A system and method for adjusting the focal length of an image displayed to a simulator user.

Abstract

This invention provides a system and method for adjusting the focal length of an image displayed to the user from a specified viewpoint in a simulator. [Solution] An image reflected by a mirror at a specified viewpoint can be generated for display on a screen. A simulated distance from the specified viewpoint to the object in the image can be determined. Based on the simulated distance, the focal length of the image can be determined. Based on the simulated distance, the size of the simulated object can be determined. An adjuster can adjust the size of the object in the image based on the simulated size.

Description

Technical Field

[0001] This application claims priority under 35 U.S.C. § 119(e) to U.S. Provisional Patent Application No. 63 / 279,566, filed Nov. 15, 2021, the entire disclosure of which is hereby incorporated by reference.

[0002] The present invention generally relates to adjusting the focal length of an image presented to a user from a specified perspective of a simulator. More specifically, the present invention provides a system and method for adjusting the distance between a screen and a mirror of a simulator based on a simulated distance between a specified perspective and an object of an image displayed on the screen and reflected by the mirror. An adjuster is provided for adjusting the distance between the screen and the mirror.

Background Art

[0003] Advanced simulators (such as flight simulators) that train users to operate a vehicle typically include a main display that provides an image of the environment around the vehicle to the user. Referring to FIG. 1, a real-world image 12 of the main display 4 is realized by collimating light (e.g., an image) to the user 30, whereby the image is rendered at an infinite focus. For example, the focal length of the image may exceed about 30 feet. The projector 6 projects the image 12 onto the screen 8, and the image is presented to the user 30 (such as a pilot) as a reflection of the mirror array 10. As shown in FIG. 1, the image 12 of the main display 4 is presented to the user as collimated light rays 14, as indicated by the first arrow 34, and is viewed at a long-distance focus. The collimated light rays 14 are substantially parallel to each other.

[0004] Some vehicles, including helicopters and other aircraft, have windows called "chin windows" that allow the pilot to look downwards from the aircraft, as shown by the second arrow 36 in Figure 1. Chin windows may be located near the floor of the aircraft's cabin or cockpit. On some aircraft, chin windows are located in front of the aircraft's rudder pedals. Pilots can use chin windows to check for reference points or objects (such as the ground) during takeoff, landing, and while the aircraft is hovering.

[0005] Some conventional simulators 2 include a chin display 20 that reproduces objects 16B visible outside the cockpit through a chin window 18. Known simulators typically use either a real-image display system or a wide-angle collimated (WAC) display system to display images seen through the chin window.

[0006] The real-image display system 20 uses a monitor or side projection screen 22 positioned in front of the simulator's lower window 18. The simulator pilot or user 30 views the image 24 of the real-image display system through the lower window 18. The viewing distance of the simulated image 24 created by the real-image display system is approximately 6 to 8 feet. The viewing distance is equal to the physical distance between the designated viewpoint 32 of the simulator 2 and the monitor or screen 22 of the real-image display system 20. As a person skilled in the art will understand, the designated viewpoint 32 represents the preferred or optimal position of the user's eyes when inside the simulator. The designated viewpoint is used when designing the components of the simulator to provide the optimal view image created by the simulator for the user to see.

[0007] The real-image display system 20 provides realistic depth cues when the simulator provides a simulation of flying at a simulated height 28 or less, approximately 10 feet higher than the simulated ground 26. The real-image display system also provides bright, clear images with a relatively wide field of view (FOV). However, known real-image display systems 20 have several drawbacks, including incompatibility with night vision goggles (NVGs) when the NVGs are focused to be compatible with the near-infinity focus of the main display 4. As understood, this prevents the simulator from being used to provide training for specific activities and some simulated conditions (such as night flight operations), negatively limiting the training possible with conventional simulators 2.

[0008] Furthermore, as schematically shown in Figure 1, the object 16B in the image 24 generated by the real-image display system 20 for viewing through the lower window 18 is misaligned with the object 16A in the collimated image 12 of the main display 4 as the user's head moves. This problem is schematically shown in Figure 1, where the top of the tree 16A displayed in the image of the main display 4 is horizontally misaligned with the bottom of the same tree 16B displayed in the image 24 generated by the real-image display system 20.

[0009] Furthermore, because the real-image display system has a fixed focus and the main display is at infinity focus, the user's eyes need to adapt to different focal lengths when looking out from the lower window (indicated by the second arrow 36) and then from the main window (indicated by the first arrow 34). This change in focus negatively impacts the realism of the simulator, causing discomfort to the user and leading to eye strain. Known real-image display systems also provide unrealistic depth cues when the simulated aircraft is at a simulated height approximately 10 feet higher than the simulated ground 26.

[0010] The WAC display system, used as a chin display, offers several advantages compared to real-image display systems. For example, the image provided by the WAC display system has an infinite focus. When viewed through the simulator's chin window, the image provided by the WAC display system remains consistent with the image 12 on the main display 4, even as the user's head moves. The WAC display system is compatible with NVGs, and it can provide realistic depth cues when the simulated height of the simulated aircraft exceeds approximately 15 feet from the simulated ground. However, if the simulated height is less than approximately 10 feet, the depth cues of the image provided by the WAC display system become unrealistic. Another known problem with the WAC display system is its relatively small horizontal field of view (less than approximately 25°) and vertical field of view (less than 15°). Other problems with the chin window WAC display system are its limited brightness and its higher cost compared to real-image display systems 20.

[0011] A major drawback of both types of conventional downward-facing window displays is that their focal length is fixed and they can only be optimized for one viewing distance. For example, in a simulation where an aircraft descends from a high-altitude hover (simulated height 28 to approximately 30 feet) to landing, a real-image display system with a viewing distance of approximately 6 to 8 feet is unrealistic for the first 90% of the descent. Similarly, a downward-facing window WAC display system is unrealistic for the final part of the descent from approximately 30 feet to landing. Thus, conventional downward displays are inaccurate for a significant portion of simulated landing or takeoff procedures. The visual errors described for both real-image and WAC display systems mean that users may misjudge descent speed and altitude on the terrain using either type of display, potentially resulting in hard landings and difficulty maintaining the hovering position. These shortcomings severely limit the realism and usefulness of conventional simulators.

[0012] Therefore, a system and method are required to adjust the focal length of the simulator image in real time. [Overview of the project]

[0013] One aspect of the present disclosure provides a system for adjusting the focal length of an image displayed to a user at a specified viewpoint. The system comprises (1) a screen for displaying an image depicting an object, (2) a mirror spaced at a variable distance from the screen for reflecting the image displayed by the screen to a specified viewpoint, and (3) an adjuster for adjusting the distance between the screen and the mirror.

[0014] In some embodiments, the system further includes a control system that communicates with a tuner, the control system causing the tuner to perform (a) determine the focal length of an image based on a simulated distance between a given viewpoint and an object in the image; (b) determine the simulated size of an object based on the simulated distance; (c) generate commands to the tuner to adjust the distance between the screen and the mirror to achieve the focal length; and (d) adjust the size of an object in the image based on the determined simulated size.

[0015] The system may include one or more of the embodiments described above, and optionally, the control system may further (1) generate an image and (2) determine the simulated size of an object.

[0016] In some embodiments, the screen is at least one of a liquid crystal display, an organic light-emitting diode display, a liquid crystal display on silicon, a light-emitting diode display, a quantum dot display, and a plasma display.

[0017] The system may include one or more of the embodiments described above, in some embodiments the system further comprises a projector that projects an image onto a screen, the screen being one of a front projection screen and a rear projection screen.

[0018] In embodiments where the screen is a rear projection screen, the projector is positioned to project an image onto the back of the screen, with the front of the screen facing the mirror. In this embodiment, the rear projection screen may be positioned at least partially between the mirror and the projector.

[0019] Alternatively, if the screen is a front projection screen, the projector is positioned to project an image onto the front of the screen, with the front of the screen facing the mirror. In this embodiment, the projector may be positioned at least partially between the mirror and the front projection screen.

[0020] In one or more embodiments, the front surface of the screen facing the mirror is convex.

[0021] Alternatively, the front surface of the clean has a shape that includes at least part of a circle, sphere, parabola, ellipse, plane, freeform, and combinations thereof.

[0022] In some embodiments, the projector is at a fixed distance from the screen, and the regulator moves the screen and the projector.

[0023] In some embodiments, the adjuster includes a motor that moves at least one of the screen and the mirror to adjust the distance.

[0024] In other embodiments, the mirror is fixed, or it is at a certain distance from a designated viewpoint.

[0025] The system may include one or more of the embodiments described above, and optionally, the screens are interconnected to the regulating platform, and the platform is movable.

[0026] The system may include one or more of the embodiments described above, and optionally, the platform moves to adjust the distance between the screen and the mirror.

[0027] In some embodiments, the adjuster comprises a stopper that prevents the screen from contacting the mirror.

[0028] In some embodiments, the distance between the screen and the mirror correlates with the focal length.

