Laser aiming device for weapons

A laser is attached to a weapon and its beam is aimed toward the target. The dot of laser light on the target is observed through a light filter which permits passage of light of the same wavelength as the laser light. The filter may also be removed from the line of sight to the target.

BACKGROUND OF THE INVENTION 
The present invention relates to an aiming device for any weapon that fires 
a projectile at a target which is in the line of sight from the weapon. 
More particularly, the invention relates to a laser aiming device which 
shines a laser beam on the target and enables a marksman to preview the 
area of anticipated impact of the projectile. 
Aiming a weapon is often difficult. The target sighting device, i.e., the 
gunsight of the weapon, must be placed at the marksman's eye, and 
especially with handheld weapons such as rifles and the like, this may not 
be a comfortable or steady position for holding or firing the weapon. 
Further, the usual procedures of sighting on a target and the designs of 
standard sighting devices greatly restrict the marksman's field of view of 
the target and, on occasion, time must be spent to locate the target in 
the sighting device. Additionally, a marksman may have to close one eye to 
adequately sight on a target, greatly restricting his field of view and 
rendering him unable to know about events taking place in his immediate 
vicinity. Conventional aiming devices do not permit the marksman or 
operator of the weapon to preview precisely the impact area of the weapon 
but only permit the marksman to visualize the general field of the target. 
As a result, aiming efficiency is rather low. The aiming efficiency can be 
improved with the help of specialized equipment, such as radar, which 
requires additional experienced personnel for its operation. Still 
further, weapons must often be fired at poorly visible targets, e.g., at 
obscure targets and under unfavorable weather conditions. Additionally, 
great speed of aiming and ease of aiming are both hard to attain with 
conventional aiming devices. 
Conventional weapon aiming devices are either optical and use front and 
rear sights, or they are infrared, or they are optical and mechanical or 
electromechanical as in larger guns such as tank guns, or they are 
electronic as used with non-manually controlled weapons such as 
antiaircraft weapons, particularly those controlled by radar. Each of the 
various conventional techniques of aiming a weapon has at least some of 
the above described drawbacks. 
One technique for overcoming the foregoing difficulties encountered in 
aiming a weapon is to project a laser beam or other appropriate light beam 
onto the target. When the target is illuminated by the laser or light 
beam, the trigger of the weapon is operated. If the laser or other light 
beam is properly zeroed in on the aiming point of the weapon, the 
projectile fired by the weapon will strike where the light is shining. An 
improved device of this type is described in copending application Ser. 
No. 769,533, now U.S. Pat. No. 4,152,754, the disclosure of which is 
hereby incorporated by reference. That device includes a mounting support 
which is fixedly attached to the weapon and the rest of the laser aiming 
device is attached to its mounting support. The aiming device includes 
zeroing means connected between the mounting support and the rest of the 
device and which enable the aiming point of the laser beam to be 
readjusted up and down or sideways after the aiming device is mounted on 
the weapon. 
In laser aiming devices, when the laser is operated, the laser beam is 
projected toward the target and is normally invisible. When it strikes the 
target, it forms a visible dot thereon. When the marksman has moved the 
weapon so that the visible dot is over the target, he operates the weapon. 
In the aiming device of the aforesaid application, the laser is activated 
by the marksman partially squeezing the trigger of the weapon. With the 
trigger partially squeezed, the weapon is aimed. When the weapon has been 
aimed, the marksman completes operating the trigger of the weapon. The 
projectile fired from the weapon should impact on the illuminated target 
if the laser beam has been properly zeroed in with the weapon. 
In any laser aiming device for use on a weapon, such as a rifle, the laser 
emits a monochromatic light beam, e.g. a red color light. At night, during 
heavily overcast conditions, indoors or in a darkened environment, the 
beam of light shining on the target is easily visible. However, outdoors 
during the day and in a bright environment, the ambient light effectively 
overwhelms the dot of laser light on the target making it difficult for 
the marksman to observe. 
SUMMARY OF THE INVENTION 
Accordingly, it is the object of this invention to provide an improved 
aiming device for a weapon which has the benefits described above and 
which avoids the drawbacks of the prior art described above, particularly 
the difficulty in observing the illuminated target under daylight or 
brightly lit conditions. 
This invention relates to a weapon aiming device particularly adapted for 
use under daylight or other brightly lit conditions and more particularly 
to a device comprising in combination a monochromatic light source, which 
is typically a laser, means connected to the light source for supplying 
power thereto, means for directing light emitted by the light source in an 
aiming direction, means to activate the light source, and means to view 
the area illuminated by the emitted light, which includes a light filter 
of the same wavelength as the laser beam (within tolerance limits), which 
permits passage of light of the same wavelength as the emitted light 
through the filter and blocks light of other wavelengths from passing 
through. 
The foregoing and other objects and features of the invention will become 
apparent to those skilled in the art from the following detailed 
description taken in conjunction with the accompanying drawings.

