JPH04165596A - Optical space transmitter - Google Patents

Abstract

PURPOSE:To reduce the size of the entire shape with the effective use of the space within a case by housing a collimatoscope in the prescribed case and arranging the entire device while inclining them. CONSTITUTION:A light source 51 irradiating a transmission light beam LA1, an optical systems 59A and 59B transmitting the transmission light beam LA1 to a receiver and receiving an observation light L1 from the surrounding of the receiver, a light branching means 69 reflecting the part of the transmission light beam LA1 and reflecting the observation light L1 in the opposite direction to the transmission light beam LA1, a light path returning optical system 71 returning in parallel the light path of the transmission light beam LA1 or the observation light L1 and an observation optical system 70 observing the returned transmission light beam LA1 or the reflected observation light L1 as well as the reflected observation light L1 or transmission light beam LA1, are housed in a case 80. The light branching means 69, the light path returning optical system 71 and the observation optical system 70 are arranged so that they are approximately perpendicular to the optical axis of the optical systems 59A and 59B and that they are in a row on the diagonal line of the case. Thus, the size of the entire shape can be reduced.

Description

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

A. Industrial field of application B. Outline of the invention C. Prior art (Figure 19) D. Problems to be solved by the invention (Figure 19) E1m! 1
Means for solving the problem (Figs. 2 and 4) 2 effects (Figs. 2 and 4) G embodiment (Figs. 1 to 17) (G1) Schematic configuration of optical space transmission device (Fig. Figure 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 (Gi-7) System control circuit (G2 ) Operation of the embodiment (G3) Effects of the embodiment (G4) Other embodiments H Effects of the invention This is suitable for application to an optical space transmission device that transmits information.

B. Summary of the Invention According to the present invention, the overall shape of an optical space transmission device can be reduced by arranging a collimating scope on a diagonal of the housing.

C. Conventional technology Conventionally, in this type of spatial optical transmission device, by folding back a part of the light beam sent to the transmission target and observing it together with the observation light coming from the transmission target, it is easy to determine the irradiation position of the light beam. A method has been proposed that allows confirmation of the above (Japanese Patent Application No. 20916/1999).

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 LA1 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 send out 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 reflected light beam to the image sensor 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 1-8 receives the light beam LA2 coming from the transmission target.
is received and guided to the polarizing prism 6 via a lens 16 and a 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 light from the optical space transmission device LA2 coming from the transmission target.

Furthermore, the lens 18 receives light (hereinafter referred to as observation light) Ll directed toward the optical space transmission device l from the surrounding landscape of the transmission target, along with the light beam LA2, and transmits the observation light Ll to the lens 16, the half mirror 8, It is guided to the image sensor 14 via the lens 12 (.

As a result, in the observation beam 1, a component whose optical axis is parallel to the light beam LA1 enters the lens 12 in parallel with the reflected light of the corner cube prism 10.

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

As a result, in the optical space transmission bag W1, 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 I 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 LA,
Since the irradiation position of I can be easily detected, the 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 aims to propose an optical space transmission device whose overall shape can be reduced in size.

E Means for Solving the Problems In order to solve the problems, in the present invention, a transmission light beam LA1 modulated with a predetermined information signal S1 is sent to a receiving device arranged at a predetermined distance. The information signal S1 is sent to the receiving device via the transmitted light beam LAI.
In the optical space transmission device 30 that transmits a transmission light beam LAI, a light source 51 that emits a transmission light beam LAI, and a light source 51 that transmits the transmission light beam LAI emitted from the light source 51 to a receiving device, and also transmits observation light 1 that comes from around the receiving device. Optical system 5 that receives light
9A, 59B, the optical systems 59A, 59B, and the light source 51, and the transmitted light beam L obtained through the light source 51.
A light branching means 69 that reflects a part of the AI and also reflects the observation light I obtained through the optical systems 59A and 59B in a direction opposite to the transmission light beam LAI, and a transmission beam reflected by the light branching means 69. The optical path folding optical system 7I folds the optical path of the light beam LAI or the observation light L1 in parallel, and the transmitted light beam L A 1 or the observation light L1 that has been folded back by the optical path folding optical system 71 is reflected by the light branching means 69. It is equipped with an observation optical system 70 for observing together with the observation light beam 1 or the transmission light beam LAI, and includes a light source 51, optical systems 59A and 59B, and a light branching means 6.
9. The optical path turning optical system 71 and the observation optical system 70 are housed in a rectangular housing 80, and the optical branching means 69, the optical path turning optical system 71, and the observation optical system 70 are arranged approximately with respect to the optical axes of the optical systems 59A and 59B. They are arranged diagonally on the housing 80 at right angles.

F-action light branching means 69, optical path folding optical system 71, and observation optical system 7
0 are arranged substantially perpendicular to the optical axes of the optical systems 59A and 59B and lined up on the diagonal of the rectangular housing 80,
Accordingly, the space inside the housing 80 can be used effectively, and the overall shape can be made smaller.

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. # It can be driven by ita supplied from the device 31.