[0029] In some embodiments, the screen is at a first distance from the mirror and has a first position where the focal length is at infinity.

[0030] Alternatively, at the first position, the light rays reflected from the mirror are substantially parallel.

[0031] At a second position, the screen is at a second distance from the mirror and the focal length is shorter than infinity. The first distance is longer than the second distance.

[0032] In some embodiments, the system includes one or more of the foregoing features, and optionally, the mirror is reflective and has a front face directed towards a specified viewpoint and the screen. The front face of the mirror has a shape that collimates light from the screen when the screen is at a predetermined distance from the mirror.

[0033] The front face of the mirror is optionally concave.

[0034] Alternatively, the front face of the mirror has an adjustable shape.

[0035] Alternatively, the front face of the mirror has a shape that includes at least a portion of a circle, sphere, parabola, ellipse, plane, freeform, and combinations thereof.

[0036] The system can include any one or more of the foregoing embodiments, and optionally, the system is associated with a simulator such as a flight simulator.

[0037] In some embodiments, the simulator is an aircraft simulator and includes a downward window positioned between a designated viewpoint and a mirror.

[0038] In at least one embodiment, the image displayed by the screen is visible to the user through a lower window.

[0039] Other aspects of the present disclosure provide a control system for a simulator that adjusts the focal length of an image displayed to a user at a specified viewpoint of the simulator. The control system may include (1) a processor and (2) a memory that stores instructions to be executed by the processor. When an instruction is executed, the processor performs the following: (a) generating an image that is reflected by a mirror and displayed by a screen that is positioned and directed toward a specified viewpoint; (b) determining a simulated distance from the specified viewpoint to an object in the image; (c) determining the focal length of the image based on the simulated distance; (d) determining the simulated size of the object based on the simulated distance; (e) generating instructions to an adjuster that adjusts the distance between the screen and the mirror to achieve the focal length; and (f) adjusting the size of the object in the image based on the determined simulated size.

[0040] Optionally, determining a simulated distance includes one or more of the following: (1) receiving the position of a specified viewpoint; (2) determining the simulated position of an object relative to the specified viewpoint; and (3) determining the distance between the position of the specified viewpoint and the simulated position of the object.

[0041] In some embodiments, the control system includes one or more of the embodiments described above, where the distance between the screen and the mirror correlates with the focal length.

[0042] In the first position, the screen is at a first distance from the mirror, and the focal length is infinity. In the second position, the screen is at a second distance from the mirror, and the focal length is less than infinity. The first distance is longer than the second distance.

[0043] The control system may include one or more of the embodiments described above, and optionally, the memory includes an instruction to maintain the screen at a first position which is a first distance from the mirror if the simulated distance is greater than a predetermined threshold. In some cases, the predetermined threshold is about 30 feet. In other embodiments, the predetermined threshold is greater than 30 feet or less than 30 feet.

[0044] The control system may include one or more of the embodiments described above and may further include an instruction to move the screen to a second position which is a second distance from the mirror when the simulated distance is less than a predetermined threshold.

[0045] In some embodiments, the simulator simulates an aircraft. The simulator optionally includes a downward window positioned between a designated viewpoint and a mirror, so that the image displayed on the screen is visible to the user through the downward window.

[0046] Another aspect of the present disclosure provides a method for adjusting the focal length of an image at a given viewpoint, the method comprising: (1) generating an image to be displayed on a screen oriented so that the image is reflected at a given viewpoint by a mirror of a simulator; (2) determining a simulated distance between the given viewpoint and the simulated positions of objects in the image; (3) determining the focal length of the image based on the simulated distance; (4) determining the simulated size of objects based on the simulated distance; (5) generating commands to an adjuster to change the distance between the screen and the mirror to achieve the focal length; and (6) adjusting the size of objects in the image based on the simulated size.

[0047] Optionally, this method may further include receiving the position of a specified viewpoint.

[0048] In some embodiments, the screen and mirror are associated with a simulator that simulates an aircraft.

[0049] The simulator optionally includes a downward window positioned between the specified viewpoint and the mirror.

[0050] In some embodiments, the image displayed on the screen is visible to the user through a lower window.

[0051] This method may include one or more of the embodiments described above, and may further include maintaining the screen at a first position, which is a first distance from the mirror, when the simulated distance is greater than a predetermined threshold. At the first position, the light rays reflected from the mirror are substantially parallel, and the focal length of the image is at infinity.

[0052] In some examples, the given threshold is approximately 30 feet. In other embodiments, the given threshold is greater than 30 feet or less than 30 feet.

[0053] In some embodiments, the method further includes moving the screen to a second position, which is a second distance from the mirror, when the simulated distance is less than a predetermined threshold. At the second position, the light rays reflected from the mirror are not parallel, and the image has a fixed focal length shorter than infinity.

[0054] This method may include one or more of the embodiments described above, and optionally includes moving the screen away from the mirror to a first position which is a first distance from the mirror, when the simulated distance increases from below a predetermined threshold to above a predetermined threshold.

[0055] Alternatively, this method may further include moving the screen to a second position toward the mirror when the simulated distance decreases from a value greater than a predetermined threshold to a value less than a predetermined threshold.

[0056] Another embodiment is a flight simulator for a student training in aircraft operation, comprising: (1) a first display system for simulating a first view from an aircraft window; and (2) a variable sighting display system for simulating a second view of the outside of the aircraft as seen through a downward window positioned near the floor of the simulator's cabin. The first display system comprises (a) a projector, (b) a first screen, and (c) a mirror array for reflecting the first image to a designated viewpoint of the simulator, wherein the projector is operable to generate the first image displayed on the first screen. The variable sighting display system comprises (i) a second screen for displaying a second image, (ii) mirrors for reflecting the second image from the second screen to a designated viewpoint through a downward window, and (iii) an adjuster for moving the second screen relative to the mirrors.

[0057] In some embodiments, when the second screen is at a first distance from the mirror, the second image is at infinity focus. Optionally, when the second screen is at a first distance from the mirror, the light rays reflected from the mirror are substantially parallel.

[0058] In at least one embodiment, the front surface of the second screen facing the mirror has a shape that includes at least a portion of circles, spheres, parabolas, ellipses, planes, freeform shapes, and combinations thereof.

[0059] Optionally, when the second screen is at a second distance from the mirror, the second image has a fixed focal length less than infinity, and the second distance is less than the first distance.

[0060] The flight simulator may include one or more of the embodiments described above, and optionally, the mirror is at a fixed distance from the specified viewpoint.

[0061] In some embodiments, the second screen is at least one of a liquid crystal display, an organic light-emitting diode display, a liquid crystal display on silicon, a light-emitting diode display, a quantum dot display, and a plasma display.

[0062] The flight simulator may include one or more of the embodiments described above, in some embodiments the variable sighting display system further comprises a second projector that projects a second image onto a second screen, the second screen being one of a front projection screen and a rear projection screen.

[0063] In embodiments where the second screen is a rear projection screen, the second projector is positioned to project the second image onto the back of the second screen, with the front of the second screen facing the mirror. In this embodiment, the rear projection screen is positioned at least partially between the mirror and the second projector.

[0064] Alternatively, if the second screen is a front projection screen, the second projector is positioned to project the second image onto the front of the second screen, with the front of the second screen facing the mirror. In this embodiment, the second projector is positioned at least partially between the mirror and the front projection screen.

[0065] In some embodiments, the second projector is at a fixed distance from the second screen, and the regulator moves the second screen and the second projector.

[0066] In some embodiments, the adjuster includes a motor that moves at least one of the second screen and the mirror to adjust the distance between the second screen and the mirror.

[0067] In other embodiments, the mirror is fixed in place.

[0068] The flight simulator may include one or more of the embodiments described above, and optionally, a second screen may be interconnected to a platform of adjustment devices, the platform of which is movable.

[0069] The flight simulator may include one or more of the embodiments described above, optionally, the platform moves and adjusts the distance between the second screen and the mirror.

[0070] In some embodiments, the adjuster includes a stopper to prevent the second screen from coming into contact with the mirror.

[0071] In some embodiments, the distance from the second screen to the mirror correlates with the focal length.

[0072] In some embodiments, the flight simulator includes one or more of the features described above, and optionally, the mirror has a reflective front facing a designated viewpoint and a second screen. The front of the mirror has a shape that collimates light from the second screen when the second screen is at a predetermined distance from the mirror.

[0073] The front surface of the mirror is optionally concave.

[0074] In some embodiments, the front surface of the mirror has a shape that includes at least some of a circle, a sphere, a parabola, an ellipse, a plane, a freeform shape, and combinations thereof.

[0075] Alternatively, the front of the mirror has an adjustable shape.

[0076] In some embodiments, the flight simulator includes one or more of the embodiments described above and further comprises a control system that communicates with a regulator.

[0077] Alternatively, the control system may be operated to perform one or more of the following operations: (a) determine the focal length of the second image based on the simulated distance from a specified viewpoint to an object in the second image; (b) determine the simulated size of an object based on the simulated distance; (c) generate commands to adjust a tuner to adjust the distance between the second screen and a mirror to achieve the focal length; and (d) adjust the size of an object in the second image based on the determined simulated size.

