.

The light beam LA2 arriving from the transmission target is received by the lens 59B, travels backward along the optical path of the light beam LAI,
The light enters the polarizing prism 53.

Here, the light beam LA2 is emitted from the transmission target such that the polarization plane W2 is perpendicular to the polarization plane W1 of the light beam LA1.

As a result, the light beam LA2 is reflected by the polarizing prism 53 and enters the half mirror 62.

Here, the half mirror 62 focuses the light beam LA2 onto the light receiving element 64 via the lens 63.

Thereby, in the optical space transmission device main body 34, the output signal of the light receiving element 64 is demodulated by the signal processing circuit 65, thereby receiving the information signal S2 transmitted from the transmission target.

Furthermore, the half mirror 62 reflects the light beam LA2 and focuses the light beam LA2 on the light receiving surface of the position detection sensor 68 via the filter 66 and the condensing lens 67.

Here, the position detection sensor 68 is formed by a two-dimensional position detection sensor that outputs output signals IXI to IY2 according to the position of the light spot formed on the light receiving surface. Based on this, the emission position of the light beam LA2 with respect to the optical space transmission device main body 34 can be detected with high accuracy.

That is, the servo circuit 58 outputs the output signals IX1 to IY.
2, an error signal is generated by performing addition/subtraction page processing, and drive signals SXI to SY2 are output based on the error signal.

As a result, the servo circuit 58 corrects the irradiation position of the light beam LA1 based on the light beam LA2, and even if the optical space transmission device body 34 vibrates due to wind or the like, the light beam LAI can be reliably transmitted to the target. It is designed to irradiate.

(Gl-3) Collimating Scope A collimating scope A is arranged on the optical path between the mirror 57 and the lens 59A, so that the irradiation position of the light beam LAI can be visually confirmed on the display screen 36.

That is, the collimating scope A has a half mirror 69 disposed on the optical path of the light beam LAX, and reflects a part of the light beam LAI.

At the same time, the half mirror 69 receives observation light from the surrounding landscape of the transmission target toward the optical space transmission device 1, and transmits the observation light 1 to the lens 59.
B, 59A, the observation light 1 is reflected in the opposite direction to the light beam LAI, and then enters the imaging optical system 70.

The corner cube prism 71 receives the reflected light LRI of the light beam LA1, returns the optical path of the reflected light LRI in parallel, and then passes the reflected light LRI back to the imaging optical system 70 via the half mirror 69.
lead to.

The imaging optical system 70 focuses the reflected light LRI and the observation light L1 on a built-in image sensor, and outputs an output signal of the image sensor to the image signal processing circuit 72.

The image signal processing circuit 72 converts the output signal of the image sensor into a video signal and outputs it to the monitor device 73, thereby transmitting the light beam LAI onto the scenery to be transmitted via the display screen 36 on the operation panel. The irradiation position can be observed as a bright bright spot.

At this time, in the imaging optical system 70, the zoom drive circuit 7
4 to vary the magnification.

As a result, in the optical space transmission device main body 34, after roughly adjusting the irradiation position of the light beam LA1 at a low magnification, the magnification is successively increased and readjusted, and the servo circuit 58 is operated within a predetermined range. Easy light beam L
The AI irradiation position can be adjusted.

(Gl-4) Anti-reflection mechanism Here, a shutter 75 is inserted between the corner cube prism 71 and the nozzle mirror 69, and by opening and closing the shutter as necessary, the light beam LAI is prevented during communication. It is designed to prevent the light from returning to the light receiving element 64.

That is, in the shutter 75, the shutter drive circuit 7
6, and switches from the light shielding state to the open state in conjunction with the imaging signal processing circuit 72.

As a result, when the monitor switch 41 is turned on, the optical space transmission device main body 34 forms a display image on the display screen 36 based on the control signal S01 output from the system control circuit 77, and also displays the display screen. The irradiation position of the light beam LAI can be confirmed through the light beam LAI.

Therefore, by turning off the monitor switch 41 after adjusting the irradiation position of the light beam LAI, the optical path of the light beam LAI reflected by the half mirror 69 can be blocked.

That is, when the shutter 71 is closed, the nof mirror 6
After the light beam LAI reflected by the corner cube prism 71 is reflected by the corner cube prism 71, it passes through the half mirror 69, the mirror 57.56, the lens 55.54, the polarizing prism 53, the half mirror 62, and the lens 63 to the light receiving element 64. The optical path leading to this point can be blocked.

Therefore, the occurrence of crosstalk can be reduced accordingly, and information can be received reliably.

