JP2009251027A - Recurrence projection head-up display - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a lightweight, low-cost head-up display for airplane capable of reducing a pilot's visible workload. <P>SOLUTION: A recurrence reflection sheet 11 is stuck on a backside of a propeller 10 facing the pilot. A virtual instrument panel is provided, which displays an image with fusion of an actual world (pilot's sight) and an artificial image (image of the actual instrument panel in a cockpit) by projecting an image of the actual instrument panel in the cockpit from a projector onto a dynamic screen formed by rotating the propeller 10. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a recursive projection head-up display, and in particular, a recursive projection head-up display that can project an image far away with a simple and lightweight mechanism and can be mounted on a small aircraft. About.

An aircraft head display (= “Head Up Display”, hereinafter referred to as “HUD”) uses an image generated by a cathode ray tube (= “Cathode Ray Tube”, hereinafter referred to as “CRT”) by using a lens system. It is a device that combines (fuses) and displays the real world (view) and artificial video (instrument information). That is, by using the HUD, the pilot can monitor the instrument information and other flight information displayed on the HUD while monitoring the outside of the cockpit. That is, the pilot can simultaneously acquire information outside the cockpit and instrument information without changing the line of sight much. Therefore, it is known that the feature of this HUD can effectively reduce the pilot's line-of-sight movement and effectively reduce the pilot's visual workload, especially in situations where external monitoring demands are high, such as when landing. ing.
Furthermore, most aircraft HUDs can project images related to instrument information to infinity by incorporating special optical systems. As a result, it is possible to reduce the focus adjustment load on the pilot's eyeball. In other words, the pilot usually looks at an infinite distance when looking at the outside world, and the focus adjustment of the lens of the eyeball is also in focus at infinity. On the other hand, when the pilot looks at the instruments in the cockpit, these instruments are only at a distance of 1 [m] from the pilot, so the focus is about 1 [m] from the pilot. It has become. Thus, the pilot (its eyeball) is forced to adjust the focus over a wide range from infinity to 1 [m]. This focus adjustment also becomes a (visual) work load on the pilot, but by introducing the infinite HUD, it is possible to greatly reduce the load of focus adjustment on the pilot's eyeball.
In addition, in such an infinite HUD, images of the horizon and runway calculated from the instrument information are displayed. By making the projection plane of the image infinitely far away, it is possible to display the horizon / runway on the image in agreement with the actual horizon / runway without measuring the pilot's head position. It is known to bring about other effects such as improved safety when visibility is poor and improved situational awareness of pilots.
While the infinity HUD has these advantages, it is not very popular among small aircraft due to its price and weight. However, it is known that the accident rate of small aircraft is higher than that of large aircraft, and there is a high demand for an inexpensive system for improving safety targeting small aircraft. Therefore, when a flight information display system having an HUD at infinity or an equivalent function is also introduced into a small aircraft, it is expected that the accident rate and the number of accidents of the small aircraft will be significantly reduced.
By the way, in the following non-patent document 1, a simple (inexpensive) HUD for an aircraft is configured by eliminating the function of image projection to infinity. The structure is simple: a projector and a reflector. From the viewpoint of price and weight, the simple HUD is considered to be more adaptable to small aircraft than the infinite HUD.
However, this simple HUD uses a brown glass plate to fuse the projector image (artificial image) with the real field of view. It is thought that. This is a few tens [cm] to 1 [m] at most from the pilot point of view, and the load of focus adjustment (distant / near focus by lens adjustment) on the pilot is the conventional instrument display (instrument inside the cockpit) And not so much.
On the other hand, a recursive projection technology (= “Retro-reflective Projection Technology”, hereinafter referred to as “RPT”) is known as a method for fusing the real world and video rendered by a computer. This RPT can see a homogeneous image without distortion regardless of the shape of the object by assembling a coaxial optical system using a projector for a screen made of a material having a retroreflective function. Is. In addition, a so-called optical camouflage technique has been proposed that projects an image of the real world onto a screen of a retroreflective material as if the object became transparent (for example, Patent Document 1 and Non-Patent Document 1). (See Patent Documents 2 to 4).
FIG. 6 is an explanatory diagram showing a configuration of an optical camouflage technique to which this RPT is applied. In this RPT, an observer's eyes and a projector form a coaxial optical system via a half mirror. Then, when projecting a “background image” (rectangular image) from the projector, the background image is projected onto the retroreflecting material via the half mirror, which returns to the eyes of the observer. . At this time, the image of the background is projected on the retroreflecting material, and the image is displayed uniformly without distortion, regardless of the shape of the object, so the observer can almost see the shield. A transparent state (pseudo-transparent state) that cannot be performed is realized. However, the retroreflecting material itself is a material that reflects light and is not physically transparent. If the background changes dynamically, a camera or the like is required to acquire the background image. In other words, when using this optical camouflage technology applying RPT in a situation where the background changes dynamically, a separate camera for reflecting the background behind the shield called a retroreflective material is prepared separately, and the image is displayed. There is no choice but to send it to the projector (converted into an electrical signal). By using this RPT, it is possible to simultaneously display a real-world image and artificial instrument information (drawn by a computer). However, it is a problem that a camera is required for this purpose. This is because, at the current technical level, the camera has a narrow dynamic range with respect to brightness, and cannot be used from daytime to nighttime. In addition, since a camera generally has a viewing angle that is not so wide, it is difficult to obtain an image with sufficient resolution to compensate for the pilot's viewing angle with a single camera. These problems can be technically solved by using multiple cameras together. In this case, however, there are problems such as an increase in weight, an increase in price, and an increase in failure probability due to an increase in system components. For some reason, the present invention is not a solution to the problem to be solved. For this reason, it is considered difficult to use optical camouflage technology consisting of a camera and RPT on an aircraft as an aircraft instrument display for pilots.

