US20090019759A1

US20090019759A1 - Telescopic sight optical glare reduction device

Info

Publication number: US20090019759A1
Application number: US11/805,537
Authority: US
Inventors: Larry Alan Martin; David Emerick
Original assignee: EM MAR MANUFACTURING LLC
Current assignee: EM MAR MANUFACTURING LLC
Priority date: 2007-05-22
Filing date: 2007-05-22
Publication date: 2009-01-22

Abstract

A telescopic rifle sight shade has a flat body made of flexible and durable material. The device has a strap dimensioned and configured to wrap around a rifle sight and an overhanging shade portion which may extend out from the sight. Fasteners on the device allow it to be fastened to itself. The material of the device may be neoprene, butyl, other polymers, other rubbers, other elastomers, leather, fabrics, composites and combinations thereof.

Description

COPYRIGHT NOTICE

A portion of the disclosure of this patent document contains material which is subject to copyright protection. The copyright owner has no objection to the facsimile reproduction by anyone of the patent document or the patent disclosure, as it appears in the Patent and Trademark Office patent file or records, but otherwise reserves all copyright rights whatsoever. 37 CFR 1.71(d).

CROSS-REFERENCE TO RELATED APPLICATIONS

N/A

INVENTORS

David Emerick
Larry Martin

FIELD OF THE INVENTION

This invention relates generally to telescopic sight devices, and specifically to shades for telescopic gun sights.

STATEMENT REGARDING FEDERALLY FUNDED RESEARCH

This invention was not made under contract with an agency of the US Government, nor by any agency of the US Government.

BACKGROUND OF THE INVENTION

Simple optical systems such as hunting rifle telescopic sights have a simple functional problem inherent in the design of the sight.
Most common optical devices have what is called a “field of view” and a “magnifying power”. The field of view is the total area seen by the eye when viewing through the optical device. Magnifying power is a rating of how much larger or smaller an object appears as compared to viewing it without the device. Various additional factors determine how clearly an object is seen, how much of it is seen, and how large it appears. The distance from the viewer to the object, the size of the object, intervening obstructions and the like have effects also, however, the factors related to the design of the telescopic sight itself are magnifying power and field of view, which depend upon the optics of the device and the related structures such as the body. Other common optical systems such as binoculars, telescopes and the like may have similar though slightly different relationships, as they have similar but different structures and optics.
FIG. 1 illustrates the field of view of a telescopic sight. The field of view is conical in shape (or frusto-conical) and only objects within the field of view will be seen by a user of the sight. As shown in FIG. 1, an animal further from the sight might be smaller but entirely in view, while an animal closer to the gunsight might be larger, but only partially in view.
FIG. 2 shows a second cone, the “cone of incidence”, which is typically larger than the field of view and thus typically encompasses the field of view. The optics of this cone are important. Light rays within this cone and the field of view will strike the lens of the device, or are incident to the lens. The light rays that are within the cone of incidence will reach the optics of the eyepiece. Even light rays within the cone of incidence but outside of the field of view (“stray light”) can substantially effect the optics, for example, causing geometric light patterns or spots or faint images of eyeballs in the field of view (caused by the stray light projecting into view an image of the user's own eyeball or the optics inside of the lens). This light can also cause distortion, fuzzy images, blur or may wash out the images. Such problems are not only due to the sun (although the sun is the major culprit), under low light conditions such as dusk, dawn and night, even bright lights can cause these problems.
Note that similar effects occur at the opposite end of the sight, that is, it is possible for light rays to pass beside the user's head, strike the lens, and either be reflected towards the animal or occlude the optics, or what is worse, be reflected by the optics towards the user. Under normal conditions, the user's face is so close to the sight that their head will block such rays, but a shield might under some circumstances be useful at this end also.
If the cone of incidence were the same shape as the field of view then such stray light problems would be practically eliminated. However, this is not always practical. Most telescopic sights have the objective lens mounted at or very close to the end of the device housing/body. This mounting location creates a very large cone of incidence. Extending the body of the device, or moving the lens back into the body, would reduce the cone of incidence by shading the lens, but at the fairly substantial penalty of greatly increasing the length and size of the telescopic sight.
Various structures are known to attempt to shield or shade telescopic lenses. One general category of device is tubular in shape, usually of matte black finish in metal or plastic or rubber. These tubular devices range in length from around 2 inches to around 4 inches, come in diameters ranging from roughly 20 mm to 80 mm, and either slip over the end of the sight body or screw onto the end of the sight body. In general, it is believed that these devices will reduce the incidence of stray light.
However, these devices have their own problems. The devices are typically quite stiff or rigid, and add length to the end of the telescopic sight. A bump on the device thus becomes a bump onto the telescopic sight. The telescopic sight may be damaged, or thrown out of adjustment. “Sighting in” a rifle scope can be a time consuming process, time which is usually not desirable during hunting trips. If the scope is not sighted in, it may become virtually useless.
In addition, these devices are sold in set diameters from roughly 20 mm to roughly 80 mm. This means that a device for one telescopic sight may not work on another telescopic sight. In addition, many are made to be threaded onto the rifle scope, so a bump can damage the threads as well, and the odds of interchangeability between sights go down even more with threading.
A search of the collection of the United States Patent and Trademark Office reveals class 42, subclass 129, “Firearms/IMPLEMENTS/Sight devices/Telescopic type/Lens cover, scope hood, or shade.” Within this class, various types of reference devices may be seen which all are different from the invention of the present application.
U.S. Pat. No. 6,811,268 issued Nov. 2, 2004, to Watson, is typical of the tubular design, and has no flexible straps to hold it on.
U.S. Pat. No. 5,850,706 issued Dec. 22, 1998 to Evans, teaches another tubular design but for a scope protector which at least has the benefit of being flexible, but which lacks straps and thus interchangability with numerous sights. It is also of dubious value as a shade, since it is not a shade but rather a cover, as is U.S. Pat. No. 5,661,920 to the same inventor on Sep. 2, 1997.
U.S. Pat. No. 5,642,585 issued Jul. 1, 1997, to Watley, teaches a flexible material with straps to hold it around the scope body, unfortunately, what it does not teach is any sun shade portion. In fact, as this device teaches that it should be wrapped around the scope in a medial position (by having straps the entire width of the device and by showing this position in the diagrams) it cannot even be combined with any other device which might teach leaving one side hanging over the end of the telescopic sight: combinations of prior art may not alter the fundamental operation of a device.
U.S. Pat. No. 5,506,727 issued Apr. 9, 1996 to Douglas et al teaches yet another tubular device designed without straps of any type.
It would be advantageous to provide a soft, flexible device which would fit a range of scopes.
It would be advantageous to provide a device allowing inexpensive manufacture and easy operation.
It would be advantageous to provide a rifle scope shade with features allowing easy attachment, adjustment and removal.