Furthermore, in this case, the light beam LAI can be prevented from returning to the laser diode 51 at the same time, and the light beam L can be stabilized accordingly.
It can fire AI.

(Gl-5) Arrangement of collimating scope As shown in FIG. 3, collimating scope A is housed in a predetermined housing 78 and rotates as shown by arrow e around the optical axis of lens 59B. It is made to be obtained.

That is, the housing 78 has windows 69 in front and behind the half mirror 69.
A and 69B are provided, and the cylindrical projections of holding members 79A and 79B are fitted into the windows 69A and 69B to be held from the front and back.

As a result, the light beam LA passes through the circular tube-shaped introduction portions 79C and 79D formed inside the windows 69A and 69B.
I, LA2 and observation light L1 are incident on the half mirror 69.

As shown in FIG. 4, the holding members 79A and 79B have their base portions fixed to the casing 80 of the optical space transmission device main body 34, so that the windows 6gA and 69 are attached to the circular tube-shaped projections.
Slide B so that the entire collimating scope A is aligned with lens 5.
It is designed to be able to rotate around the optical axis of 9B.

Further, in this embodiment, the housing 80 is formed in a rectangular shape, whereas the collimating scope A has the housing 80 shaped like a rectangle.
The entire device is held tilted in the diagonal direction of 0.

That is, when constructing an optical space transmission device using the collimating scope A in this way, it is inevitable that the corner cube prism 71 and the imaging optical system 70 protrude from the lens barrel of the transmission optical system 48. , the overall shape becomes larger accordingly.

Furthermore, as the size increases, the weight also increases, and portability is also impaired.

Therefore, in the optical space transmission device main body 34, by tilting and holding the collimating scope A in the diagonal direction, the internal space of the housing 80 can be effectively used to store the collimating scope A, thereby reducing the overall size. be able to.

Therefore, the overall weight can be reduced accordingly, and portability can be improved.

In addition, by holding the lens 59A so as to be able to rotate with respect to the optical axis, the shape of the housing 80 to be incorporated and the shape of the housing 80 can be changed.
The collimating scope A can be arranged at various inclinations depending on the arrangement of components within the spacer 0, thereby allowing the transmission optical system to be commonly used in various optical space transmission devices.

Furthermore, at this time, in the corner cube prism 71 housing part of the housing 78 (that is, the upper part of the housing 78), according to the shape of the corner cube prism 71,
The corner portions extending from front to back are largely chamfered.

As a result, in the housing 78, the collimating scope A
When holding the collimating scope A with the entire body tilted diagonally, the housing 8
This is done so that no wasted space is generated within 0.

By the way, when the collimating scope A is held tilted in this manner, a tilted display image is displayed on the display screen 36 accordingly.

For this reason, the imaging optical system 70 of the collimating scope A is held rotatably about the optical axis of the imaging optical system 70 with respect to the housing 78, as shown by the arrow f. There is.

As a result, in the optical space transmission device main body 34, the imaging optical system 70 is rotated according to the inclination of the collimating scope A, so that the horizontal and vertical directions are displayed correctly on the display screen 36.

Note that the imaging optical system 70 is also formed to have a small tip, similar to the housing portion of the corner cube prism 71, so that no wasted space is created within the housing 80.

In this way, the overall shape can be reduced in size, and the usability of the optical space transmission device 30 can be improved accordingly.

(Gl-6) Servo circuit The servo circuit 5 operates the system control circuit 7 in response to the operation of the servo switch 39 and the initialization switch 37.
When the control signal SC2 is output from 7, it rises to the operating state.

Thereby, the servo circuit 58 corrects the irradiation position of the light beam LAY and the polarization plane W1 of the light beam LAI based on the output signals IXI to IY2 of the position detection sensor 68,
It is designed to ensure that information can be sent and received.

(Gl-6-1) Correction of polarization plane As shown in FIG. 5, in the transmission optical system 48, the optical system from the laser diode 51 to the polarizing prism 53,
The optical system from the polarizing prism 53 to the position detection sensor 68 and the light receiving element 64 is integrally held in the lens barrel 81.

At this time, with respect to the polarization plane W1 of the laser diode 51,
The polarizing prism 53 is held so that the planes of polarization in the transmission direction match.

As a result, in the optical space transmission device main body 34, when the polarization plane Wl of the light beam LAX is maintained at an angle of 90 degrees with respect to the light beam LA2, the polarization prism 53
The incident light beam LA2 is entirely reflected by the polarizing prism 53, so that the light beam LA2 is most efficiently incident on the position detection sensor 68.

