U.S. patent application number 13/246630 was filed with the patent office on 2012-05-31 for method of movement compensation for a weapon.
Invention is credited to John William Lowrey, III.
Application Number | 20120132709 13/246630 |
Document ID | / |
Family ID | 46125950 |
Filed Date | 2012-05-31 |
United States Patent
Application |
20120132709 |
Kind Code |
A1 |
Lowrey, III; John William |
May 31, 2012 |
Method of Movement Compensation for a Weapon
Abstract
A method for stabilizing an image and compensating for movement
of a weapon is provided, comprising: providing an image
stabilization device for an optical scope mounted on a weapon,
wherein the image stabilization device includes a sensor to detect
motion of the weapon; providing a trigger release device
operatively connected to a trigger on the weapon; detecting
movement of the weapon by the sensor; generating an output signal
from the sensor, wherein the output signal corresponds to the
position and velocity of the weapon in a plane perpendicular to the
line of sight; processing the output signal to determine an optimal
release period, and then generating a release signal during the
release period; and using the release signal to activate the
trigger release.
Inventors: |
Lowrey, III; John William;
(Mansfield, LA) |
Family ID: |
46125950 |
Appl. No.: |
13/246630 |
Filed: |
September 27, 2011 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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11076340 |
Mar 8, 2005 |
8074394 |
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13246630 |
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Current U.S.
Class: |
235/407 |
Current CPC
Class: |
F41C 27/22 20130101;
G02B 27/646 20130101; F41G 3/08 20130101; F41G 11/00 20130101; G02B
23/14 20130101; F41G 3/06 20130101; F41G 1/38 20130101; F41G 3/12
20130101 |
Class at
Publication: |
235/407 |
International
Class: |
G06G 7/80 20060101
G06G007/80 |
Claims
1. A method for stabilizing an image through an optical scope and
compensating for movement of a weapon directing a projectile along
a line of sight, comprising: providing an image stabilization
device for an optical scope mounted on a weapon, wherein the image
stabilization device includes a sensor to detect motion of the
weapon; providing a trigger release device operatively connected to
a trigger on the weapon; detecting movement of the weapon by the
sensor; generating an output signal from the sensor, wherein the
output signal corresponds to the position and velocity of the
weapon in a plane perpendicular to the line of sight; processing
the output signal to determine an optimal release period, and then
generating a release signal during the release period; and using
the release signal to activate the trigger release.
2. The method of claim 1, wherein the release period is determined
based upon an accuracy selection predetermined by a user.
3. The method of claim 1, further comprising: providing a trigger
pull detection device adapted to determine if the trigger has been
pulled by a user; and using the release signal to activate the
trigger release only if the trigger pull detection device indicates
that the trigger has been pulled.
4. The method of claim 1, further comprising the step of
determining the range of a target, and adjusting the optical scope
for the determined range and ballistics characteristics of the
projectile.
5. The method of claim 4, wherein the optical scope is adjusted
electronically by a rangefinder in communication with the image
stabilization device.
6. The method of claim 1, further comprising the step of
determining the degree of wind between the weapon and the target,
and adjusting the optical scope for the determined wind and
ballistics characteristics of the projectile.
7. The method of claim 6, wherein the optical scope is adjusted for
wind electronically and in communication with the image
stabilization device.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation-in-part and claims the
benefit of nonprovisional patent application Ser. No. 11/076,340
filed Mar. 8, 2005.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
[0002] Not applicable.
THE NAMES OF THE PARTIES TO A JOINT RESEARCH AGREEMENT
[0003] Not applicable.
INCORPORATION-BY-REFERENCE OF MATERIAL SUBMITTED ON COMPACT
DISC
[0004] Not applicable.
BACKGROUND OF THE INVENTION
[0005] 1. Field of the Invention
[0006] This invention relates to methods for optical stabilization
and movement compensation to improve the accuracy of small arms and
similar systems.
[0007] 2. Description of Related Art
[0008] A significant limitation of shooting accuracy is presented
by unsteadiness of the firearm. Bench-rest competition shooters
employ stable platforms for their rifles to remove this source of
motion. However, most other shooters must be content with imperfect
supports for their firearms. For example, a standing shooter
hand-holding a rifle results in a relatively unstable condition,
and most shooters place the rifle in contact with a fixed object,
such as a tree, bipod, or other stable platform. With accurate
rifles capable of accuracies of better than one minute of angle or
about one inch per hundred yards, even slight movements of the
rifle can lead to inaccuracies far in excess of the capability of
the rifle. Even a shift of only 0.01 inch by the muzzle of the
rifle can generate a significant inaccuracy in perfect shooting
conditions. Moreover, factors such as wind, the shooter's
breathing, and heartbeat can generate deviations in aim which will
adversely affect the point of impact of the bullet. In a combat or
hunting context, the shooter's physiological responses to stress or
excitement can significantly worsen the motion associated with
holding an imperfectly-supported rifle.
[0009] The motion or shake that causes shooting inaccuracy also
presents a visual problem. High-powered riflescopes magnify the
motion, thus blurring the image. This makes it difficult to detect,
acquire, and identify targets. Oftentimes, a shooter might prefer a
higher-powered rifle scope for accuracy, except that the shaky
image in actual use makes such higher magnification impractical.
Additionally, the effect of mirage produced by atmospheric
convection currents viewed over large distances can further
complicate the aiming process and introduce undesirable
inaccuracies.
[0010] With respect to difficulties in image clarity and movement,
optical stabilization for cameras and binoculars has seen great
commercial success. Moving a lens to keep the image stable and
centered as the device moves greatly improves these optical
devices. These moving lens techniques are very reliable,
inexpensive, and lightweight with low power requirements. Such
optical stabilization would be helpful to a shooter as he attempts
to identify and prepare to shoot at a target. However, when it
comes to improving accuracy, there are no viable optical
stabilizers for small arms, such as rifles and pistols, because
although the image is stable, the lens train and the barrel
continue to move. In practice, the shooter quickly identifies his
target and centers the target in the stabilized image, but he still
has no way of knowing when the barrel is aligned with the target.
The barrel continues to move relative to the stabilized image due
to unsteadiness in the position due to involuntary factors such as
heartbeat, breathing, and muscular activity.
[0011] Specifically, a bullet fired at the precise instant that the
moving barrel is exactly aligned with the target will always miss
the target. Under those conditions, the moving barrel necessarily
imparts movement to the bullet that will carry it away from the
target. Skilled shooters sometimes acquire a rhythmic pattern with
the barrel and pull the trigger at the right moment for the
imparted barrel motion to bring the bullet into contact with the
target when it arrives. Many hours on the range give them the
"feel" for this effort at different ranges, but it is an imprecise
solution to barrel movement, reflecting the need to compensate for
movement that can never be completely eliminated. Ideally, a barrel
movement compensation system, such as that presented herein, could
track the position of the barrel relative to the stabilized image,
and then release the firing mechanism at a calculated moment for
the bullet to contact the target at the end of its flight. The
result would be greater accuracy, as well as easier identification
and alignment with the target prior to taking the shot.
