WO2014024188A1

WO2014024188A1 - Firearm image combining sight

Info

Publication number: WO2014024188A1
Application number: PCT/IL2013/050667
Authority: WO
Inventors: Hanoch Kislev; Ran VARDI
Original assignee: Accutact Llc.
Priority date: 2012-08-06
Filing date: 2013-08-06
Publication date: 2014-02-13

Abstract

A system for combining a scene with images presented over a display is provided herein. The system includes: an optical device configured to capture a scene; an electronic display adapted to present images; a beam combiner adapted to receive the captured scene light and selectively combine it with at least a portion of the images presented by the electronic display; a selector configured to control a level of brightness of the electronic display so that a viewer is presented with: the captured scene, the images presented by the electronic display, or a combination thereof, wherein the beam combiner comprises one or more curved partially reflective surface sections operable for collimating at least a portion of the light emitted from at least a fraction of the images presented by the electronic display.

Description

FIREARM IMAGE COMBINING SIGHT

BACKGROUND

1. TECHNICAL FIELD The present invention relates to an imaging sight apparatus adapted to be placed on various firearms. Particularly, the present invention is directed to an apparatus adapted to combine images from various imaging modalities placed on the fire arm.

DISCUSSION OF THE RELATED ART

Generally, firearm users such as soldiers, security personnel and the like, relay on visual aides to obtain better an accurate views of targets at which those users aim when using a particular firearm. Such aids may include certain daytime and night time vision apparatuses, including scopes, infrared imagers, tight amplifying imagers, lasers and so forth. While such imaging modalities provide the firearm user a broad array of images, some which may be taken under varying lighting conditions, the firearm user may have to switch back and forth between the modalities, or the user may have to mount appropriate aiming devices until the user is ultimately in a position to effectively ascertain location and distance of a desired target relative to the point at which the user takes the aim towards the target. Such user operations, however, may take time and/or could be a source of distraction to the extent the firearm user may invest too much valuable time or, in worst cases, lose focus of the target, consequently, degrading the user's ability to obtain an optimal aim of the target.

BRIEF SUMMARY

Exemplary embodiments of the present technique disclose an apparatus adapted to be placed over a firearm, such as a fully or semi-automatic rifle, machinegun or any other suitable firearm or alternative weaponry. The apparatus includes an optical setup adapted for fusing/combining several images provided by different imaging modalities employed by the firearm. In exemplary embodiments, the optical set up is made up of a beam combiner, adapted for in-taking separate optical inputs to provide a single optical input to the user or shooter. In so doing, a single and simultaneous image is formed from at least a portion of each input provided by the various optical and other imaging modalities. In one embodiment, the apparatus may provide the user views gathered from a straight-on looking aim, as well as from a display device (e.g., LCD) of objects, targets and related data. The data presented to the user may include an aiming dot, crosshairs, GPS data, target distance data, and other data the user may employ when taking aim at a target. In accordance with the present technique, the apparatus is adapted to simultaneously merge (e.g., fuse) at least a portion of the aforementioned acquired images with, for example, image sensors including visible image sensors, nighttime imaging devices and the like, of objects or targets located in front of the user, as the user takes aim at those objects.

Advantageously, the apparatus may enable viewing at least a portion of the image displayed by the display device at high contrast on the background of the scenery viewed through the apparatus at full daylight conditions. Further, the apparatus may enable perception of at least a portion of the image displayed by the display device as positioned at large distance from the user.

Advantageously, by providing both views to the user, the disclosed optical apparatus will effectively provide the user with more detailed images of areas surrounding a desired target area, thereby enabling the user to better choose and aim at targets. Furthermore, as lighting conditions vary, the aforementioned apparatus may accentuate those images obtained by the imaging modality adapted to provide optimal images in the specific lighting conditions in which the firearm is being used. Thus, for example, during twilight, evening or in total darkness conditions, the beam combiner will effectively provide the user with nighttime images that could be qualitatively better than those provided by the straight-on looking device or other optical apparatuses used otherwise during daytime. Conversely, during the daytime, images provided by daytime imagining/optical modalities will naturally appear to the user as amplified relative to those provided by those modalities adapted to work better during attenuated light conditions or in darkness. Thus, in employing the beam combiner, the user can better focus on those images that may appear to be more detailed and/or better suited for taking an aim.

