BAS E D O N O PTO E L ECT RO N I C CO NVE RT E R S

Field of the Invention

This invention relates to a structure of multisensor generators of video images based on optoelectronic converters such as TV cameras. These generators are meant for instrumentation of on-the-fly positionable systems of remote (and, as necessary, secretive) video observation from one location such extensive objects, length of which exceeds substantially (no less than 10, but often than 100 and more times) their width, e.g. -

Stationary and, especially, displaceable transfer conveyors operate on open pits of minerals or on building sites for the purpose of evaluation of a conveying belt charging evenness and/or transportable dry substances losses;

Forest shelter belts or forest edges during arid periods for the purpose of detection of hotbeds of fire and estimation of flame spreading speed;

Dam sections and river or lake coastlines during floods for the purpose of evaluation of their resistance to water head and detection of sites of breach or dangerous washing out;

Complicated sections of motor roads, railways and canalized waterways during transit of especial importance or bulky goods for the purpose of evaluation of smoothness of such goods motion and detection of on-path irregularities;

Airstrips of any airport before and during takeoff or landing of aircrafts for the purpose of detection of obstacles;

Water areas adjoining to river and sea beaches for the purpose of detection of drowning peoples or dangerous boats motion;

Production lines (especially large automatic assembly conveyors) for the purpose of their failures detection.

Background Art

It is evident that direct observation of above-mentioned and similar extensive objects by a human-operator using any single portable high-resolution TV camera is practically excluded, even if such camera has wide-angle objective.

In fact, if somebody must temporarily oversee at 1000 m distance a motor road section having 2000 m length, he must take into consideration that ratio of visual field sides of such single TV camera is less than ratio of observed object sides in hundreds of times. Accordingly, resolving power of said TV camera becomes the worse, the more intervals between the central part and left or right end of said motor road section. Moreover, this TV camera finds difficulty in focusing, and its interference immunity decreases.

Therefore, conventional systems for video observation of extensive objects have a great number of sequentially arranged on terrain stationary single TV cameras, which are connected to a common data processing center.

Each single TV camera of such systems ensures observation of a released narrow part of an observable extensive object and, correspondingly, maintains sufficient resolving power, acceptable image sharpness and admissible interference immunity.

Unfortunately, such systems for video observation have involved structure and are very expensive. Therefore, assemblage of theirs can go on from a few days to several weeks. Further, such systems do not allow efficient detection of dangers or obstacles, because they do not ensure simultaneous observation of extensive objects in whole. Moreover, they are insufficiently reliable through complication of their complete earthing and sensitivity to atmospheric electricity (see CncTeMbi BHfleoHa6jno,qeHmi ρ,ηη npoMbiwneHHbix npoTfl eHHbix ο6¾βκτοΒ. - ΟΠ6: «TaxnoH», 2014; In English: "Closed circuit television for video observation of industrial and extensive objects". - St. Petersburg: Publishing House «Tachyon», 2014).

Thus, developers of stationary systems for video observation pay principal attention to means of data transmission from each single TV camera into the data processing centers, determination of order of solitary frames view and computerization of auxiliary operations for recognition of such separate video images, where dangers or obstacles are visible.

US 4,51 1 ,886A disclosed a typical example of such stationary system. It based on structural arrangement, which has TV cameras fixed along or on perimeter of observation area with appointed interspaces between them and is additionally equipped by movement detectors, microphones having preliminary sound amplifiers, or other alert sensors. All TV cameras are connected to a data processing center through a commutator, which can operate at the operator's option or at a signal of any alert sensor, a transmitter equipped with a reducer of analogous video images and an accumulation buffer, and a coaxial cable.

A more perfect system according to the US 6,084,631 ensures real-time control of remote TV cameras by bidirectional successive digital communication that can be realized using two twisted pair of wires, fiber-optic cables and even a radio channel.

At present multiple examples of stationary systems for video observation based on numbers of sequentially arranged on terrain immovable TV cameras are known (see RU 2250503; US 2008/0198268; RU 2517042 and many others). Unfortunately, such systems are unsuitable for rapid positioning/removal and for simultaneous video observation from one location of above mentioned and similar extensive objects as a whole.