[0078] Alternatively, the control system may generate a second image.

[0079] This summary is not intended to represent, nor should it be construed to represent, the entire scope and scope of the Disclosure. The Disclosure is described at various levels of detail in the summary, accompanying drawings, and detailed description, and the inclusion or exclusion of elements, components, etc., in this summary is not intended to limit the scope of the Disclosure. Additional aspects of the Disclosure are made clearer from the detailed description, particularly in conjunction with the drawings.

[0080] As used herein, the terms “at least one,” “one or more,” and “and / or” are open-ended expressions that are both conjugated and selective in use. For example, the expressions “at least one of A, B, and C,” “at least one of A, B, or C,” “one or more of A, B, and C,” “one or more of A, B, or C,” and “A, B, and / or C” mean A only, B only, C only, a combination of A and B, a combination of A and C, a combination of B and C, or a combination of A, B, and C, respectively.

[0081] As used herein, the words "a" or "an" refer to one or more entities. Thus, the words "a" (or "an"), "one or more," and "at least one" are interchangeable in this specification.

[0082] Unless otherwise specified, all numerical values ​​used in the specification and claims to represent quantities, dimensions, conditions, ratios, ranges, etc., shall be understood in all cases to be modified by the word “about” or “approximately.” Accordingly, unless otherwise specified, all numerical values ​​used in the specification and claims to represent quantities, dimensions, conditions, ratios, ranges, etc., may be increased or decreased by about 5% to obtain a satisfactory result. Furthermore, if the meaning of the terms “about” or “approximately” as used herein is not obvious to a person skilled in the art, the terms “about” and “approximately” shall be interpreted to mean within plus or minus 5% of the stated value.

[0083] All ranges described herein can be reduced to any subrange or portion of a range, or any value within a range, without departing from the present invention. For example, the range "5-55" includes, but is not limited to, the subrange "5-20" and "17-54".

[0084] As used herein, “contains,” “includes,” “have,” and their variations mean to encompass the items listed thereafter, their equivalents, and any additional items. Therefore, “contains,” “includes,” “have,” and their variations are interchangeable within this specification.

[0085] As used herein, the term “means” shall be understood to be interpreted as broadly as possible in accordance with § 112(f) of the United States Patent Act. Accordingly, any claim containing the term “means” shall cover all structures, materials, or acts and their equivalents described herein. Furthermore, structures, materials, or acts and their equivalents shall include all those described in the summary, brief description of the drawings, detailed description, abstract, and the claims themselves.

[0086] The accompanying drawings are incorporated herein and constitute part thereof, illustrating embodiments of the disclosed system and, together with the general description of the above disclosure and the detailed description of the drawings below, are useful in illustrating the principles of the disclosed system and device. [Brief explanation of the drawing]

[0087] [Figure 1] Figure 1 is a schematic side view of a conventional simulator equipped with a real-image display system located outside the lower window. [Figure 2] Figure 2 is a schematic side view of a simulator equipped with a variable sighting display system according to an embodiment of the present disclosure. [Figure 3] Figure 3 is an isometric view of a portion of the simulator shown in Figure 2. [Figure 4A] Figure 4A is a schematic side view of the variable sighting display system of a simulator according to the present disclosure. [Figure 4B] Figure 4B is a schematic side view of a variable sighting display system of a simulator according to another embodiment of the present disclosure. [Figure 4C] Figure 4C is a schematic side view of a variable sighting display system for a simulator according to some embodiments of the present disclosure. [Figure 5A] Figure 5A is a schematic side view of the simulator in Figure 2 when it is at the first simulated height above the ground. [Figure 5A] Figure 5B is another schematic side view of the simulator in Figure 2 when it is at a second simulated height which is less than the first simulated height from the ground. [Figure 6] Figure 6 is a schematic diagram of a control system for adjusting the focal length of an image according to some embodiments of this disclosure. [Figure 7] Figure 7 is a flowchart showing a method for adjusting the focal length of an image according to some embodiments of this disclosure. [Figure 8] Figure 8 is another flowchart schematically illustrating a method for determining a simulated distance according to at least one embodiment of the present disclosure. [Modes for carrying out the invention]

[0088] The drawings are not necessarily to scale (although they may be). In some cases, details not necessary for understanding the disclosure, or details that obscure other details, may be omitted. Of course, it should be understood that the disclosure is not necessarily limited to the embodiments described herein. As should be understood, other embodiments are possible by using one or more of the features described above or below, either alone or in combination. For example, various features and devices shown and / or described in reference to one embodiment can be combined with or replaced with features or devices of other embodiments, regardless of whether such combinations or substitutions are specifically shown or described herein.

[0089] Referring to Figures 2-6, a simulator 40 comprising a variable chin display system 62 according to an embodiment of this disclosure is schematically shown. The variable chin display system 62 may be referred to herein as a variable display or chin display. The variable display 62 is operable to adjust the focal length of an image 64 displayed to a user 30 (e.g., a student) at a designated viewpoint 32 of the simulator 40.

[0090] Referring to Figure 2, a simulator 40 equipped with a variable sighting display system 62 according to an embodiment of the present disclosure is schematically shown. The simulator 40 may be an aircraft simulator for training a user 30 to operate an aircraft that includes a downward window 46. The aircraft may be a fixed-wing aircraft, a helicopter, a tiltrotor aircraft, or any other aircraft with a downward window. However, it will be understood that the variable sighting display system 62 can be used in simulators that simulate the operation of any type of vehicle. Simulators 40 of any size and type of mobile equipment and vehicle include, for example, cars, trucks, trains, tracked vehicles (such as tanks and construction vehicles), ships, and spacecraft, and the simulator 40 may include the variable sighting display system 62 according to an embodiment of the present disclosure. The variable sighting display system can also be used in games or other systems where it may be necessary to adjust or change the focal length of the image displayed to the user.

[0091] The simulator includes a main display 48 that operates in conjunction with a variable sighting display system 62. The main display includes a projector 50 that projects an image 56 onto a screen 52. The image 56 is seen by the user 30 as a reflection of a mirror array 54. The image 56 on the main display 48 is seen by the user as collimated rays 58 and is viewed at a far-field focus. The image 56 includes an object 60 located outside the simulated cockpit and at a simulated position, as seen by the user as indicated by the first arrow 34. In the example in Figure 2, the object 60 is a tree.

[0092] Image 56 (and the object 60 shown in the image) may be at infinity, with a focal length exceeding approximately 30 feet. Therefore, the collimated rays 58 of the image are nearly parallel to each other.

[0093] The variable sighting display system 62 projects another image 64 through the lower window 46 of the simulator 40. The user 30 can view the image 64 through the lower window 46, as schematically shown by the second arrow 36.

[0094] The downward window 46 is positioned between the designated viewpoint 32 from which the user 30 is positioned within the simulator 40 and the mirror 74 of the variable sighting display system 62. The downward window 46 is typically positioned on or near the floor of the simulator 40 and is used by the user 30 during simulations of the simulated aircraft's takeoff, landing, and / or hovering. It will be understood that the variable sighting display system 62 can also be used during other simulated procedures.

[0095] A variable sighting system typically includes a mirror 74 and a screen 68. In some embodiments, the variable sighting display system 62 includes a projector 80, as shown in Figure 2. The projector 80 and screen 68 may have different arrangements in other embodiments described herein, as schematically shown in Figure 4B. Furthermore, in some embodiments of this disclosure (for example, as described in relation to Figure 4C), the screen is self-illuminating, so the variable sighting system 62 does not include a separate projector 80. During use, the projector 80 (or screen 68) projects an image 64 that the user 30 sees as a reflection of the mirror 74.

[0096] In all embodiments of the variable sighting display system 62, image 64 is aligned with image 56 of the main display 48. Thus, as schematically shown in Figure 2, images 56, 64 of the main display 48 and the tree 60 in the variable sighting display system 62 are aligned with each other from the viewpoint of the user 30 at a given viewpoint. Furthermore, a control system 122 communicating with the main display 48 and the variable sighting display system 62 can change the simulated size 106 of the object 60 in the image as the simulated height 102 of the aircraft from the ground 26 changes (as schematically shown in Figures 5A and 5B).

[0097] Figure 3 schematically shows a variable sighting display system 62 according to several embodiments for the cockpit 42 of the simulator 40. The cockpit 42 may include a window 44 associated with a main display 48. The variable sighting display system 62 is positioned to display an image 64 through a lower window 46. Although only one variable sighting display system 62 is shown, the simulator 40 may have a second variable sighting display system associated with a second lower window on the opposite side of the cockpit 42.

[0098] In some embodiments, the cockpit 42 may include an upper window 45. Alternatively, the simulator 40 may include a variable sighting display system associated with one or more upper windows 45. Furthermore, the variable sighting display system may be associated with any window of the cockpit, such as a side window or a lower side window.