These, additional, and/or other aspects and or advantages of the embodiments of the present invention are set forth in the detailed description which follows; possibly inferable from the detailed description; and/or learnable by practice of the embodiments of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

For a better understanding of embodiments of the invention and to show how the same may be carried into effect, reference will now be made, purely by way of example, to the accompanying drawings in which like numerals designate corresponding elements or sections throughout.

In the accompanying drawings:

Figure 1A illustrate a side view of the combined image sight, in accordance with an exemplary embodiment of the present invention; Figure IB shows detailed view of the sight's beam combiner.

Figure 2A depicts a detailed ray tracing view of the optical apparatus and the User view of a display presented reticle, in accordance with an exemplary embodiment of the present invention;

Figure 2B depicts a schematic aspect of an embodiment of a beam combiner; Figures 3 A and 3B are side views of a firearm with a combined image sight, in accordance with an exemplary embodiment of the present invention;

Figure 4 is a view through the optical apparatus, as viewed by the user at daylight conditions, in accordance with an exemplary embodiment of the present invention; and

Figure 5 is another view through the optical apparatus, as viewed by the user at reduced illumination conditions accordance with an exemplary embodiment of the present invention.

DETAILED DESCRIPTION

Prior to setting forth the detailed description, it may be helpful to set forth definitions of certain terms that will be used hereinafter.

The term "beam combiner" as used herein refers to an optical component comprising at least three substantially flat external surfaces and at least one substantially flat diagonal internal surface. Said diagonal surface is coated with a suitable partially reflective coating and comprises at least one curved surface section. Said beam combiner is operable for combining the light emitted from objects in front of the first and second external surfaces such that a viewer viewing from the third external surface may perceive a combined image comprising at least a portion of each image perceived by viewing directly said objects in front of the first and second external surfaces.

The term "beam combining sight" as used herein refers to a sight comprising a beam combiner and at least one image display device coupled with the beam combiner.

The term "surface section" as used herein refers to a section of the diagonal beam combiner surface which is does not form a piecewise surface with the rest of said diagonal surface. The term "windage" as used herein refers to the the effect of the wind in deflecting a missile such as a bullet.

With specific reference now to the drawings in detail, it is stressed that the particulars shown are by way of example and for purposes of illustrative discussion of the preferred embodiments of the present technique only, and are presented in the cause of providing what is believed to be the most useful and readily understood description of the principles and conceptual aspects of the present technique. In this regard, no attempt is made to show structural details of the present technique in more detail than is necessary for a fundamental understanding of the present technique, the description taken with the drawings making apparent to those skilled in the art how the several forms of the invention may be embodied in practice.

Before explaining at least one embodiment of the present technique in detail, it is to be understood that the invention is not limited in its application to the details of construction and the arrangement of the components set forth in the following description or illustrated in the drawings. The present technique is applicable to other embodiments or of being practiced or carried out in various ways. Also, it is to be understood that the phraseology and terminology employed herein is for the purpose of description and should not be regarded as limiting.

In traditional art, a beam combining sight comprises a beam splitter comprising a piecewise substantially partially reflective surface is used to collimate the light emitted from the light source and passing it through a reticle. However, attempt to collimate a non-collimated extended reticle (e.g., reticle presented by a display) with such piecewise surface may encounter problems of reticle blur, distortion and reticle shift (caused by viewing a weakly collimated reticle light).

The inventors of the present invention unexpectedly discovered that the use of a beam combiner comprising one or more partially reflecting surface sections (e.g., surfaces array) instead of a single surface, enables viewing at least a portion of the displayed image with higher brightness, while viewed as positioned at large distance.

Accordingly, the first embodiment, the beam combiner sight system of the present invention includes: an imaging device adapted to receive light from a scene; a display adapted to present images; beam combiner adapted to receive the scene light from the scene and selectively combine it with at least a portion of the images presented by the display; and a selector adapted to be adjusted to permit the user to selectively operate the sight system as an occluded sight or a direct view sight or any combination thereof, wherein said beam combiner surface comprises at least one smaller curved surface section operable for collimating a fraction of the light of at least a portion of the presented images while partially reflecting that light towards the user eye.

In reference to Figure 1A and IB, the image combining sight system 12 according to the present invention, comprises optical apparatus 16 which includes a beam combiner 28 with a front aperture 14, back aperture/viewer 15, both of which are disposed at two ends of the beam combiner 28, a nighttime imaging modality 20, mounted on the apparatus 16. A display 31 is positioned adjacent to the beam combiner 28. It is understood that other imaging devices such as magnified imaging device may be used instead of nighttime imaging modality 20.