SUMMARY OF THE INVENTION

General Summary
The present invention teaches a rifle scope shade made of a soft flexible materials such as neoprene, butyl, other polymers, other rubber compounds, other elastomer compounds, leather, fabric or the like.
The device has fasteners and a strap portion allowing it to be fastened to a rifle telescopic sight by a user using thumb and finger or knuckle. The device has a shade portion projecting out from the end of the rifle sight, this shade portion may be semi-circular, semi-cylindrical, triangular or a variety of other shapes.
Fasteners may be hook and loop fabric, or may be hooks, buttons, snaps or the like in alternative embodiments.
In use, the rifle user wraps the device around the end of the scope, with the strap portion extending all the way around the barrel of the scope to be fastened with the fasteners. A thumb tab portion is dimensioned and configured for easy use by the user's thumb, and allows the device to be pulled on or adjusted once on, against the substantial (and desirable) friction between the polymer body of the device and the scope body.
Summary in Reference to Claims
It is therefore another aspect, advantage, objective and embodiment of the invention, in addition to those discussed previously, to provide a telescopic rifle sight shade comprising:

- a generally flat body of a flexible material, the body having a shade portion and a strap portion;
- the shade portion being approximately semicircular and projecting from the body in a first location;
- the strap portion projecting from the body in a second location;
- the strap portion dimensioned and configured to pass about such telescopic rifle sight; and
- at least one fastener disposed upon the body;

It is therefore another aspect, advantage, objective and embodiment of the invention, in addition to those discussed previously, to provide a telescopic rifle sight shade, further comprising:
a thumb tab projecting from the body in a third location.
It is therefore another aspect, advantage, objective and embodiment of the invention, in addition to those discussed previously, to provide a telescopic rifle sight shade, wherein the thumb tab further comprises:
a height and width dimensioned and configured to allow a convenient thumb grip.
It is therefore another aspect, advantage, objective and embodiment of the invention, in addition to those discussed previously, to provide a telescopic rifle sight shade, wherein the body is made from a material comprising one member selected from the group consisting of:
neoprene, butyl, other polymers, other rubbers, other elastomers, leather, fabrics, composites and combinations thereof.
It is therefore another aspect, advantage, objective and embodiment of the invention, in addition to those discussed previously, to provide a telescopic rifle sight shade, wherein the fastener further comprises at least one member selected from the group consisting of:
hook and loop fabric, a button, a snap, tacky material, a hook, and combinations thereof.
It is therefore another aspect, advantage, objective and embodiment of the invention, in addition to those discussed previously, to provide a telescopic rifle sight shade, wherein the shade portion further has a radius of at least 0.5 inch.
It is therefore another aspect, advantage, objective and embodiment of the invention to provide a telescopic rifle sight, wherein the strap portion has a length of at least 2.5 inches.
It is therefore another aspect, advantage, objective and embodiment of the invention to provide a telescopic rifle sight, wherein the shade portion shape is of one member of the group consisting of: generally semicircular, truncated semi-circular, rectalinear, elliptical, oval, irregular, triangular and combinations thereof.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates the conical field of view of a telescopic rifle sight.