The lens barrel 81 is connected to the main body of the transmission optical system 48 (that is, the optical system from the mirror 56 to the lens 59B) through bearings 81A and 81B arranged so as to surround the periphery, as shown by arrow g. It is held rotatably.

As a result, the optical space transmission device main body 34 rotates the lens barrel 81 and holds it in a predetermined position, so that the light beam LA2
The polarization plane W1 of the light beam LA1 can be adjusted with respect to the polarization plane W2 of the light beam LA1.

That is, in the servo circuit 58, the polarization plane servo circuit 8
2 provides the output signals IX1 to IY2 of the position detection sensor 68 to the detection circuit 83.

The detection circuit 83 adds the output signals IXI to IY2 to detect the light beam LA incident on the position detection sensor 68.
Detect the light intensity of 2.

The comparison circuit 84 takes in the detection results of the detection circuit 83 at a predetermined period, sequentially obtains comparison results, and thereby detects a change in the amount of light beam LA2 incident on the position detection sensor 68.

When the control signal SC2 rises, the drive circuit 85 drives the motor 86 based on the detection result, thereby moving the lens barrel 81 in a direction in which the amount of light incident on the position detection sensor 68 increases.
is rotated, and when the amount of incident light decreases, the direction of rotation is switched.

As a result, the optical space transmission device main body 34 determines the polarization plane W2 of the light beam LA2 based on the amount of light incident on the position detection sensor 68.
The polarization plane W1 of the light beam LAI and the polarization plane of the polarizing prism 53 are corrected so that the polarization plane W1 of the light beam LAI and the polarization plane W1 of the light beam LAI are orthogonal to each other.

Therefore, even if the optical space transmission device main body 34 is installed at an angle, the polarization plane can be automatically adjusted and the light beam LA2 can be made to efficiently enter the light receiving element 64, thereby reducing the adjustment work when opening the separate parts. It can be simplified.

Furthermore, even if the entire optical space transmission device main body 34 vibrates to the left or right, the plane of polarization is automatically adjusted and the light beam L
A2 can be made to enter the light receiving element 64 efficiently.

Therefore, even when desired information is transmitted by being mounted on a ship, vehicle, aircraft, satellite, etc., the information can be reliably received.

Furthermore, with respect to the transmission target, the polarization plane W2 of the light beam LA2
A light beam LA whose polarization plane W1 is tilted by exactly 90 degrees with respect to
The optical beam LAI can be transmitted and the optical beam LAI can be reliably received at the transmission target, and thus the information signals S1 and S2 can be reliably transmitted and received.

(Gl-6-2) Correction of irradiation position As shown in FIG. 6, in the servo circuit 58, the output signals IXI to IY2 of the position detection sensor 68 are sent to the X-direction position detection circuit 86A and the X-direction position detection circuit 86B. give,
Detect error signals VERX and VERY.

That is, as shown in FIG.
A is the output signal IX1 and IX2 of the position detection sensor 68
is applied to current-voltage conversion circuits 87A and 87B.

The subtraction circuit 88A and the addition circuit 88B receive output signals V output from the current-voltage conversion circuits 87A and 87B, respectively.
Outputs subtraction signals and addition signals of XI and VX2.

The division circuit 89 divides the subtraction signal output from the subtraction circuit 88A by the addition signal output from the addition circuit 88B, and outputs the division result as an error signal VERX.

Here, as shown in FIG. 8, in the position detection sensor 68, when the light beam LA2 is focused on the light receiving surface made of a photoelectric conversion film, a current is generated in the resistive layer according to the focused position of the light beam LA2. flows, and the ratio of the output currents 11 and I2 changes.

As a result, the X-direction error signal VERX expressed by the following relational expression 1 can be obtained via the division circuit 89, and the condensing position of the light beam LA2 can be detected.

Here, 1 represents a constant.

The X-direction position detection circuit similarly performs addition/subtraction processing on the output signals IYI and IY2 of the position detection sensor 68, and generates an X-direction error signal VERY.

Thereby, the positional deviation of the light beam LA2 can be detected based on the error signals VERX and VERY, and based on the detection result, the mirror 56, 58 and the lens 58A are driven to correct the irradiation position of the light beam LAI. can do.

By the way, in the position detection sensor 68, the light beam LA
In addition to 2, the incidence of the light beam LAI reflected by the lenses 59A, 59B, etc. inevitably causes measurement errors in the error signals VERX and VERY.

Therefore, in this embodiment, when installing, the light beam LA
After interrupting the transmission of 2 and detecting the measurement error, the error signals VERX and VERY are corrected based on the detection result, thereby preventing a decrease in measurement accuracy.

