Abstract:
A quick-acquisition optical sight for short-distance aiming or viewing enhanced with an illuminated reticle, e.g., a red dot, and intended for installation on a conventional long-distance viewing apparatus, the combination thereof comprising an integral assembly consisting of a mounting part attachable directly to the tubular scope without any intermediate adapters and a housing with an optical system that is pivotally supported by the mounting part. In spite of the fact that the quick-acquisition sight is approximately 30% smaller and less heavy than the smallest existing sight of this type, it incorporates click-type mechanisms for adjusting the position of the sight optical axis relative to the optical axis of the scope.

Description:
FIELD OF THE INVENTION 
       [0001]    The present invention relates to optical sights for weapons, measurement instruments, geological surveying instruments, or the like, and more specifically to optical sights with a wide range of observation distances. In particular, the invention relates to a miniature red-dot-enhanced quick-acquisition optical sight for installation on a tubular optical scope, wherein the tubular optical scope is used for long-distance viewing or shooting and the quick-acquisition sight is used for short-distance viewing or shooting. 
       BACKGROUND OF THE INVENTION 
       [0002]    Various sighting devices are known for aiming firearms and the like. Firearms typically employ two sights that are spaced from one another along a line substantially parallel to the path along which a projectile will be discharged. A user holds the firearm manually so as to view over and/or through the two spaced sights toward the target and discharges the firearm. Adjustments can be made mechanically on the sight or manually by the user to adjust for windage and elevation. In any event, the objective is to align the firearm accurately with the target by viewing along a line to the target, as defined by the spaced sights, and holding the firearm along that line. 
         [0003]    Various modern sights include open sight, peep sight, and scope. Open sights are typically used on handguns and rifles. An open sight includes a front sight in the form of a blade member which is located at the extreme front end of the firearm. The rear sight is in the form of a planar member having a horizontal notch therein. The rear sight is typically positioned along the barrel or over the chamber portion of the firearm. To aim the firearm, a shooter aligns the front sight with the notch in the rear sight. The firearm is aligned vertically by setting the top edge of the front sight even with the top of the notch in the rear sight. The firearm is aligned laterally by centering the front sight within the notch. The intended target should now appear just against the top of the front blade. The front and rear sights are sized in order to place the discharged projectile on the target viewed within a certain range, provided the sights are properly aligned. 
         [0004]    In practice, the rear sight is closer to the shooter than the front sight, and the target is a substantially greater distance away. Thus, it is necessary for the shooter to determine where to focus his or her eyes. If the shooter focuses on the target, the sights will appear blurred. If the shooter focuses on the sights, the target will appear blurred. A similar situation is encountered when the shooter attempts to focus on front or rear sights. This situation is not as pronounced, however, because the distance between the front and rear sights is small. 
         [0005]    While shooters can shift their focus between the sights and the target, they are taught to focus on the sights rather than the target when discharging the firearm. This allows the shooter to concentrate and clearly center the front and rear sights. While it is not necessary for the target to be in focus when the firearm is aimed, the reverse is not true. Misalignment of the sights will result in a missed shot even if the target can be clearly seen. 
         [0006]    As a result of the above limitations, open sights are generally accurate only for targets within a local focal range of 25 meters for most handguns, although some rifles include open sights that are graduated to greater distances. As the distance to the target increases, the view of the target degrades and accuracy declines rapidly. Telescopic sights are helpful for longer distances because the cross hairs can be arranged so that they appear focused when viewing the target through the sight. 
         [0007]    Among a great variety of various telescopic optical sights known in the art, one such sight attachable to a firearm is described, e.g., in U.S. Pat. No. 5,924,234 issued to G. Bindon, et al., in 1999. This is a typical telescopic sight having an objective lens assembly, an eyepiece lens assembly, and an illuminated reticle imposed onto the vision view of the optical sight. If this sight has been focused to aim at a remote target but the shooter has to hit a close target, which appeared in his/her field of vision for a very short period of time, the close target can disappear sooner than the shooter could refocus the optical sight. Furthermore, the range of shooting distances inherent in optical telescopic sights lie within the limits of approximately 30 m to several hundred meters or several kilometers. In general, an optical telescopic sight is not suitable for hitting targets at distances closer than 30 m. Moreover, the use of telescopic sights at short shooting distances is extremely inconvenient because the telescopic optics has a limited aperture so that only a narrow scene can be observed in the optical sights focused to short distances. 