[0012] Many attempts have been made to increase the accuracy of
weapons, from small arms to heavy artillery. For weapon systems
where optical acuity, bulk, weight, and power consumption do not
appear to be concerns, it has been proposed to employ a
gyroscopically-stabilized television image as a fire-control
sighting system for a weapon on a moving platform to provide a
still image. This is described in U.S. Pat. No. 3,659,494 to
Philbrick et al. The Philbrick system projects an image of the
target on a photodetector, which converts the image into an
electronic signal. An electron beam regenerates the image on a
phosphor screen that is viewed by the user. The regenerated image
is stabilized by a facility that shifts the electron beam based on
gyroscopic inputs. While apparently suitable for aiming large
weapon systems, it does not appear to be suitable for applications
where a high quality image, and small size, low weight, low cost,
and simplicity are desired. Moreover, it appears unsuited to adapt
to existing rifle scopes.
[0013] The Philbrick patent further describes the system applied to
a weapon with an electronic trigger system, so that the sighting
system itself automatically sends an electronic signal that fires
the weapon when the sight is in a neutral or "home" position in
which the image is not shifted, unless the user inhibits firing by
releasing pressure on a trigger solenoid. Thus, the Philbrick
system is further unsuitable for adaptation to convention rifles
using mechanical triggers.
[0014] The present invention addresses all of the foregoing
concerns and difficulties attributable to movement of the firearm.
By controlling the release of the firing mechanism instead of
firing at the right position, the invention eliminates complex
controls required with systems that directly operate the firearm.
In other words, the firearm will only fire under the simultaneous
occurrence of two conditions: (1) the trigger is pulled, and (2) a
release signal is received from the compensation system upon a
calculation that the bullet will intersect the target at the end of
its time of flight. This method allows the shooter to identify and
aim with a stable image of the target using a conventional optical
stabilization system, select that target by pulling the trigger,
and the system releases the firing mechanism when the motion of the
barrel imparts the correct motion to the bullet so that it contacts
the target at the end of its time of flight using information from
that same optical stabilization system.
[0015] Thus, the present invention provides an inexpensive and
simple way to overcome the otherwise unavoidable problems due to
movement of the shooter and the firearm. Also, the invention
resolves issues that have historically kept optical stabilization
out of the small arms market.
SUMMARY OF THE INVENTION
[0016] A method is provided for stabilizing an image through an
optical scope and compensating for movement of a weapon directing a
projectile along a line of sight, comprising: providing an image
stabilization device for an optical scope mounted on a weapon,
wherein the image stabilization device includes a sensor to detect
motion of the weapon; providing a trigger release device
operatively connected to a trigger on the weapon; detecting
movement of the weapon by the sensor; generating an output signal
from the sensor, wherein the output signal corresponds to the
position and velocity of the weapon in a plane perpendicular to the
line of sight; processing the output signal to determine an optimal
release period, and then generating a release signal during the
release period; and using the release signal to activate the
trigger release.
[0017] In a preferred embodiment, the release period is determined
based upon an accuracy selection predetermined by a user.
[0018] In a further embodiment, the method further comprises
providing a trigger pull detection device adapted to determine if
the trigger has been pulled by a user; and using the release signal
to activate the trigger release only if the trigger pull detection
device indicates that the trigger has been pulled.
[0019] Optionally, the method may further comprise determining the
range of a target, and adjusting the optical scope for the
determined range and ballistics characteristics of the projectile.
Preferably, the optical scope is adjusted electronically by a
rangefinder in communication with the image stabilization
device.
[0020] Also, the method may further comprise determining the degree
of wind between the weapon and the target, and adjusting the
optical scope for the determined wind and ballistics
characteristics of the projectile. Preferably, the optical scope is
adjusted for wind electronically and in communication with the
image stabilization device.
BRIEF DESCRIPTION OF THE DRAWINGS
[0021] For a further understanding of the nature, objects, and
advantages of the present invention, reference should be had to the
following detailed description, read in conjunction with the
following drawings, wherein like reference numerals denote like
elements.
[0022] FIG. 1 is a side view of a rifle and mounted scope.
[0023] FIGS. 2A, 3A, and 4A are sectional side views of the scope
of FIG. 1.
[0024] FIGS. 2B, 3B, and 4B are viewfinder images through the scope
of FIG. 1.
[0025] FIG. 5 is a side view of the operation of one embodiment of
the invention.
[0026] FIG. 6 is a sectional side view of the embodiment of FIG.
5.
[0027] FIG. 7 is a schematic view of an idealized and stable lens
focused on a target.
[0028] FIG. 8 is a schematic view of a lens in motion to the left
and attempting to center on a target.
[0029] FIG. 9 is a schematic view of a lens in motion to the right
and attempting to center on a target.
[0030] FIG. 10 is a schematic view of a lens position centered on a
target.
[0031] FIG. 11 is a schematic view of the lens of FIG. 4 moving to
a new position to compensate for movement of the firearm.
[0032] FIG. 12 is a schematic view of the lens of FIG. 4 moving to
another position to compensate for further movement of the
firearm.
[0033] FIG. 13 is a schematic diagram showing the relative
positions of a target, the lens, and the point of aim when no
firearm movement is present.
[0034] FIG. 14 is a schematic diagram showing the relative
positions of a target, the lens, and the point of aim when the
firearm is in a first motion.
[0035] FIG. 15 is a schematic diagram showing the relative
positions of a target, the lens, and the point of aim when the
firearm is in a second motion.
[0036] FIG. 16 is a schematic diagram showing the effect of firing
when the moving firearm approaches the target, and the effect of
firing when the moving firearm is aligned with the target.
[0037] FIG. 17 is a schematic diagram showing a series of firearm
motions which are taken into consideration before indicating a
trigger release.
[0038] FIG. 18 is a flowchart depicting the sequence of events
prior to activation of the trigger release signal.
DETAILED DESCRIPTION OF THE INVENTION
[0039] Before the subject invention is further described, it is to
be understood that the invention is not limited to the particular
embodiments of the invention described below, as variations of the
particular embodiments may be made and still fall within the scope
of the appended claims. It is also to be understood that the
terminology employed is for the purpose of describing particular
embodiments, and is not intended to be limiting. Instead, the scope
of the present invention will be established by the appended
claims.
