JPS5981936A - Optical data link - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

TECHNICAL FIELD OF THE INVENTION This invention relates to fiber optic data links, and more particularly to free space optical data links.

[Technical background of the invention]

Admittedly, free-space optical data links are used in line or fiber optic installations that are prohibited or inappropriate. Typical examples are rapid connections between two locations separated by the crossing of a river or wide estuary or major road complexes, or raised areas, or where the location of the link end station needs to change very frequently. such as major private projects where intervening areas are continuously excavated.

The link end stations of a typical free-space optical link include an electronic device for converting the electrical signal to be transmitted into an all-optical signal, an electronic device for converting the received optical signal into a corresponding electrical signal, and one end in line of sight. It is equipped with an optical system for emitting an optical signal 'Jt transmitted from one terminal station to another terminal station, and for receiving an optical signal 'Jt transmitted from the other terminal station to one terminal station. Generally, a link terminal station located on the roof of a building, for example, is equipped with both an optical system including a laser and a photodetector, and an electronic system, and is therefore very susceptible to temperature changes. This is of course a major drawback. This is because it impairs the characteristics of the optical link.

[Summary of the invention]

The general object of the invention is therefore to obviate the drawbacks of the prior art.

To explain in more detail, t2e f1' of this invention:
J's objective is to provide an optical link without the drawbacks of ordinary optical links.

Another object of the invention is to provide an optical link of this type that is substantially immune to weather and other environmental influences.

A further object of the invention is to construct an optical link of the type described above in such a way that it can be manufactured quickly and inexpensively, is easy to use, and is reliable in operation.

In order to accomplish these objects and other objects which will become clear from the following discussion, one of the features of the present invention is to provide a pair of aligned optical heads separated by an inter-optical optical data link. each optical head is provided with a respective optical fiber in a free space optical data link in which data is transmitted in the form of light in at least a first direction along an optical path between the heads, each optical head having a lens and an optical fiber. 1
means for attaching the end to the focal point of the lens, in use the data signal to be transmitted along the optical path is supplied in the form of light to one optical head via the respective optical fiber, and the corresponding data signal to the other optical head. The other end of the optical fiber that cooperates with the optical head is configured to be obtained in the form of light.

According to another aspect of the invention, there is provided an optical fiber, an optical head body having a through hole, a single lens element attached to one end of the through hole, and an optical fiber having an optical film freely attached to the other end of the hole. An optical head arrangement is provided, complete with support structure means for mounting the optical fiber, and in which the optical fiber is mounted, one end of the optical fiber being located at the focal point of the lens.

According to another aspect of the invention, a pair of aligned optical heads are provided separated by a free space data transmission path capable of transmitting data in the form of light in at least a first direction, each optical head including a lens and a means for placing one end of the optical fiber at the focal point of the lens, the data to be transmitted being converted into optical form by a transmitting optical-to-electrical converter applied to the other end of one optical fiber; The optical signal received at one end of the optical fiber is converted into electrical form by the other optical, receiving optical-to-electrical converter located at the other end of the fiber, the receiving converter being proportional to the received signal amplitude. obtain an output of and feed this output to a variable frequency oscillator to obtain a corresponding audio frequency variable tone;
/ A method for adjusting an optical-to-electrical converter in a free-space optical data link system in which all audio frequencies are transmitted to a transmitting converter via a link, and the transmitting converter is WM tuned to have a maximum tone pitch corresponding to a maximum signal amplitude. provided.

Therefore, in the optical data link of this invention, each link terminal is basically an active element. The optical head does not include an optical head, and input and/or output optical signals are input to and output from the optical head through a conventional optical fiber. The optical head may have a single optical path, and therefore only be capable of receiving or transmitting optical signals. Alternatively, it may have a single optically divided hole for transmitting and receiving optical signals,
Alternatively, it may have two optical paths with physically separated parallel holes (binoculars), one used for transmission and the other for reception. The electronic system that converts electrical signals to optical signals and vice versa can be located remote from the optical head. It is placed, for example, in the building to be linked; - the optical head is connected to this electronic system by means of an optical fiber;

In order to radiate an optical data signal from one optical head to another in free space, the output end of the optical fiber is placed at the focus of a simple positive lens that constitutes the transmission optics of the optical head, and hence its The image is projected onto the receiving optics of a remote optical head. The basic design requirements for the lens are that it must have a hole large enough to capture most of the cone-shaped rays emitted from the optical fiber, and that its focal length must be suitable for remote imaging of an appropriate size. It must be something that projects. Typically, for an optical fiber with a core diameter of 50 microns and NA=2,
Qmm, a lens with a focal length of 120F-1,m can be used.