JP 2000-10194 A Enhanced Head-UP Display for General Aviation aircraft, Burch, D.P.; Braasch, M.S.Digital Avionics Systems Conference, 2002.Proceedings.The 21st Volume 2, Issue, 2002 Page (s): 11C6-1-11C6-11 Inami, Kawakami, Yanagida, Maeda, Satoshi: "Study on Fusion of Reality (1st Report) -Proposal and Experimental Implementation of Seamless Reality Fusion Method", Proceedings of the 3rd Annual Conference of the Virtual Reality Society of Japan, pp. 281-284,1998. Yoshida, Shiro, Minamizawa, Arai, Kawakami, Satoshi: "Presentation of out-of-view information on vehicles using recursive projection technology", Proceedings of the 12th Annual Conference of the Virtual Reality Society of Japan, pp.161-162, 2007. Saito, Yanagida: "Examination of the possibility of see-through pillars using recursive projection technique", Proceedings of the 12th Annual Conference of the Virtual Reality Society of Japan, pp.163-164, 2007.

As described above, it is known that by using the HUD in an aircraft, it is possible to reduce the amount of movement of the pilot's line of sight and contribute to reducing the pilot's workload. It is also known that using an infinite HUD has another effect of reducing the focus adjustment load.
However, a complex optical system is required to make the HUD an infinite image, and there are problems of increasing weight and price. Therefore, the spread of small aircraft has been delayed despite the higher accident rate than large aircraft.
Further, the simple HUD configured by the projector and the brown glass (half mirror) exemplified in Non-Patent Document 1 has a simple configuration, and can be mounted on a small aircraft from the viewpoint of price and weight. It is sufficiently possible to reduce the amount of line-of-sight movement related to outside monitoring through the cockpit window and acquisition of instrument information.
However, since the projection plane of the image is the same distance as the instruments mounted inside the conventional cockpit, the focus adjustment load on the pilot's eyes is unchanged compared to the conventional maneuver without using the HUD it is conceivable that.
In addition, recursive projection technology (RPT) is a means for merging and displaying real-world vision and artificial video information.
However, a non-transparent retroreflective material is required as a screen, and this is not transparent (shields the field of view) .For example, a retroreflective material is pasted on the cockpit window to replace the display. Use in is extremely difficult.
Accordingly, the present invention has been made in view of the problems of the prior art, and the object thereof is light and inexpensive, and can project an image far away with a simple mechanism and can be mounted on a small aircraft. It is an object of the present invention to provide a recursive projection head-up display that enables the above.

