JPH02276328A - Optical spatial transmission equipment - Google Patents

Abstract

PURPOSE:To miniaturize the optical system of an optical branching means, etc., and to surely detect the irradiation position of an optical beam by branching the optical beams converted to parallel light beams, sending them to a transmission object, and observing them simultaneously with observation light. CONSTITUTION:A half mirror 25 is interposed between lenses 21 and 22, and the optical beam LA1 is branched, and is reflected at an angle of around 90 deg.. Thereby, a reflected optical beam LA2 is introduced to a corner cubic prism 9. Therefore, a reflected optical beam LA3 whose optical axis is folded in parallel against the reflected optical beam LA2 can be obtained, and the reflected optical beam LA3 transmits the half mirror 25, then, is introduced to a lens 27. Consequently, it is possible to observe the image of a laser beam source 3 based on the reflected optical beam LA3 by displaying an image pickup signal obtained from an image pickup element 29 on a monitoring device.

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 (Fig. 8) D: Problem to be solved by the invention (Fig. 9) E: Means for solving the problem (Figs. 1 and 6) ) F action (Figures 1 and 6) G embodiment (Figures 1 to 7) (G1) First embodiment (Figure 1) (G2) Second embodiment (Figure 2) (G3) Third embodiment (Fig. 3) (G4) Fourth embodiment (Fig. 4) (G5) Fifth embodiment (Fig. 5) (G6) Sixth embodiment (Fig. 6) (G7) Seventh Embodiment (Figure 7) (G8) Other Embodiments A Industrial Application Field The present invention relates to an optical space transmission device, and is suitable for application to, for example, a bidirectional optical space transmission device. It is something.

B Summary of the Invention The present invention provides an optical space transmission device that converts a light beam or observation light sent to a transmission target into a parallel light beam, and then turns back the optical path and observes it together with the observation light or light beam, thereby reducing the overall size. The irradiation position of the light beam can be detected reliably.

At this time, in the first invention, the irradiation position of the light beam is reliably detected by converting the light beam and observation light into parallel light beams, and then bending the optical path and guiding them to the optical path folding optical system and the observation optical system. be able to.

Furthermore, in the second invention, after bending the optical path, the light beam or observation light is converted into parallel light beams and guided to the optical path folding optical system, thereby reliably detecting the irradiation position of the light beam with a simple configuration. I can do it.

C. Prior Art Conventionally, in this type of optical space transmission device, one has been proposed in which the irradiation position of the light beam can be easily detected on the transmitting side (Japanese Patent Application No. 123543/1983, Patent application No. 63-134230, patent application No. 63-123543
issue).

That is, in FIG. 8, 1 indicates the optical space transmission device as a whole, and a laser light source 3 that emits a light beam LA1 modulated with a predetermined information signal is arranged in a housing 2.

A large-diameter lens 4 is disposed in front of the laser light source 3, and is configured to convert the light beam LAI emitted from the laser light source 3 into parallel light beams and send them to a transmission target.

On the other hand, a collimating scope 6 is provided in front of the lens 4, so that the irradiation position of the light beam LA1 can be detected.

That is, the collimating scope 6 separates a part of the light beam LA1 by reflecting the light beam LAI at an angle of approximately 90 degrees on the half mirror surface 7A of the optical block 7, and corners the resulting reflected light beam LA2. It is designed to lead to a cube prism 9.

Therefore, a reflected light beam LA3 is obtained by folding the optical axis parallel to the reflected light beam LA2 through the corner cube prism 9, and the reflected light beam LA3 is reflected by the half mirror surface 7B of the optical block 7 and is telescoped. It is designed to be guided by 8.

Thus, in the telescope 8, the reflected light beam LA3
Based on this, the image of the laser light source 3 can be observed.

Furthermore, the collimating scope 6 has a window 10 on the front side of the telescope 8, so that the light LA4 arriving from the transmission target side (hereinafter referred to as observation light) is guided to the telescope 8 by passing through the half mirror surface 7B. There is.

This makes it possible to observe the transmission target side through the telescope 8 in addition to the image of the laser light source 3.

At this time, the light beam LAI is reflected by the half mirror surface 7A and the optical axis is turned back in parallel, so that the observation light LA4
, a component whose optical axis is parallel to the light beam LAI enters the telescope 8 in parallel to the reflected light beam LA3.