To align the two optical heads'frR first.

Each head may be mounted on the support in an adjustable manner and each include a telescopic finder, the sight of which is fixed relative to the axis of the head body, or alternatively, especially if the transmitting and receiving optics are separate. First, either of these devices is converted into a telescope by replacing an optical fiber adapter, whereby the end of the optical fiber is placed at the focus of a simple convex lens by means of an eyepiece. Critical alignment is performed by the machines and means described in detail below.

The above-mentioned and other features and objects of the present invention will become more apparent from the following description with reference to the accompanying drawings.

[Embodiments of the invention]

Referring to FIG. 1, in one embodiment of the optical device of the present invention, the optical head includes a single optical path. Such an apparatus is shown in FIG. 1, in which the means for adjusting the optical path position in two directions mutually perpendicular to the fixed axis for critical or fine alignment are schematically illustrated. .

For example, a hole 2 is provided that penetrates the main body 1 of the optical head made of duralumin. The hole 2 serves as a stop for either the receiving or transmitting optical path, or may be optically divided as described later.

An objective lens 3 is fixed and held at the front end of the hole 2 (on the left side in the figure).

Fiber optic 4d elements 7 and 8 with polished end faces
, is mounted in a spring-loaded fiber connector 5 that includes a spring 15.

The connector 5 is screwed into the hole at one end of the fiber focus socket 6 until the optical fiber 4 comes into contact with the end face of a pot-shaped member 10 having a hole constituting a fiber position pointing device. It is screwed into a screw hole 9 at the other end of the focus socket 6. A fine thread is cut on the outer periphery of the socket 6 in the vertical direction.

The thread cooperates with a matching thread on one end of the fiber optic adapter and filter mount 12. Filter 13I171: Installed in the mount 12 at the position shown.

The purpose of such filters is to reduce the possibility of interference from interfering broadband light sources such as the sun. The filter 13 used is a narrow bandpass filter tuned to the wavelength of the transmitted light 1] and is placed in the receiving optical path. There is no need to place a similar filter in the transmission optical path.

The mount 12 is threadedly engaged with a corresponding screw on the body 1. A ring seal 12' may be placed in the groove of the filter mount 12 to prevent dust and water vapor from entering into the bore 2 and into the inner surface of the lens 3.

The parallel light beam incident from the left side is the polished m of fiber 4.
! The lens 3 is adjusted during manufacture so as to focus on the object. Adjustments for this purpose are made by screws in the socket 6 and the mount 12. Once the correct adjustment is obtained, the socket 6) is locked into position by the lock song 14. Since the lenses used for a given pair of optical heads for a data link are the same, and the distance between the lenses and the fibers is also the same, ii,; This may be done by completely avoiding the need to provide sufficient means when the beams emitted from the left side of the beam source or lens 3 are parallel.

The main body 1 is attached to a support plate 16 that is attached to a tripod or other support stand (not shown) via a tilt (pan/tilt) block 16af that performs coarse adjustment of the aim of the optical head. ing.