         [0008]    Quite often however, such circumstances are usually accompanied by other difficulties as well. For example, one such circumstance may occur on a battlefield. Under battlefield conditions it is highly advantageous to have an optical sight that has both a wide field of view and a narrow field of view available to the user. For example, it is quite advantageous for a gunner to be able to select a target over a wide range of distances. Hence, an optical sight with one set of optical elements having a wide field of view for relatively closer-range targets and a second set of optical elements which, when positioned in the optical path of the first set of optical elements, presents a narrow field of view for relatively distant targets and provides a gunner with the ability to select, track and/or attack targets over a large tactical battlefield. 
         [0009]    An attempt to solve the above problem is described in U.S. Pat. No. 5,548,442 issued to G. Devenyi in 1996 and in U.S. Pat. No. 5,691,842 issued to the same inventor in 1997. These patents describe an optical assembly that includes a first plurality of optical elements providing the viewer with a first field of view and a second plurality of optical elements that, when moved into the optical path of the sight, provides the viewer with a second field of view. This is achieved by providing the sight with an optical lens subassembly installed so as to rotate inside the sight housing with the axis of rotation transverse to the optical axis of the sight. In one position of the optical lens subassembly, the optical axis of this subassembly coincides with the optical axis of the sight, and the lenses of the subassembly are included in the optical scheme. This position corresponds to one field of view. When the optical lens subassembly is turned 90° from the first position to the second position, the lenses of the subassembly are removed from the optical scheme, and the light beams freely pass through the windows provided in the subassembly configuration. U.S. Pat. No. 6,226,880 issued in 2001 to R. Pitre describes a quick-focusing firearm scope, which includes an elongated tubular scope housing mounted to the upper surface of the firearm barrel. A focusing gear is provided in place of the conventional rotating focusing ring found on conventional scopes. Mounted adjacent to and engaging the focusing gear is a drive gear having a cable attached thereto. The opposing end of the cable extends through a support member that is mounted to the firearm trigger guard. Pivotally attached to the support member is a trigger member having an arcuate gear attached to the upper end thereof that engages the rotary gear on the cable. The lower end of the trigger member includes a loop that receives the shooter&#39;s trigger finger. Accordingly, the shooter may quickly focus the scope by pivoting the trigger member with the index finger. This allows the shooter to quickly focus the scope without removing his or her hand from the trigger. 
         [0010]    Nevertheless, the device of U.S. Pat. No. 6,226,880 does not solve the problem of switching from a distant telescopic sight to a close sight, a feature inherent in conventional non-optical rifle sights. 
         [0011]    Optical sights intended only for short-distance shooting are known. One such device is described, e.g., in U.S. Pat. No. 6,516,551 issued in 2003 to L. Gaber. This patent describes an optical sight for a photocamera or for an aiming device of a firearm, which comprises a combination of a light-emitting-diode (LED) with a plurality of reticle patterns applied onto the surface of the LED and selectively illuminated by connecting various portions of the reticle pattern to an electric power supply source. Switching from one pattern to another is carried out electrically and therefore without the need to move the reticles or reticle images. This ensures high accuracy in positioning of reticle elements with regard to each other, e.g., with regard to the front sight center of the partially transparent mirror and, hence, with regard to the ballistic trajectory of the bullet. 