The display device (e.g., LCD) 31 may be disposed at one input faces of beam combiner 30. Hence, beam combiner 28 is adapted to intake and combine light rays entering the beam combiner 28 from the scene and the display device 31. For example, scene light represented by optical rays 32, enter aperture 14, enter the beam combiner 28 from the first direction, while the display 31 light represented by rays 34, enter the beam combiner 28, from a second direction, such that the rays 32 and 34 are substantially perpendicular to one another. Beam combiner 28 combines the rays 32 and 34, and, consequently, the images resulting from each of the rays 32 and 34 is viewed by the user eye 8 through aperture 15 as a single image represented by rays 35.

As shown in figure 1, the surface 30 within beam combiner 28 is a substantially flat coated surface and includes one or more discrete surface sections 30c. Each surface section 30C within surface 30 serves two functions: (a) it collimates the light emitted from at least a portion of the display's 31 pixels, such that the user views at least a portion of the image presented on the display as presented at a large distance; and (b) it collects larger fraction of light emitted from at least a portion of the display's 31 illuminated pixels, as an image forming light. Figure IB shows surface 30 as an array of surface sections 30C (only four are shown for the sake of simplicity).

In reference to Figure 1, the rays 32 may represent a daylight scene light viewed through aperture 14. The scene may comprise various regions in which desired target(s) are disposed and are visible to the user. The display device 31 may display information selected from: captured images (e.g., from imaging modality 20); pure data, such as global positioning satellite (GPS) data, compass data, target range data, images of crosshairs or reticule, and other graphical or alphanumerical data pertinent to user. Thus, the aforementioned data may also be provided as images, represented by rays 34, to the beam combiner 28 such that the data represented by those images can be superimposed on the image viewed by the user through the aperture 15. Fig. 2A illustrates detailed view of optical apparatus 16 with ray tracing of light passing from display 31 to the user eye 8. Light rays 34 emitted from two pixels 37 within display 31 is reflected from two surface sections 30c whose geometry is optimized for: a) Reflecting the rays 34 emitted from pixels 37 such that a significant portion of them are near-collimated; B) Reflecting a significant fraction of rays 34 so that the user perceives a focused image of pixels 37 while his eye 8 is focused to a large distance.

Fig. 2B shows a projection 200 of an image section (such as a grid) presented by display 31 as received in the user's eye. Bar 210 serves as a scale for estimating the magnification of the received image. It is noted that due to optical limitation the projected grid may exhibit varying intensity along the radial position in respect to the grid's center. It is noted that the shape of each discrete surface section 30C may be a parabolic, conic, generally aspheric or anamorphic shape operable to collimate the light from at least a portion of the displayed image and project it to the user eye 8 as a viewable image. The surface sections 30C may be arranged as array or in any other suitable arrangement. In certain aspects, the optical axes of the surface sections 30C are parallel. Accordingly the user can view desired portions of the presented image by laterally shifting his view axis parallel to aperture 15 axis. In other aspects, the center surface section axis is substantially parallel to the rifle barrel while the other surface sections 30C axes are converging towards the user. Accordingly, the user can view the displayed image by tilting his view line. Typically, the diagonal beam combiner surface 30 is coated by a certain coatings operable for reflecting roughly half of the light in the visible portion from the display to the user. In such case, the surface passes roughly half of the visible portion of the light from the scene to the viewer. In certain aspects the diagonal surface may partially or fully reflect certain spectral bands of light presented on the display or viewed through beam combiner 28. Imaging modality 20 may comprise imagers selected from nighttime imagers, cameras, charged coupled devices (CCDs), complementary metal on oxide devices (CMOS) and/or other silicon based devices, image intensifiers or other imaging modalities adapted to operate in low lighting conditions or at conditions in which the scene light as viewed from aperture 14 may not sufficient for aiming purposes. The device 20 may also include imagers sensitive to infra-red light and/or image intensifiers adapted to provide the user illuminated viewed of dark sceneries.