For this coarse adjustment, the fiber optic adapter and filter mount 12 are unscrewed as a unit from the body 1 and replaced by the eyepiece to form the telescope. The main body 1 is attached to a support plate 16 via a universal joint 17, and 17 is a vertical (aiming) corner hinge ()+ing.
e) Consisting of 17a and azimuth hinge 17b. Fine adjustment of the vertical angle and orientation is performed by a pin 18 having a fine screw that engages with a fine screw hole in the main body J.
The tip of the worm gear 19 is connected to the groove around the worm gear 19, and the worm gear 1'QJ can be rotated around the worm gear 19a. Therefore, by rotating the bottle 18 into and out of the hole to change its effective length, the vertical angle of the optical head is adjusted, and by rotating the worm gear 19, the orientation of the optical head is adjusted. Once set during use, the correct position is determined by the spring-loaded locking rod 20 between the plate gouge and the head body 1.
held by. When fine-tuning is performed in this manner, the pre-focused fiber adapter and fiber mount 12 are fixed in position within the body of the head, co-located with the head but separate from it. The electronics are adjusted for maximum signal amplitude as described below with reference to FIG.

The 2nd M is the lens 2 of the optical path of the button link.

22 and the optical fibers 23 and 24 are schematically shown in [11]. The optical signal to be transmitted in the 1nons 21, 22fpf3 is generated by an electromagnetic converter consisting of a pulse frequency modulation transmitter 25 containing a light beam source, such as a semiconductor laser. )Y; The signal is generated from the output signal at 7 which appears at terminal 26 and is supplied to transmitter 25. At the other end of the optical data link, the incoming optical signal is routed to terminal 27.
The signal is then converted into an electrical output signal by an electrical converter consisting of a pulse frequency modulation receiver 28 that includes a photodetector such as a photodiode. The electronics associated with the optical head are tuned to work best under good atmospheric and other operating conditions, and therefore under poor atmospheric and other operating conditions, such as fog, for example.
It is desirable that the transmitted signal can still be well received when the operating conditions are relevant. For this purpose, it is necessary to have means for measuring the signal received by each optical head and to adjust both the transmitting and receiving electronics for maximum signal amplitude. At the receiver, this is accomplished by monitoring the meter and simply adjusting the receiver to the line of sight of maximum signal amplitude. However, at the transmitter Cj
``When making adjustments to the transmitter, it is necessary to know exactly what conditions are occurring at the receiver. This is done by taking the output 29 of the receiver 2B from a position such as a photodetector, e.g. a photodiode, in the receiver whose output is related (proportional) to the amplitude of the signal. This output then has a variable frequency (pitch)
The oscillator 30 is fed to the oscillator 9, which converts it into a variable tone output at the loudspeaker 3. This variable tone output is then routed to the audio frequency link 32 to the transmitting end of the optical link.
, for example, by telephone line or walkie-talkie radio. Therefore, the person at the transmitting end can "shape" the shadow of the transmitting end electronics for the transmitting optical head in the electronic device cooperating with the receiving optical head,
The electronics for the transmit optical head can be easily adjusted to obtain maximum transmit amplitude at the receiver. A variable frequency (pitch) oscillator can be constructed by any oscillator that responds to changes in voltage or current output from a receiver, and that oscillator changes its amplitude with its signal level when the current or voltage changes. and hence the pitch level changes.

Optical links are preferably transmitted over the visible part of the spectrum, which is useful for many possible applications; audio to audio or data can also be transmitted by them, and up to 8 megabits in binary format. It is also possible to send data such as The bandwidth that can be transmitted is limited only by the bandwidth of the electronic device. Basically, at a carrier wavelength of 1 micron, the bandwidth can be 20×10H>;

1. In the case of a binocular arrangement of the incoming and receiving optical paths, each head may be provided with a telescopic finder with an identified derailment relative to the axis of the head body 1 in order to perform the initial alignment of the optical heads. .71 Means must be provided for adjustment to obtain tight parallelism between the viewfinder and the transmitting and receiving optical paths, to accommodate mechanical tolerances and focus errors among the It is also necessary to perform 11.:1 heating point adjustment of each )'0 fiber for each lens.

This is the outfit shown in Figure 3! It is done by E.

That's how ICL line focuses 4! ! A high I/C position is used for each of the transmit and receive optical paths.

However, only one of them is shown in the diagram.