As a result, it is possible to obtain a reflected light beam LA3 that appears to have been emitted from the irradiation position of the light beam LAI, thereby making it possible to observe an image of the laser light source 3 placed at the irradiation position of the light beam LAI. .

Therefore, the irradiation position of the light beam LAI can be easily detected on the optical space transmission device 1 side via the telescope 8, thereby simplifying the installation work of the optical space transmission device 1.

D Problems to be Solved by the Invention By the way, in the optical space transmission device 1 having the configuration shown in FIG.
Based on the reflected light beam LA2 of a part of the light beam LAI determined by the size of the half mirror surface 7A, within the light beam LAIO of diameter DI emitted from the lens 4 to the spatial transmission path,
The irradiation position of the light beam LAI is observed.

Therefore, as shown in FIG. 9, if the half mirror surface 7A is mounted offset from the optical axis of the lens 4, the area actually irradiated with the light beam LAI will be affected by the reflected light beam LA2. There is a possibility that the observed irradiation position may be shifted.

Furthermore, even if the half mirror surface 7A is placed on the optical axis of the lens 4, there is a risk that an erroneous observation result may be obtained in which only a narrow area is irradiated compared to the area that is actually irradiated.

Therefore, in the optical space transmission device 1, the light beam LAI
There was still an insufficient problem in detecting the irradiation position reliably.

In order to solve this problem, a large optical block with a half mirror surface 7A can be used to create a reflected light beam LA2 from not only a part of the light beam LA1 but also the entire light beam LAI having a diameter DI. .

However, in this case, there is a problem that the structure of the collimator scope 6 becomes large due to the use of a large optical block, and the structure of the entire spectral space transmission device becomes large.

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 that is compact in size as a whole and is capable of reliably detecting the irradiation position of a light beam.

E Means for Solving the Problem In order to solve the problem, the first invention includes a light source 3 that emits a light beam LA1 modulated with a predetermined information signal, and a light source 3 that converts the light beam LAI into a parallel light beam. The first optical system 21 and the light beam LAI converted into parallel rays,
It is inserted between the transmission optical system 22.23 that sends out to the spatial transmission path, the first optical system 21 and the transmission optical system 22.23,
The light beam LAI converted into a parallel light beam is branched, and the observation light A4 is incident through the transmission optical system 22.23.
an optical path folding optical system 9 which folds in parallel the observation light LA4 reflected by the light branching means 25 or the optical path of the light beam LA2 branched by the light branching means 25; Light beam LA3 reflected by system 9
Or the observation light LA4 is reflected by the light branching means 25 or the light beam LA branched by the light branching means 25.
2 and observation optical systems 27 and 29 for observation.

Furthermore, in the second invention, a light source 3 that emits a light beam LAI modulated with a predetermined information signal;
A transmission optical system 23 that sends I to the spatial transmission path, and is inserted between the light source 3 and the transmission optical system 23 to branch the light beam LAI and reflect the observation light LA4 that enters through the transmission optical system 23. an optical system 71 that converts the observation light LA4 reflected by the light branching means 25 or the light beam LAI branched by the light branching means 25 into parallel light beams;
The optical path folding optical system 9 folds the optical path of a parallel light beam in parallel, and the light beam LAI or observation light LA4 that is folded back by the optical path folding optical system 9 is converted into the observation light L reflected by the light branching means 25.
An observation optical system 29 for observing the light beam LAI branched by A4 or the light branching means 25 is provided.

The F-action light beam LAI is converted into a parallel light beam and used as an observation light to be observed together with A4, and at this time, the light beam LA converted into a parallel light beam is
By sending I to the spatial transmission path, the irradiation position of the light beam LAI can be reliably detected even if the light branching means 25 and the optical path folding optical system 9 are downsized.

Therefore, the overall shape can be reduced and the irradiation position of the light beam LA1 can be detected reliably.

Further, at this time, if the light beam LAI or the observation light LA4 is converted into a parallel beam between the light branching means 25 and the optical path folding optical system 9, the light branching means 25 is arranged close to the light source 3, and the light beam LAI is irradiated. The position can be detected reliably.