That is, in the X direction, the output signal components of the light receiving element 68 due to reflected light are set as IIE and I2E, and the light beam LA
If the components due to 2 are set as 11 and I2, the output signal IXI
and IX2 can be expressed as the following equation (1) % (2) By substituting this into equation (1), it can be expressed as the following equation ERX (4).In the end, the position detection sensor is It can be seen that it is sufficient to detect the output signals IXE and I2E of 68 and subtract them from the output signals IXI and IX2 when the light beam LA2 is incident.

For this reason, in the servo circuit 58, during installation, the transmission of the light beam LA2 is interrupted and the current-voltage conversion circuits 87A and 88
7B (7) Detect output voltages VE1 and VB2.

Further, current-voltage conversion circuits 87A and 87B and subtraction circuit 8
A subtraction circuit 90A is provided between each adder circuit 8A and an adder circuit 88B.
and 90B, the detected output voltages VEI and VB2 are subtracted from the output signals of the current-voltage conversion circuits 87A and 87B when the light beam is irradiated onto A2, thereby correcting the error signal VERX.

Actually, the laser diode 51 is APC(aut.

A light beam LAl is emitted so that the light intensity is constant by driving the light beam using a matic power control circuit.

Therefore, the intensity of the light beam LAN reflected by the transmission optical system 48 and incident on the position detection sensor 68 is equal to the intensity of the light beam LA
Regardless of the presence or absence of light reception in step 2, it can be determined that the value is approximately constant.

Therefore, as in this embodiment, the measurement accuracy can be improved by detecting the output signal of the position detection sensor 68 without receiving the light beam LA2 and correcting the error signals VERX and VERY based on the detection result. can.

In this way, even when the transmission distance increases and the intensity of the light beam LA2 decreases, highly accurate error signals VERX and VERY can be obtained, and the transmission target can be reliably irradiated with the light beam LAI.

That is, when the control signal SC2 rises, the servo signal output circuit 91 amplifies the error signals VERX and VERY, and then outputs the amplified error signals VERX and VERY.
The drive signals SX2 and S are passed through the low-pass filter circuit.
Output as Y2.

As a result, the servo circuit 58 is connected to the drive motors 60 and 61.
to correct gradual fluctuations in the light beam irradiation position.

Furthermore, the servo signal output circuit 91 extracts the high frequency components of the amplified error signals VERX and VERY and outputs the drive signal SX.
I and SYI, and generate the corresponding drive signals SXI and SYI.
The mirrors 56 and 57 are driven based on this, thereby driving the mirrors 56 and 57 at high speed to correct the irradiation position of the light beam LAI.

Furthermore, at this time, the servo signal output circuit 91
．． Drive signals SXI to SY2 are output so that the center of displacement of mirror 56.57 is at the position of 0 displacement of mirror 56.57, thereby preventing the center of displacement of mirror 56.57 from being displaced from the support center.

Note that, after the control signal SC2 falls, when the system control circuit 77 outputs the control signals sx, sy in response to the operations of the operators 38A to 38D, the servo signal output circuit 91 outputs the control signals SX, sy. Drive signal SX according to SY
2 and SY2, thereby operating the operators 38A to 38.
D can be operated to adjust the irradiation position of the light beam LAI.

(Gl-6-3) When the servo stop control signal processing circuit 65 demodulates and outputs the output signal of the light receiving element 64, it detects and outputs the signal level of the output signal.

Thereby, the signal processing circuit 65 is configured to detect the amount of light incident on the light receiving element 64.

The comparison circuit 94 obtains a comparison result between the detection result of the signal processing circuit 65 and a predetermined comparison standard at a predetermined period, and outputs the comparison result to the servo signal output circuit 91.

As a result, the servo signal output circuit 91 outputs the light beam LA2.
detects a decrease in the light intensity of the light beam LA2, and when the light intensity of the light beam LA2 falls below a predetermined value determined by the comparison standard, the drive signals SX1 to S
Stop the output of Y2.

As a result, the servo signal output circuit 91 outputs the light beam LA2.
When the accuracy of the error signals VERX and VERY decreases due to a decrease in the amount of light, the servo operation is controlled to stop, effectively avoiding malfunctions of the entire servo circuit.

As a result, even if the light intensity of the light beam LA2 decreases,
The irradiation positions of the light beams L and L can be maintained so as not to be displaced in a direction completely unrelated to the transmission target, and the servo operation can be reliably performed immediately after the light intensity of the light beam LA2 returns to a predetermined value or more. There is.

Therefore, it is possible to omit readjustment work for the irradiation position of the light beam LAI when the light intensity of the light beam LA2 decreases.
The usability of the optical space transmission device 30 can be improved accordingly.