For example, three parallel holes are provided in the duralumin body 40, only one of which is shown at No. 4. The hole 4 may be used for either a receiving optical path or a transmitting optical path. Similar holes are provided for the remaining optical paths, while a third hole is provided for the finder. At the front end of the six-hole 41 (left hand in the figure) a valley objective lens such as 42 is held in a fixed mount.

An optical fiber 43 with a polished end face is pushed into an adapter 44 provided at the rear end of a W1 focusing tube 45, and the focusing tube 45 is connected to its shoulder 47 and to the main body 4.
It is biased toward the objective lens 42 by a compression spring 46 coupled between a rear end plate 48 fixed at zero.

A front end plate 49 is secured to the opposite end of the body 40. A focus nut 50 coupled to a fine thread at the end of the focus tube 45 acts to move the spring loaded focus tube 45 axially, thus placing it on the two lens fittings as described above. Move the end of the optical fiber to the precise focal position determined by.

The filter is mounted on a filter mount 51 in the focus tube 45.
Can be installed inside. The purpose of such a filter is to minimize the possibility of interference from interfering broadband light sources such as the sun. The filter used in mount 51 is a narrow bandpass filter placed in the receive optical path and tuned to the transmit wavelength. It is not necessary to include a similar filter throughout the transmitting optical path.

A guide groove 53 is provided in the extension 52 of the focus tube 45, which is provided with a shoulder 47 for spring support. This guide groove 53 is connected to a pin 54.

The pin 54 is fixed to the main body 40 and allows the focus tube 45 to move back and forth while preventing rotation.

The focus tube 45 is slidably fitted into a cylindrical bore 55 of an outwardly inclined adjustment element 56. The axis of the hole 55 is, for example, Q, 5 mm in this preferred binocular optical head.
The conical sloping outer surface of the adjustment element is offset with respect to the central axis. The beveled outer surface of the adjustment element 56 is encased in and held within the inner bevel of an adjustment element 57, which also has an external bevel. The internal and external ramps of the adjustment element 57 also have an off-axis lattice of Q, 5 mm in the cited example. The outer slope of the adjustment element 57 is connected to the rear end plate 48.
It is enclosed in and retained by a tilted hole 58 therein.

Hole 58 is drilled so that it is nominally coaxial with the optical axis of objective lens 42. Each ramp and nut 50 and element 56 are held in tight connection by a spring 4G. The angle of inclination is such that by the inclusion of a high viscosity lubricant, a smooth and precise rotation of the adjusting element can take place without restriction. In the typical old model, the angle of inclination is 30°. In order to perform critical adjustment, the focus nut 50 and adjustment elements 56 and 57 are equipped with Tommy
Tommy-bor holes may also be provided.

In this way, if the adjustment elements 56 and 57 are oriented to exactly cancel the offset of their axes (Q, 57rLm) 7M, the ends of the optical fibers will be positioned so that it is on an axis close to .

However, if adjustment elements 56 and 57 are rotated independently, the optical fiber is free to be displaced in either direction by up to 1 mnt in this embodiment to compensate for alignment errors.

When using an optical data link system, it is also necessary to accurately align the terminals (optical heads) 'f on the two sides.

For this purpose, a new concentric eccentric ramp ridge cone system is used as described above. An optical head consisting of a main body 40 and end plates 4B and 49 is attached to a pan/tilt block 59. The front end plate 49 is secured to the block 59 via a flat phosphor bronze spring 60 which provides a high degree of stiffness while allowing the JOI curve to deflect the rear of the head a small distance in any direction. I'm trying to make it possible. Between the rear end plate 48 and the block 59 a pair of new concentric tilt adjustment elements 6 and 62 are arranged, which operate as described above for the adjustment elements 56 and 57, the movement of which is e.g. 61 and a socket 64 provided in the block 59.
"l't- to block 59.

The pressure on the steel ball 63 is maintained by a moderate pre-pressure provided by a phosphor bronze spring 60. Moshi adjustment elements 61 and 6
If the axes of the two inclined parts are offset in inn, it is possible to obtain a total of two degrees of movement in either direction.A Adjustment elements 6 and 62 facilitate operation for adjustment. For example, a Tommy hole (not shown) may be provided. The pan/tilt block 59 is generally attached to a tripod or other support (not shown) via means that allow coarse adjustment of the aiming of the optical head, and adjustment elements 61 and 62 are used to adjust the final criticality of the aiming. Used only for NJ'l adjustment.