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

(G1) First Embodiment In FIG. 1, in which parts corresponding to those in FIG. The beam LAI is converted by a lens 21 into a parallel light beam with a small luminous flux.

Further, lenses 22 and 23 are arranged on the optical path of the lens 21, and the light beam L converted into parallel light by the lens 21
The AI is converted into a luminous flux with a predetermined spread and size and sent to an optical space transmission path.

Thereby, on the transmission target side, it is possible to receive the light beam LA1 and demodulate the information signal from the light beam LAI.

On the other hand, there is a half mirror 2 between the lenses 21 and 22.
5 is inserted, and the light beam LAI is inserted in the half mirror 25.
The beam is branched and reflected at an angle of approximately 90 degrees.

Thereby, a part of the light beam LAI is branched from the entire luminous flux of the light beam LAI, and the resulting reflected light beam LA2 is guided to the corner cube prism 9.

Therefore, a reflected light beam LA3 is obtained by folding the optical axis parallel to the reflected light beam LA2 through the corner cube prism 9, and the reflected light beam LA3 is transmitted through the half mirror 25 and guided to the lens 27. is being done.

The imaging element 29 is arranged so that its imaging surface is on the focal plane of the lens 27, thereby condensing the reflected light beam LA3 to form an image of the laser light source 3 on the imaging surface.

Therefore, by displaying the imaging signal obtained from the imaging device 29 on a monitor device, the image of the laser light source 3 can be observed based on the reflected light beam LA3.

Furthermore, in the optical space transmission device 20, after the observation light LA4 arriving from the transmission target is reflected by the half mirror 25,
The image is formed on the imaging surface via the lens 27.

Therefore, on the display screen of the monitor device, the image of the laser light source 3 can be detected superimposed on the image of the transmission target.

At this time, by reflecting the light beam LAI by the half mirror 25 and turning back the optical axis in parallel, the observation light LA4
, a component whose optical axis is parallel to the light beam LAI enters the lens 27 in parallel to the reflected light beam LA3.

As a result, a reflected light beam LA3 that appears to have been emitted from the irradiation position of the light beam LAI can be obtained, and thereby an image of the laser light source 3 placed at the irradiation position of the light beam LAI can be observed.

At this time, in the optical space transmission bag R2o, after converting the light beam LAI into a parallel light beam with a small luminous flux, a half mirror 25 branches a part of the light beam LAI from the entire luminous flux of the light beam LAI to form a reflected light beam. Since LA3 was formed, using a small half mirror 25,
The irradiation position of the light beam LA1 can be detected reliably.

Therefore, the irradiation position of the light beam L A 1 can be reliably detected with a correspondingly smaller size.

Furthermore, not only the half mirror 25 but also the optical system including the corner cube prism 9 and the lens 27 can be downsized, and the entire spectral space transmission device 20 can be downsized.

Furthermore, since the entire device can be miniaturized, the entire device can be easily sealed and maintained, and thereby the weather resistance of the optical space transmission device 20 can be improved with a simple configuration.

Furthermore, since the half mirror 25 can be made smaller, the light beam LAI, which was unavoidable when the holding mechanism of the half mirror was conventionally placed in front of the lens 4 (Fig. 8),
vignetting can be effectively avoided, and thus the light beam LAI can be transmitted efficiently.

Incidentally, in this embodiment, the laser light source constitutes a light source that emits a light beam LAI modulated with a predetermined information signal, whereas the lens 21 constitutes a first optical system that converts the light beam LAI into parallel light beams. Configure.

Further, the lenses 22 and 23 constitute a transmission optical system that sends out the light beam LAI converted into parallel light beams to a spatial transmission path, whereas the half mirror 25 is inserted between the first optical system and the transmission optical system. A light branching means is configured to branch the light beam LAI converted into a parallel light beam and reflect the observation light LA4 incident through the transmission optical system.

Further, the corner cube prism 9 constitutes an optical path folding optical system that folds in parallel the optical path of the light beam LA2 branched by the optical branching means, and the lens 27 and the image sensor 29 fold the light beam LA3 which has been folded back by the optical path folding optical system. , constitutes an observation optical system that performs observation together with the observation light LA4 reflected by the light branching means.