The imaging modality 20 may be operated using digital image acquisition techniques for producing digital images which may be coupled into beam combiner 28. As such, image combining sight 12 may include one or more digital processors for processing image data collected by the imaging modality 20, as well as rendering images to a display device 31 (e.g., LCD). The images provided to display 31 may be processed to include certain resolution and/or magnification in accordance with the user's choice and preference. It should be borne in mind that if images collected by the imaging modality 20 may be provided to the user as magnified, that is, provided differently from the straight-on aperture 14 (e.g., no magnification). One of the reasons, aperture 14 may be blocked for various reasons, including preventing the user from viewing two differently magnified views of the scene.

Example 1

In reference to Fig. 2A, A beam combiner 28 is coupled to display 31 presenting a reticle composed of 10 X 10 pixels sized 0.15 mm. The solid angle light emission from each pixel 37 within the reticle is 1 steradian. The maximum display luminance is 500 Cd/m2.

The beam combiner surface 30 comprises a rectangular 5 X 5 mm bi-conic curved surface 30C whose curvature is described by the parameters:

R_x = -44 k_x = 30 R_y - Sl Λ, = 10 Wherin R and k are the curvature radii and conic constants, while the subscripts x and y represents the x-horizontal and y-vertical directions of the scenery viewed by the user. The distance from the display 31 surface to the beam combiner surface 30 is 40 mm. A viewer eye located about 10 cm from aperture 15. Fig. 2B illustrates a display presented reticle (10 X 10 pixels) represented by a 1.5 X 1.5 mm grid, as seen by the viewer eye, while the scale bar's 210 size = 3 deg. It should be noted that about 35% of the reticle light reaching the above described surface section 30C is collimated as image forming light.

Referring now to the image/reticle projecting component, The optical system includes a display which may selectively display scene images captured by the camera and either processed by a processing block connected to the display driver, or directly fed into the display 31.

The display is operable for providing images to a user. The presented images may be continuously streamed to the display to provide dynamic imaging of the target scene. Alternatively, the images may be selectively fed to the display by the processing block. The images may include a reticle (e.g., one or more dots, crosshairs, diamonds, chevrons, marks of other appropriate shapes.

In some embodiment of the present invention, display 31 may extend beyond the image combining sight 12 so that the extended portion which is exposed, may serve as a graphical user interface, specifically if implemented as a touch screen so that touch screen buttons 31 A may enable the user to control various functionalities of the optical system 16. Advantageously, a single display 31 may serve both as a source for the image within the image combiner and as a user interface. It should be noted that the extended portion may not be necessarily at one of the sides of the optical device but can also be at the bottom of the optical device where it is more protected.

In one embodiment, the processing block may provide zoomed images on said display, using for example digital zoom features by a processing block. As a result, images of a target scene may be magnified as desired by the user or otherwise by an automatic control feature. Accordingly, the sight system of the present invention provides zoom capabilities along with a reticle.

In further aspects, the processing blocks drives the display to generate a distorted image such that the sight system projects an undistorted and smooth image to the user.

Referring now to the reticle, in certain aspects, the reticle is incorporated as part of the image presented by the display. In other aspects, the reticle is generated by an independent light source, collimated, possibly passes through a reticle mask, and projected to the viewer by reflection from reflective surfaces within the sight system.

In certain aspects, the reticle center location is determined by the processing block in consideration to parameters selected from group of parameter comprising: The required barrel tilt for compensating the ballistic path of the specific projectile about to be shot by the user; The location of the user eye relative to the sight system; and the range to the desired target as may be determined for example by a range finder.

In certain embodiments, the reticle may be perceived by the user as being superimposed over the images provided by the display. Sight system may be implemented such that the position of the reticle relative to the images provided by the display may be used to sight the rifle, thus providing a reflex sight. In other aspects, the sight system may also be used to provide a direct reflex sight by selectively disabling the camera or the display, for example in response to the user controls. Different types of display may be used. For example, in various embodiments the display may be implemented as liquid crystal display (LCD), a digital light processing (DLP) display, a fast scanning MEMs based display, an organic light emitting diode (OLED) display, or another type of display suitable for presenting the captured images. The display brightness may range between 200 - 500 Cd/m2, (typical for cellular applications) or above 1000 Cd/m2 (typical for outdoor display devices).

In certain embodiments, the surface or a section of the surface within the beam combiner may be operable for collimatmg the light from a group of pixels within the display operable for generating a reticle. Accordingly, when viewing the end of sight system, the user may see a reticle, knowing that a potential target is properly sighted when the reticle is viewed on the potential target.