[0099] Referring to Figures 4A–4C, embodiments of a simulator 40 equipped with the variable sightline display system 62 of the present disclosure are schematically illustrated. In all embodiments, the variable sightline display system is operable to adjust or change the focal length of an image 64 displayed to the user 30 based on a simulated or perceived distance 100 (also called “slant distance” or “line of sight distance”) between the user’s designated viewpoint 32 and an object 60 outside the simulated environment or simulated vehicle.

[0100] The variable sighting display system 62 comprises a screen 68, a mirror 74, and an adjuster 82. The screen 68 is configured and operable to display an image 64. The mirror 74 is configured and operable to reflect the image displayed by the screen 68 to a designated viewpoint 32. Although the variable sighting display system is shown to be used with the lower window 46, it will be understood that the variable sighting display system can be used for any display visible through any window of the simulator and in any simulated environment.

[0101] The focal length of the variable sighting display system 62 is adjusted by a regulator 82. The regulator 82 is operable to change the distance 96 between the screen 68 and the mirror 74. As the focal length changes, the size or height 106 of the objects 60 that appear in the image 64 displayed on the screen may be adjusted by the simulator's control system 122, as described herein. The control system 122 communicates with the regulator 82 and one or more components of the variable sighting display system, such as the projector 80.

[0102] The mirror 74 has a rear surface 76 and a front surface 78 opposite the rear surface. The front surface 78 of the mirror is oriented toward the lower window and the front surface 72 of the screen 68 and is adapted to reflect light from the screen to a specified viewpoint. In this way, the user 30 views the image 64 on the reflective front surface 78 of the mirror 74.

[0103] The mirror 74 and its front surface 78 may be of any shape and size. For example, the mirror 74 may be curved or flat. In some embodiments, the front surface 78 of the mirror may have a shape that includes at least some of a circle, a sphere, a parabola, an ellipse, a plane, a freeform shape, and combinations thereof. In some embodiments, the front surface 78 may be described as being generally concave.

[0104] The front surface 78 of the mirror has a shape that collimates light from the screen 68 when the screen is at a predetermined distance from the mirror 74.

[0105] Alternatively, the front surface 78 of the mirror may be substantially rigid. In addition, or instead, the front surface 78 of the mirror may have an adjustable shape.

[0106] In some embodiments, the mirror 74 may include multiple mirrors. In such embodiments, the multiple mirrors may include a combination of curved mirrors and / or flat mirrors.

[0107] In at least one embodiment, the mirror 74 is fixed to the lower window 46, and the screen 68 is movable by an adjuster 82. In such an embodiment, the mirror 74 is at a fixed distance from a designated viewpoint 32.

[0108] The adjuster 82 is configured and operable to change the distance 96 between the front surface 72 of the screen 68 and the front surface 78 of the mirror. Thus, the distance 96 is variable. The adjuster 82 can move the screen 68 in any way known to those skilled in the art.

[0109] In some embodiments, the regulator 82 includes a platform 84 that is movable relative to the mirror 74. More specifically, the platform can move toward or away from the mirror 74, as schematically shown by arrow 86.

[0110] Alternatively, in at least one embodiment, the regulator 82 moves the screen 68 along the optical centerline (or optical axis) of the mirror 74. However, in other embodiments, the regulator 82 can move the screen 68 along a different axis relative to the mirror.

[0111] The screen 68 may be fixed to the platform 84. Thus, the screen 68 moves toward or away from the mirror 74 along with the platform 84, as indicated by arrow 86. Any suitable means for fixing a screen to a platform, known to those skilled in the art, may be used with the variable display 62 of this disclosure. In some embodiments, the screen 68 is fixed to the platform by a mount or stand 88.

[0112] Alternatively, the stand 88 can be operated to change the orientation of the screen 68 relative to one or more of the platform 84 and mirrors 74. In this way, the orientation of the front surface 72 of the screen 68 can be changed as the platform 84 changes the distance 96 between the screen and the mirrors. In some embodiments, the stand 88 can rotate the screen about the vertical axis of the stand. In addition, or instead, the stand can swivel the screen about the vertical axis.

[0113] The adjuster 82 includes an actuator 92 that moves the platform 84. The actuator 92 can move the platform 84 toward or away from the mirror in response to a signal from the control system 122. It will be understood that the adjuster 82 can move any component or any combination of components of the variable sighting display system 62.

[0114] The actuator may include any suitable means known to those skilled in the art that can be operated to change the position of the platform 84 relative to the mirror. In some embodiments, the actuator 92 includes a motor. In addition, or instead, the actuator may include tracks, rails, wheels, gears, pistons, servo drives, worm drives, belts, cables, etc. In some embodiments, the adjuster 82 may include a track on which the screen 68 moves or slides to adjust the distance 96.

[0115] In some embodiments, the regulator 82 includes a motor that moves the screen 68. It will be understood that the motor can move the mirror 74 and / or the projector 80.

[0116] In some embodiments, the adjuster 82 may alternatively include a stop 94. The stop 94 prevents the screen 68 from unintentionally or carelessly coming into contact with the mirror 74. For example, the stop 94 maintains a predetermined minimum distance 96 between the screen 68 and the mirror 74. In this way, the stop 94 can prevent the screen 68 from coming into contact with the mirror 74.

[0117] The stop 94 may be associated with the platform 84. Alternatively, the stop may be associated with the actuator 92. Other means of preventing the screen from moving less than a predetermined distance 96 from the mirror may be used in conjunction with the variable sighting display system 62 of this disclosure.

[0118] Referring to Figures 4A and 4B, in some embodiments, the variable sighting display system 62 also includes a projector 80 that projects the image 64 onto a screen 68A. In some embodiments, the projector 80 has a lens with a fixed focal length. Alternatively, the projector 80 may include an optical system such as one or more lenses and / or mirrors so that the focal length can be adjusted and / or the size of the object 60 in the image 64 can be adjusted.

[0119] The projector 80 may be fixed to the platform 84. Therefore, the projector 80 may move with the platform 84 as the platform adjusts the position of the screen 68A relative to the mirror 74. Any suitable means for fixing the projector to the platform known to those skilled in the art may be used. In some embodiments, the projector 80 is fixed to the platform by a mount 90.

[0120] In some embodiments, the projector 80 is positioned at a fixed distance 98 from the screen 68A. Specifically, in some embodiments, the distance 98 between the projector and the screen does not change and is substantially constant. In these embodiments, the regulator 82 moves both the screens 68A-1, 68A-2 and the projector 80 substantially simultaneously.

[0121] Alternatively, in at least one embodiment, the distance 98 between the projector 80 and the screens 68A-1, 68A-2 can also be changed by the adjuster 82.

[0122] The screen 68A may have any shape. In some embodiments, the screen may be curved or flat. The back surface 70 of the screen 68A may be concave, and the opposite front surface 72 may be convex. In some embodiments, the screens 68A-1, 68A-2, and 68B have shapes including at least some circles, spheres, parabolas, ellipses, planes, freeform shapes, and combinations thereof.

[0123] In embodiments where the variable aiming display system 62 includes a projector 80, the screen 68A may be a rear projection screen 68A-1 (shown in Figure 4A) or a front projection screen 68A-2 (shown in Figure 4B).

[0124] As shown in Figure 4A, in an embodiment where screen 68A-1 is a rear projection screen, the projector 80 is positioned to project an image 64 onto the back 70 of screen 68A-1. The image 64 is seen on the front 72 of screen 68A-1 and then reflected by the front 78 of the mirror.

[0125] In some embodiments, the screen 68A-1 is formed of a transparent or substantially transparent material. For example, the screen 68A-1 may be acrylic or glass. Optionally, the screen 68A-1 is treated to diffuse light from the projector 80. In some embodiments, the screen 68A-1 includes a diffusion coating or film. In some embodiments, the film or coating is applied to a convex front surface 72 to focus the image 64 onto the screen 68A-1.

[0126] As shown in Figure 4B, in embodiments where screen 68A-2 is a front projection screen, the projector 80 is positioned to project the image 64 onto the front surface 72 of screen 68A-2. In some embodiments, the projector 80 may be positioned at least partially between the front surface 72 of screen 68A-2 and the mirror 74.

[0127] The image 64 generated by the projector 80 is reflected from the front 72 to the mirror 74. The screen 68A-2 may be formed of an opaque material. In some embodiments, the screen 68A-2 is formed of glass, plastic, fiberglass, metal, or a similar material.

[0128] Those skilled in the art will understand that any arrangement of the projector 80, screen 68, and mirror 74 is within the scope of this disclosure. In some embodiments, the variable sighting display system 62 can be used with a simulator 40 having screens 68 and mirrors 74 of different configurations and arrangements. For example, a curved screen 68 can be used with a flat mirror 74, a curved mirror 74 can be used with a flat screen 68, and / or a curved mirror 74 can be used with a curved screen 68. In one embodiment, the screen 68 and mirror 74 are generally concave and curved in two or more dimensions.