That is, the power supply device 31 houses a battery therein, and when the t'a switch 31A provided on the front is turned on, the power supply device 31 supplies its battery's to the optical space transmission device main body 34 via the cable 31B.

As a result, the optical space transmission device main body 34 comes into operation in response to the operation of the TA 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. In the light beams 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
It is arranged at an angle of 5 degrees, thereby bending the optical axis of the light beam LA, 1 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 I, it is sent to the transmission target via the lens 59B, thereby sending out the light beam LAI 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 L A, 2 is transmitted through 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.

Further, the half mirror 62 reflects the light beam LA, 2 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 NY2 according to the position of the light spot formed on the light receiving surface, and the eight force signals IXI to NY2 of the corresponding one detection sensor. Based on IY2, 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 processing, and drive signals SX1 to SY2 are output based on the error signal.

As a result, the servo circuit 58 corrects the irradiation position of the light beam LAI 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 disposes a half mirror 69 on the optical path of the light beam LA1, 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 LR1 in parallel, and then passes the reflected light LR1 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 LAI at a low magnification, the magnification is sequentially increased and adjusted again, 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, corner cube prism 71 and half mirror
A shutter 75 is inserted between 69 and 69, and by opening and closing the shutter as necessary, the light beam L is
AI is prevented 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 SCI 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 half mirror 69
After the light beam LAI reflected by the corner cube prism 71 is turned back by the half mirror 69 and the mirror 5
7.56, the optical path to the light receiving element 64 via the lens 55, 54, polarizing prism 53, half mirror 62, and lens 63 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 can rotate as shown by arrow e around the optical axis of lens 59B. It is done like this.

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 1 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 housing 80 of the optical space transmission device main body 34, so that the windows 69A and 69 are fixed 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 shape of the sub-assembly becomes larger.

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 combined 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 8
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 storage 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. .

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-15) Servo circuit The servo circuit 58 operates the system control circuit 7 in response to the operation of the servo switch 39 and the initialize switch 37.
When the control signal SC2 is output from 7, it rises to the operating state.

As a result, the servo circuit 858 corrects the irradiation position of the light beam LAI 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 Wl 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 W1 of the light beam LAI 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.

! [181 rotates as shown by arrow g with respect to the main body of the transmission optical system 48 (that is, the optical system from the mirror 56 to the lens 59B) via bearings 81A and 81B arranged so as to surround the periphery. be held freely.

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 N185 drives the motor 86 based on the detection result, thereby moving the lens barrel 8 in a direction in which the amount of light incident on the position detection sensor 68 increases.
1, 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 LA1 and the polarization plane of the polarizing prism 53 are corrected so that the polarization plane W1 of the light beam LA1 and the polarization plane W1 of the light beam LAN are orthogonal to each other.

Therefore, even if the optical space transmission device main body 34 is installed at an angle, the plane of polarization can be automatically adjusted and the light beam LA2 can be efficiently incident on the light receiving element 64, and the adjustment work at the time of separate purchase can be avoided. 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 Y direction position detection circuit 86B. give,
Detect error signals VERX and VERY.

That is, as shown in FIG.
A is the output signal X1 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 output currents II and 12 changes.

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

Here, 1 represents a constant.

The Y-direction position detection circuit similarly performs addition/subtraction processing on the output signals IYI and IY2 of the position detection sensor 68, and generates a Y-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 12E, and the light beam LA
2 as I1 and I2, the output signal IXI
and IX2 is the following formula % formula % (2) Substituting this into formula (1), the following formula ERX (I 1 + IIE) + (12 + 12E)...
It can be expressed as (4), and it can be seen that it is sufficient to detect the output signals 11E and I2E of the position detection sensor 68 in a state where the light beam LA2 is not incident, and to subtract them from the output signals TXI 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 output voltages VEI and VB2 are detected.

Further, current-voltage conversion circuits 87A and 87B and subtraction circuit 8
8A and a subtraction circuit 90A between each power supply 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.

The light beam LA1 is emitted so that the light intensity is constant by driving the light beam using a 5Atic power control circuit.

Therefore, the intensity of the light beam LAI reflected by the transmission optical system 48 and incident on the position detection sensor 68 is equal to the intensity of the light beam LAI.
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 ■ERX and VERY based on the detection result. I can do it.

In this way, even when the transmission distance increases and the intensity of the light beam LA20 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 5B 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.
1 and SYI, and generates 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 displacement O 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 S02 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.
When the light intensity of the light beam LA2 decreases 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 position of the light beam LAI 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 quantity of the light beam LA2 returns to a predetermined value or more.

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 IXI 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 a wavelength of A2
7 is arranged.

The comparison surface 1197 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,
When the following formula % formula % (5), the servo signal output circuit 91! , - Outputs the comparison result, and thereby 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) Mirror Configuration As shown in FIG. 11, the 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 distribution 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 102 is constituted by a bimorph plate made of a piezoelectric element, and the tip thereof is displaceable according to the applied voltage as shown by the 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 SXI 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 LAX, 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) appears (Fig. 14 (A)
), and the phase changes by up to 1190 degrees (Fig. 14(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 [7].
(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 will not increase to 160 ()tz) as shown in FIG. Fig. 17 (A)), and the phase delay can also be reduced to 1130 degrees (Fig. 17 (A)).
B)).