The beam combiner sight of the present invention may be used to provide a direct reflex sight during daylight use of the sight system. Accordingly, proper utilization of the reticle requires high visibility of the reticle when superimposed on the scene. The main measure for a superimposed reticle visibility is its contrast in respect to the scene light. Without sticking to any specific theory, the reticle contrast level may be estimated using correlations developed for aviation warning light visibility, as demonstrated in the non limiting Example 2 below.

Example 2

A point light source whose luminance is at least Ip can be identified on a scene with luminance Lb located at a distance d from the user eye, according to Equation (1)

I_p = 2 * W* * d²L_{b (1)}

When viewed directly from the sight system, the optical power collected from an identified spot located at the scene and contribute to the spot image in the user eye is thus:

AI_pr

(2) When a reticle is superimposed on the scene, using a beam combiner with substantially flat surface, the typical fraction of reticle light power reaching the observer eye is given by Equation (3):

Wherein dv is the air equivalent distance between the display and the eye, He is the effective emission angle of a display pixel in steradian, A is the user's iris area and r is the reflection of the beam combiner surface. For example, the user eye having iris diameter of 3 mm, receives less than 0.1 % of the light emitted from the displayed reticle located 30 cm from a user eye. The optical power reaching the user eye as a reticle image power is calculated from Equation

(4):

ANrL_cb²

s = f₀NrL_cb² =

Ω ²

(4)

Here b is the pixel size, Lc is the display luminance in Cd/m2, N is the number of pixels allocated for presenting the red spot, Ω,ο is the pixel emission angle in steradians, dv is the display - eye distance and r stands also for the beam combiner transmission. When the light from the display reticle is collimated by a surface section of the beam combiner which is larger than the user eye iris, the optical power generating the reticle image in the user eye is given by Equation (5)

, _{Ar T} . ₂ ANrL b¹

s_c = f_cNrL_cb² = '

^ΩΑ (5)

The apparent contrast is defined as the ratio between the power of the threshold spot image and the image of the reticle is defined by Equation (6) below: r _ ± _ __ Nb² L„

6 ¹ _J

(6) For example, the contrast ratio of a reticle presented by the display is composed of 10 pixels sized 0.15 mm, with emission angle of 1 steradian and luminance of 500 Cd/m2 is collimated with a beam combiner surface section located 30 mm from the display. The reticle is superimposed on a far daylight scene with luminance of 7000 Cd/m2. Using these parameters and Equation (6), the reticle contrast ratio C = 9.

More important, from Equation (5) and Equation (6) one can derive the ratio between the display luminance as observed by the user with and without collimation at the beam

(L I L Ϋ

combiner, which is ^{v c} . For example, for a display - beam combiner surface distance of 30 mm and eye - display distance of 300 mm, the contrast enhancement is -100. Accordingly, the sight system of the present invention provides a display presented reticle superimposed on a daylight viewed scene at a very high contrast.

Further, one or more surface sections may reflect additional information such as text, graphics or images presented by the display and in turn superimpose it on a daylight scene viewed through the image combining sight, at a very high contrast. Focusing now on the imaging device, the sight system includes an imaging device adapted to capture images from the scene using a silicon based imager having a typical silicon spectral response. In other aspects, the imager's spectral response curve may be modified (e.g., enhanced only in the near IR spectral range). Accordingly, the sight system of the present invention may be operable for viewing the scene along with a superimposed captured image of the scene (with the same magnification) providing enhanced target detection capability to the user.

Focusing now on the selector, the sight system of the present invention comprises a selector, adapted to be adjusted for a plurality of positions that vary between two positions, a first and a second position: The first position operable to substantially permit the scene light to be viewed by the user while only the presented reticle remains viewable by the user to permit the user to operate the sight system in direct mode. The second position is with the selector being operable to substantially prevent the scene light from being viewed by the user while the scene image and the reticle are viewed by the user to permit the user to operate the sight in an occluded mode. The selector may be implemented as control electronics embedded within display 31 and configured to control a level of brightness of the display. Alternatively, the selector may be a layer of controllable filters placed on display 31 which is configured to control the amount of light coming from display 31 towards beam combiner 28.

Those skilled in the art will appreciate that the scene brightness represented by rays 32 may have different brightness from the display presented image represented by rays 34, such that the user may view mainly one image through aperture 15. For example, during daytime lighting conditions, combined images of a target formed by the beam combiner 28 may appear to the user to be mostly dominated by the scene light, passing through aperture 14. Conversely, as lighting conditions become less bright (more dimmed), the images represented by rays 34 may dominate the scene light represented by rays 32, so as to overwhelm those images viewed through the aperture 14.