         [0012]    More specifically, the aforementioned LED is installed on a mounting plate in the proximal part of the sight and is positioned offset from the optical axis of the sight. The distal part of the mounting plate supports a concave, partially transparent mirror through which the viewer can see a target. A special mirror coating passes approximately 95% of the light and reflects approximately 5% of the light incident on the mirror. The LED is spaced from the coating of the mirror at a distance equal to half the radius of the curvature on the concave surface of the mirror. The aforementioned reflected part of the light has the shape of a collimated beam. The sight is further provided with an eyepiece, and the mirror coating is arranged so that the beam reflected from the mirror surface is aligned with the axis of the eyepiece. If the beam carries an image (reticle), this image will be localized on the retina of the viewer&#39;s eye and will be seen as if it is located in infinity. The reticle image will be imposed onto the image of a target seen through the partially transparent mirror. 
         [0013]    The sight of the aforementioned type is intended for aiming at objects located at short distances, that is, which normally do not exceed 100 meters. The only purpose of this sight is to facilitate aiming by using a virtual illuminated aim (reticle). It is understood that this sight is suitable for aiming only at objects that are visible with a naked eye and therefore is unsuitable for aiming at remote and poorly visible targets, e.g., during dusk or nighttime. Another drawback of sights having an illuminated or virtual sight is the inaccuracy of aiming caused by parallax. Parallax is the apparent displacement of an observed object (target), which occurs when the viewer changes his/her position with respect to this object. Parallax is inevitable because during each aim, the viewer&#39;s eye assumes a different position with respect to the sight. The closer the virtual sight (reticle) to the viewer&#39;s eye, the greater is the parallax. For this reason, rifles allow better aiming and shooting accuracy than guns, which have shorter barrels than those of rifles. However, tubular optical sights for rifles are not applicable to aiming and/or shooting at close targets that may suddenly appear in front of the user and that require an angle of observation much wider than one provided by the telescopic sight. 
         [0014]    An attempt to solve this problem was made by the inventor herein in his earlier U.S. Pat. No. 6,487,809 issued in 2002. This patent discloses an optical sight system with a wide range of shooting distances that comprises a combination of a telescopic optical sight with a reticle-type sight. Both optical sights are located inside a closed casing. The reticle sight consists of a partially transparent mirror attached to the outer surface of the telescopic sight at the distal end of the telescopic sight. The telescopic sight supports on its outer surface a light source, which emits a light beam onto the aforementioned partially transparent mirror. The mirror reflects a part of the beam incident on its surface toward a full-reflection mirror attached to the outer surface on the proximal end of the telescopic tube. This mirror is interlocked with the second full-reflection mirror so that when the first full-reflection mirror receives the beam reflected from the semitransparent mirror and carries the image of the reticle, the second full-reflection mirror closes the eyepiece lens assembly of the telescopic sight and, at the same time, reflects the image of the target and of the reticle imposed thereupon to the viewer&#39;s eye. When it is necessary to use the telescopic sight to aim at a distant target, the first full-reflection mirror is turned away from the path of the aforementioned beam that carried images of the target and of the reticle, whereas the second full-reflection mirror uncovers the eyepiece lens assembly of the telescopic sight. 
         [0015]    Also known in the art is an optical sight with so-called “Doctor Optics” commercially produced under the trademark “TA01NSN-DOC: 4×32 Trijicon ACOG® which is equipped with a quick-acquisition sight known as “7.0 MOA Docter®” and which mounts in tandem with the Trijicon ACOG® Scope. The compact tubeless design allows for low weight without sacrificing performance. The TA01NSN-DOC combines the technology of the battle-tested Trijicon ACOG (4×32) gun sight with the Doctor Optic 7.0 MOA Red Dot Sight. This provides the shooter with the option of quick-acquisition close-range sighting with the Doctor Sight and the precision for longer-range shooting with the Trijicon ACOG 4×32. This ability to adjust to tactical situations gives the user the needed edge when lives are on the line and success is the only acceptable outcome. The ranging [?] reticle allows for bullet-drop compensation to 600 meters without manual adjustment. The reticle appears black during daytime and glows amber in the dark, thanks to Trijicon&#39;s patented tritium illumination. The DOCTER Sight offers a large field of view due to its low magnification and is firmly factory-adjusted and parallax-free to 40 yards. This adjustment ensures that parallax-related aiming errors are minimized over a long-distance range. 