When good visual alignment is impractical, percent alignment may be achieved using adjustment elements 61, 62 with a variable pitch oscillator as described with reference to FIG. However, the blind adjustment is the new open heart adjustment element 61.6
It is easier to use the vertical angle and azimuth fine adjustment device described in FIG. 1 than 2. This is because with the newly opened heart adjustment element, it is difficult to judge which adjustment element vi should be adjusted and in which direction. Therefore, an embodiment may be considered in which the helad mount shown in FIG. 3 is replaced with the helad mount shown in FIG. 1.

The adjustment elements 56, 57 and the pulleys 50 are normally adjusted to the correct setting during the manufacture of the optical head, and only adjustment of the pan/tilt block is required during use. The use of conical bearing surfaces of various slopes acts to eliminate slope and backlash. However, it is not essential that the surface be conical.

Although the single optical path device described above generally uses all circular lenses, other lenses may be used instead. For example, a single lens may be split into two halves by placing a low power wedge prism in front of the half of the lens, eg the receiving half. The prism produces separated receive and transmit images, and the separation is fixed by the angle of the prism so it is very stable. In this device, both the transmitting and receiving optical paths pass through the same telescope barrel. That is, the same holes in the optic-rad body are matched to greatly simplify alignment, adjustment, and stabilization problems. However, the splitting of the lens in this method halves the transmitting and receiving areas, resulting in corresponding optical losses compared to a binocular device with two optical paths each having the same dimensions as one lens with a single optical path. arise. However, this can be compensated for by using a larger lens that accommodates the splitting device. Another possible optical arrangement is to use a circular lens in the central part of a single lens for transmitting and a ring lens consisting of a surrounding part for receiving.

Compared to wireless links and conventional free-space optical link designs, the system of the present invention has a remarkable ability to wander through very narrow beam angles on the order of 0.05° without having to rely on very large and expensive optics. It has an effect. A narrow transmit beam has the effect of minimizing total optical path loss and greatly reducing the possibility of interference by unauthorized persons, while an equally narrow receive visibility minimizes total optical path loss and reduces the possibility of interference by unauthorized persons, while an equally narrow receive visibility minimizes total optical path loss and reduces the likelihood of interference by unauthorized persons. Reduces the risk of noise and interference from light sources.

The light source head contains no active parts. Input and output signals are propagated in the form of light through optical fibers. Free space systems are therefore compatible with current or future developments in fiber optic transmission or reception. System range (ra)
The limit of ng(!) depends on the power of the optical transmitter and the sensitivity of the optical receiver used with it. The clothing of the world [h
The range of the order of gilometers is i′3.

The projection system may use a simple single-element lens rather than the more expensive type with correction for normal lens convergence. The monochromatic nature of the optical fiber eliminates the need for correction of chromatic aberrations, and the very small diameter of the optical fiber end prevents off-axis errors such as astigmatism and curvature of the field of view. This is because point light sources on the axis that are not applied can be treated as C. Spherical aberration can also be minimized by appropriately selecting the relative curvatures of the two lens surfaces.

Although the principle of this invention has been explained above in connection with a specific device, this explanation is merely an example, and does not limit the technical scope v+1 of the invention described in the claims. You should clearly understand that monodaba 7 is good.

[Brief explanation of the drawing]

FIG. 1 is a schematic partially folded view of an optical head used in an optical data link according to an embodiment of the present invention, FIG. 2 is a schematic diagram of an optical data ring, and FIG. The diagram is 2
Individual light 11! ,! All optical fibers, 5... Connector, 6... Force socket, 12... Filter mount, 13°... Filter. 21.22...Objective lens, 23.24...Original fiber, 25...Transmitter, 28...Receiver 1, 30.
...Divergent, 31...Speaker, 32...-6 frequency link, 40...Main body, 42...Objective lens,
43... Optical fiber, 45... Focus tube, 56
．． 57...i school opening element.