[0040] In this specification and the appended claims, the singular
forms "a," "an," and "the" include plural reference unless the
context clearly dictates otherwise. Unless defined otherwise, all
technical and scientific terms used herein have the same meaning as
commonly understood to one of ordinary skill in the art to which
this invention belongs.
[0041] Optical Stabilization
[0042] Prior to describing the movement compensation methods that
are the focus of the present invention, it is helpful to understand
the basic functions of conventional or existing image stabilization
technology. Optical stabilization consists of sensors that detect
the left-right and up-down movement of the optical device being
stabilized. In other words, motion of the device is detected in a
plane perpendicular to the line of sight. In response to the
detected motion, the device moves a lens to intercept the light
from the image and return it to the center of the lens train. This
lens is moved proportionally to the movement it detects in the
optical device. Consequently, the movement of the lens is also
proportional to the movement of the device. The position of the
correcting lens with respect to the stable image is a direct analog
of the position of the device with respect to the stable image.
[0043] Sampling the position of the lens with respect to the
stabilized image is exactly the same as sampling the position of
the device with respect to the stabilized image. In the case of a
telescopic sight or optical scope on a weapon, when the stable
image is on the target, the lens position is the position of the
telescope, and consequently, the position of the weapon barrel with
respect to the target.
[0044] Movement Compensation
[0045] Sampling the lens position (information developed in
stabilizing the image) at a regular rate (e.g. 1 ms), the speed and
direction of the lens is determined. Its future position can be
calculated for any time interval. When the lens is centered on the
image, the telescope and the barrel are centered on the image (i.e.
target). The lens and its movement are an exactly proportional
analog of the weapon barrel movement. Calculations of the lens
movement will show where it will be at the end of a time interval
equal to the Time To Target. For the purposes of this invention,
the Time to Target (ITT) is equal to the Time of Flight (TOF) of
the ammunition used, plus the Lock Time of the weapon used. The
Lock Time is the amount of time required from the release of the
trigger until the ignition of the gunpowder propelling the bullet
from the barrel. Such calculation of the lens movement also shows
where the barrel will be pointing at that time, as well as where
the sideways motion of the barrel, at its release, will have
carried the bullet.
[0046] Release of the trigger (or whatever applicable firing
mechanism is involved) when the calculation determines the lens
will center at the end of the Time To Target, means that the
sideways motion imparted by the barrel to the bullet will carry it
to the center of the stabilized image, the "bull's eye" (i.e., the
target if the trigger is pulled), when it arrives at the target at
the end of its Time To Target.
[0047] To designate the target (i.e., in the stabilized image), the
trigger is pulled against a restriction. When the calculated future
position of the lens will be centered at the end of the designated
Time To Target, the firing mechanism is released, and the bullet
exits the barrel with imparted motion that carries it to the center
of the image.
[0048] First, in the following figures, namely FIGS. 1-6, the
present invention will be described broadly with respect to
generalized rifle, scope, and image stabilization device. Then, the
more detailed methods for movement compensation will be described
with respect to FIGS. 7-18.
[0049] FIG. 1 shows a rifle 10 with a receiver 12 providing a
frame, a barrel 14 connected to the receiver and defining a barrel
axis 16. A stock 20 is connected to the receiver and partially
encompasses a trigger mechanism 22, leaving exposed a trigger lever
24. A telescopic rifle sight or riflescope 26 is secured to the
receiver by way of scope mounts 30. The scope has an elongated
tubular housing 32 with an enlarged forward portion housing an
objective lens 34, and a rear portion housing an eyepiece lens 36.
(All lenses are shown in simplified form instead of the preferred
multiple element arrangements.) A user 38 views an image of an
intended target from the rear of the eyepiece. A prismatic optical
element 40 is positioned between the objective and eyepiece lenses,
and is shifted vertically and horizontally by adjustment knobs 42
to shift the image to coincide with a bullet's expected point of
impact, with adjustments for elevation due to bullet drop based on
distance, and for windage due to cross winds. The scope defines an
optical axis 44.
[0050] At the front end of the scope, forward of the objective lens
34, is positioned a vibration reduction or image stabilization
device 46. As shown in FIG. 2A, the device 46 is in the form of a
transparent prism 50 with a flat front surface 52 and flat rear
surface 54. A liquid-tight bellows 56 connects the transparent
plates that provide the front and rear surfaces, and a transparent
index-matched fluid fills the volume defined by the plates and
bellows. This enables the front and rear surfaces to be angled with
respect to each other by the motivation of actuators (not shown)
about the periphery of the plates. The prism may provide any of a
range of angular offsets between the plates, with the direction of
the offset being in any direction. This provides the capability of
providing a device for deflecting or refracting a ray of light by
any amount up to a maximum deflection angle, in any direction with
respect to the optical axis 44 of the scope 26. FIG. 2A shows the
prism in the neutral position in which the plates are parallel to
each other and perpendicular to the scope axis 44. Both plates may
move as shown, or one may be fixed with the other movable. Any
alternative image-shifting system may be employed.
[0051] The stabilization device operates in response to angular
motion of the rifle to which it is fixed, both in the pitch
direction (muzzle up and down) and the yaw direction (muzzle
right-left). Gyroscopic, inertial, optical or other angular motion
sensors operate in each of the two axes to indicate to device
circuitry the angular displacement of the stabilization device.
Because the position of the device is fixed in relationship to the
barrel, movement of the device is effectively equal to movement of
the barrel. In response, the prism instantaneously and continuously
adjusts the angle and magnitude of shift to generate a beam
deflection equal to the sensed angular displacement, based on
conventional optical formulae. Such devices are well known in
binoculars and video cameras to provide stable images. Typically,
the devices are limited to sensing and correcting for only small,
rapid angular movements, and not large, slow and sustained
movements. In alternative embodiments, any other type of
stabilization system may be employed, as long as it is a
transparent system that transmits the image without degradation. A
lack of image degradation facilitates accurate target detection and
identification. Further, a transparent system keeps the image of
the target at a long or essentially infinite distance, unlike
stabilization systems that project or generate an image on a screen
of the device. Accordingly, conventional rifle scopes that are
designed for viewing distant images may be employed with such
zero-magnification transparent devices.
[0052] Because the angular displacements that are of concern to
shooters are extremely small (on the order of minutes of arc), the
prismatic deviations needed are very small, so that there is no
concern with chromatic aberrations degrading the image. Moreover,
the vibrations associated with rifles, and attributable to human
movement, are much longer period than those of compact camcorders
and binoculars, owing to the relatively substantial weight and
moment of inertia of an elongated rifle. Thus, the stabilization
system may be tuned to filter out vibrations with a frequency on
the order of one second or less; i.e. higher frequency
vibrations.