The incident light amount detection circuit 96 adds the output signals IX1 to IY2 of the position detection sensor 68, and thereby detects the amount of incident light beam LA2 incident on the position detection sensor 68.

Here, as shown by the symbol T in FIG.
Narrow band filter 6 set to have A20 wavelength
7 is arranged.

The comparison circuit 97 obtains a comparison result between the detection result of the incident light amount detection circuit 96 and the incident light amount detection result of the signal processing circuit 65, and outputs the comparison result to the servo signal output circuit 91 when the following formula % formula % (5) is satisfied. death,
This controls the output of the drive signals SXI to SY2 to stop.

Here, α is a predetermined constant.

That is, as shown in FIG. 10, a narrow band filter 67 that transmits the light beam LA2 is provided in front of the position detection sensor 68.
Due to the arrangement, when broad-band sunlight enters the optical space transmission device main body 34, the amount of light incident on the light receiving element 68 increases significantly compared to the amount of light incident on the position detection sensor 64.

Therefore, by obtaining a comparison result of the amount of incident light on the light receiving element 68 and the position detection sensor 64, it can be determined whether the increase in the amount of incident light is due to sunlight.

As a result, the optical space transmission device 30 stops the servo operation based on equation (5), and controls the servo operation to stop when the accuracy of the error signals VERX and VERY decreases due to the incidence of sunlight.

As a result, the optical space transmission device 30 maintains the irradiation position of the light beam LAI so that it does not shift in a direction completely unrelated to the transmission target even when sunlight is incident, and reliably maintains the irradiation position of the light beam LAI from immediately after sunlight ceases to be incident. It is designed for servo operation.

Therefore, it is possible to omit readjustment work when sunlight is incident on the irradiation position of the light beam LAI, and the usability of the optical space transmission device can be improved accordingly.

(Gl-6-4) Structure of Mirrors As shown in FIG. 11, mirrors 56 and 57 are supported by the lens barrel of the main body of the transmission optical system 48 via predetermined holding members.

That is, the bearings 100A and 100B are the rotating members 1
01 is pivotally supported from both sides, thereby rotating the rotating member 101.
Hold it so that it can rotate freely as shown by the arrow.

As shown in FIG. 12, the rotating member 101 holds the mirror support member 102 and the vibration damping member 103 so as to sandwich them therebetween.

Here, the vibration damping member 103 is made of a rubber-like sheet material that absorbs vibrations, and is formed by cutting the sheet material into a predetermined shape.

The mirror support member i02 is constituted by a bimorph plate made of a piezoelectric element, so that its tip is displaced in response to an applied voltage as shown by an arrow i.

The tip of the mirror support member 102 is inserted and bonded into the U-shaped groove of the adhesive base 104, and the mirror 5 is inserted through the adhesive base 104.
6 (57) is retained.

As a result, in the optical space transmission device main body 34, the drive signals SX1 and SYI are applied to the mirror support member 102 to displace the mirror 56 (57).
The irradiation position of the light beam LAI is corrected by the displacement.

The bearings 100A and 100B are configured such that the rotating member 101 can be fixed by screwing screws 105A and 105B into the tapped holes provided in the bearings, so that the mirrors 56 and 57 can be mounted in the same position. It is designed so that it can be adjusted.

In this way, by using the bimorph plate to displace the mirrors 56 and 57 to correct the irradiation position of the light beam LAI, the irradiation position of the light beam LAI can be corrected with a simple configuration.

Furthermore, the response speed can be improved compared to the case where a galvanometer mirror is used, and information can be transmitted more reliably.

The entire surface of the vibration damping member 103 is bonded to the mirror support member 102.

That is, when a bimorph plate is used in this way, there is a problem that the resonant frequency of the bimorph plate is low.

As shown in FIGS. 13 and 14, when the mirror is simply supported by the bimorph plate 102, the frequency is 88.5.
(7), a resonance point of 14 [dB:l appears (Fig. 14 (
A)), and the phase changes by up to 1190 degrees (first
Figure 4 (B)).

This makes it difficult to increase the gain of the servo circuit 58 and improve the tracking speed.

On the other hand, as shown in FIGS. 15 and 16, when a rubber-like sheet member 106 is attached to the back surface of the bimorph plate 102, the resonant frequency increases to 95 [ce] and becomes 16
(A)), the phase delay also decreases to 1172 degrees (16th
Figure (B)).

Furthermore, as in this embodiment, if the damping member 103 is attached to the bimorph plate 102 and held between the rotating members 101, the resonant frequency increases to 160 (Hz) as shown in FIG. Figure 17 (A)), the phase delay can also be reduced to 1130 degrees (Figure 17 (B)
).