FIG. 2 shows a second cone, the “cone of incidence” of a telescopic rifle sight.

FIG. 3 is a perspective view of a PRIOR ART rifle sight sun shade.

FIG. 4 is a planform view of a first embodiment of the invention.

FIG. 5 is a side view of a second embodiment of the invention.

FIG. 6 a is a side view depicting one end of a telescopic rifle sight.

FIG. 6 b is a side view showing one end of a rifle sight with the invention thereon.

FIG. 7 is a planform view of another embodiment of the invention.

INDEX OF REFERENCE NUMERALS

Tubular body 302
First open end 304
Threading 306
Overhanging shade portion 402
Strap 404
Pull/thumb tab 406
Overall length 408
Strap width 410
Shade radius 412
First width 414
Tab width 416
First radius 418
Second radius 420
Body 502
Hook fabric 504
Loop fabric 506
Telescopic sight body 602
Telescopic sight end 604
Shade 606
Strap 608
Pull tab 610
First radius 718
Second radius 720

DETAILED DESCRIPTION

FIG. 1 illustrates the conical field of view of a telescopic rifle sight.
FIG. 2 shows a second cone, the “cone of incidence” of a telescopic rifle sight. As noted earlier, the optics of this cone are important.
Light rays within this cone may strike the lens of the device, or are incident to the lens. The light rays that are within the cone of incidence will impact the optics of the device, and even light rays within the cone of incidence but outside of the field of view (“stray light”) can substantially effect the optics, for example, causing geometric light patterns or spots or faint images of eyeballs or shapes in the field of view. This light can also cause distortion, fuzzy images, blur or may wash out the images. Such problems are not only due to the sun (although the sun is the major culprit), under low light conditions such as dusk, dawn and night, even bright lights can cause these problems. Naturally, these problems adversely affect accuracy of rifle users and thus, attempts to defeat incident light have been made. Added shielding is shown in use, functionally reducing the size of the cone of incidence.
FIG. 3 is a perspective view of a PRIOR ART rifle sight sun shade.
Tubular body 302 is typically made of metal or another rigid material such as high impact plastic or the like. First open end 304 has threading 306 which allows it to be screwed onto/into the end of a telescopic sight. The threading may be internal or external, depending upon the telescopic sight: normally external threading on the shade to match internal threading on the end of the scope body. The internal threading is a preexisting feature of many or most scopes.
In use, such devices function as an extension of the telescopic sight, usually sans an optical element. The size of the cone of incidence is markedly reduced, but the extension has problems such as being time consuming to attach and detach, causing the rifle sight to be knocked out of true if the shade is accidentally bumped and so on.
FIG. 4 is a planform view of a first embodiment of the invention. The invention is made of a soft flexible material for the body, which is generally planar in the unrolled position. Overhanging shade portion 402 will serve as a shade portion when the device is in use, while the strap 404 will secure the device to the end of a rifle telescopic sight. Pull tab/thumb tab 406 is a convenience for attaching the device and adjusting it, as will be seen later in reference to FIG. 6 b.
The material of the invention may any of the following, with various advantages and disadvantages. In the presently preferred embodiment and best mode presently contemplated for carrying out the invention, the material neoprene is used however, in other embodiments other materials may be used instead, for example, other polymers may be used, including foams, also leather may be used, woven materials, other elastomers, other polymers, butyl, composites, and combinations thereof.
Various dimensions may be seen. The overall length 408 and shade radius 412 are largely determined by the size range of the telescopic sights for which the device is designed.
Strap width 410, first width 414 and tab width 416 on the other hand are generally functions of convenience and practicality: testing has revealed that a strap which is too narrow is not as stable as a broader strap in terms of holding the device in place, while tab width 416 needs to be sized to the human thumb and knuckle to allow easy gripping.
First radius 418 and second radius 420 show two exemplary radii of angles of the device, and may range from zero radius (sharp angles) on up. All radii may be identical in embodiments, or there may be two or more different radii.
Table One shows the dimensions of one size which has been tested. This size is appropriate for rifle sights ranging from 32 millimeters in size to 42 millimeters in size.