Therefore, the frequency characteristics of the bimorph plate 1020 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, and the mirror 56 (
57).

In other words, 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 plate 102 and the displacement of the mirror 56 (57) is restricted.

Therefore, in the optical space transmission device 30, the bimorph plate 1
Predetermined route i1 from 02! Mirror 56 (5
7), 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 optical space transmission device 30.

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 initialize switch 37 is turned on in this state, the system control circuit 77 outputs a control signal SC1 to drive the motors 60 and 61, and sets the lens 59A to position 1, which is the center of rotation.

As a result, 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 LAN.

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 the magnification of the imaging optical system 70 is switched in response to the turned on operation of the zoom operator 42.

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 230 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, the system control circuit 77 determines that the servo is locked when the light beam LA2 is focused within a predetermined range on the light receiving surface of the position detection sensor 68 based on the error signals VERX and VERY of the servo circuit 58. Then, the light emitting element 40B is turned on.

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 LA1 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 60 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 LAI of the 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 passed through the lens 54.
and is reflected by mirrors 56 and 57 via lens 55.

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 SXI output from the servo circuit 58
The bimorph plate 102 (FIG. 11) is displaced by SY1 and SYl, 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, thereby making it possible to accurately detect the exit position of the light beam LA2 with respect to the optical space transmission device main body 34.

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 optical path of the light beam LAN is turned back in 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.

As a result, the light beam LA, 1 is transmitted through the imaging optical system 70.
The irradiation position can be confirmed.

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.

At this time, collimating scope A (Figures 3 and 4)
, is housed in a predetermined housing 78 and held so as to be able to rotate as shown by arrow e around the optical axis of the lens 59B, and the entire body is tilted in the diagonal direction of the housing 80 of the optical space transmission device main body 34. It is designed so that it can be maintained.

As a result, in the optical space transmission device main body 34, the rectangular internal space can be effectively utilized to house the collimating scope A, thereby making it possible to reduce the overall size.

Therefore, the overall weight of the optical space transmission device 30 can be reduced accordingly, and the usability can be improved.

(G3) Effects of Embodiment According to the above configuration, the collimating scope A is housed in the predetermined housing 78 and the entire body is tilted, thereby making effective use of the space inside the housing 80 and reducing the overall size. , and the usability of the optical space transmission device 30 can be improved accordingly.

(G4) Other Embodiments In the above-mentioned embodiments, a case has been described in which a corner cube prism is used to fold back the light beam LAX, but the present invention is not limited to the case where a corner cube prism is used, and the optical path is folded in parallel. Reflective members can be widely applied.

Further, in the above-described embodiment, a case has been described in which the collimating scope is housed in the housing 78 and arranged obliquely; however, the present invention is not limited to this, and the present invention is not limited to this.
It is also possible to arrange the lens barrel at an angle.

Furthermore, in the above-described embodiments, a case has been described in which the present invention is applied to a bidirectional optical space transmission device, but the present invention is not limited to this, but can be widely applied to a transmission-only optical space transmission device, etc. .

H Effects of the Invention As described above, according to the present invention, by arranging the optical path folding optical system, the optical branching means, and the observation optical system at an angle, it is possible to arrange the collimating scope by effectively utilizing the space inside the housing. 9. A small and lightweight optical space transmission device can be obtained.

[Brief explanation of drawings]

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 cross-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 frequency characteristics according to the embodiment, and FIG. 18 is a characteristic curve diagram showing frequency characteristics. A cross-sectional view showing the state of displacement of the bimorph plate,
FIG. 19 is a route map 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-110,71
...Corner cube prism, 70...
...Imaging optical system, 75...Shutter, 78.8
0...Housing.

Claims (1)

[Claims] By sending a transmission light beam modulated with a predetermined information signal to a reception device arranged a predetermined distance apart, the information signal is transmitted to the reception device via the transmission light beam. An optical space transmission device for transmitting the data includes: a light source that emits the transmitted light beam; and a light source that transmits the transmitted light beam emitted from the light source to the receiving device, and receives observation light arriving from around the receiving device. An optical system is inserted between the optical system and the light source, and reflects a part of the transmitted light beam obtained through the light source, and converts the observation light obtained through the optical system into the transmitted light beam. a light branching means for reflecting in the opposite direction to the beam; an optical path folding optical system for folding in parallel the optical path of the transmitted light beam or the observation light reflected by the light branching means; an observation optical system for observing the transmitted light beam or the observation light together with the observation light or the transmitted light beam reflected by the optical branching means, the light source, the optical system, the optical branching means, and the optical path folding optical system; The system and the observation optical system are housed in a rectangular housing, and the optical branching means, the optical path folding optical system, and the observation optical system are arranged on a diagonal line of the housing at a substantially right angle to the optical axis of the optical system. An optical space transmission device characterized in that it is arranged as follows.