Therefore, the frequency characteristics of the bimorph plate 102 can be improved, and the configuration of the servo circuit 58 can be simplified accordingly.

Furthermore, the irradiation position of the light beam LA1 can be corrected by following vibrations and the like at a high speed, and the response speed can be improved accordingly.

Furthermore, in this embodiment, the adhesive table 104 is spaced apart from the bimorph plate 102 by a predetermined distance gID, and the mirror 56-
(57) is held.

That is, as shown in FIG. 18, when the bimorph plate 102 and the mirror 56 (57) are arranged close to each other, when the bimorph plate 102 is displaced toward the mirror 56 (57), the lower end of the mirror 56 (57) There are cases where the mirror 56 (57) comes into contact with the bimorph plate 102 and the displacement of the mirror 56 (57) is restricted.

Therefore, in the optical space transmission device 30, the bimorph plate 1
A mirror 56 (57) is spaced a predetermined distance from 02.
By holding this, even if the bimorph plate 102 is largely displaced, the irradiation position of the light beam LAI can be reliably corrected.

(Gl-7) System control circuit The system control circuit 77 is composed of an arithmetic processing circuit and controls the entire main body of the optical space transmission device.

That is, when the system control circuit 77 receives power from the power supply device 31, it outputs a control signal SC2 to the servo circuit 58, and starts the optical space transmission device main body 34 into a servo state.

When the initialization switch 37 is turned on in this state, the system control circuit 77 outputs a control signal SCI to drive the motors 60 and 61, and sets the lens 59A at the center of rotation.

Thereby, the system control circuit 77 sets the optical space transmission device 30 to an initial state for adjusting the irradiation position of the light beam LAI.

That is, the system control circuit 77 controls the operators 38A to 38.
When D is turned on, control signals SX and SY are output to the servo circuit 58 in response to the operations of the operators 38A to 38D, and the lens 59A is rotated.

At this time, the system control circuit 77 controls the monitor switch 41
When turned on, the control signal SCI is output to display the display screen 36, and in response to the turned on operation of the zoom operator 42, the magnification of the imaging optical system 700 is switched.

Therefore, in the user's case, the initialize switch 37
After turning on the servo switch 39, the irradiation position of the light beam LAI can be easily adjusted by operating the operators 38A to 38D. After the adjustment, by turning on the servo switch 39, the light beam LAI can be reliably irradiated.

On the other hand, when the power supply is interrupted, a predetermined locking mechanism is activated to hold the lens 59A at the position immediately before the power is turned off.

Thereby, in the system control circuit 77, even if, for example, communication is interrupted and the battery is replaced, communication can be promptly resumed after the battery is replaced.

In other words, each time the power is turned on, if the lens 59A is rotated and set to the initial state, the initialize switch 37
can be omitted to reduce the number of bone manipulators.

However, in this case, even if the battery is simply replaced, the irradiation position of the light beam LA1 is unnecessarily initialized each time, and it is necessary to readjust the irradiation position of the light beam LAI.

Therefore, as in this embodiment, the initialize switch 37
By providing a separate controller and starting up the optical space transmission device main body 34 so that it operates as a servo when the power is turned on, the servo state can be canceled only when necessary, and adjustment work when turning on the power can be performed as necessary. Can be omitted.

Therefore, the usability of the optical space transmission device 30 can be improved accordingly.

Thus, in the optical space transmission device 34, when communication is interrupted, communication can be immediately resumed by starting supply of power.

When the system control circuit 77 enters the servo state,
The light emitting element 40A is turned on.

In this state, based on the error signals VERX and VERY from the servo circuit 58, the system control circuit 77 determines that if the light beam LA2 is focused within a predetermined range on the light receiving surface of the position detection sensor 68, the system control circuit 77 determines that it is in a servo ripple state. , lights up the light emitting element 40B.

Therefore, if the light emitting element 40A is lit and the light emitting element 40B is not lit, it can be determined that the irradiation position of the light beam LAI cannot be corrected.

As a result, the user can operate the initialize switch 37 and the operators 38A to 38D again to readjust the irradiation position of the light beam LAI, and then turn on the servo switch 39 to ensure that the transmission target is A light beam LAI can be irradiated.

Further, the system control circuit 77 is configured to ignore any on operation of the operators 38A to 38D unless the initialization switch 37 is turned on, thereby effectively avoiding user's erroneous operation.

By the way, if the amount of rotation of the lens 59A becomes too large, a case may occur in which, for example, the servo operation can follow a large displacement on the left side, but cannot follow a large displacement on the right side.