According to the above configuration, the light beam L converted into parallel light beams
By branching the AI and sending it to the transmission target and observing the light beam together with the observation light, it is possible to downsize the optical system and reliably detect the irradiation position of the light beam LAI.

Therefore, the spectral space transmission device 20 can be downsized and the irradiation position of the light beam LAI can be reliably detected.

(G2) Second Embodiment In FIG. 2, in which parts corresponding to those in FIG. The light beam LAI
The irradiation position can be detected with the naked eye.

Thus, in this embodiment, lenses 27 and 33 constitute an observation optical system.

According to the configuration shown in FIG. 2, by providing the eyepiece 33 in place of the image pickup device 29, the irradiation position of the light beam LA1 can be detected with the naked eye, and the light beam LA1 can be reliably detected with a simple configuration as a subassembly. It is possible to obtain an optical space transmission device that can detect the irradiation position of.

(G3) Third Embodiment In the optical space transmission bag wt40 shown in FIG. 3, the half mirror 25 is arranged with the plane rotated by 90 degrees.

In this case, in the light beam LA1 converted into a parallel light beam, the component branched by the half mirror 25 is transmitted to the lens 27.
The light directly enters the image sensor 29 via the.

On the other hand, in observation light LA4, half mirror 2
After being reflected by the corner cube prism 9 , the light is reflected by the corner cube prism 9 and guided to the image sensor 29 via the lens 27 .

Therefore, similarly to the first embodiment, in the observation light LA4, a component whose optical axis is parallel to the light beam LAI enters the lens 27 in parallel to the light beam LAI split by the half mirror 25, and this component is parallel to the light beam LAI split by the half mirror 25. Accordingly, the irradiation position of the light beam LAI can be detected.

Thus, in this embodiment, the corner cube prism 9 constitutes an optical path folding optical system that folds in parallel the optical path of the observation light LA4 reflected by the half mirror 25, which is a light branching means, whereas the lens 27 and the image pickup device 29 constitutes an observation optical system that observes the observation light LA4 reflected by the optical path return optical system together with the light beam LAI branched by the light branching means.

According to the configuration shown in FIG.
Even if 4 is folded back, the same effect as in the first embodiment can be obtained.

(G4) Fourth Embodiment In FIG. 4, 50 indicates an optical space transmission device as a whole, and a half mirror 52 is inserted between the lens 22 and the half mirrors 2 and 5.

The half mirror 52 receives the light beam LBI sent out from the transmission target via the lenses 23 and 22, bends the optical path of the light beam LBI by 90 degrees, and then guides the light beam LBI to the photodetecting element 56 via the lens 54.

Thereby, the light beam LBI sent out from the transmission target is detected by the photodetection element 56, and the output signal of the photodetection element 56 is demodulated by a predetermined demodulation circuit, thereby detecting the information signal sent out from the transmission target. It is done like this.

Furthermore, at this time, in the observation light LA4, the half mirror
After passing through 52 and being bent by half mirror 25,
The reflected light beam from the corner cube prism 9 is guided to the image pickup device 29.

As a result, in the optical space transmission device 50, the light beam L
By checking the AI irradiation position, it is possible to reliably irradiate the transmission target with the light beam LA1.

Furthermore, in contrast to the light beam LAI, the light beam LBI sent out from the transmission target can be reliably received through the lens 23,
This makes it possible to reliably transmit desired information in both directions.

According to the configuration shown in FIG. 4, the light beam LBI from the transmission target
Even in the case of receiving light beams, the same effect as in the first embodiment can be obtained by converting the light beam LA1 and the observation light LA4 into parallel light beams and observing them at the same time.

(G5) Fifth Embodiment In FIG. 5, reference numeral 60 indicates an optical space transmission device as a whole, and the image pickup element 29 and light receiving element 56 are arranged interchangeably with respect to the optical space transmission device 50 shown in FIG.

That is, observation light L obtained through lenses 23 and 22
A4 is directly reflected by the half mirror 25 and guided to the image pickup device 29 via the lens 27.

Furthermore, the light beam LBI from the transmission target is transferred to the half mirror 2.
The light is received by a half mirror 52 through a lens 54 and guided to a light receiving element 56 through a lens 54.

As a result, the light beam LAI is converted into a parallel light beam by the lens 21, and then the half mirrors 52 and 25,
The signal is sent out to the transmission target via lenses 22 and 23 sequentially.