TABLE ONE

Overall length	7.00	inches
Strap width	0.75	inches
Shade radius	1.5	inches
First width	1.25	inches
Tab width	1	inch
First radius	0.12	inch
Second radius	0.12	inch

End Table One

However, it must be understood that the embodiment of Table One is exemplary only. In fact, the invention may be made in a wide range of sizes. For example, Table Two provides dimensions and configuration information for a larger embodiment, an embodiment more suited to a telescopic rifle sight of 46 millimeters to 56 millimeters in size.

TABLE TWO

Overall length	8.6	inches
Strap width	0.75	inches
Shade radius	1.875	inches
First width	1.25	inches
Tab width	1.00	inch
First radius	0.25	inch
Second radius	0.5	inch

End Table Two

FIG. 5 is a side view of a second embodiment of the invention. Body 502 may be seen to have a fairly thin and flat configuration. Fasteners 504, 506 may be any of a variety of items such as snaps, hooks, tacky materials, buttons, ties, or the like, but at the present time by far the preferred embodiment is hook and loop fabric. For example fastener 504 may be hook fabric while fastener 506 may be loop fabric.
FIG. 6 a is a side view showing one end of a rifle sight without the invention thereon, while FIG. 6 b is the side view showing the invention in use. Telescopic sight body 602 has telescopic sight end 604. Shade 606 extends past the sight end 604 to reduce the angle of incidence. Strap 608 may be seen to be wrapped around the barrel of the telescopic sight and fastened to the body of the device to hold the device snugly in place. Different strap, shade and tab configurations, sizes and numbers may allow the device to be used with similar optical systems such as binoculars, telescopes including spotting scopes, surveying instruments, and the like. It will be appreciated that pull tab 610 allows the user to adjust the device while it is installed, albeit with difficulty due to the friction of the device on the body. The pull tab 610 also provides a convenient hand grip to the device while the device is being installed: the tab 610 is not part of the strap assembly so it stays in one place during the install process, or if the user elects to connect the fasteners of the device and then pull it on, the tab may be used to pull it without using the strap.
FIG. 7 is a planform view of another embodiment of the invention. In this embodiment the thumb tab is in a slightly different location, showing that the thumb tab may be in any of a variety of locations, or omitted altogether. Different versions leave the thumb tab in different locations when installed. For example, the thumb tab 610 of FIG. 6 corresponds to the thumb tab of FIG. 7. It may be seen that the radii may be the same or different for different curves of the device.
Additional straps may be used as well, additional thumb tabs.
The disclosure is provided to allow practice of the invention by those skilled in the art without undue experimentation, including the best mode presently contemplated and the presently preferred embodiment. Nothing in this disclosure is to be taken to limit the scope of the invention, which is susceptible to numerous alterations, equivalents and substitutions without departing from the scope and spirit of the invention. The scope of the invention is to be understood from the appended claims.

Claims

1. A telescopic rifle sight shade comprising:

a generally flat body of a flexible material, the body having a shade portion and a strap portion;

the shade portion projecting from the body in a first location;

the strap portion projecting from the body in a second location;

the strap portion dimensioned and configured to pass about such telescopic rifle sight; and

at least one fastener disposed upon the body;

2. The telescopic rifle sight of claim 1, further comprising:

a thumb tab projecting from the body in a third location.

3. The telescopic rifle sight of claim 2, wherein the thumb tab further comprises:

a height and width dimensioned and configured to allow a convenient thumb grip.

4. The telescopic rifle sight of claim 1, wherein the body is made from a material comprising one member selected from the group consisting of:

neoprene, butyl, other polymers, other rubbers, other elastomers, leather, fabrics, composites and combinations thereof.

5. The telescopic rifle sight of claim 1, wherein the fastener further comprises at least one member selected from the group consisting of:

hook and loop fabric, a button, a snap, tacky material, a hook, a tie, and combinations thereof.

6. The telescopic rifle sight of claim 1, wherein the shade portion further has a radius of at least 0.5 inch.

7. The telescopic rifle sight of claim 1, wherein the strap portion has a length of at least 2.5 inches.

8. The telescopic rifle sight of claim 1, wherein the shade portion shape is of one member of the group consisting of: generally semicircular, truncated semi-circular, rectalinear, elliptical, oval, irregular, triangular and combinations thereof.