Therefore, the system control circuit 77 controls the motors 6° and 61
Limit switches 108 and 10 provided on the rotating shaft of
9, the amount of rotation of the lens 59A is detected, and when the amount of rotation exceeds a predetermined value, the buzzer circuit 116 is driven.

As a result, the system control circuit 77 generates a buzzer sound to alert the user when the amount of rotation exceeds a predetermined value.

(G2) Operation of the embodiment The light beam l-Al with a predetermined polarization plane W1 emitted from the laser diode 51 (FIG. 2) is converted into a parallel light beam by the lens 52, and then transmitted through the polarizing prism 53 and then 5
4 and lens 55, and is reflected by mirrors 56 and 57.

Here, the light beam LAI reflected by mirrors 56 and 57
After passing through the half mirror 69, it is sent to the transmission target via lenses 59A and 59B.

At this time, the drive signal sX1 output from the servo circuit 5
The bimorph plate 102 (FIG. 11) is displaced by SYI, and the mirrors 56 and 57 held at the tip of the bimorph plate 102 are displaced by small angles in the horizontal and vertical directions as shown by arrows a and b, respectively. , the irradiation position of the light beam LAI is corrected.

In response to this, the drive signal S output from the servo circuit 58
Based on X2 and SY2, motors 60 and 61 rotate lens 59A vertically and horizontally as shown by arrows C and d, thereby roughly correcting the irradiation position of light beam LAX.

As a result, in the optical space transmission device main body 34, the mirrors 56 and 57 and the lens 59A are movable, and even when the optical space transmission device main body 34 vibrates due to wind etc., the light beam L
It is designed to reliably irradiate the transmission target with AI.

The light beam LA2 arriving from the transmission target is received by the lens 59B, travels backward along the optical path of the light beam LAI,
The light enters the polarizing prism 53.

Here, the light beam LA2 has a polarization plane W1 of the light beam LAI.
On the other hand, the light is emitted from the transmission target so that the plane of polarization W2 is perpendicular to the polarization plane W2, and after being reflected by the polarizing prism 53, it enters the half mirror 62.

Here, a part of the light beam LA2 is focused on the light receiving element 64 via the lens 63, thereby making it possible to receive the information signal S2 transmitted from the transmission target.

Further, the remaining part of the light beam LA2 is filtered by a filter 66,
The light is focused on the light-receiving surface of the position detection sensor 68 via the condenser lens 67, so that the exit position of the light beam LA2 relative to the optical space transmission device main body 34 can be detected with high accuracy.

A portion of the light beam LAI is separated when passing through the half mirror 69 and guided to the corner cube prism 71 via the shutter 75 .

Here, the light beam LAI is turned back so that its optical path is parallel, and passes through a shutter 75 and a half mirror 69 to an imaging optical system 70.
guided by.

At this time, observation light beam 1 directed from the scenery around the transmission target toward the optical space transmission device 30 is received via lenses 59B and 59A, reflected by a half mirror 69, and guided to an imaging optical system 70.

Thereby, the irradiation position of the light beam LAI can be confirmed via the imaging optical system 70.

At this time, in the imaging optical system 70, the zoom drive circuit 7
4 to change the magnification, and as a result, in the optical space transmission device main body 34, after roughly adjusting the irradiation position of the light beam LAI at a low magnification, the magnification is sequentially increased to adjust the irradiation position, By operating the servo circuit 58 within a predetermined range, the irradiation position of the light beam LAI can be easily adjusted.

The output signals IXI-IY2 (FIGS. 6 and 7) of the position detection sensor 68 are input to the X-direction and Y-direction position detection circuits 86A and 86B of the servo circuit 58, where they are subjected to addition and subtraction processing to produce an error signal VERX. and VBERY are detected.

The error signals VERX and VERY are inputted to the servo signal output circuit 91, whereby the error signal VE
Based on RX and VERY, the motors 60 and 61 are driven to displace the mirrors 56 and 57, and the light beam LAI
Correct the irradiation position.

If the power supply is interrupted in this state, a predetermined locking mechanism operates to hold the lens 59A at the immediately previous position.

Furthermore, when the supply of power is started, the system control circuit 7
7 outputs a control signal SC2 to the servo circuit 58, and after the locking mechanism is released, the optical space transmission device main body 34 enters the servo state.

As a result, in the optical space transmission device 30, even if communication is interrupted and the battery is replaced, for example, communication can be resumed immediately after replacement, and usability can be improved accordingly.

When the initialization switch 37 is turned on in this state, the system control circuit 77 outputs the control signal SCI, and the lens 59A is set at the rotation center position.