It is strange that anybody no draws until now attention to creation of equipments for video observation of extensive objects on the basis of high-resolution television systems [see many patents for invention based on PCT/UA96/00016 (WO 98/1 1722)]. This system is equipped with multisensor generator of video images based on optoelectronic converters such as TV cameras, which are fixed within common box-type housing in such manner that viewing fields of theirs overlap partly each other. This housing is suitable for carrying or conveyance. Each such system realizes process that includes following basic steps -

Simultaneous generation of a set of initial fragmentary analogous video signals, which contain information about all released parts of an observable object at definite points of time, Simultaneous conversion of each set of these fragmentary analogous video signals into respective set of fragmentary digital video signals;

Processing of each regular set of these digital video signals for the purpose of correction of geometric distortions and their stitching into an integral digital video signal contained on-line information about entire observable object at each definite points of time.

After priority date of PCT/UA96/00016 many multisensor generators of integral video images based on immovable TV cameras had been created. They have operating frequency no less than 25 fps. This allows -

To observe on-the-fly current state of entire relatively small-sized observable objects using suitable monitors, and

To record observation results for the purpose of long-term storage of theirs and (often repeated) posterior analysis.

Unfortunately, practically all well-known multisensor generators of such fragmentary analogous video images, which is suitable for following creation of integral digital video signals, are meant for use only in X-ray diagnostic equipments and unsuitable for video observation of extensive objects.

Though, disclosed in the WO 2006/049589 and RU 2284089 multisensor generator of fragmentary analogous video images based on optoelectronic converters can be considered as prototype of a proposed below device. This generator has a lightproof box-type housing, a front wall of which is capable for passing-through of electromagnetic (especially, X-ray) radiation, and a positioned behind said wall a block of such formers of fragmentary analogous video signals, which create in operative position information about all released parts of an observable object. Each such former has serially arranged along ray path a multiple-lens objective and an optoelectronic converter (especially TV camera). Viewing fields of adjacent multiple-lens objectives overlap partly each other. All electric outlets of said formers of fragmentary analogous video signals can be connected to a common external data processing center that can create, in operative position, integral digital video signals contained information about an observable object as a whole.

The known block of formers of fragmentary analogous video signals is shaped as rigid rectangular matrix, in which optical axes of all objectives and optoelectronic converters are always parallel.

This allows formation of integral video images only of compact objects such as organs of human or animal organisms (in filmless roentgenography), or machine components (in industrial X-ray examination).

However, rectangular matrix, where optical axes of all objectives and optoelectronic converters are parallel, does not use for the purpose of simultaneous observation of extensive objects, which have length in the range from several tens to several thousands meters and which must be observing from one position at distances that are commensurable with their length. In fact, such matrix must have length that is equal to the length of an observable object. It stands to reason that is impossible. Summary of the Invention

The invention is based on the problem - by change of design and arrangement of components - to create such multisensor generator of video images based on optoelectronic converters that allow simultaneous observing such extensive objects, length of which exceeds substantially their width, from one location at long distances and also simultaneous generation of such uninterrupted sets of fragmentary analogous video signals, which correspond to all released short parts of said extensive objects and can be converting further into integral video images of observable objects using known algorithms.

This problem has solved in that a multisensor generator of video images based on optoelectronic converters comprising -

(1 ) A lightproof box-type housing, a front wall of which is capable for passing-through of electromagnetic radiation, and

(2) A block of formers of fragmentary analogous video signals about released parts of an observable object, at that

- said block of formers is positioned behind said front housing wall,

- each such former has a multiple-lens objective and an optoelectronic converter located serially along ray path,

- viewing fields of adjoining multiple-lens objectives overlap partly each other, and

- electric outlets of all said optoelectronic converters are capable for connection with an external system for generation of integral digital video signals contained on-line information about an entire observable object at definite points of time,

according to the invention characterized in that the front housing wall has a lengthwise slot for passing-through of visible light, and these formers of fragmentary analogous video signals have used in number no less than three and are located oppositely to the said slot on one level in one row fan-like.

Even this simplest embodiment of the invention ensures possibility to create such systems for simultaneous video observation of entire extensive objects at distances commensurable with their length that can be rapidly placed at any selected point or also rapidly removed from this point. Those functional capabilities of these systems are the greater, the more said formers of fragmentary analogous video signals will be fan-like arranged in one row.