[0129] Referring to Figure 4C, in other embodiments, the variable sight display system 62 does not include the projector 80. In these embodiments, the screen 68B is a self-emissive screen and may include elements of a projector that project an image 64 from the front surface 72 of the screen 68B. Thus, the screen 68B projects an image from its front surface 72. The image 64 is then reflected by the front surface 78 of the mirror 74. The screen 68B can be any type of display capable of projecting an image, such as a self-emissive curved screen, a set of LED panels, a liquid crystal display, an organic light-emitting diode display, a liquid crystal display on silicon, a light-emitting diode display, a quantum dot display, or a plasma display.

[0130] Referring to Figure 4C, the variable sight display system 62 does not include a projector 80. In these embodiments, the screen 68B is a self-illuminating screen and may include elements of a projector that project an image 64 from the front surface 72 of the screen 68B. Thus, the screen 68B projects an image from its front surface 72. The image 64 is then reflected by the front surface 78 of the mirror 74. The screen 68B can be any type of display capable of operating to project an image, such as a self-illuminating curved screen, a set of LED panels, a liquid crystal display, an organic light-emitting diode display, a liquid crystal display on silicon, a light-emitting diode display, a quantum dot display, or a plasma display. As shown in Figures 5A and 5B, during use of the variable sight display system, the image 64 is projected onto the screen 68 (whether self-projected or projected by the projector 80), and the image is seen by the user 30 as a reflection of the mirror 74. The image 64 is seen by the user 30 as a ray 66 with a predetermined focus. Ray 66 is collimated (as shown in Figure 5A) and appears at a focal length of infinity. Alternatively, by changing the position of the screen 68 relative to the mirror using the adjuster 82, the ray 66 in the image appears to the user 30 at a fixed focal length. As the screen 68 moves closer to the mirror 74 and the distance 96 decreases, the ray 66 diverges and its focal point becomes less than infinity (as schematically shown in Figure 5B).

[0131] The distance 96 from screen 68 to mirror 74 correlates with the focal length of the image 64 as seen by user 30. To elaborate further, the distance 96 (or focal length) is determined based on a simulated distance 100 from a given viewpoint 32 to an object 60 depicted in image 64. The simulated distance is the perceived viewing distance. In other words, the simulated distance may be the distance between a given viewpoint 32 and the object 60 as perceived by a user at the given viewpoint, assuming the object physically exists. The simulated distance 100 is also called the "slant distance," "perceived distance," or "line of sight distance."

[0132] When the screen 68 is in a first position (as shown in Figure 5A), the mirror 74 is at a first distance 96A from the screen and its focal length is at infinity. Thus, the light rays 66 reflected from the mirror are substantially parallel and the image 64 is collimated. An object 60 in the image 64 may be at a first distance 100A from a given viewpoint and displayed at a first simulated size or height 106A.

[0133] Referring to Figure 5B, at the second position of the screen 68, the mirror 74 is at a second distance 96B from the screen 68, and its focal length is less than infinity. The second distance 96B is less than the first distance 96A. At the second position, the ray 66 diverges slightly, as schematically shown in Figure 5B.

[0134] Figure 5B also shows a second distance 100B between the designated viewpoint 32 and the object 60 in image 64, where the second distance 100B is less than the first distance 100A. Therefore, in Figure 5B, because the designated viewpoint 32 is close to the object 60, the object 60 in image 64 may be displayed with a second simulated size or height 106B. The second height 106B is greater than the first height 106A shown in Figure 5A.

[0135] In some embodiments, if the simulated distance 100 exceeds a predetermined threshold, the screen 68 remains at a first position from the mirror 74 (i.e., a first distance 96A). In some embodiments, the predetermined threshold is approximately 30 feet. In other embodiments, the predetermined threshold may be less than 30 feet or greater than 30 feet.

[0136] The adjuster 82 may move the screen 68 to a second position from the mirror 74 (i.e., a second distance 96B) if the simulated distance 100 satisfies a predetermined threshold. In at least one example, the predetermined threshold correlates with the height of the simulated aircraft (e.g., a helicopter) on the terrain 102, where the focal length changes from infinity to less than infinity.

[0137] An example of a simulated scenario in which a predetermined threshold can be met is a landing simulation. For example, in the case of a simulated aircraft that exceeds a predetermined threshold, the focal length of the image 64 seen by user 30 is infinity. Thus, the tuner 82 can move the screen 68 to a first position at a first distance 96A from the mirror 74, as schematically shown in Figure 5A.

[0138] As the simulated aircraft descends toward the landing surface, the altitude 102B decreases, and the simulated aircraft reaches a predetermined threshold. As schematically shown in Figure 5B, the tuner 82 may move the screen 68 from a first position to a second position 96B, reducing the first distance to the second distance 96B, thereby changing the focal length of the image 64 seen by the user 30 to less than infinity. As the simulated aircraft continues to descend, the tuner 82 may move the screen 68 to a third position closer to the mirror 74 in order to continue adjusting the focal length of the image 64.

[0139] During a takeoff simulation, the opposite happens. For example, during a takeoff simulation, the adjuster 82 adjusts the distance 96 between the first distance 96A and the second distance 96B to change the focal length of the image 64 seen by the user 30 between infinity and less than infinity, or vice versa.

[0140] In one embodiment, as described with reference to Figure 6, the adjuster 82 can be automatically controlled by the controller 120 to move the screen 68 and adjust the distance 96 between the screen 68 and the mirror 74. In another embodiment, the adjuster 82 can be manually controlled by a user or operator via the control system 122.

[0141] Referring to Figure 6, the simulator 40 may include a control system 122 that communicates with a variable sighting display system 62. Suitable control systems 122 are known to those skilled in the art. In some embodiments, the control system 122 is, but is not limited to, a personal computer running the MS Windows® operating system, Mac OS®, Linux®, or other known operating systems. Alternatively, the control system may be a smartphone, tablet computer, laptop computer, and similar computing devices. In other embodiments, the control system is, but is not limited to, a data processing system including one or more of the following: input devices (keyboard, mouse, touchscreen, etc.), output devices (display, speaker, etc.), graphics card, communication devices (Ethernet® card, wireless communication device, etc.), permanent memory (hard drive, etc.), temporary memory (random access memory, etc.), computer instructions stored in permanent and / or temporary memory, and a processor.

[0142] In some embodiments, the control system 122 is integrated with or incorporated into the image generator associated with the simulator 40. The control system 122 may also be integrated with or incorporated into the simulator's host computer. In addition, or instead, the control system 122 may be a virtual machine running on (or operated by) the simulator's computer system. In yet another embodiment, the control system 122 is associated with a computer system that communicates with the image generator or the simulator 40's host computer system.

[0143] The control system 122 according to the embodiments of this disclosure may include a processor 124, memory 126, communication interface 128, and user interface 130. In some embodiments, the control system 122 may have more or fewer components than those shown in Figure 6. The control system 122 may be any suitable computer known to those skilled in the art.

[0144] The processor 124 of the control system 122 may be any processor known to those skilled in the art, including the processor described herein or a similar processor. The processor 124 may execute instructions stored in the memory 126, which may enable the processor 124 to perform one or more calculation steps using or based on data received from the variable sighting display system 62.

[0145] Memory 126 is or includes RAM, DRAM, SDRAM, other solid-state memory, any memory described herein, or other tangible non-temporary memory that stores computer-readable data and / or instructions. Memory 126 may store information or data useful for completing any operation described herein (including steps or operations of the method described herein 140 and / or 160). Memory 126 may store, for example, a focal length model 132, a size model 134, simulation software, an image engine or image generation software, and / or controller instructions 136. Such instructions may, depending on the embodiment, be organized into one or more applications, modules, packages, layers, or engines. The instructions cause the processor 124 to manipulate the data stored in memory 126 and / or data received from the variable sight display system 62.

[0146] In some embodiments, memory 126 includes a lookup table 138. Alternatively, in at least one embodiment, the lookup table 138 includes a defined distance 96 between the mirror 74 and the screen 68 for a plurality of predefined situations. In some embodiments, the lookup table includes a distance 96 based on the simulated height 102 of the simulated aircraft. Additionally, or instead, the lookup table may include a distance 96 at which the screen is separated from the mirror, based on a slope range or a simulated distance 100 from a given viewpoint 32 to an object 60 in the image 64.

[0147] For example, the lookup table 138 may indicate that when the simulated height 102A exceeds a predetermined amount, the regulator 82 should move the screen 68 to a first position at a first distance 96A (as schematically shown in Figure 5A). The lookup table 138 includes a value to reduce the distance 96 when the simulated height 102 is less than the predetermined amount. For example, if the simulated height 102 is 95% of the predetermined amount, the lookup table may include a second distance 96 expressed as a percentage of the first distance (95% of the first distance). Alternatively, the second distance 96 may be expressed as a distance (in inches or centimeters) subtracted from the first distance. Continuing this example, as the simulated height 102 continues to decrease, the lookup table may include a value to reduce the distance 96 between the screen and the mirror until a minimum distance 96 is reached, such as when a simulated aircraft is landing.