Furthermore, the light beam LAI is split by the half mirror 25, then turned back by the corner cube prism 9, and guided to the image sensor 29, thereby making it possible to detect the irradiation position of the light beam LAI.

According to the configuration shown in FIG. 5, the image sensor 29 and the light receiving element 56
The same effect as in the first embodiment can be obtained even if the elements are replaced and arranged.

(G6) Sixth Embodiment In FIG. 6, in which parts corresponding to those in FIG. 1 are given the same reference numerals, 70 indicates an optical space transmission device as a whole, and lenses 21, 22, and 27 are omitted. A lens 71 is arranged between the corner cube prism 9 and the half mirror 25.

That is, in the configuration shown in FIG. 1, the light beam LA1 is converted into a parallel light beam by the lens 21, and then is
The light is converted into a parallel light beam with a predetermined aperture and outputted through the lens 27, and is focused on the image sensor 29 by the lens 27.

That is, the light source 3 and the image sensor 29 each have a lens 2
It can be seen that they are arranged on the focal planes 1 and 27.

Therefore, instead of the lenses 21 and 27, a lens 71 is arranged between the corner cube prism 9 and the half mirror 25,
If the light source 3 and the image sensor 29 are placed on the focal plane of the lens 71, the light beam LAI converted into a parallel light beam can be incident on the corner cube prism 9, similarly to the embodiment shown in FIG. can. Further, an image of the light source 3 can be formed on the imaging surface of the image sensor 29.

Further, in the first embodiment, the lens 22 is omitted because the observation light LA4 is once focused by the lens 23, then converted into parallel light by the lens 22, and then focused by the lens 27 onto the image sensor 29. However, if the lens 23 is moved back and arranged so that the focal plane of the lens 23 becomes the imaging surface of the image sensor 29, the observation light LA4 can be focused on the imaging surface.

Furthermore, in this case, since the imaging surface of the imaging element 29 is located on the focal plane of the lenses 71 and 23, the light beam LAI is converted into a parallel ray and sent out as in the first embodiment. I understand that.

On the other hand, in the corner cube prism 9, the light beam LA1 split by the half mirror 25 is transferred to the lens 71.
The light beam LA
Reflected light beam LA3 emitted from the irradiation position of I
can be obtained.

Therefore, even if the lenses 21, 22, and 27 are omitted and the lens 71 is inserted between the corner cube prism 9 and the half mirror 25 to convert the light beam LA1 into parallel light, the irradiation of the light beam LAI The position can be observed on the transmitting side.

Furthermore, at this time, in the half mirror 25, the lens 7
As long as the light source 3 and the image sensor 29 are respectively arranged on one focal plane, the arrangement positions can be freely selected.

Therefore, by arranging the half mirror 25 close to the light source 3, the irradiation position can be accurately confirmed using the small half mirror 25, the lens 71, and the corner cube prism 9.

Therefore, the irradiation position of the light beam LAI can be reliably detected with a smaller overall size.

Furthermore, since lenses 21, 22, and 27 are omitted at this time,
The overall shape can be further reduced in size compared to the first embodiment.

According to the configuration shown in FIG. 6, a lens 71 is disposed between the corner cube prism 9 and the half mirror 25, and the lens 71 converts the light beam LAI into a parallel light beam, which is more effective than the first embodiment. Furthermore, it is possible to obtain an optical space transmission device that is compact and capable of reliably detecting the irradiation position of the light beam LAI.

(G7) Seventh Embodiment In FIG. 7, in which parts corresponding to FIG. Detect beam LBI.

In this case, in the light receiving element 56, the light receiving element 56 and the image pickup element 29 are arranged on the focal plane of the lens 52, that is, in a conjugate relationship with respect to the lens 23, and thereby the light beam LA1 can be irradiated with a simple configuration. In addition to confirming the location, it is possible to transmit desired information in both directions.

According to the configuration shown in FIG. 6, the light beam LBI from the transmission target
Even when receiving light, the corner cube prism 9
By arranging a lens 71 between the half mirror 25 and the half mirror 25, and converting the light beam LAI into a parallel beam using the lens 71, the same effect as in the sixth embodiment can be obtained.