[0053] In FIG. 3A, the system is shown in a condition in which the
rifle is in an elevated condition with the muzzle momentarily
elevated unintentionally due to the unsteadiness of the shooter. In
FIG. 4A, the rifle is in a depressed elevation. In both cases, the
angle is greatly exaggerated for clarity, with the actual angle
being less than one degree, compared to the illustrated angle of
about ten degrees. The prism is flexed in the appropriate
orientation (illustrated with exaggerated flexure) to take the
horizontal incoming ray, and deflect it to continue down the
optical axis of the scope. This may also be thought of as taking
the target aiming point as perceived by the user, and shifting the
prism as the rifle moves to keep the same target point at the same
position in the field of view. While this occurs, the rifle bore
and actual point of impact shift with the unsteady rifle, even
though the image appears steady.
[0054] Feedback is provided to the user about the degree of shaky
deviation from the nominal point of aim. FIG. 2B shows the field of
view 60 seen by the user. A target 62 is seen, and a first reticle
shown as crosshairs 64 that remain fixed in the field of view. The
image may be shifted in the field of view in a conventional manner
using the knobs 42 to zero and calibrate the scope, and to adjust
for elevation and windage based on distance and wind. This shift is
independent of the stabilizing shift generated by the prism. In
FIG. 2B, the prism is in the neutral position corresponding to FIG.
2A. The intersection of the cross hairs of the first reticle 64
reflects the actual point of impact (assuming a zeroed scope with
properly adjusted knobs for the target distance.)
[0055] A second reticle 66 in the form of a circle is centered on
the first reticle. The second reticle indicates the actual point of
aim, and moves as the rifle shakes. The second reticle's movement
is in a direction, magnitude, and velocity to correspond to the
rifle shake. In FIG. 3B, the upward deviation of the rifle is
illustrated by the second reticle circle 66' being shifted upward
out of alignment with the first reticle, and in FIG. 4B, the
downward deviation of the rifle is illustrated by the second
reticle circle 66' being shifted downward out of alignment with the
first reticle. The second reticle may shift in any lateral or
angular direction based on angular rifle motion in any direction,
not just the vertical deviations shown for simplicity in FIGS. 3B
and 4B.
[0056] The neutral condition shown in FIG. 2B is further indicated
by the second reticle 66 being illuminated. The neutral condition
is defined as device deflection angles less than a selected
threshold, i.e. the size or diameter of the second reticle 66. This
threshold may vary depending on the application, and may be varied
by user by an input device (not shown) that connects to control
circuitry. For maximum accuracy under stable and controlled
conditions, the tolerated deviation may be a minute of arc. For
closer range hunting in unstable conditions, a much wider range of
deviation may be tolerated and still be considered adequately "on
target" and thus in the neutral condition to generate the visible
feedback. The threshold may be programmed upon manufacturing for a
particular application, or may be settable by reprogramming or an
input such as a dial or knob in the field by the user.
Alternatively, the reticle may be located within the image shifting
prism system, so that motion of the prism inherently adjusts the
apparent location of the reticle.
[0057] Feedback is also provided in the form of a trigger block
mechanism to be discussed below in the context of the alternative
embodiment. Such a mechanism serves to prevent discharge of the
firearm except when the sight accurately reflects the point of
impact on the target, so that a user is not deceived by the first
reticle being on target when the rifle is shaking off target. A
user may apply pressure to the trigger, but it has no effect until
the moment that the system indicates a neutral condition, in which
case the trigger block releases to allow trigger movement.
[0058] To provide feedback, the circuitry that calls upon the prism
to shift has an output that transmits a signal, or which is
switched to a voltage potential, when the prism deviation is less
than the preselected threshold. This enables the user to overcome
inherent instabilities without needing to time a shot by
anticipating a moment of alignment, which risks jerking the trigger
and misaligning the rifle from the target before the bullet exits
the muzzle. For instance, a shooter in a stable prone position may
still experience a cyclic motion of the point of aim due to
breathing. Even with breath control and holding one's breath when
taking the shot, heartbeats can cause a cyclical motion. As the
user observes the cyclic motion, typically a diagonal or elliptical
path of the point of aim, the stabilization system maintains a
steady image, and the shooter readily holds the first reticle's 64
crosshairs on the desired target point (which appears steady.) The
cyclic or other motion is indicated to the user by the motion of
the second reticle 66, which may follow the diagonal or elliptical
path. The shooter ensures that the path crosses through the neutral
point, so that the circle coincides with the cross hairs
periodically, causing the second reticle to illuminate regularly.
When such a cycle is established, the shooter may apply pressure to
the trigger, and the rifle will discharge when the next neutral
condition occurs. This provides for enhanced accuracy, because the
shooter does not know when the discharge will occur. Being
surprised by the exact moment of discharge prevents and makes
impossible the flinching that causes many shots to miss.
[0059] A shooter in very unsteady conditions may find that it is
difficult to get regular indications of a neutral condition. In
such instances, the shooter may adjust the threshold of accuracy,
or find a more stable position or support to make shooting more
accurate. Thus, the system prevents shots that may be dangerous to
bystanders (in the case of a police marksman) or inhumane to
game.
[0060] The second reticle movement is provided by a transparent LCD
display with a sufficient resolution of pixels, so that the circle
may be displayed in any location in the field of view. In
alternative embodiments, the reticle may be moved by actual motion
of the reticle or of an optical element that projects the reticle
into the field of view. As shown in FIG. 2A, the first reticle 64
is positioned in the first focal plane of the rifle scope. This is
the position at which the objective lens focuses the nearly
parallel rays from the image of the distant target. Thus, the
reticle 64 appears sharp when the image appears sharp. The element
40 refocuses the rays to the second focal plane, where the second
reticle 66 is positioned. This is the focal point of the eyepiece
36, which transmits a sharp image of both reticles and the image to
the user 38. In alternative embodiments, the reticles may be
switched to occupy the opposite focal planes, or a single reticle
having cross hairs, and an LCD or other means for displaying a
moving circle may occupy a common focal plane.
[0061] FIG. 5 shows the effects of bullet drop with respect to the
rifle 10. The bore axis 16 extends straight from the muzzle of the
barrel. In practice, the effects of gravity cause the bullet 70 to
drop as it follows the bullet path 72 on approach to the target 74.
To provide for accurate aim, the line of sight 76 of the riflescope
26 must be angled downward with respect to the bore axis. This
downward angle is different from the slight shift provided by the
prism 50 to avoid shake as discussed above, because the downward
angle must be sustained. In conventional scopes, this is achieved
by adjustment of the lens or prism element 40 using calibrated
knobs that are marked with distance (for a given standard
ammunition round) or simply the angular deviation in arc-minutes.