In order to achieve the above object, in the retroprojection head-up display according to claim 1, a desired image is projected on a screen provided with a retroreflective material, and the image is superimposed on an observer's field of view. A recursive projection head-up display for displaying,
The screen is dynamically formed by rotating one or a plurality of rotating blades arranged with a gap in the circumferential direction of the rotating shaft and attached with a retroreflecting material, and the background is transmitted through the image. A projected image is displayed.
In the recursive projection head-up display, a rotating blade with a retroreflecting material rotates at a high speed to form a dynamic screen that does not shield the front view (background), that is, transmits the background. Is possible. Therefore, by projecting desired image information on the dynamic screen with a projector such as a projector, the viewer's field of view has real-world images and artificial images without blocking the front field of view. It is possible to construct a so-called virtual display that displays the fused video. Furthermore, by placing the rotating blade (dynamic screen) as far as possible from the observer's steady line of sight, it is possible to reduce the load of the observer's focus adjustment. Therefore, this recursive projection head-up display is used to display flight information in work situations where the visual load is frequently adjusted and the resulting visual load is very high, such as when the pilot is operating the aircraft. By introducing it into a small aircraft as a device, the pilot can reduce the amount of eye movement and reduce the load of focusing, and can display both real-world images (background) and artificial images (instrument information). It can be acquired. Further, as will be described later, this recursive projection head-up display has a very simple configuration, and thus can be reduced in cost without substantially increasing the weight. Therefore, by installing this recursive projection head-up display on a small aircraft as a flight information display device, it is expected that the pilot's visual load will be greatly reduced. As a result, it contributes to a reduction in the accident rate of small aircraft. It is expected.

The retroprojection head-up display according to claim 2, wherein a propeller is used as the rotary blade, a retroreflecting material is attached to a surface facing the pilot of the propeller, and the propeller is rotated to thereby change the dynamic screen. Projecting information on the dynamic screen that the pilot such as measurement / navigation should always watch and monitor as a projected image, and display a projected image with a transparent background on the image; did.
In the recursive projection head-up display, the target is first limited to the single propeller aircraft. Then, a retroreflecting material is attached to the back of the propeller. By doing so, the retroreflective material moves at high speed during the flight, so that it cannot be seen with the naked eye. Then, by projecting an image there (on a dynamic screen), artificial image information can be projected. As a result, it is possible to merge and display the visual field (video) in the real world and artificial video information. The propeller has a curved shape, and its angle changes during flight. In the case of image projection by a simple projector, there arises a problem that the image is distorted due to the shape and angle of the propeller and a difference in brightness occurs. However, when the recursive projection head-up display is used, such a problem does not occur, and it is possible to display a homogeneous image independent of the state of the propeller.
Information other than cockpit instrument / operation information that the pilot must always watch and monitor includes, for example, information related to weather and meteorological conditions such as turbulence. It is possible to display it by fusing it to the video.

  Note that the display using the retroreflecting material shown in FIG. 6 realizes the same function as that of the present invention by the configuration of the shielding object provided with the retroreflecting material, the projector, the camera, and the half mirror. That is, both are common in that the technique uses a retroreflecting material. However, the two differ greatly in the optical characteristics of the image projection surface provided with the retroreflective material and the effects it brings. That is, in the case of the display using the retroreflecting material shown in FIG. 6, the image projection surface is not optically transparent, and the observer uses the real world (background) behind the image projection surface (the other side) as the image projection surface. It is impossible to see directly through. Therefore, the observer must look indirectly using a camera that projects the background, whereas in the case of the present invention, the image projection surface is optically transparent, so the observer does not use the camera. But you can see the other side of the image projection surface directly. That is, the present invention can exhibit the same function as the display using the retroreflecting material of FIG. 6 without using a camera. As a result, the present invention has significant advantages in terms of weight and price (cost) associated with the camera compared to the display of FIG.

  By the way, by using a projector and a half mirror (translucent plate), that is, by using the half mirror as an image projection surface, the observer can directly see the projected image and the real world on the other side as in the present invention. Will be able to. However, since the installation location of the half mirror, which is the image projection plane, is limited to the vicinity of the cockpit, the pilot focus adjustment load is not much different from that when viewing the instrument panel of a conventional cockpit. The present invention, on the other hand, can project an image farther than a display using this half mirror, and as a result, the pilot focus adjustment load can be further reduced. For example, in a general single propeller aircraft, the distance between the pilot and the propeller is about 2 [m], which is longer than the distance to the instrument inside the cockpit. Therefore, the image projection surface according to the present invention is a cockpit. Located far from the internal instrument. Further, as will be described later, the configuration of the present invention is mainly configured by a projector, a retroreflecting material, and a coaxial optical system, and thus is a configuration that is lighter and less expensive than a conventional head-up display. In this respect as well, the applicability to small aircraft is considered high.