Claims (1)

Claims: (1) a pair of aligned optical heads separated by a free space data transmission path operative to transmit optical information signals in at least one direction along an optical path between the optical heads; and each optical head; 17f between the position away from the optical head and the optical head.
at least one optical fiber provided to each optical head for transmitting an optical information signal at a lens, each optical head having one end of each optical fiber at the focal point of the lens. support means for mounting, wherein in use an optical information signal to be transmitted along the optical path is supplied to said optical head via the optical fiber of the respective head, and a corresponding optical information signal is provided with respect to the other optical head. A free-space optical data link, characterized in that Ml is provided at the other end of the optical fiber at said location remote therefrom. (2) Light at the other end of the optical fiber. An electrical converter is provided for converting the information signal supplied to the system in electrical form into an optical information signal for transmission through the optical fiber and for transmitting the received optical information signal from the system to the next. 4. An optical data link as claimed in claim 3, characterized in that the optical data link can be converted into an electrical form at any time. (3) Each optical head is provided with an optical fiber,
The system is designed to transmit optical information signals in both directions along an optical path between optical heads. (4) The optical data link of claim 3, wherein the optical head comprises a respective lens for each optical fiber, the two lenses of each optical head being arranged in a binocular configuration. (5) Each optical head comprises a single lens and a 7° rhythm that is respectively placed adjacent to each lens and operates to divide the optical path between the heads into a full receive and transmit portion, thereby providing optical information. 4. An optical data link according to claim 3, wherein the optical data link is constructed so that signals can be transmitted in both directions. (6) A support means for attaching one end of the optical fiber is provided with a main body, an optical fiber adapter and a filter mount for each fiber, and the adapter and filter mount are attached to the main body so as to be replaceable with an eyepiece. It is configured to be removably attached, thereby converting the optical head into a telescope for alignment of the optical head, and when the adapter and filter mount are again fixed to the main body, one end of the optical fiber is automatically brought to the focal point of the lens. An optical data link according to claim 1, wherein the optical data link is arranged such that the optical data link is located at a central location. The optical head comprises a main body and an adjustable mounting means for aligning the two optical heads attached to the main body,
2. An optical data link as claimed in claim 1, wherein said adjustable mounting means includes means for coarse and fine adjustment. (8) The fine adjustment means includes a support plate to which one end of the optical head body is attached via a universal joint, and a fine adjustment means that is rotatable to the support plate in close proximity to the opposite end of the optical head body. a worm gear attached to the optical head body, and a pin having an adjustable effective length attached to the optical head body and coupled to the worm gear, whereby rotation of the worm gear adjusts the azimuth position of the optical head; 8. The optical data link according to claim 7, wherein the length of the bin is adjusted to fully adjust the vertical and angular positions of the optical head. (9) The optical data link according to claim 2, wherein the transmitting optical-to-electrical converter comprises a pulse frequency modulation transmitter, and the receiving optical-to-electrical converter comprises a pulse frequency modulation receiver. α0) comprising a variable frequency oscillator and a loudspeaker, the Nofrus frequency modulation receiver provides the oscillator with an output proportional to the amplitude of the received signal, and the output of the oscillator is fed to the loudspeaker, thereby transmitting the optical head by means of an audio frequency link. 10. The optical data link of claim 9, wherein the optical data link is constructed to provide a variable tone output for adjusting the transmitter to transmit a maximum transmitted signal to a pinch trap. al) each optical head comprises coarse and fine adjustment means for aligning the two optical heads, the fine adjustment means comprising a tube at one end of which an end of an optical fiber is attached;