(G8) Other Embodiments In the above-mentioned embodiments, a case was described in which a half mirror was used as the light branching means, but the light branching means is not limited to this. For example, infrared light or near-infrared light from a laser light source When emitting a light beam, a mirror having wavelength selectivity (that is, a cold mirror or the like) may be used.

In this way, the light beam can be efficiently transmitted to the transmission target and a bright image of the transmission target can be obtained.

In addition, the light beam LAI returned to the laser light source 3
The amount of light can also be reduced, making it possible to perform high-quality communications.

Further, in the first to fifth embodiments described above, the case where two convex lenses are used as the transmission optical system is described, but the present invention is not limited to this, and for example, a concave lens and a convex lens may be combined.

In this way, the distance between the lenses can be shortened, and the shape of the optical space transmission device can be further miniaturized.

Further, in the above-described embodiments, a case was described in which a laser light source was used to send out the light beam LAI, but the present invention is not limited to this, and can be widely applied to cases where a light source such as a light emitting diode is used, for example. .

Further, in the fourth to seventh embodiments described above, the case where the light beam LA1 is folded back by the corner cube prism 9 has been described, but in the present invention, instead of this, the observation light LA4 is folded back by the corner cube prism 9. Good too.

Furthermore, in the above-mentioned fourth to seventh embodiments, the case where the irradiation position of the light beam LAI is confirmed using an image sensor is described, but the present invention is not limited to this, and the present invention is not limited to this. You may also do so.

Further, in the above-described embodiment, a case has been described in which the light beam LAI branched by the half mirror 25 is inputted to the corner cube prism 9 directly or via the lens 71, but the present invention is not limited to this, and for example, an ND filter, etc. The transmitted light quantity limiting means is arranged to control the light beam L at a desired brightness.
The irradiation position of AI may be observed.

Furthermore, in the above embodiment, the case where the present invention was applied to a bidirectional optical space transmission device was described, but the present invention is not limited to a bidirectional optical space transmission device, but can be widely applied to various optical space transmission devices. can do.

Effects of the Invention H As described above, according to the first invention, the optical system such as the optical branching means can be split by branching the light beam converted into parallel light beams, sending them to the transmission target, and simultaneously observing the observation light. It is possible to reliably detect the irradiation position of the light beam by downsizing the irradiation position of the light beam, thereby making it possible to obtain an optical space transmission device that can reliably detect the irradiation position of the light beam with a miniaturized shape.

Furthermore, according to the second invention, by converting the light beam or observation light into parallel light beams between the light branching means and the optical path folding optical system, the overall shape can be reduced and the irradiation position of the light beam can be reliably detected. It is possible to obtain an optical space transmission device that can perform the following.

Figure 9 is a route map used to explain the problem.

1.20.30.40.50.60.70.80...
... Optical space transmission device, 3 ... Laser light source, 4
．． 21.22.23.27.33.54.71...
・・Lens, 9・・・Corner cube prism, 2
5.52,・・・half mirror

Claims (2)

[Claims] (1) a light source that emits a light beam modulated with a predetermined information signal; a first optical system that converts the light beam into a parallel light beam; and a first optical system that converts the light beam into a parallel light beam; a transmission optical system for sending out, and interposed between the first optical system and the transmission optical system,
While branching the light beam converted into the parallel light beam,
an optical branching means for reflecting the observation light incident through the transmission optical system; and an optical path folding optical system for folding in parallel the optical path of the observation light reflected by the optical branching means or the light beam branched by the optical branching means. and an observation optical system for observing the light beam or observation light reflected by the optical path folding optical system together with the observation light reflected by the light branching means or the light beam branched by the light branching means. An optical space transmission device characterized by: (2) a light source that emits a light beam modulated with a predetermined information signal; a transmission optical system that sends out the light beam to a spatial transmission path; a light branching means for branching the beam and reflecting the observation light incident through the transmission optical system; and a light branching means for splitting the beam and reflecting the observation light incident through the transmission optical system, and converting the observation light reflected by the light branching means or the light beam branched by the light branching means into parallel light beams. an optical path converting optical system for converting the optical path of the parallel light beam, an optical path folding optical system for folding the optical path of the parallel light beam in parallel; An optical space transmission device characterized by comprising an observation optical system that observes a light beam branched by a light branching means.