[0148] In some embodiments, the lookup table 138 can define a distance 96 between the screen 68 and the mirror 74 based on a simulated distance 100 from a designated viewpoint 32 to an object 60 in the image 64. For example, if the simulated distance 100 is greater than a predetermined amount, e.g., 18 feet, the lookup table may indicate that the screen should be at a first distance 96 from the mirror. As the simulated aircraft approaches the object, the lookup table may include a value that decreases the distance 96 so that the screen gradually moves closer to the mirror.

[0149] Including a predetermined value for distance 96 based on one or more of the simulated height 102 and the simulated distance 100 to object 60 is useful for supporting various flight operations. For example, during landing or takeoff simulations, it may be useful to determine the distance 96 between the screen and the mirror based on the simulated altitude 102 of the aircraft. However, in some simulations, such as high hovering beside object 60, the simulated height 102 may exceed a predetermined threshold, causing the screen 68 to be a sufficient distance 96 from the mirror 74, and the image 64 of the variable sighting display system to be focused at infinity. However, if the simulated aircraft is very close to object 60, the simulated distance 100 may be less than a predetermined amount. Therefore, to decrease the distance 96 and change the focal length of object 60 in the image 64, the screen must be moved toward the mirror.

[0150] The control system 122 may also include a communication interface 128. The communication interface 128 may be used to receive information from an external source (such as a variable sight display system 62) and / or to transmit commands, data, or other information to an external system or device (e.g., the tuner 82, the projector 80 (or screen 68B) and / or the variable sight display system, and the projector 50 of the main display 48). The communication interface 128 includes one or more wired interfaces (e.g., a USB port, an Ethernet port, a Firewire® port) and / or one or more wireless interfaces (e.g., configured to transmit information via one or more wireless communication protocols such as 802.11a / b / g / n, Bluetooth®, NFC®, ZigBee®). In some embodiments, the communication interface 128 serves to enable the control system 122 to communicate with one or more other processors 124 or other control systems 122 in order to reduce the time required to complete a computationally intensive task or for other reasons.

[0151] The control system 122 may also include one or more user interfaces 130. A user interface 130 may be, or include, a touchpad (e.g., one on a laptop computer), a keyboard, a mouse, a trackball, a monitor, a television, a touchscreen, a joystick, a switch, a button, and / or other device that receives information from and / or provides information to the user. A user interface 130 can be used, for example, to receive user selections or other user inputs regarding a focal length model 132, to receive user selections or other user inputs regarding a simulation performed by the simulator, to receive useful user inputs in relation to a controller instruction 136, and / or to display the instruction 136. In some embodiments, the user interface 130 may serve to allow a user or operator to modify an instruction 136, a tuner 82 (such as changing the position of the screen 68), or other displayed information, although it will be understood that each of the aforementioned inputs may be automatically generated by the control system 122 (e.g., a processor 124 or another component of the control system 122) or received by the control system 122 from an external source. In some embodiments, user input as described above may be alternative to or unnecessary for the operation of the systems, devices, and methods described herein.

[0152] Although the user interface 130 is shown as part of the control system 122, in some embodiments the control system 122 may utilize the user interface 130 housed separately from one or more other components of the control system 122. In some embodiments, the user interface 130 may be located near one or more other components of the control system 122, while in other embodiments, the user interface 130 may be located away from one or more other components of the control system 122.

[0153] Alternatively, as shown in Figure 6, the adjuster 82 may include a controller 120. The controller 120 controls the adjuster 82 so that it can move the screen 68 and change the distance 96 between the screen 68 and the mirror 74. In other embodiments, the adjuster does not include a controller 120.

[0154] The controller 120 may be an electronic, mechanical, or electromechanical controller. The controller 120 may have any of the processors described herein, or any other processor. The controller 120 may have a memory for storing instructions to perform any of the functions or methods described herein that are performed by the controller 120. In some embodiments, the controller 120 may simply convert signals received from the control system 122 (e.g., via the communication interface 128) into commands to operate the tuner 82. In other embodiments, the controller 120 may process and / or convert signals received from the tuner 82. Furthermore, the controller 120 may receive signals from one or more sources (e.g., the tuner 82) and output signals to one or more sources.

[0155] Referring to Figure 7, a method 140 is provided for adjusting the focal length of an image 64 displayed to the user 30 at a specified viewpoint 32 of the simulator 40. Method 140 can be performed, for example, using the components described above with respect to Figures 2-6.

[0156] Method 140 includes generating an image 64 to be displayed by the screen 68 of the variable sighting display system 62 in operation 142. The image may depict the environment outside a simulated vehicle (e.g., an aircraft) and may include objects 60 such as trees. The image 64 is transmitted to the projector 80 or screen 68B of the variable sighting display system.

[0157] In some embodiments, the projector 80 can project the image 64 onto the front 72 of screen 68A-2 (in the case of a front projection screen) or the back 70 of screen 68A-1 (in the case of a rear projection screen). In other embodiments where screen 68B is a self-emissive screen, the image is projected by screen 68B itself.

[0158] The image may be generated by the control system 122. For example, image 64 may be generated as part of simulation software stored in memory 126. In some embodiments, image 64 is created by image generation software stored in memory 126.

[0159] In some embodiments, the image 64 is received via a communication interface 128 from another control system, such as a control system that controls the simulator 40 and generates the image.

[0160] Method 140 also includes operation 144, which includes determining a simulated distance 100 from a designated viewpoint 32 to an object 60 in an image 64. The simulated distance may be a perceived viewing distance. In other words, the simulated distance may be the distance between a designated viewpoint 32 and the object 60 as perceived by the user 30 at the designated viewpoint, if the object were physically present. In some embodiments, the simulated distance may be (or associated with) a simulated height 102 of a simulated aircraft from the terrain. The height from the terrain 102 may be the distance between the simulated aircraft and the ground surface 26.

[0161] In some embodiments, the simulated distance 100 is determined using the Pythagorean theorem, inputting the height 102 of the simulated aircraft at a given viewpoint 32 and the horizontal distance 104 to the object 60. In some embodiments, the simulated distance may be determined using method 160 as described herein.

[0162] Method 140 also includes operation 146, which includes determining the focal length of an image 64 based on a simulated distance 100 between a designated viewpoint 32 and an object 60 in the image. In some embodiments, determining the focal length of an image includes using a focal length model 132 stored in the memory 126 of a control system 122. In such embodiments, a processor 124 can input the simulated distance 100 into the focal length model 132, run the focal length model 132, and receive the focal length as output from the focal length model 132. In some embodiments, the focal length model 132 can be trained, for example, using historical distances and / or simulated distances obtained from a simulation. In addition, or instead, operation 146 may include obtaining the focal length from a lookup table 138.

[0163] Method 140 may include an optional operation 148 that determines the simulated size 106 of the object 60 to be displayed in the image 64. In some embodiments, the simulator 40 determines the simulated size 106 of the object. More specifically, the simulator 40 may include a control system that executes a command to determine the simulated size of the object 60. The simulator control system then transmits a signal containing the simulated size to the communication interface 128. The control system 122 can then send a command to the projector 80 (or self-illuminating screen 68B) to project the image 64.

[0164] In some embodiments, the control system 122 inputs the simulated distance 100 into a size model 134 stored in memory 126. The size model then outputs the simulated size 106 to the control system 122 and its processor 124. Alternatively, the size model 134 may be trained using, for example, past distances and / or simulated distances obtained from simulations.

[0165] Method 140 may also include generating an instruction to a tuner 82 to change the distance 96 between the screen 68 and the mirror 74 in order to achieve the focal length in operation 150. Alternatively, operation 150 may include obtaining the distance 96 from a lookup table 138 based on one or more of the height from the terrain 102, the horizontal distance to the object 104, and the simulated distance 100 to the object in the image.

[0166] In some embodiments, a command is sent to the controller 120 to cause the adjuster 82 to adjust the distance 96. In embodiments in which the adjuster 82 includes an actuator 92, the controller 120 may control the actuator to move the screen 68 relative to the mirror 74, as described herein.

[0167] Method 140 may also include an operation 152 to adjust the size 106 of the object 60 in the image 64. The size of the object 60 in the image 64 may be adjusted based on the simulated size determined in operation 148. The size 106 of the object is adjusted to correspond to the adjustment of the distance 96 between the screen 68 and the mirror 74. The size of the object is also adjusted so that the object appears as a physical object at the focal length. In other words, the size 106 of the object is adjusted to match the perceived view of the object if it were physically visible to the user 30.

[0168] It will be understood that Method 140 may consist of more or fewer steps than those described above. One or more operations of Method 140 may be looped or repeated as needed, so that the focal length of the image 64 displayed to User 30 and the size 106 of the objects 60 visible in the image are continuously updated in real time. The focal length perceived by User 30 is adjusted to match the perceived distance 100 to the objects 60 displayed in the image 64. As described here, this is achieved by changing the distance 96 between the mirror 74 from which User 30 views the objects 60 and the screen 68 that displays the image 64 created by the control system 122. By manipulating the mirror / screen distance 96, the rays reflected from the mirror 74 can be adjusted from collimated (parallel rays) representing an infinity focus or distant objects (as shown in Figure 5A) to gradually diverging rays representing the focal length decreasing as the simulated aircraft approaches the object and / or the ground (as shown in Figure 5B). By adjusting the image's focal length in real time, the user's view of the environment becomes more accurate, especially during takeoff and / or landing procedures.