4. The retroprojection head-up display according to claim 3, wherein when a color wheel type projector is used as a video projection unit for projecting a desired image on a screen provided with the retroreflective material, the color wheel is used. And the rotation of the rotating blade / propeller are synchronized.
In the recursive projection head-up display, a dynamic screen is formed by rotating a rotating blade at a high speed. In other words, the rotary blade, which is the image display position, is in a different position at each moment of each cycle. Therefore, in the case of a single-plate projector that controls the timing of projecting light such as red, green, and blue by the rotation of the color wheel, if the rotation of the color wheel and the rotation of the rotating blades are not synchronized, There may be a case where the projected color is not displayed. As a result, so-called color separation occurs in which the color of the image projected on the dynamic screen fluctuates with the rotation of the rotating blades. Therefore, in the present invention, when the color wheel system is used as the projector, the color wheel rotation and the rotation of the rotating blades are synchronized so that the image is projected on the dynamic screen so that color separation does not occur. To.

  The present invention is a technology that makes it possible to construct a head-up display at a low cost and at a low cost without using a special optical system, and to project an image far away with a simple mechanism. As a result, the possibility of mounting a head-up display on a single propeller aircraft (small aircraft) is expected to increase. By mounting the recursive projection head-up display according to the present invention on a small aircraft, the pilot visual work load can be reduced and the small aircraft from the viewpoint of reducing the amount of movement of the pilot's line of sight and reducing the focus adjustment load on the pilot's eyes. This is considered to contribute to the improvement of safety.

  Hereinafter, the present invention will be described in more detail with reference to embodiments shown in the drawings.

FIG. 1 is an explanatory view showing an embodiment in which the recursive projection head-up display 100 of the present invention is applied to a small aircraft.
The retroreflective projection display 100 uses a propeller 10 to form a dynamic screen that displays a projected image, for example, a virtual instrument panel, that fuses the real world with an artificial image. A retroreflective sheet (retroreflective material) 11 is attached or applied in advance to the back surface of the propeller 10, that is, the outer surface facing the pilot. As the retroreflective sheet 11, for example, a retroreflective sheet manufactured by Leflight or a retroreflective sheet manufactured by 3M (Scotchlite 680-85, black) can be used. The retroreflective sheet was cut into a propeller shape and attached so as to cover almost the entire back side of the propeller. In the propeller 10 in FIG. 1, the white area is the area where the retroreflective sheet is pasted. In this example, the retroreflective sheet 11 was attached to all three propellers (blades) in consideration of the weight balance between the propellers. Then, an image of the actual instrument panel inside the cockpit is projected onto a transparent dynamic screen formed by rotating the propeller 10 using a projector (not shown). As the projector, for example, a BenQ projector (MP770, 3200 [lm]) or an Epson liquid crystal projector (EMP-1810) can be used. The projector can be installed from the viewpoint of a simple configuration, for example, in the vicinity of the head support portion of the seat or on the pilot's head via a headband. Alternatively, as shown in FIG. 6, the pilot and the projector can form a coaxial optical system via a half mirror.

  Further, when a color wheel type (single plate) type projector is used as the projector, it is necessary to synchronize the rotation of the propeller 10 and the rotation of the color wheel. If these two rotations are not synchronized, so-called color separation occurs in which the color of the image projected on the dynamic screen fluctuates with the rotation of the propeller 10. However, when using a three-plate (3LCD) projector that does not use a color wheel, color separation does not occur in principle, so a clear image can be obtained without using a special additional system (synchronizer). You can get it. From the viewpoint of simplification of the entire system, it is more preferable to use a projector that does not use a color wheel, for example, a three-plate (3LCD) projector.

FIG. 2 is an explanatory diagram showing a state in which an instrument image is projected on a dynamic screen (rotating propeller). FIG. 2A shows an image of the actual instrument panel of the cockpit to be projected, and FIG. 2B shows a state in which the image is projected on the dynamic screen.
From this figure, it can be seen that the projected image of the actual cockpit instrument panel is displayed on the dynamic screen superimposed on the pilot's field of view without blocking the pilot's field of view. That is, by projecting an image of the cockpit actual instrument panel onto a dynamic screen (rotating propeller) with the retroreflective sheet 11 attached thereto, an artificial image (image of the actual instrument panel) in the real world (pilot's field of view). ) Can be built into a virtual instrument panel. Moreover, the position (place) where this virtual instrument panel is displayed (constructed) is a propeller farther from the cockpit. Therefore, the amount of focus adjustment when the pilot switches the field of view from the real world to the virtual instrument panel is much smaller than the amount of focus adjustment when the pilot switches the field of view from the real world to the real instrument panel. Similarly, the amount of line-of-sight movement when the pilot switches the field of view from the real world to the virtual instrument panel is also much smaller. Accordingly, the recursive projection head-up display 100 of the present invention is expected to significantly reduce the pilot's visual workload. In addition, since it is constituted by the retroprojection head-up display 100, mainly the propeller 10, the retroreflective sheet 11, and the projector, it is extremely light and inexpensive as compared with the conventional head-up display.