As a result, the optical space transmission device 30 transmits the light beam LAI.
The irradiation position is set to the initial state for adjustment.

Therefore, in the user's case, the initialize switch 37
After turning on, turn on controller 3 while monitoring the display screen.
By operating 8A to 38D, the irradiation position of the light beam LAI can be adjusted as necessary.

Thus, by canceling the servo state and setting it to the initial state only when the initialize switch 37 is turned on, the servo state can be canceled only when necessary, and adjustment work when replacing the power source can be omitted.

Therefore, the usability of the optical space transmission device 30 can be improved accordingly.

(G3) Effects of Embodiment According to the above configuration, by canceling the servo state and setting the initial state only when the initialize switch 37 is turned on, unnecessary initialization operations can be prevented; The usability of the optical space transmission device 30 can be improved.

(G4) Other Embodiments In the above-mentioned embodiments, a case has been described in which the lens 59A is rotated as a position correction means and the bimorph plate 102 is displaced. Alternatively, various position correction means can be widely applied, such as when the mirror is driven by a motor.

Further, in the above-described embodiment, a case has been described in which the servo status is displayed by lighting up a light emitting element, but the present invention is not limited to this, and for example, the servo status can be displayed on a display screen using a superimpose method. You can.

H Effects of the Invention As described above, according to the present invention, unnecessary initialization operations can be omitted by canceling the servo state and setting the initial state only when the initialization operator is operated. An optical space transmission device with improved usability can be obtained.

[Brief explanation of the drawing]

Fig. 1 is a perspective view showing an optical space transmission device according to an embodiment of the present invention, Fig. 2 is a route diagram showing its transmission optical system, Fig. 3 is a perspective view showing a collimating scope, and Fig. 4 is its arrangement. 5 is a route map for explaining polarization plane correction, FIG. 6 is a block diagram showing the servo circuit, FIG. 7 is a block diagram showing the position detection circuit, and FIG. 8 is the position detection sensor. 9 is a characteristic curve diagram showing the characteristics of the filter, FIG. 10 is a characteristic curve diagram showing the relationship between incident light, and 1st
Figure 1 is a perspective view showing the structure of the mirror, Figure 12 is a cross-sectional view of the mirror, Figure 13 is a cross-sectional view explaining how to support the mirror, and Figure 14 is a characteristic curve diagram showing its frequency characteristics. , FIG. 15 is a sectional view for explaining another method of supporting the mirror, FIG. 16 is a characteristic curve diagram showing its frequency characteristics, FIG. 17 is a characteristic curve diagram showing the frequency characteristics according to the embodiment, and FIG. 18 is a characteristic curve diagram showing the frequency characteristics. A side view showing another embodiment, and FIG. 19 is a route diagram showing a conventional optical space transmission device. 1.30... Optical space transmission device, 2.51...
...Laser diode, 4.12.16.18.20
．． 52.54.55.59A, 59B, 63.67...
...lens, 6.53 ...polarizing prism,
8.62.69...Half mirror-137...
...Initialize switch, 56.57...
・Mirror, 58...Servo circuit, 60.61・
...Motor, 64... Light receiving element, 68.
...Position detection sensor, 77...System control circuit.

Claims (1)

[Claims] A transmitting optical beam modulated with a predetermined information signal and having a predetermined plane of polarization is sent to a transmitting/receiving device arranged a predetermined distance apart, and receiving the predetermined plane of polarization transmitted from the transmitting/receiving device. an optical space that transmits the information signal to the transmitting/receiving device via the transmitting light beam by receiving a light beam, and receives a predetermined information signal sent from the transmitting/receiving device via the receiving light beam; In the transmission device, a light source that emits the transmitted light beam; and polarized light that reflects or transmits the transmitted light beam emitted from the light source and transmits or reflects the received light beam in contrast to the transmitted light beam. a beam separating means; an optical system that sends the transmitted light beam obtained through the polarized light beam separating means to the transmitting/receiving device, and guides the receiving light beam coming from the transmitting/receiving device to the polarized light beam separating means; a light receiving unit that receives the received light beam obtained through the polarized light beam separation unit; and an irradiation position correction unit that corrects the irradiation position of the transmitted light beam based on the output signal of the light receiving unit; and a control circuit that controls the operation of the irradiation position correction means in response to the operation of the irradiation position correction means, and the control circuit controls the irradiation position correction operation of the irradiation position correction means when the initialization operation is operated. An optical space transmission device characterized in that a stop control is performed and the irradiation position of the transmission light beam is set as the center of the correction operation.