It should be appreciated that beam combiner 28 may combine the view of scene light from aperture 14 and a portion of the image captured by nighttime device 20 and presented by display 31, in such way that the scene features viewed through aperture 14 may not be noticeable or may be otherwise absent from images captured by the imaging device 20. In so doing, the beam combiner 28 provides the user a comprehensive and detailed view of surrounding regions and desired targets at which the user wishes to take aim.

The sight system 12 may comprise an auxiliary reticle superimposed on scene view and not presented by display 31. The auxiliary reticle may be a transparency, a hologram, or a structured light such as a structured LED array. The reticle may be illuminated by an electrical light source, a LED, a laser diode or a radioactive light source.

Rifle mounted sight system

The beam combiner sight system of the present invention may be selectively used in a variety of different ways and mounted on a system including: a firearm, a projectile delivery system, a surveillance system or an images capturing system. The sight system may be positioned on with its optical axis substantially parallel to the barrel of a firearm. Such an implementation may permit the user to effectively sight the firearm without blocking the user peripheral vision and without compromising situational awareness. Figure 3 illustrates a specific embodiment of the sight system mounted on a firearm. Fig. 3 A is a side view of a firearm 10, in accordance with an embodiment of the present invention. The firearm 10 may be a rifle, an automatic or semi automatic or other delivery system used by soldiers, government or other security personnel, hunters, and/or other individuals. The firearm 10 includes aiming image combining sight 12 comprising optical apparatus 16 and mounted on mount 18. The firearm 10 further includes a nighttime imaging modality 20, mounted on image combining sight 12, and adapted to operate in nighttime or darkness for collecting images in a field of view in which firearm is used.

The firearm 10 may be a rifle, an automatic or semi automatic or other weapon used by soldiers, government or other security personnel, hunters, and/or other individuals. The firearm 10 includes aiming image combining sight 12 including a front aperture 14, back aperture/viewer 15, both of which are disposed at two ends and adjacent to optical apparatus 16 mounted on mount 18. The firearm 10 further includes a nighttime imaging modality 20, mounted on the apparatus 16, and adapted to operate in nighttime or darkness for collecting images in a field of view in which firearm is used.

Further, the optical apparatus 16 is adapted to provide the user of the firearm 10 a simultaneous view of all images collected by the aperture 14 and imaging sensor device 20. The image sensor 20 may include one or more cameras, such as those adapted to work at low lighting conditions. The device 20 may also include infra red imagers and/or image intensifiers adapted to provide the user illuminated viewed of dark sceneries. The aforementioned device may utilize charged coupled devices (CCDs), complementary metal on oxide devices (CMOS) and/or other silicon based devices together with digital image acquisition techniques for producing digital images which can be further be made available to the user through aperture 15. As such, image combining sight 12 may include one or more digital processors for processing image data collected by the images sensor 20, as well as rendering images to a display device (e.g., LCD), included also within the apparatus 16. The images provided to the LCD may be processed to include certain resolution and/or magnification in accordance with the user's choice and preference. It should be borne in mind that if images collected by the sensor 20 are provided to the user as magnified, that is, provided differently from the straight-on aperture 14 (e.g., no magnification), then aperture 14 may be blocked so as not to provide the user with two differently magnified views of the target at which the user takes aim. Image combining sight 12 includes a beam combiner adapted to obtain to views from two directions and combine those in a single view to the user. Accordingly, the apparatus 16 may include additional optical and/or electro-optical elements, such as apertures, reflective coatings, photo-detectors and other optical aids adapted to modify and configure the images obtained through the aperture 14 and the device 20. As mentioned, the apparatus 16 can also combine images provided by electronic and digital display devices, such as liquid display devices (LCDs) and the like.

Thus, when a user of the firearm 10 takes aim at a target disposed in front of the firearm 10, i.e., in front of barrel 22, the user may look through the viewer 15 towards the desired target to obtain a combined image that includes images provided by the aperture 14, as well as those images collected by the images sensor 20 and provide to the display device 31 of within the apparatus 16.

In some embodiment of the present invention, as shown in figure 3B, display 31 may extend beyond the image combining sight 12 so that the extended portion which is exposed, may serve as a graphical user interface, specifically if implemented as a touch screen so that touch screen buttons 31 A may enable the user to control various functionalities of the optical system. Advantageously, a single display 31 may serve both as a source for the image within the image combiner and as a user interface.