Such deviations may be on the order of 100 arc minutes for long
distance shooting, and thus are about an order of magnitude or more
greater than the deviations caused by unsteadiness.
[0062] In the alternative embodiment shown in FIG. 6, a riflescope
aiming system 80 employs the same prism 50, which is connected to
control circuitry 82 and positioned forward of the objective lens
34, which is on axis with the eyepiece lens 36. In this embodiment,
the element 40 is absent, as are the knobs that adjust it. A single
focal plane is provided for a single reticle 84, which is at the
common focal point of the objective and eyepiece. All adjustments
for windage and elevation are made by the prism 50, which is the
only moveable element in the system (other than focusing or
collimation adjustments used on any telescope without firearm
functionality. These adjustments may be made even if the prism were
not employed for shake reduction, and though both features are
preferably usefully combined. In a simple case, input knobs (not
shown) may be provided for the user to input the target distance or
elevation adjustment, as well as any windage correction. However,
in the preferred embodiment, either or both of these are
established by electronic means.
[0063] A rangefinder 86 is connected to the circuitry 82, and
determines the distance to the target, and transmits range data to
the circuitry, so that the expected bullet drop can be calculated.
Based on this bullet drop, the prism shifts by the appropriate
amount. Similarly, and optional windage adjustment may be provided
by entering wind speed or direction, or employing a remote
anemometer 90 that transmits via radio or other means the wind
direction and speed. The wind information is received by a radio
receiver 92 on the scope, and is electrically connected to the
circuitry. The circuitry may have substantial computing power, so
that multiple anemometers may be used for more precision.
[0064] For more precise calibration, or to adjust to non-standard
ammunition or powder loads, the system may be calibrated by
shooting at a variety of known distances. At each distance, the
user may indicate the deviation from the system's expected target
point by inputting to the system the targeted point, and also the
actual point of impact, so that the system can detect the
difference in angle between the two points, and compensate. This
may be done by aligning one reticle with the intended point of aim,
and adjusting the other reticle to the actual point of impact. With
several distances established, the system's computer circuitry may
interpolate a more accurate bullet path for all distances. The
system may interface with a separate computer where extensive user
input is required, and to avoid an excessively complicated or bulky
interface on the scope, and the system and computer may communicate
by cable or any wireless means.
[0065] In addition, the unit may receive or be entered with more
general information about prevailing winds, which would provide
less useful information, but would be useful in battlefield
conditions where troops are unable to readily ascertain wind
information. An advanced system may employ an external system such
as airborne doppler radar to more precisely map wind patterns in
real time, and to provide downloadable information to a soldier
whose system provides a GPS location to upload to the radar system
to gain local wind information, including wind patterns between him
and the intended target. The system may also employ an elevation
transducer that provides information to the circuitry about the
angle of elevation or depression of the barrel, so that the image
may be shifted to compensate for the effects of shooting at such
angles.
[0066] FIG. 6 shows in detail a trigger block system that is
employed in either illustrated embodiment. A solenoid 94 having a
piston 96 is electronically connected to the control circuitry 82
(which is employed by all embodiments.) Normally, the cylinder is
extended to block the path of the trigger lever 24 to prevent
firing. When the system is in the neutral position, the circuitry
applies a voltage, and the piston retracts. Depending on intended
usage, when power is lost, the solenoid may be selected to default
to the safe position (such as for a hunting rifle) or the enabling
position (such as for military use). The trigger block is designed
for low friction interaction with the trigger lever (preferably by
a trip mechanism employed in triggers and not the sliding piston
shown) so that pressure on the trigger lever by a ready shooter
does not inhibit retraction of the piston. This enables the shooter
to employ the "squeeze when ready" technique, and await the moment
of discharge while keeping the crosshairs (or whatever pattern
desired for the first reticle) on the target point. In an
alternative embodiment, the trigger block may interact with any
suitable element in the trigger mechanism to inhibit and permit
firing.
[0067] In alternative embodiments, firearms employing electronic
triggers and using ammunition with electrically activated primers
may use the same system, but with the neutral signal enabling the
electronic means of firing. For instance, the stabilization system
may be added to a riflescope to the rear of the eyepiece, in which
case the scope crosshairs would move with rifle and prism movement,
and the second reticle would remain stationary. In addition, the
system may be employed in conjunction with any aimed weapon,
including handguns, bowed weapons, beam weapons, and any military
projectile-expelling weapon.
[0068] This disclosure is made in terms of preferred and
alternative embodiments, and is not intended to be so limited. For
instance, the several different features and alternatives may be
implemented individually, or any of a wide range of combinations.
Some of these options are discussed below.
[0069] The image stabilization technology discussed above with
respect to the preferred embodiment may be substituted for by other
optics, magnetic stabilization or mechanical isolation of the
optics from the housing and still work. The system may be
integrated in new product designs, or retrofitted to existing
scopes and rifles. The feedback transducer reticle may be a painted
or etched circle, crosshairs or other reticle design on a flat
glass ahead of the stabilizing system in add-on configurations on
the front of the scope or to the rear of the stabilizing system in
add-on configurations to the rear of the scope. The trigger block
can receive the signal by wire or wireless (using the keyless
systems from the car industry or similar systems). For versions
incorporating bullet drop and windage correction, the operation of
the stabilizing system never changes. Instead, the location of the
neutral or zero correction point is changed in the sensing system
so that the signal is sent when the elevation is such that bullet
drop is compensated for.
[0070] The preferred embodiment shows and describes an internal
trigger block. For many applications, it will instead be desirable
to have an add-on external trigger block that requires no
modification of the firearm, just as an add-on stabilizer requires
no modification of the telescopic sight. The blocking mechanism
would attach to the bottom of the trigger guard behind the trigger.
It would be installed to touch the back of the trigger lever and
secured with set screws (or other means). It would prevent the
trigger from traveling backwards until the zero adjustment signal
is receiver at which time it releases. Pressure is applied to the
trigger by the shooter when his sight pattern is the way he wants
it. He moves the weapon to align the moving reticle with the
stabilized one and when he accomplishes this the signal is given,
the block releases and the weapon fires. A second part of the block
remains in front of the trigger and resets the block when the
trigger is released and returned to "ready" position. With an
external block system there would be no need for adjustment for
different firing systems.
[0071] All reticle adjustment directions are given as examples, and
may be reversed depending on common practices and simplicity.
[0072] An exemplary stabilizing system would be the Canon VariAngle
Prism system packaged with controller and battery in a short, wide
tubular barrel with front and rear non-magnifying lens. An
additional circuit would detect the instances in which there is no
correction by the stabilizing optics and be capable of sending out
an electrical signal. A battery condition indicator and an on/off
switch would complete the standard package.