         [0016]    The optics consists of two firmly connected glass lenses. The functionally important coating reflecting the aiming dot is applied to one of the inside surfaces, which provides maximum protection against scratches. Additionally, the outer surfaces of the lenses are antireflection coated with resistant layers. All components and mounting elements exposed to mechanical stress are made of high-grade materials, such as stainless steel and hard-anodized aluminum alloys. 
         [0017]    Adapters of many other types are available. For example, U.S. Pat. No. 7,272,904 issued in 2007 to M. Lame discloses a throw-lever releasable mounting system for mounting a device in quick-release manner to a support member. The device has a mounting base having a configuration fitting opposed angulated rail surfaces and having a locator key engaging a positioning slot of the rail. Each mounting base provides for mounting and stabilization of optics mounting rings. A locking platform projects from the mounting base and defines a locking opening having a circular hard metal insert therein that defines a receptacle receiving a resilient member and providing for location of the spline/spindle shaft of a rotatable locking plate. A locking plate of a throw-lever that can be rotated between locking and unlocking positions has angulated and curved cam surfaces for forcibly engaging correspondingly angulated surfaces of the rail to achieve cam-energized precision locating and locking engagement with the rail. A non-circular section of a spline/spindle shaft of the throw-lever receives a drive member in non-rotatable and linearly moveable relation. Resilient members are interposed between the drive member and the hardened insert and prevent free throw-lever movement at the release position thereof. 
         [0018]    The smallest and lightest quick-acquisition sight of the aforementioned conventional type available on the market today is the AIMPOINT® MICRO H-1 sight manufactured by Aimpoint AB, Sweden. Nevertheless, the weight of this sight with the mount adapter is 105 g, and the length is 62 mm, which is not yet completely satisfactory. 
         [0019]    A disadvantage of all aforementioned quick-acquisition sights is the significant limitation in the vertical dimension since sights must fit into a predetermined space limited in the vertical direction by restricted distance between the optical axes of the main tubular sight and the quick-acquisition sight. Therefore, the conventional device, which is attached to the scope through a separate adapter means, must be very small to the extent that the construction thereof does not provide enough room for incorporation of a conventional click-type adjustment mechanism to which a user is accustomed. Instead of this, conventional non-click screws are used because of the aforementioned limitations. Another limitation is the longitudinal dimension associated with eye-relief requirements. These restrictions create difficulties in designing sight-adjustment mechanisms needed for adjusting the position of the optical axis of the quick-acquisition sight in vertical (elevation) and horizontal (windage) directions in a reliable and simple manner with quantitatively evaluated displacements that can be provided by the click system. 
       OBJECTS AND SUMMARY OF THE INVENTION 
       [0020]    It is an object of the present invention to provide a quick-acquisition sight that is simple in construction, convenient in installation on a tubular scope, and miniature in dimensions and that incorporates a click-type adjustment mechanism. It is another object to provide a quick-acquisition sight of the aforementioned type, the design of which fits into a space limited by the design of the scope and is to a lesser degree limited in the vertical direction. It is a further object to provide a quick-acquisition sight that does not require the use of separate adapters. It is a further object to provide a quick-acquisition sight of the aforementioned type, the housing of which incorporates mounting features for the adapter and thus diminishes restrictions with regard to the vertical dimension of the sight. It is a further object of the invention to provide a quick-acquisition sight of the aforementioned type that is superior to conventional sights of this type with regard to design capabilities. It is a further object to provide a quick-acquisition sight that has a quickly removable cover to allow use of the sight in an open or closed fashion. It is a further object to provide a quick-acquisition sight that incorporates a conventional click system for adjusting positions of the sight optical axis. 