This tube Fi is slidably mounted in the cylindrical bore of the first adjustment element, which is nested in the second adjustment element tt, 17j, and the second adjustment element is inserted into the optical head body. nested within a correspondingly shaped bore, the first and second adjustment elements being sleeve-like, the first adjustment element having an outer surface having an axis parallel to, but offset from, the axis of the cylindrical bore; , the axes of the inner and outer surfaces of the second adjustment element are parallel to each other but offset, such that the position of the core tube relative to the main body is different from that of either or both of the first and second adjustment elements relative to the main body. The optical data link according to claim 1, which is configured to be adjustable by rotation. 0) The inner and outer surfaces of the first and second adjustment elements are in the shape of a circle 41), relative to the body I1. 12. A source data link as claimed in claim 11, further comprising means for preventing inadvertent rotation of the tube. 03) In order to bring the axial position of the tube and therefore the optical fiber into focus, there is provided a means for adjusting RL'1 phantom to a lens. Optical data link. A spring is provided for applying a force to bias the tube relative to the body, and the shaft is urged adjacent to one end into engagement with a first adjustment element under the action of the spring. An adjustable stop t4"Th is supported, and the M ring is located between the 7+\ portion of the tube provided near the other end of the tube and the surface of the body surrounding the hole. ;'l
- An optical data link according to item 11ζ of claim 13. (I) An optical fiber, an optical to rad body with a through hole, a single lens element attached to one end of the four-hole, and an optical fiber detachably attached to the other end of the general-purpose hole. supporting means for supporting one of the optical fibers in the mounting position;
1, characterized in that the end is located at the focal point of the lens
Optical head device for single-mount spatial optical data link (16)
Means for the support means to fully support the optical filter in the optical path between the lens and one end of the optical fiber? An optical head device according to claim 15. 16. The optical head device according to claim 15, comprising adjustable mounting means for fully aligning two optical head mountings, said adjustable mounting means comprising means for coarse and fine adjustment. The main body is attached to a support plate through a fine adjustment means. One end of the body has a universal joint and a worm gear attached to the support plate, and a length-adjustable pin, through which the other end of the body is attached to the support plate, and the worm gear is Support: The F! is rotatably supported. The bottle is attached to the main body [), so that the rotation of the Warno gear adjusts the azimuth position of the optical head Mlj, and the adjustment of the length of the bottle l adjusts the azimuth position of the optical head. Adjustment of vertical angle, effect? The optical head device according to claim 17, which is comprised of: 14. The optical head device comprises a main body which is attached to a support plate with a coarse adjustment means, and the fine adjustment means is used to adjust the main body to the main body through the fine adjustment means. An optical fiber is attached to one end of the attached tube, the fine adjustment means comprises a pair of nested adjustment elements, said tube is slidably disposed in the bore of the adjustment element of z131, and the fine adjustment means comprises a pair of nested adjustment elements; The outer surface of the first adjusting element, the inner and outer surfaces of the second adjusting element are conical, and the outer surface of the second adjusting element is nested in the corresponding hole of the body to insert the flap 1 into the opening. The longitudinal axes of the cylindrical bore and the outer surface of the adjusting element and the inner and outer surfaces of the second adjusting element are parallel to each other but offset from each other, so that the first and second adjusting elements 18. The optical-to-radical device according to claim 17, wherein the rotation of the tube adjusts the position of the tube relative to the main body. comprising a pair of aligned optical heads separated by a free-space data transmission path capable of transmitting data, each optical head comprising a lens and means for placing one end of a respective source fiber at the focal point of the lens; power data t; (converted from electrical form to optical form by a transmitting optical-to-electrical converter connected to the other end of the optical fiber;
In a free-space optical data link system, the optical signal received by another optical head is converted into an electrical field by a receiving optical-to-electrical converter at the other end of the optical fiber connected to that optical head. A method for regulating an electrical transducer, the method comprising: taking an output from a receiving transducer that is proportional to the amplitude of a received signal; feeding this output to a variable frequency oscillator to obtain a corresponding audio frequency variable tone; A method of conditioning characterized in that the tone is transmitted by an audio frequency link to a transmitting transducer and the transmitting converter is adjusted to a maximum tone pitch corresponding to a maximum signal amplitude. 21. The method of claim 20, wherein the transmitter is a frequency modulation transmitter, the receiving optical-to-electrical converter is a pulse frequency modulation receiver, and the output is taken from a photodiode of the receiver.