An additional feature consists in that said slot is variable diaphragm. This allows optimizing light flux incident onto the optoelectronic converters depend on visual field illuminance and, as necessary, to ensure protection from natural or technical disturbances such as sun glints, lightning flashes, blinding glares of headlights etc.

Further, said formers of fragmentary analogous video signals are equipped with long- focus varifocal objectives. This allows equalizing measure and sharpness of video frames of any observable extensive object along all length of it.

Moreover, said formers of fragmentary analogous video signals are mounted with possibility of controllable turn and reciprocal linear motion and fixation in selected position. This allows to adjust angle of fan opening depend on extent of an observable object and to locate of said multiple-lens objectives at the same distance to the said lengthwise slot.

Next additional feature consists in that said formers of fragmentary analogous video signals have used in odd number no less than five. This simplifies regulation of fan pattern.

And, finally, said angle of fan opening is selected in the range from 30° to 120°. This allows creating systems for video observation objects having various lengths.

Brief Description of the Drawings

The invention will now be explained by detailed description of a multisensor generator of video images based on optoelectronic converters with references to the accompanying drawings, in which:

Fig.1 shows a general view of simplest multisensor generator of video images (axonometric view, where a cover, two side walls and rear wall of a box-type housing are removed for convenience);

Fig.2 shows a scheme of arrangement of formers of fragmentary analogous video signals in the event of video observation of a relatively short extensive object (plan view);

Fig.3 shows a scheme of arrangement of fragmentary analogous video signals in the event of video observation of a long extensive object (plan view).

Best Embodiments of the Invention

Any proposed multisensor generator of video images comprises (seeFig.1 ) -

A lightproof box-type housing 1 , a front wall 2 of which has a no designated especially lengthwise slot for passing-through of visible light, at that this slot is usually equipped with at least one movable shutter 3 and, accordingly, serves as variable diaphragm;

A block of formers 4 of fragmentary analogous video signals containing information about released parts of any observable extensive object.

Each former 4 has a multiple-lens (preferably long-focus varifocal) objective 5 at its optical input and located further along ray path an optoelectronic converter 6 (as a rule, in the form of a TV camera). These formers 4 - have used in number no less than three (and preferably in odd number, e.g. five or more),

are arranged on the housing 1 bottom behind said front wall 2 on one level in one row fan-like in such manner that their viewing fields overlap partly each other,

have no shown especially electrical outlets for connection to an external system that can form integral digital video signals contained on-line information about an entire observable extensive object at definite points of time, and

are usually mounted with possibility of controllable turn and reciprocal linear motion and fixation in selected position (for convenience, directions of said turn and said linear motion are showed correspondingly by pairs of anti-circular and anti-parallel arrows only for one former 4). It is advisable (but not obligatory), if angle of fan opening is chosen in the range from 30° to 120°.

As it had mentioned above, the proposed multisensor generator of video images is meant for use in such video observation systems, which allow viewing any extensive objects in whole from one location under condition that distances from said objectives 5 to the released parts of each observable object are commensurable with its length.

Typical structure of a television system for video observation had disclosed in essence in above-mentioned WO 98/11722. It can be used also in systems for video observation of extensive objects, when they will be equipped with the proposed multisensor generator of video images based on the described above block of formers 4. Correspondingly, this structure must include well-known at present and severally available at world market - an analog-digital converters unit (ADCs),

a video signals standards converter,

a random-access memory (RAM),

facilities for synthesis of integral output digital video signals on the basis of a multichannel corrector of geometric distortions and a synchronizer,

a central processing unit based on personal computer (PC),

at least one video monitor (but preferably several video monitors that are arranged in a row without clearances), and, optionally,

facilities for recording video observation data onto long-term storages. At that - the multi-channel corrector must be connected through the ADCs unit to electric outlets of said optoelectronic converters (i.e. usually TV cameras) 6 and through the video signals standards converter and the RAM to the PC data input, and

the synchronizer must be connected through own driving point to a synchronizing output of at least one TV camera 6 and through own controlling outputs to a clock input of the ADCs unit to the address inputs of the multi-channel corrector of geometric distortions and to the address and controlling synchronizing inputs of the video signals standards converter.