         [0021]    In general, the red-dot-enhanced quick-acquisition optical sight (hereinafter referred to as “QAO sight”) of the invention comprises a single indivisible assembly that is intended for aiming at close targets not coverable by the main remote-target scope, that can be attached directly to the main scope, i.e., without any additional adapters, and that incorporates conventional click-type adjustment mechanisms for displacing the optical axis of the quick-acquisition optical sight in vertical (elevation) and transverse (windage) directions relative to the optical axis of the main scope. The QAO sight assembly consists of a mounting part, which is made in the form of a bracket with an attachment flange for securing the QAO sight directly to the mating part of the main tubular scope without the use of any intermediate adapters, and a housing with an optical system, the front end of which is pivotally connected to the front end of the mounting part with possibility of pivotal movements in the vertical plane. Since the upper part of the housing supports an optical lens of the QAO sight, these vertical displacements are used for elevation adjustment in the position of the optical axis of the QAO sight. Adjustment in the elevation direction is carried out by means of a screw accessible to the user from the upper side of the housing when the protective cover is removed. The adjustment mechanism consists of the aforementioned screw that supports a sleeve with a plurality of circumferentially arranged dimples that interact with a spring-loaded projection or a spring-loaded ball that in the course of rotation of the screw falls into the aforementioned dimples, producing sensible clicks. By counting the number of clicks, the user can quantitatively evaluate the amount of vertical or elevation adjustment in the position of the QAO sight. The pivot end of the mounting part incorporates a nut that is engaged with a transverse-adjustment screw. Access to this screw is available from the side wall of the housing. Similar to the mechanism of the elevation adjustment, the transverse-adjustment screw supports a sleeve with a plurality of circumferentially arranged dimples that interact with a spring-loaded projection or a spring loaded ball fixed in the housing that in the course of rotation of the screw falls into the aforementioned dimples, producing sensible clicks. By counting the number of clicks, the user can quantitatively evaluate the amount of transverse or windage adjustment in the position of the QAO sight. Such adjustment mechanisms are known, per se, and are used in conventional optical sights. However, because of the aforementioned limitations, the known QAO sights have no room for incorporation of the conventional click-type adjustment mechanisms. In the QAO sight of the invention, this became possible by combining the optical part with the mounting part, which is tailored for a specific scope into a single indivisible unit, the design of which expands possibilities for incorporation of click-type adjustment mechanisms. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0022]      FIG. 1  is a general three-dimensional view of the quick-acquisition optical sight of the present invention in combination with the main tubular optical sight. 
           [0023]      FIG. 2  is a longitudinal sectional view of the quick-acquisition optical sight of  FIG. 1  along line II-II of  FIG. 1 . 
           [0024]      FIG. 3  is a front view of the quick-acquisition optical sight of  FIG. 1  in the direction of arrow A of  FIG. 1 . 
           [0025]      FIG. 4  is a bottom view of the quick-acquisition optical sight of  FIG. 1 . 
           [0026]      FIG. 5  is a sectional view along line V-V of  FIG. 4 . 
           [0027]      FIG. 6  is a sectional view along line VI-VI of  FIG. 5 . 
           [0028]      FIG. 7  is a rear view of the tubular optical scope, the cylindrical housing of which is embraced and clamped by bolts between the semicircular yoke and the correspondingly shaped mounting part of the sight of the invention. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0029]    In general, the QAO sight of the invention comprises a quick-acquisition optical sight with a red-dot indication function that comprises a single indivisible assembly that is intended for aiming at close targets not coverable by the main remote-target scope and that can be attached directly to the main scope, i.e., without any additional adapters. The QAO sight of the invention incorporates conventional click-type adjustment mechanisms for displacing the optical axis of the quick-acquisition optical sight in the elevation and windage directions relative to the optical axis of the main scope. In firearms terminology, windage refers to the side-to-side adjustment of a rifle&#39;s sight, which is used to change the horizontal component of the aiming point. 