Fig. 3B shows detailed magnified view of the beam combining sight 12 mounted on a rifle 10. Here the exposed display device area may be selected from a group comprising: A graphical user interface; a touch screen, for example with touch screen buttons 31 A which may enable the user to control various functionalities of the optical system; and an information exchange terminal. Advantageously, a single display 31 may serve both as a source for the image combined by the optical apparatus 16 and as a user interface. In certain applications, it may be advantageous to place display 31 below the beam combiner 28 rather than adjacent to its side facet.

In some other embodiments, the optical system further includes a shutter configured to block light from the scene altogether so that the viewer is only provided with images from the display. Figure 4 is a front view of an image generated by an optical apparatus 16, in accordance with an exemplary embodiment of the present invention. The display presents only the reticle which is superimposed on the scene. While, the image illustrated by Figure 4 may be taken in good lighting conditions the image may, nevertheless, contain objects which are less visible or are otherwise obscure from view. For example, images of persons 46 may not be noticeable to the user because of various factors. For instance, the persons 46 may be camouflaged by certain clothing or other obscuring aids adapted to hide the persons 46. By further example, the persons 46 may be located in a shadowed area or in the vicinity of other structures that could render the images of the persons 46 unclear to the user of the sight 12. By contrast, Figure 5 illustrates an image similar to that shown in Figure 4, however, taken during poor lighting conditions such as those existing during nighttime. In such lighting conditions, the optical apparatus, combines the scene light passing through aperture 14 and nighttime vision device 20 (e.g., a thermal camera) captured image presented by display 31, and a reticle. The user may view persons 46 completely visible while the viewed contrast of building 40, tree 42 and vehicle 44 may be reduced, as depicted by dashed lines outlining the aforementioned elements. Thus, the apparatus 16 provide the user with combined view with enhanced details which help the user to aim on his selected target.

Claims

1. A system comprising:

an optical device configured to capture a scene;

an electronic display adapted to present images;

a beam combiner adapted to receive the captured scene light and selectively combine it with at least a portion of the images presented by the electronic display;

a selector configured to control a level of brightness of the electronic display so that a viewer is presented with: the captured scene, the images presented by the electronic display, or a combination thereof,

wherein the beam combiner comprises one or more curved partially reflective surface sections operable for collimating at least a portion of the light emitted from at least a fraction of the images presented by the electronic display.

2. The system of claim 1 , wherein the electronic display is a liquid crystal display.

3. The system of claim 1, wherein said electronic display is a touch screen that further extends beyond a housing that includes the beam combiner aperture so as to present in the extended portion, data to the user and to further serve as a user interface in the extended portion.

4. The system of claim 1 , wherein said portion of the presented image comprises a reticle.

5. The system of claim 1, further comprising a shutter configured to block light from the scene.

6. The system of claim 4, wherein said reticle is a dot.

7. The system of claim 1, further comprising a light source, wherein a reticle not being included in the scene is presented to the user.

8. A method comprising:

receiving light from a scene through one of a beam combiner input facets; operating an electronic display to present a reticle such that said reticle is superimposed on the scene light for viewing by the user wherein the presented reticle light is collimated by the beam combiner; and

controlling the intensity of the light emitted by the electronic display so that a viewer is presented with: the scene, the images presented by the electronic display, or any combination thereof.

9. The method of claim 8, further comprising aligning the sight system relative to a firearm to aim the firearm and to permit the user to operate the sight system as a direct view sight or as an occluded sight or any combination thereof without further changing the alignment of the sight system and without adjusting the orientation of the beam combiner relative to the sight system.

10. The method of claim 8, wherein the reticle position in the presented image is adjusted to compensate for parameters selected from a group comprising at least one of: range to target, type of firearm ammunition, windage, and user eye position.

11. The method of claim 8, further comprising monitoring at least a portion of the scene light and responsively providing a control signal to the display driver, thereby providing the desired contrast ratio between the scene light and superimposed displayed image, as viewed by the user.

12. The method of claim 8, wherein the beam combiner comprises at least two transparent polymer components fabricated by injection process, and their mating surface is coated with an appropriate beam combiner coating.

13. The method of claim 12, wherein said transparent components are injected from polymers materials selected from a group comprising: Polycarbonate, PMMA and polyester.