[0073] This package would attach to the front of the barrel of the
telescopic sight. The attachment would use an adapter selected to
fit the type of attachment (front or rear) and the size of the
front of the telescopic sight. The front of the adapters will
accept the standard screw-in component of the stabilizing
package.
[0074] One type of adapter would slip over the barrel and be moved
rearward until the rear non-magnifying lens was in contact with the
front lens of the sight. It would then be tightened at the rear
with a long section that would hold the alignment of the stabilizer
and sight. Another type of attachment would unscrew the front
shading lens and replace it with a screw-in adapter chosen to fit
the barrel. An internal receptor will allow the shading lens to be
reattached inside the barrel of the stabilizer if that is
desirable.
[0075] A reticle (circle, crosshairs, dot, or other design) would
be etched in front of the stabilizing optics to provide the
feedback of the weapon position in relation to the stabilized
image. This reticle would be lighted from below with a small bulb
that would shine when the "zero correction" signal is received.
[0076] Another version would incorporate a range finder (optical or
laser) in the stabilizer package. The optical range finder would be
connected to the stabilizer controller to communicate the range.
The communication of the range would cause the controller to send a
"zero correction" signal at a higher aiming point than the neutral
point to compensate for bullet drop at that range. The feedback
reticle would be adjusted down to indicate that new "zero
correction" signal position. This would require the shooter to
raise his weapon to bring the feedback reticle in line with
cross-hairs and consequently compensate for the bullet drop at the
range shown by the range finder.
[0077] A calibration of this range input to the controller would
cause the range detected to move the signal point to the
appropriate setting that offsets the bullet drop. It would be done
in a "calibration mode". In this mode, a target is set up at a
normal range for the usage expected. The target is acquired with
the stabilizer in operation. The range is detected by the range
finder; the bullet is fired and the bullet drop at this distance
from the target is noted. The calibration knob (or other method
such as ring, button, etc.) is operated to lower the feedback
indicator circle so that the center of the circle is even with the
bullet strike. Now the range is known and the amount of bullet drop
at that range is known, and they are unique to that
weapon/ammunition combination. Each time the range is detected by
the range finder those values are used to determine the change in
the position of the "zero adjustment" signal that will just allow
for that bullet drop.
[0078] As a practical matter the calibration of the bullet drop
adjustment would work best with more than a neutral setting of the
telescopic sight range. This feature could be used in conjunction
with different telescopic sight settings. By having a selector on
the stabilizer the weapon could be calibrated at 100 yds, 400 yds
and 600 yds, for example, and the range selected in the field would
have exact range settings through the disclosed system. Each ratio
used to adjust for bullet drop would correct at the telescopic
sight setting for exact point of impact information. In the prior
art, with high magnification, the movement of the sight reticle
from shooter body instability was greater than the gross adjustment
of the range. Now with stabilized optics, the precise adjustment of
range is useful, and the disclosed system delivers it.
[0079] The amount of bullet drop for a particular weapon/ammo
combination is due to the force of gravity and factors of velocity
and bullet drag. The windage used in sighting is an adjustment for
the force of the wind. Once the ratio of range/bullet drop for one
force (gravity) is known, the ratio of bullet deflection for
another force (wind) can be automatically adjusted for. The force
of gravity was allowed for by a ratio of bullet drop distance to
range distance. All that is needed now is to detect the force of
the wind vector that is perpendicular (other vectors are not
important) to the line of sight. By applying a constant relating
wind force amount to gravity force the adjustment for wind is
available.
[0080] A tube (or tubes), perpendicular to the axis of the sight,
which detects the direction and velocity of the crosswind vector
provides the information needed for an indicator for manual
adjustment or automatic adjustment based on the range and
weapon/ammo combination. A single tube with a two way turbine that
detects speed and direction fill this requirement. Another simpler
design would consist of two opposite facing venturis with pressure
detectors.
[0081] Gravity is the same all the way to the target but wind is
not necessarily the same all the way to the target. This
information could be displayed as an indication to be used as the
basis of manual windage adjustment. The shooter selects windage
adjustment with that indication as his basis and his estimates of
wind differences between him and the target (e.g. shooting across a
valley). His adjustment can be made in the stabilizer package or in
the windage adjustment on the telescopic sight.
[0082] This package that attaches to the front of the rifle scope
may be a stand alone product with several additional attributes
available. The "zero correction" signal in the basic single
component package is visual. The main advantages are the additional
visual details available with the stabilized image and a more
accurate shot.
[0083] Hyper accuracy at high magnification or with unstable
platforms (e.g. pistols or archery versions) is available to the
shooter with the trigger block mechanism added for these additional
applications.
[0084] For the add-on system, a small, low power, high frequency,
radio transmitter that transmits an encoded signal when the "zero
correction" situation is detected is added to the device that
attaches to the front of the telescopic sight. A small
battery-powered receiver, tuned to this encoded signal, is packaged
with a simple release mechanism that is coupled to a trigger block
device. That device is attached to the trigger guard with the
"blocking tang" behind the trigger. It slides forward along the
guard until it contacts the trigger. When contact is made the
trigger block is fastened in place. The trigger is now blocked from
operation until two things happen: the shooter applies pressure on
the trigger and the encoded signal indicating "zero correction"
condition is received by the blocking mechanism.
[0085] The shooter applies pressure on the trigger when the sight
picture is as he wants it and moves the weapon so the feedback
reticle and the telescopic sight reticle coincide. This situation
causes the transmitter to broadcast an encoded signal (similar to
the system in an automobile keyless entry system). The encoded
signal prevents different systems from interacting in the same way
a keyless entry system only opens its door and not all those within
range. When the encoded signal is received by the trigger block
mechanism the block is released and the pressure by the shooter
fires the weapon. Since the shooter does not know when the release
is coming there is no trigger jerk and accuracy is even higher than
with the single add-on component. There is only a receiver and a
release mechanism so its power requirement is low.
[0086] Besides the trigger block tang that sticks up from the
trigger guard behind the trigger there is another tang that is
lying flat against the trigger guard in front of the trigger. When
the trigger mechanism is released and the blocking tang is pushed
to lie flat against the trigger guard under the engaged trigger the
reset tang is moved perpendicular to the trigger guard in front of
the trigger (now at the rear). This "reset tang" engages the
trigger as it returns to firing position and resets the blocking
mechanism. Now the reset tang is lying along the guard and the
block tang is locked against the rear of the trigger, ready for
another target.