[0169] Referring to Figure 8, a method 160 for determining a simulated distance 100 is provided. Method 160 can be performed, for example, using the systems and components described above with respect to Figures 2-7. In some embodiments, method 160 is performed before method 140. In addition, or instead, method 160 may be performed during method 140. For example, method 160 may be performed before operation 146. Method 140 may be paused until method 160 is performed, and then resumed upon completion of method 160.

[0170] An alternative operation 162 of method 160 includes receiving the position of a designated viewpoint 32. In some embodiments, the position of the designated viewpoint 32 may be received as input from the user via the user interface 130. In other embodiments, the position of the designated viewpoint 32 may be determined by a sensor located near or on the designated viewpoint 32. For example, the user may wear a headset equipped with a sensor that transmits sensor data, including the position of the sensor, to the control system 122. In addition, or instead, the position of the designated viewpoint 32 may be obtained from the memory 126 of the control system 122.

[0171] Method 160 also includes, in operation 164, determining the simulated position of the object 60 depicted in the image 64 relative to a designated viewpoint 32. In some embodiments, determining the simulated position of the object may include determining the distance between the position of the designated viewpoint 32 and the mirror 74. In addition, or instead, the position of the object (or the simulated distance 100 to the object) may be received from the simulator 40, or as output of simulation software, or from an image generator that creates images for the simulator.

[0172] Method 160 may also include operation 166 to determine the distance between the position of a designated viewpoint 32 and the simulated position of the object 60 to obtain a simulated distance 100. The simulated position of the object is received from operation 164. In some embodiments, determining the distance includes subtracting the x and / or y coordinates of the designated viewpoint 32 from the x and / or y coordinates of the simulated position of the object 60.

[0173] It will be understood that Method 160 may involve more or fewer steps than those described above.

[0174] The methods and systems described herein use mirrors, screens, adjusters, and control systems to adjust the focal length of an image displayed to the user at a specified viewpoint in a simulator, and to adjust the focal length in real time. These methods and systems favorably adjust the focal length of an image when simulating the simulator moving closer to or further away from the image from a specified viewpoint. Such adjustment of focal length improves the realism of the image to the user and enhances the simulation experience, particularly during landing or takeoff simulations.

[0175] Another advantage of the method and system described herein is that the object 60 displayed in the image 64 of the variable sighting display system 62 aligns with (and corresponds to the size of) the object 60 displayed in the image 56 generated by the main display 48. This improves the realism of the simulation performed in the simulator.

[0176] The variable sighting display system 62 of the embodiments of the present disclosure offers the further advantage of being compatible with night vision goggles (NVGs) in situations where the NVGs are focused in an actual aircraft. More specifically, as those skilled in the art will understand, the NVGs used in the simulator 40 are focused at or near infinity to match the focus of the main “outside the window” display 48, just as in an actual aircraft that the simulator 40 replicates. This level of realism is important because it means that the instrument panel in the simulator cockpit 42 is out of focus with the NVGs, just as in an actual aircraft. To see the instrument panel in the simulator, the pilot 30 must be “trained to fly” and learn to glance under the night vision goggles to pick up instrument cues.

[0177] A variable sighting display system 62 associated with the lower window 46 of the simulator 40 of this disclosure can generate a near-infinity focus in several simulated flight situations (e.g., high-altitude hovering). Thus, when the screen 68 of the variable sighting display system is in a first position at a first distance 96A (illustrated in Figure 5A) from the mirror 74 to generate a near-infinity focus, the image 64 generated by the variable sighting display system 62 is NVG compatible (or in focus when viewed through an NVG). This is similar to how a pilot views an object through the lower window of a real aircraft (or helicopter) while hovering at high altitude.

[0178] When a real aircraft descends from a high-altitude hover, objects get closer and become out of focus in the NVGs. The pilot needs to glance below the NVGs to see objects through the downward-facing windows as the aircraft descends.

[0179] The variable sighting display system 62 can replicate this by moving the screen 68 to a second position at a second distance 96B (see Figure 5B) from the mirror 74. At this second position, the image 64 is less than infinity focus. The pilot user 30 then needs to look down through the night vision goggles and pick up ground cues through the simulator's lower window 46 (as in an actual aircraft). In this way, the variable sighting display system 62 of this disclosure builds positive habits and enhances the realism of the simulator 40.

[0180] As understood in light of the above disclosure, this disclosure includes methods comprising fewer steps than all of the steps identified in Figures 7 and 8 (and the corresponding descriptions of Methods 140 and 160), as well as methods comprising additional steps beyond those identified in Figures 7 and 8 (and the corresponding descriptions of Methods 140 and 160). While the general order of Methods 140 and 160 is shown in Figures 7 and 8, it will be understood by those skilled in the art that the steps of the methods can be arranged and performed in a different manner than those shown in Figures 7 and 8. Furthermore, while the steps of the methods may be described sequentially, many of the steps may actually be performed in parallel or simultaneously.

[0181] While various embodiments of the system are described in detail, it will be apparent to those skilled in the art that modifications and alterations of those embodiments will be conceivable. Such modifications and alterations will be expressly understood to be within the scope and spirit of this disclosure. Furthermore, it will be understood that the expressions and terms used herein are for illustrative purposes only and should not be considered limiting. The terms “includes,” “equipment,” and “has,” as used herein, and their variations thereof, shall encompass the items listed thereafter and their equivalents, as well as additional items.

[0182] Several variations and modifications of the disclosure may be used. It is also possible to provide some features of the disclosure while omitting others.

[0183] The features of the various embodiments described herein are not intended to be mutually exclusive. Rather, features and aspects of one embodiment can be combined with features or aspects of another embodiment. Furthermore, a description of a particular element relating to one embodiment may apply to the use of that particular element in another embodiment, regardless of whether the description is repeated in relation to the use of that particular element in another embodiment.

[0184] Furthermore, the descriptions in this disclosure include descriptions of one or more embodiments, configurations, or aspects, as well as specific variations and modifications, but other variations, combinations, and modifications are within the scope of this disclosure to the extent that they may be within the scope of the skills and knowledge of a person skilled in the art, for example, after understanding this disclosure. This is intended to grant rights to alternative embodiments, configurations, or aspects to the extent permitted, including alternative, interchangeable, and / or equivalent structures, functions, scopes, or steps, and there is no intention to publicly provide patentable subject matter, whether or not such alternative, interchangeable, and / or equivalent structures, functions, scopes, or steps are disclosed herein.

[0185] One aspect of this disclosure includes one or more aspects / embodiments substantially disclosed herein.

[0186] Another aspect of this disclosure is one or more aspects / embodiments substantially disclosed herein, which may be optionally combined with one or more other aspects / embodiments substantially disclosed herein.

[0187] Another aspect of this disclosure is to provide one or more means adapted to perform one or more of the aspects / embodiments substantially disclosed herein.

[0188] Aspects of this disclosure can take the form of entirely hardware embodiments, entirely software embodiments (including firmware, resident software, microcode, etc.), or embodiments combining software and hardware aspects (all of which are commonly referred to herein as “circuits,” “modules,” or “systems”). Any combination of one or more computer-readable media can be used. The computer-readable media may be computer-readable signal media or computer-readable storage media.

[0189] Computer-readable storage media may, but are not limited to, electronic, magnetic, optical, electromagnetic, infrared, or semiconductor systems, apparatus, or devices, or any suitable combination thereof. More specific examples (a non-exhaustive list) of computer-readable storage media include electrical connections with one or more wires, portable computer diskettes, hard disks, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), optical fibers, portable compact disk read-only memory (CD-ROM), optical storage devices, magnetic storage devices, or any suitable combination thereof. In the context of this document, computer-readable storage media may be any tangible medium capable of containing or storing programs used by or in connection with instruction execution systems, apparatus, or devices.

[0190] A computer-readable signal medium may include, for example, a propagated data signal in which computer-readable program code is incorporated as part of a baseband or carrier wave. Such a propagated signal may take any of a variety of forms, including but not limited to electromagnetic, optical, or any suitable combination thereof. A computer-readable signal medium is not a computer-readable storage medium, but any computer-readable medium on which a program used by or in connection with an instruction execution system, apparatus, or device can be communicated, propagated, or transferred. Program code incorporated into a computer-readable medium can be transmitted using, but not limited to, wireless, wired, fiber optic cables, RF, or any suitable combination thereof.

[0191] The terms “determine,” “calculate,” and “operate” used herein, and their variations thereof, are used interchangeably and include all kinds of methodologies, processes, mathematical operations, or techniques.