It is understandable for each person skilled in the art that any system for video observation of extensive objects based on the proposed multisensor generator of video images can be equipped additionally with well-known and generally available auxiliary facilities for automation of setting on a selected observable object and for adaptation to current conditions of observation of it, such as:

electric micro motors and transmission gears for programmed turns and reciprocal movements of said formers 4 and their fixation in selected positions by suitable usual stop members;

as a rule, programmed setters and sensors of required and actual angular positions and linear displacements of said formers 4 within the housing 1 ;

luminance sensors at optical inputs of said formers 4; at least one (preferably laser) meter of distance from each individual former 4 to a released to it part of an observable extensive object (Remark. These distances are the greater, the longer is the selected object, the farther any its part is away from center of such object, and the farther it is away from the proposed generator of video images);

an unit for control of position of shutter 3 of said variable diaphragm and an actuator for automatic displacement and retention of it in required position;

actuators for focusing and adjustment of focal distances of said long-focus varifocal objectives 5.

Naturally, all electric micro motors of such video observation system must be connected in a well-known way to suitable current sources through programmable switches.

It is understandable also for each person skilled in the art that two variants of systems for video observation of extensive objects can be made, namely:

stationary systems, which can be positioned on a chosen place and in good time adjusted for long-term observation of a selected object, e.g., a specific section of a motor road, or a railway, or a canalized waterways, or an airstrip etc., and

movable systems, which are suitable for rapid relocation, as the need arises.

Multisensor generators of video images for stationary video observation systems can be usually custom-made. Respectively, number of the formers 4 of fragmentary analogous video signals and angle of fan opening can be stated in good time on the assumption of chosen extensive object length and average distance to it. For instance:

from three to five formers 4 having unregulated multiple-lens objectives 5 and angle of fan opening no more than 60° will be enough for video observation of relatively short (about 100 m length) conveyor belts at analogous distance,

whereas video observation of any airstrip or many forest edges requires usually no less than twelve formers 4 having long-focus manually adjusted varifocal objectives 5 and angle of fan opening up to 120°.

The proposed multisensor generator of video images meant for movable systems of video observation can produce serially using preferably more than five formers 4 having long-focus varifocal objectives 5 and, optionally, facilities for automatic control of angle of fan opening, image focusing and focal distance of each objective 5.

Examples of fan opening are showed on figs 2 and 3.

Any multisensor generator of video images based on optoelectronic converters 6 operates as follows.

It must be together with an appropriate external system for video observation brought onto a selected position relative to a specified extensive object. Then each objective 5 of each former 4 must be directed at respective released part of the observable extensive object. Because the viewing fields of the adjoining objectives 5 are overlapped (usually no more than 10%), all converters 6 generate at their electrical outlets such set of fragmentary analogous video signals that correspond with all observable object and will be enough and to spare.

Regulation of light quantity incident on the objectives 5 (and, correspondingly, on optical inputs of the optoelectronic converters 6) and their (usually automatic) protection from flare light can be ensured by displacement of the movable shutter 3 of variable diaphragm, which is provided, as a rule, in structures of such multisensor generators of video images that are meant for use on open territory.

Regular sets of fragmentary analogous video signals can be generated with predetermined clock frequency (usually 25 fps, as it is approved in television systems). Each such set enters into data input of aforesaid external system for video observation of the specified extensive object. This system synthesizes integral output digital video signals on the basis of said sets of fragmentary analogous video signals, displays video images on the basis of said integral output digital video signals to a human-operator and records observation results for posterior check views.

When observation of the specified extensive object would have completed, the shutter 3 of variable diaphragm must be closed, and the system for video observation can be rapidly disassembled or converted into stowed position.

Industrial Applicability

Multisensor generators of video images can be serially made using available components (specifically, long-focus varifocal objectives and preferably TV cameras as optoelectronic converters) and known machinery and tools. Analogously, alignment of optical systems and adjustment of kinematic chains can be realized by use of known calibrators. Ready-made generators can be used for kitting-up of preferably movable systems of remote video observation of extensive objects from one predetermined location.