[0087] One very useful application of the system would be the
addition of the stabilizing package to an archery mechanical string
pull device. A low power sight with stabilizing, ranging and
windage capabilities would have an even greater impact on the
accuracy in archery. The effects of the two forces (gravity and
wind) are even greater on an arrow than on a bullet. The trigger
release could be wired to directly receive the "zero correction"
signal to release the mechanical string pull's trigger.
[0088] This arrangement also allows the sight to be positioned with
the eyepiece at the shooters aiming eye, also improving accuracy.
Optics can connect the eye with the arrow line of sight even though
the line of sight is inches below the eyepiece level. Ranging,
windage, jerk-free release and comfortable sight position would
provide significant advantages for an archery application. Similar
advantages can be achieved with scoped pistols.
Methods of Operation
[0089] Although aspects of the invention have been explained in the
foregoing descriptions with respect to certain apparatus and
physical embodiments, further elaboration as to the operational
methods employed will assist those of ordinary skill in the art in
practicing the invention.
[0090] Specifically, a method is provided for stabilizing an image
through an optical scope and compensating for movement of a weapon
directing a projectile along a line of sight, comprising: providing
an image stabilization device for an optical scope mounted on a
weapon, wherein the image stabilization device includes a sensor to
detect motion of the weapon; providing a trigger release device
operatively connected to a trigger on the weapon; detecting
movement of the weapon by the sensor; generating an output signal
from the sensor, wherein the output signal corresponds to the
position and velocity of the weapon in a plane perpendicular to the
line of sight; processing the output signal to determine an optimal
release period, and then generating a release signal during the
release period; and using the release signal to activate the
trigger release.
[0091] In a preferred embodiment, the release period is determined
based upon an accuracy selection predetermined by a user.
[0092] In a further embodiment, the method further comprises
providing a trigger pull detection device adapted to determine if
the trigger has been pulled by a user; and using the release signal
to activate the trigger release only if the trigger pull detection
device indicates that the trigger has been pulled.
[0093] Optionally, the method may further comprise determining the
range of a target, and adjusting the optical scope for the
determined range and ballistics characteristics of the projectile.
Preferably, the optical scope is adjusted electronically by a
rangefinder in communication with the image stabilization
device.
[0094] Also, the method may further comprise determining the degree
of wind between the weapon and the target, and adjusting the
optical scope for the determined wind and ballistics
characteristics of the projectile. Preferably, the optical scope is
adjusted for wind electronically and in communication with the
image stabilization device.
[0095] As will be further evident from a consideration of FIGS.
7-18, the position of the stabilizing lens exactly defines the
position of the device with respect to the image. When the
stabilized image is on the target, the position of the stabilizing
lens exactly defines the position of the barrel with respect to the
target. The image stabilizing system and trigger block restrict
firing until the data defining lens position indicates that the
barrel position (with respect to the target) is correct. At that
point the restriction is released and the weapon fires with greater
accuracy than without the compensation. To summarize, the trigger
is not pulled by the shooter until the stabilized image is on the
target, although many release signals are sent as image data is
processed. The only signal that matters is the one sent immediately
after the trigger has been pulled by the shooter. The next firing
release signal received after the trigger pull allows the trigger
to fire the weapon.
[0096] The gyroscopic instruments within the image stabilization
system send position data to the microprocessor. The processor
positions the stabilizing lens accordingly. The lens is positioned
to refract the image to compensate for the barrel movement detected
by the gyros so that the image is held steady for the eye.
Stabilizing lens movement is the analog of barrel movement.
Therefore, when the stabilized sight is on target, displacement of
the lens from the zero X, zero Y position is the displacement of
the barrel from the target, as shown in FIG. 7 in terms of the line
of sight, and in FIG. 10 with respect to the image through the
scope. Detecting the position of the stabilizing lens can be done
more than one way. The most direct would be to read the position
instructions to the lens. Another way is to read positions from
gradient reticules on the lens sides as suggested in FIG. 10. By
sampling these positions at a known rate, the processor tracks the
barrel vector with respect to the target. The vector of each change
is calculated and extrapolated by the bullet time of flight (from
the ballistics data). The ballistics algorithm calculates the point
of impact taking into account the momentum imparted by the
barrel.
[0097] When this point of impact falls within the acceptable range
of values, a release signal is sent to the firing restrictor (or
trigger block). As explained previously, although many signals are
sent, if the trigger is not pulled against the restrictor, there is
no shot. The shooter pulls the trigger when the stabilized image is
on target, and the next release signal after trigger pull releases
the restriction, and the weapon fires. The barrel movement vector,
determined by the stabilizing lens vector, imparts the momentum to
the bullet that will carry it to the calculated point of impact,
e.g. the target, during the time of flight (TOF) of the bullet.
[0098] FIGS. 8 and 9 depict schematic views of a lens in motion to
the left and right, respectively, by operation of the image
stabilization device. As those figures indicate, deviations in the
lens position from the line of sight to the target are proportional
to the deviation of the barrel. In stabilizing the image, the lens
moves to redirect the eye as the barrel moves. So, the barrel is
centered on the target when the lens is centered. Thus, the output
signal from the image stabilization device is ideal in efforts to
center the point of impact on the target.
[0099] As suggested above, FIG. 10 depicts a schematic diagram of a
stabilization lens in its carrier. The numbered lines indicate
units of deviation of the lens from a centered position, and FIG.
10 shows a lens centered at X=0 and Y=0. In FIG. 11, as a result of
a hypothetical barrel movement, the lens has moved to redirect
light from the stabilized image in response to movement of the
barrel, which is positioned at X=-1 and Y=+1. Similarly, in FIG.
12, movement of the barrel has caused the lens to move to redirect
light from the stabilized image to a new position at X=+2 and Y=-2.
FIG. 13 depicts an image in which the stabilized lens and the
aimpoint are centered, such that the lens position is at X=0 and
Y=0, and the aimpoint is centered on the bullseye of the
target.
[0100] FIG. 14 and FIG. 15 depict images which correspond to the
lens positions shown in FIG. 11 and FIG. 12, respectively. Thus, it
can be seen that the actual location of the aimpoint and lens
positions are different, they are in fact proportional as described
above.
[0101] FIG. 16 depicts a composite image of the position of the
aimpoint in three positions prior to release of the trigger, and
showing possible points of impact. As the barrel moves due to the
conditions described previously herein, the aimpoint will also
move, such as in Positions 1, 2, and 3. Understandably, if the
weapon is fired when the aimpoint is on the target, while the
barrel is in motion, then the bullet will not impact the bullseye,
because it will travel to a location which is dictated by the
momentum imparted to the bullet when it leaves the muzzle.