[0192] Examples of processors described here include Qualcomm® Snapdragon® 800 and 801, Qualcomm® Snapdragon® 610 and 615 with 4G LTE integration and 64-bit computing, Apple® A7 processor with 64-bit architecture, Apple® M7 motion coprocessor, Samsung® Exynos® series, Intel® Core® processor family, Intel® Xeon® processor family, Intel® Atom® processor family, Intel Itanium® processor family, Intel® Core® i5-4670K and i7-4770K 22nm Haswell, Intel® Core® i5-3570K 22nm Ivy Bridge, AMD® FX® processor family, AMD® FX-4300, FX-6300, and FX-8350 32nm Vishera, AMD® Kaveri processors, Texas Instruments® Jacinto C6000® automotive infotainment processors, Texas Instruments® OMAP® automotive-grade mobile processors, ARM® Cortex®-M processors, ARM® Cortex-A and ARM926EJ-S® processors, and other industry-equivalent processors, and known or future-developed standards, instruction sets, libraries, and / or architectures may be used to perform computational functions.

[0193] To provide additional background and context and to further satisfy the description requirements of Section 112 of the U.S. Patent Act, references in U.S. Patent No. 9,191,659, U.S. Patent No. 10,942,360, and Canadian Patent Publication No. 3,113,582 are incorporated herein by reference in their entirety. [Explanation of symbols]

[0194] The following is a list of components shown in the drawings according to various embodiments of this disclosure: Number component 2. Simulator of conventional technology 4. Main display 6. Projector 8 screens 10 Mirror Array 12. Image on the main display 14 Parallel rays 16 Objects in the image 18 downward windows 20 Real-Image Display System 22 Monitor or screen of a real-image display system 24 Images of the real-image display system 26 Simulated ground 28 Simulated height from the ground 30 users 32. Designated viewpoint 34. First arrow indicating the direction of gaze on the main display. 36. A second arrow indicating the direction of the line of sight through the lower window. 40 Simulators 42 Cockpit 44. Window on the main display 45 Top window 46. ​​Lower window 48 Main display 50 Main display projector 52 screens 54 Mirror Array 56 Image on the main display 58 Parallel rays 60 objects in the image 62 Variable aiming display system (or downward display, or variable display) 64 Image of a variable sighting display system 66 Rays of a variable sighting display system 68 Screen of a variable sighting display system 68A-1 Rear or rear projection screen 68A-2 Front projection screen 68B Self-illuminating screen 70 Screen 68 Rear 72 Screen 68 Front 74 Mirror of a variable sighting display system 76 Mirror 74 rear 78 Mirror 74 front 80 Projector with variable aiming display system 82 Adjuster for Variable Aiming Display System 84 Platforms 86 Arrows indicating platform movement 88 screen stand 90 Projector Mount 92 Actuators 94 Stop 96 Distance between mirror and screen 96A First distance 96B Second distance 98. Distance from projector to screen 100 Perceived distance: The distance between a given viewpoint and a simulated object (or the simulated distance). 102 Elevation from terrain 104 Horizontal distance to the object 106 Simulated size or height of an object 120 controllers 122 Control Systems 124 processors 126 memory 128 Communication Interfaces 130 User Interface 132 Focal Length Models 134 size model 136 Controller Instructions 138 Look-up Table 140 method Generate 142 images Determine the simulated distance to object 142. 146. Determine the focal length. 148 Determine the simulated size of the object. 150 Generate instructions to adjust 152 Adjust the simulated size of the object. 160 method 162 Receive the specified viewpoint location. Determine the simulated position of 164 objects. 166 Determine the simulated distance.

Claims

1. A system for adjusting the focal length of an image displayed to the user from a specified viewpoint, A screen that displays an image depicting an object, A mirror, located at a variable distance from the screen, reflects the image displayed by the screen to a specified viewpoint. An adjuster for moving the screen and adjusting the distance between the screen and the mirror, A system that includes this.

2. The system further includes a control system that communicates with the aforementioned regulator, The control system is The focal length of the image is determined based on the simulated distance between the specified viewpoint and the object in the image. Determining the simulated size of the object based on the simulated distance, To generate a command to the adjuster to adjust the distance between the screen and the mirror in order to achieve the focal length, Adjust the size of the object in the image based on the determined simulated size. The system according to claim 1 that causes the execution of the following:

3. The control system further generates the image. The system according to claim 2.

4. The screen is at least one of the following: a liquid crystal display, an organic light-emitting diode display, a liquid crystal display on silicon, a light-emitting diode display, a quantum dot display, and a plasma display. The system according to claim 1.

5. The system further comprises a projector that projects the aforementioned image onto the screen, The aforementioned screen is one of a front projection screen and a rear projection screen. The system according to claim 1.

6. The projector is located at a certain distance from the screen. The adjuster moves the screen and the projector. The system according to claim 5.

7. The adjuster includes a motor that moves the screen and adjusts the distance. The system according to claim 1.

8. The mirror is fixed, and the screen is interconnected to the platform of the adjuster. The platform moves to adjust the distance between the screen and the mirror. The system according to claim 7.

9. The adjuster includes a stopper to prevent the screen from coming into contact with the mirror. The system according to claim 8.

10. The distance between the screen and the mirror correlates with the focal length. In the first position, the screen is at a first distance from the mirror, and the focal length is at infinity. In the second position, the screen is at a second distance from the mirror, and the focal length is less than infinity. The first distance is longer than the second distance. The system according to claim 1.

11. At the first position, the light rays reflected from the mirror are substantially parallel. The system according to claim 10.

12. Associated with simulators that simulate aircraft, The simulator includes a downward window positioned between the designated viewpoint and the mirror, The image displayed by the screen is visible to the user through the lower window. The system according to any one of claims 1 to 11.

13. A control system for a simulator that adjusts the focal length of an image at a specified viewpoint of the simulator, Processor and The processor includes a memory that stores instructions to be executed by the processor, When the aforementioned instruction is executed, the processor: The image is reflected by a mirror and displayed on a screen that is oriented so as to pass through the lower window of the simulator and face a specified viewpoint. Determine the simulated distance from the specified viewpoint to the object in the image. Based on the simulated distance, determine the focal length of the image. Based on the simulated distance, determine the simulated size of the object. To generate a command to a adjuster that changes the distance between the screen and the mirror to achieve the focal length, Adjusting the size of the object in the image based on the determined simulated size, A control system that performs this task.

14. Determining the simulated distance is To receive the position of the specified viewpoint, To determine the simulated position of the object with respect to the specified viewpoint, Determining the distance between the designated viewpoint and the simulated position of the object, The control system according to claim 13, comprising one or more of the above.

15. The distance between the screen and the mirror correlates with the focal length. The aforementioned memory further, The processor includes an instruction to move the screen to a first position, which is a first distance from the mirror, such that the focal length becomes infinity when the simulated distance exceeds a predetermined threshold. The control system according to claim 13.

16. The aforementioned memory further, The processor includes an instruction to move the screen to a second position which is a second distance from the mirror, when the simulated distance is less than a predetermined threshold, and the focal length is less than infinity. The first distance is longer than the second distance. The control system according to claim 15.

17. The predetermined threshold is approximately 30 feet. The control system according to claim 15.

18. A method for adjusting the focal length of an image at a specified viewpoint, The aforementioned method, The process of generating an image to be displayed on a screen that is oriented so that the image is reflected by a mirror to a specified viewpoint. Determining the simulated distance between the specified viewpoint and the simulated position of the object in the image, Based on the simulated distance, determine the focal length of the image. Based on the simulated distance, determine the simulated size of the object. To generate a command to a tuner that changes the distance between the screen and the mirror to achieve the focal length, Adjusting the size of the object in the image based on the simulated size, A method that includes this.

19. When the simulated distance exceeds a predetermined threshold, the screen is moved to a first position, which is a first distance from the mirror, so that the focal length becomes infinity. When the simulated distance is shorter than a predetermined threshold, the method further includes moving the screen toward the mirror to a second position, which is a second distance from the mirror, such that the focal length becomes less than infinity. The first distance is longer than the second distance. The method according to claim 18.

20. A flight simulator for students training to pilot aircraft, A main display system that simulates the view from the window of the aforementioned aircraft, The simulator includes a variable sighting display system that simulates a second view of the outside of the aircraft as seen through a downward window located near the floor of the cabin within the cabin of the simulator, The main display system is It includes a projector, a first screen, and a mirror array. The projector is operable to generate a first image to be displayed on the first screen, The mirror array reflects the first image to a designated viewpoint of the simulator. The variable aiming display system is A second screen that displays the second image, A mirror that reflects the second image from the second screen to a specified viewpoint through the lower window, The second screen includes a regulator that moves the second screen relative to the mirror, When the second screen is at a first distance from the mirror, the second image is at infinity focus. When the second screen is at a second distance from the mirror, the second image has a fixed focal length less than infinity. The second distance is less than the first distance. Flight simulator.

21. The aforementioned mirror is at a fixed distance from the designated viewpoint. The flight simulator according to claim 20.

Images