FIG. 3 is an explanatory diagram showing a state in which another image is projected on the dynamic screen as a reference. FIG. 3A shows a projected image, and FIG. 3B shows a state in which the image is projected on a dynamic screen.
From this figure, it can be seen that for images other than the actual instrument panel of the cockpit, an image in which the real world and the artificial image are fused can be displayed on the dynamic screen without blocking the pilot's view. Therefore, for example, it is possible to display character information or map information relating to turbulence, low atmospheric pressure, etc. that hinders safe operation of the aircraft on this dynamic screen.

  The retroreflective head-up display 100 is an aircraft virtual instrument panel that fuses and displays the real world (pilot field of view) and artificial images (instrument information) to reduce the pilot's visual workload. As an example. As another embodiment of the present invention, it can also be used as a simple video display such as a movie or a game machine. That is, as shown in FIG. 4, a retroreflective sheet 11 is attached to a fan 12 of a fan, the fan 12 is rotated to form a dynamic screen, and an image is projected onto the dynamic screen by a projector. Thus, the recursive projection head-up display of the present invention functions as a simple video display. FIG. 5 shows a state in which an image is projected on the rotating fan. The projected images are the same as FIG. 2 for FIG. 5A and FIG. 3 for FIG. 5B.

  As described above, the retroreflective head-up display of the present invention can construct a head-up display at a low cost and at a low cost without requiring a special optical system, and can project an image far away with a simple mechanism. Technology. As a result, the possibility of mounting a head-up display on a single propeller aircraft (small aircraft) is expected to increase. Therefore, by mounting the recursive projection head-up display of the present invention on a small aircraft, the pilot's visual workload is reduced and the safety of the small aircraft is reduced from the viewpoint of reducing the pilot's line-of-sight movement and the focus adjustment amount. It is thought that it contributes to improvement.

That is, the present invention is (1) a lightweight and inexpensive head-up display configuration method considering the possibility of mounting on a small machine,
(2) A method of projecting images far away with a simple mechanism, regardless of image projection to infinity, and
(3) In the recursive projection technology, by providing a technique for displaying real world images and artificial images without using a camera, the pilot's visual workload can be reduced and small aircraft It contributes to safety improvement.

  The recursive projection head-up display of the present invention can be applied to aircraft flight information display devices, video display devices for AV equipment, or simulation technology.

It is explanatory drawing which shows the Example which applied the recursive projection head-up display of this invention to the small aircraft. It is explanatory drawing which shows the state which projected the instrument image | video on the dynamic screen (rotating propeller). It is explanatory drawing which shows the state which projected the other image on the dynamic screen for reference. It is explanatory drawing which shows the Example which applied the recursive projection head-up display of this invention to the video display apparatus of AV apparatus. It is explanatory drawing which shows the state which projected the image | video on the dynamic screen (rotary fan). It is explanatory drawing which shows the projection technique using the conventional retroreflection material.

Explanation of symbols

10 Propeller (dynamic screen)
11 Retroreflective sheet 12 Fan 100 Retrospective projection head-up display

Claims (3)

A recursive projection head-up display that projects a desired image on a screen provided with a retroreflective material and displays the image superimposed on an observer's field of view,
The screen is dynamically formed by rotating one or a plurality of rotating blades arranged with a gap in the circumferential direction of the rotating shaft and attached with a retroreflecting material, and the background is transmitted through the image. A recursive projection head-up display characterized by displaying a projected image.   A propeller is used as the rotating blade, a retroreflecting material is attached to the surface facing the pilot of the propeller, and a dynamic screen is formed by rotating the propeller, and a projected image such as measurement / navigation The recursive projection head-up display according to claim 1, wherein information that a pilot must always watch and monitor is projected on the dynamic screen, and a projected image with a background transmitted through the image is displayed.   When a color wheel type projector is used as the image projection means for projecting a desired image on the screen with the retroreflective material, the rotation of the color wheel and the rotation of the rotary blade / propeller are synchronized. The recursive projection head-up display according to claim 1 or 2.