Therefore, the critical aspect of the present invention is to
define a time, or release period, wherein the trigger block or
firing restrictor is released while the barrel is moving along a
path that will cross the bullseye. The exact time of release will
depend on several factors, but most importantly the TOF to the
target. In FIG. 16, the position of the aimpoint at Position 3 is
an example of an ideal time to activate the trigger release,
because the bullet will strike the bullseye, or at least in the
near vicinity more accurately than the shooter relying solely on
his own instincts.
[0102] FIG. 17 is another depiction of barrel movement in several
positions and the possible points of impact if the weapon is fired
in each case. Again, barrel movement is tracked by the
stabilization lens position. The present invention calculates the
barrel position to fire such that the bullet will impact the center
of the target at the end of its TOF. In practice, as the shooter
aims the weapon, the trigger is pulled by the shooter against the
trigger block which prevents firing. Only at the instant that the
calculation of the lens movement determines a proper position,
path, and velocity of the barrel is the trigger block released.
Upon release of the trigger, the weapon is allowed to fire the
bullet, resulting in a point of impact that is far more accurate
than other methods.
[0103] Finally, FIG. 18 depicts a typical flowchart showing the
sequence of events prior to activation of the trigger release
signal. As explained previously, any image stabilization device
which is capable of outputting an electronic signal may be used in
connection with the methods described, because the movement
compensation for the weapon is directly proportional to the
movement of the stabilizing lens. The present invention employs
that information, in combination with known ballistics of the
specific projectile, range, windage, and weapon characteristics to
determine the timing of a release period for the trigger release
operating on a trigger block.
[0104] In practice, a small thin film pressure switch may be
attached to the stock. When stabilization and compensation are
required, the thumb of the shooter moves to cover the switch and
begin operation. After the shot (or shots) the thumb slides down,
turning off the operation and conserving battery power. Signal
input control is necessary because many release signals are being
sent even when the trigger is not pulled, as explained elsewhere
herein. If input is not controlled, the relays would be opening and
closing constantly while the system is on. Such operation would
undesirably use battery power unnecessarily, and would present a
small but annoying clicking sound to the shooter. A pressure switch
prevents the release signal from getting through to the trigger
restrictor until the trigger is pulled. Only the next release
signal arriving after trigger pull operates the release relay to
conserve power and eliminate clicking.
[0105] Therefore, to summarize the fundamental operations of the
invention in accordance with the methods described herein, the
shooter first finds the desired target in the normal manner by
placing the target generally within the view of the scope, placing
the reticle on the desired location of the target. During this
first step, the image stabilization system would be turned off. In
one embodiment, the range to the target is entered into the
stabilization system manually and the scope is adjusted for range
and windage. In another embodiment, such adjustments can be made
automatically and electronically. The rate of fire parameter within
the system is set for the situation desired. When the general
location is determined, the shooter's thumb moves to the on-off
switch to turn on the stabilization system.
[0106] The invention then stabilizes the image, allowing for quick
and accurate identification of the target. Immediate acquisition of
the target in the stabilized image brings quick pressure to the
trigger. An instant later, the release signal is transmitted if the
compensation system determines that the X-component and Y-component
of the movement are within the predefined ranges. Upon transmission
of the release signal, the shot is fired accurately. If the
automatic ranging (bullet drop compensation) and windage correction
features are included, the shooter enters the range and wind force
manually and makes no other adjustments. The necessary corrections
are then made within the circuitry to compensate for the bullet
drop of the particular ammunition at this range. Similarly,
entering the wind vector in terms of percentage of gravity
automatically moves the reticle left or right to compensate for
windage. These features, coupled with a rangefinder/wind gauge
would serve to automate such adjustments.
[0107] Further Applications
[0108] One possible application of the present invention is to
weapons with a reflex sight such as a holographic sight or red dot
sight. These sights project an aiming reticle at infinity for quick
reflex shooting, usually using both eyes to aim. They are built
with zero magnification, because they are usually used for close
range shooting. They may be used with magnifying units available
with a swing mount behind the reflex sight. The magnifier can be
swung into play when needed and out of the way when the conditions
change. This allows the shooter to choose 2+ or 3+ magnification
for longer ranges. The magnifier can be stabilized identically to
the telescopic sight. One of its lenses could be mounted in a
module that moved to counter weapon movement so the image would
stay centered and still. It would be much easier to identify,
acquire and then designate the target with a trigger pull, and the
accuracy would be greatly enhanced by the present invention.
[0109] For example, in a typical field operation, a military patrol
may be in a small town to evaluate insurgent status. They run into
a fire fight at close range and engage with reflex red dot sights
with zero magnification. The enemy withdraws and takes up positions
100 to 200 meters from the original engagement. Their positions are
in civilian houses and behind civilian walls and doorways.
Optionally, the patrol could switch to automatic fire and put 20 to
30 rounds on each position with maybe a third of these effective,
but with great damage and danger to civilians and ammunition usage.
Alternatively, they could advance to reflex sight range, but with
greater danger. With the weapon equipped with movement compensation
devices employing the present invention, the troopers swing their
stabilized multipliers into position behind the reflex sights and
begin very accurate return fire. With every shot getting on target,
they quickly neutralize the target from a safer range, with much
less ammunition, and less civilian damage. They are able to engage
sooner, because their rangefinders adjusted for bullet drop
automatically. With the stable image, there was no mistaking
combatants from citizens, and the greater accuracy of the
semi-automatic fire used very much less ammunition.
[0110] Also, the greatest training expense for field troops is
marksmanship. The results of this expensive training is dismal in
actual combat. The present invention would make all troops equally
accurate at longer combat ranges, dramatically cut training time
and expense, and the training would carry over to combat.
[0111] With respect to law enforcement, the benefits are more
pronounced than the military. Target identification with a
stablized sight picture becomes critical when civilians and other
officers are involved. Controlled placement of the shot in field
conditions is available in hostage situations. Turning a
reflex-aimed pistol into a longer range telescopic sight weapon as
the situation warrants is another benefit that fits well with law
enforcement needs.
[0112] These same benefits accrue similarly to the hunter in the
field with quick, accurate identification and acquisition, exact
placement of the shot for a quick, clean kill, and bench rest
accuracy in field conditions. Firearms equipped with device
incorporating the present invention would extend their safe range
as the stabilized image allows for exact target identification and
precise shot placement.
[0113] Finally, optical stabilization, applied to a bow sight and
the sport of archery would revolutionize the field. The bow is even
less steady than a rifle or pistol, and there is no archery bench
rest. When the target is acquired, the string release device well
known to archers is squeezed, just as the trigger in a firearm.
Keeping the target centered in the stabilized image will insure a
hit, because the arrow/bow ballistics will release the arrow when
the position and movement are optimal. Again, the arrow will not be
released unless the string release device has been squeezed and the
release signal has been sent by the system.
* * * * *