DESCRIPTION OF THE PREFERRED EMBODIMENT 
FIG. 1 is a perspective view of a rifle 1 fitted with an aiming device 
according to the present invention. The aiming device includes a laser 
emitting device 2, of the type described in aforesaid Application Ser. No. 
769,533 or of any other of the types known in this art. The laser emitting 
device 2 is fastened on top of the rifle 1 by appropriate attachment means 
4, such as that shown in the above noted Application, although the laser 
emitting device might be attached beneath the rifle also. The laser 
emitting device 2 is activated by an operator 6 which acts through a cable 
8 leading to the laser emitting device 2, as further detailed in the 
Application. 
A battery operated laser lamp or light source 12 is supported in the 
housing of the device 2. 
The front end plate 14 of the housing of the laser emitting device carries 
a laser beam outlet through which the laser light is directed at the 
target (not shown). 
The laser 12 can be a standard helium-neon laser operating at 5 milliwatt. 
An appropriate battery-transformer power source 22 such as that described 
in the Application, supplies power used by the laser. A laser beam is a 
luminous coherent monochromatic collimated light ray. In the 
above-mentioned laser, the emitted laser light beam is red in color, e.g. 
a wavelength of 633 milliradians. The illustrated red light emitting laser 
was selected because it can be made small in size and light in weight. As 
appropriate, any other wavelength laser may be used. 
It is usually difficult to see the laser light beam in the air unless the 
beam passes through smoke or floating particulates, or the like. However, 
when the laser beam strikes the target, it forms a visible monochromatic 
dot thereon. In a darkened environment, the dot is clearly visible to the 
marksman. But in a bright environment, e.g. bright sunlight, the sunlight 
includes all wavelengths of visible light and the laser light is mixed 
with all other colors of light. Furthermore, the ambient light so brightly 
illuminates the area surrounding the target and overwhelms the laser light 
dot thereby making the dot on the target difficult to observe. 
This difficulty is overcome in the present invention by the marksman 
observing the target through a suitable light filter which is precisely 
the same wavelength as and which therefore passes light of precisely the 
same wavelength as, the laser light, within minimal tolerance limits of 
.+-.30 manometers. For example, when the light has a wavelength of 633 
milliradians, the filter has the same wavelength, .+-.30 manometers. As 
the marksman looks at the illuminated target through the filter, the 
filter excludes all light except for light of its wavelength, and the 
filter thus darkens the markman's view of the area around the laser light 
dot on the target while the laser light dot on the target remains quite 
bright. The filter can be included as a part of the gunsight or viewing 
scope on the weapon or can be placed on the weapon where the sight or 
scope would otherwise be placed. It may be placed adjacent to the laser 
source on the weapon or be remote therefrom. A further alternative, 
although less preferred, is to provide the user of the weapon with a pair 
of eyeglasses having lenses which are filters of the desired wavelength. 
One embodiment for the mounting of the light filter is shown in FIG. 1. 
The light filter 30 of the first embodiment is supported in a light filter 
support housing 32 which is affixed atop the housing 2 for the laser 
source 12. The placement of the housing 32 positions the filter 30 on the 
rifle where a typical sight or scope might be placed. The housing 32 is 
comprised of a hollow cylindrical tube of metal with peripheral radially 
inwardly extending end flanges 34 at the end through which the operator 
looks and 36 at the end facing the target. The filter 30 is comprised of a 
planar glass lens of the precise wavelength of the laser light, within 
tolerance limits. The lens 30 is supported at its edge on a shaft 42 which 
is drivingly attached to an operating knob 44. As shown in FIG. 3, 
rotation of the knob 44 will rotate the lens 30 from the position shown in 
FIG. 2, which is its solid line position in FIG. 3 at which the operator 
of the weapon looks through the filter 30, to the horizontal orientation 
shown in FIG. 3, at which the operator sees the edge of the filter and the 
filter thereby appears to him to be a thick line running horizontally 
across the viewing field. 
The housing 32 is sealed at the operator's end by lens system 46 and at the 
target end by lens system 48 which are, for example, conventional lens 
systems found in a typical telescopic rifle sight or scope. As ambient 
light conditions dictate and as it becomes more or less difficult to see 
the dot of laser light on the target, the filter 30 is selectively 
swiveled around shaft 42 into and out of position to be used. 
In the second embodiment of the invention shown in FIG. 4, the rifle 1 is 
essentially the same rifle as the rifle shown in the embodiment of FIG. 1. 
However, there is no filter 30 on the rifle itself. Instead, the marksman 
50 wears a pair of removable spectacles 52, the lenses 54 of which are 
comprised of glass of the same wavelength as the laser light, within 
tolerance limits. In an obvious variation, the operator may wear a contact 
lens of the correct wavelength over the cornea of his eye. As ambient 
light conditions dictate, the marksman dons or removes the spectacles 52 
or the contact lens which, respectively, gives him a filtered view of the 
illuminated area of the target or an unencumbered view of that area of the 
target. The marksman looks at the target (not shown) through the sight 50 
or another conventional scope. 
Note that in all embodiments of the invention, even if the rifle is 
provided with a standard gunsight, the aiming of the weapon does not rely 
upon the gunsight but instead relies upon the beam of laser light 
illuminating an area of the target and the viewing of the illuminated area 
through a filter adapted to permit passage of light of an appropriate 
wavelength. 
Although the present invention has been described in conjunction with 
preferred embodiments thereof, many variations and modifications will now 
become apparent to those skilled in the art. It is preferred, therefore, 
that the present invention be limited not by the specific disclosure 
herein, but only by the appended claims.