         [0030]    A general three-dimensional view of a QAO sight  20  of the present invention is shown in  FIG. 1 , wherein the QAO sight  20  is attached directly, i.e., without use of conventionally employed adapters or special mounting plates, to the housing  22  of an elongated tubular scope  24 , which can be, e.g., a Trijicon ACOG® Scope produced by Trijicon Inc., MI, USA. The tubular scope  24 , in turn, is mounted to the upper surface of a firearm barrel (not shown). The shape and dimensions of the mounting flanges (only one of which, i.e., the mounting flange  26 , is shown in  FIG. 1 ) of the QAO sight  20  are made so as to directly attach the QAO sight  20  to the housing  22  of the scope  24 , e.g., by bolts, one of which, i.e., a bolt  28 , is shown in  FIG. 1 . The QAO sight  20  is a sight of an open type that has an optical lens  32  on the distal end of a sight assembly housing  30  and an auxiliary view-limiting frame  34 , the presence of which in the QAO sight  20  is provisional. Reference numeral  36  designates a protective cover that can be used for closing the sight during inoperative times, e.g., during transportation or storage, for the purpose of protecting the interior parts of the sight from contamination with dirt, dust, etc. 
         [0031]      FIG. 2  is a longitudinal sectional view of the QAO sight  20  along the line II-II of  FIG. 1 .  FIG. 3  is a front view of the QAO sight  20  in the direction of arrow A of  FIG. 1 , and  FIG. 4  is a bottom view of the QAO sight  20 . 
         [0032]    It can be seen that the QAO sight assembly  20  consists of a mounting part  38  ( FIGS. 2 ,  3 , and  4 ), which is made in the form of a bracket with attachment flanges  40   a  and  40   b  for rigidly securing the QAO sight  20  directly to the mating part of the main scope  24  without use of intermediate adapters, and a moveable sight housing  42  ( FIG. 2 ) with an optical system, the front end of which is pivotally connected to the front end of the mounting part  38  on a pin  44  ( FIG. 2 ) with possibility of pivotal movements in the vertical plane, i.e., in a plane perpendicular to the mounting part  38 . 
         [0033]    Since the upper part of the housing  30  supports an optical lens  32  of the QAO sight  20 , these vertical displacements are used for elevation adjustment of the optical axis X 1 -X 1  of the QAO sight ( FIGS. 1 and 3 ). The adjustment in the elevation direction is carried out by means of a click-type elevation adjustment mechanism  45  that contains a vertical screw  46  ( FIG. 2 ) accessible to the user from the upper side of the housing  30  when the protective cover  36  is removed. The elevation adjustment mechanism  45  consists of the aforementioned screw  46  that supports a sleeve or a shoulder  48  with a plurality of circumferentially arranged dimples  50  that interact with a spring-loaded projection or a spring loaded ball  52  that in the course of rotation of the screw  46  falls into the aforementioned dimples, producing sensible clicks. By counting the number of clicks, the user can quantitatively evaluate the amount of the elevation adjustment in the position of the QAO sight axis X 1 -X 1 . The screw  46  rotates and engages a nut  47  that has some freedom of movement in a yoke (not shown) and that is pressed to a thrust member  49  of the mounting part  38  ( FIG. 2 ) and displaces the housing  30  during rotation of the screw  46  in the vertical direction relative to the mounting part  38  ( FIG. 2 ). Displacement is carried out against the force of a pair of springs (not shown), which are compressed between the housing  30  and the mounting part  38 . 
         [0034]    Shown in  FIGS. 5 and 6A  is a click-type windage-adjustment mechanism  39  for adjusting the position of the housing  30  (and hence the optical axis XI-XI of the QAO sight  20 ) together with the red-spot-projecting diode  54  ( FIG. 2 ) in the transverse direction relative to optical axis X-X.  FIG. 5  is a sectional view along line V-V of  FIG. 4 , and  FIG. 6  is a sectional view along line VI-VI of  FIG. 5 . In principle, this mechanism is similar to the mechanism of elevation adjustment described earlier. As shown in  FIG. 5 , the pivot end of the mounting part  38  incorporates a nut  56  that is engaged with a transverse-adjustment screw  58 . Access to this screw  58  is available from the side wall of the housing ( FIG. 1 ). Similar to the mechanism of the elevation adjustment, the windage-adjustment screw  58  has a circular shoulder  60  with a plurality of circumferentially arranged teeth  62  and dimples  64  ( FIG. 6 ) formed between them which interact with a spring-loaded projection or a spring-loaded ball  66  fixed in the housing  30 . During rotation of the screw  58 , the spring-loaded projection or ball  66  falls into the aforementioned dimples  64 , producing sensible clicks. By counting the number of clicks, the user can quantitatively evaluate the amount of windage adjustment in the position of the QAO sight. Such adjustment mechanisms are known, per se, and are used in conventional optical sights. However, because of the aforementioned limitations, the known QAO sights have no room for incorporation of conventional click-type adjustment mechanisms. In the QAO sight  20  of the invention, this became possible by combining housing  30  that carries the optical part with the mounting part  38 , which is tailored for cooperation with a specific scope into a single indivisible unit  20 . The design of this unit expands the possibilities for incorporating click-type adjustment mechanisms into a miniature QAO sight  20 . 
         [0035]    For attachment to the tubular scope  24 , the housing  22  of the scope, e.g., the scope of model TA01NSN-DOC: 4×32 Trijicon ACOG® produced by American Technology Network Co., Inc., CA, is provided with a special mounting flange  26  shown in  FIG. 1 . However, the QAO sight  20  can also be attached to a scope that has a round cross section by using a conventional semicircular yoke  68  of the type shown in  FIG. 7 . This drawing is a rear view of the tubular optical scope  22 , the cylindrical housing of which is embraced and clamped between a semicircular yoke  68  located from below and the correspondingly shaped mounting part  38  of the sight  20 . The mounting part  38  and the yoke  68  are interconnected by bolts  67   a  and  67   b  ( FIG. 7 ). In a working position on the scope  24 , an actual working model of the QAO sight  20  of the above-described structure has the vertical distance between optical axes X-X and XI-XI ( FIG. 1 ) not exceeding 40 mm, which is not achievable with the design of any existing quick-acquisition optical sight. 
         [0036]    Thus, it has been shown that the invention provides a quick-acquisition sight that is simple in construction and miniature in dimensions. For example, while the smallest QAO sight AIMPOINT® MICRO H-1 manufactured by Aimpoint AB, Sweden, which is available on the market, has a length of 62 mm, the sight  20  of the invention has a length of 48 mm and, in general, it is smaller in size and weight than the AIMPOINT® MICRO H-1 sight by approximately 30%. This is an essential advantage for a hand-held weapon or an optical instrument. Furthermore, the QAO sight  20  of the invention is convenient to install on a tubular scope, incorporates a click-type adjustment mechanism, fits into a space limited by the design of the scope and is to a lesser degree limited in longitudinal and vertical directions. The sight does not require the use of separate adapters since it incorporates the mounting features of the adapter for direct attachment to the scope and thus diminishes restrictions with regard to the vertical dimension of the sight. The quick-acquisition sight of the invention is superior to conventional sights of this type with regard to design capabilities. It has a quickly removable cover that allows use of the sight in an open fashion or storage and transportation in a closed fashion. The sight incorporates a conventional click system for adjusting positions of the sight optical axis. 
         [0037]    Although the invention has been shown and described with reference to specific embodiments, it is understood that these embodiments should not be construed as limiting the areas of application of the invention and that any changes and modifications are possible provided that these changes and modifications do not depart from the scope of the attached patent claims. For example, the QAO sight of the invention can be attached to a tubular scope of any geometry and size, e.g., to a scope equipped with a zoom mechanism, a scope equipped with a day/night vision device, etc. The mounting part of the scope of the invention can be attached to a flange provided directly on the scope or to an auxiliary attachment means that together with the mounting part of the QAO scope form a clamping mechanism for securing the sight to the scope. The QAO sight, itself, may have different shapes and dimensions without the limits of the patent claims, and its elements can be made from different materials. The click-type adjustment mechanism may have a design different from described in the specification provided that it accomplishes its function. The sight of the invention applies not only to firearms but to geodesic surveying instruments, or the like.