JPWO2018199246A1 - Virtual image display device and display system for moving object - Google Patents

Abstract

Provided is a virtual image display device which has a simple configuration and can superimpose and display additional information such as a danger signal on an object to the extent that appropriate recognition is possible. A virtual image display apparatus 100 including an image forming element 11 that is a drawing device, a main body optical system 13 that is an enlarged projection optical system that enlarges an image of the image forming element 11, and a display screen 20, wherein the image forming element 11 is A plurality of display images (virtual images) IM having different projection distances are displayed by linking the arrangement changing device 62 that changes the projection distance by moving in the optical axis AX direction with the image forming element 11 and the arrangement changing device 62. A display control unit 18.

Description

  The present invention relates to a virtual image display device that displays a virtual image ahead of a line of sight, and a display system for a moving object equipped with the virtual image display device.

  2. Description of the Related Art Conventional head-up display (HUD) devices generally generate a virtual image at a position separated from a driver by a certain distance, and the display contents by the HUD include vehicle speed and car navigation. Information was limited. In the first place, the purpose of mounting a HUD on a car is to support safer driving by minimizing the driver's line of sight movement. However, in terms of safe driving support, it is not enough to display information such as vehicle speed alone. Insufficient, for example, a system that detects a car, a pedestrian, an obstacle, or the like in front of the vehicle with a camera or a sensor, and makes the driver sense the danger in advance through the HUD to prevent an accident is more preferable. . To realize such a system, for example, a danger signal or other additional information may be superimposed and displayed on a see-through image (object) such as a car, a person, and an obstacle.

  In a system in which the danger signal is superimposed and displayed as described above, if the distance from the driver to the virtual image is constant, the position of the real object (object) and the danger signal (virtual image) are changed when the driver's eye position is shifted. ) Is deviated from the position, and the driver may erroneously recognize the danger signal (that is, erroneously recognize the position of the object). As a method of solving such a problem, it is conceivable to superimpose a virtual image on a real object (object) including the depth direction.

  For example, Patent Document 1 discloses a method of changing the position of a virtual image by using a scanning image forming unit such as a MEMS (Micro Electro Mechanical Systems) mirror, a screen, a projection unit, and a movable unit that changes the position of the screen. It has been disclosed. However, the main purpose of Patent Literature 1 is to reduce the driver's line of sight by moving the virtual image position closer or farther in accordance with the speed of the vehicle, and display the danger signal and the target object in a superimposed manner. It is not intended. Further, the technique described in Patent Literature 1 does not presuppose the above-described superimposed display, and thus does not relate to the positional displacement between the danger signal and the object.

JP 2009-150947 A

  The present invention has been made in view of the above background art, and has a simple configuration, but a virtual image display device capable of superimposing and displaying the above additional information on an object to such an extent that appropriate recognition is possible. The purpose is to provide.

  Further, another object of the present invention is to provide a display system for a moving object equipped with the virtual image display device.

  In order to achieve at least one of the above-described objects, a virtual image display device according to an aspect of the present invention includes a drawing device, a virtual projection optical system that enlarges an image of the drawing device, and a virtual image including a display screen. A display device, wherein a layout changing device that changes a projection distance by moving a drawing device in an optical axis direction and a display that displays a plurality of virtual images having different projection distances by linking the drawing device and the layout changing device. A control unit. Here, the optical axis passes through the center of the drawing device, the center of the eye box, and an image point (virtual image) corresponding to the center of the drawing device created by the virtual image display device.

  In order to achieve at least one of the above-described objects, a display system for a mobile object that reflects one aspect of the present invention includes the above-described virtual image display device and an environment monitoring unit that detects a spatial position of an object. , Is provided.

FIG. 1A is a side cross-sectional view illustrating a state where the virtual image display device of the embodiment is mounted on a vehicle body, and FIG. 1B is a front view illustrating the virtual image display device from the inside of the vehicle. FIG. 2 is a diagram illustrating a specific optical system constituting the virtual image display device. It is a conceptual expanded side sectional view explaining the example of a specific structure of a virtual image display device. FIG. 3 is a diagram for explaining a relationship between a position of an image forming element and a virtual image position, and the like. 5A and 5B are diagrams illustrating the positional relationship between a virtual image position and an object by the virtual image display device according to the embodiment. 6A and 6B are diagrams illustrating the positional relationship between a virtual image position and an object by the virtual image display device of the comparative example. It is a block diagram explaining the display system for mobile bodies containing a virtual image display device. It is a flowchart explaining operation | movement of the display system for mobile bodies.

  Hereinafter, an embodiment of a display system for a virtual image display device moving object according to the present invention will be described with reference to the drawings.

  1A and 1B are a schematic side sectional view and a front view illustrating a virtual image display device 100 of the present embodiment and a use state thereof. The virtual image display device 100 is mounted in the vehicle body 2 as a head-up display device, for example, and includes a drawing unit 10 and a display screen 20. The virtual image display device 100 displays image information displayed on an image forming element 11 described later in the drawing unit 10 to a driver (observer) UN via a display screen 20 as a virtual image.

  The drawing unit 10 of the virtual image display device 100 is installed so as to be embedded in the dashboard 4 of the vehicle body 2, and directs the display light HK corresponding to an image including driving-related information and a danger signal to the display screen 20. Inject. The display screen 20 is a half mirror, also called a combiner, and is a semi-transparent concave mirror or a plane mirror. The display screen 20 is erected on the dashboard 4 by supporting the lower end, and reflects the display light HK from the drawing unit 10 toward the rear of the vehicle body 2. That is, in the illustrated case, the display screen 20 is an independent type that is installed separately from the windshield (windshield) 8. The display light HK reflected by the display screen 20, which is a half mirror, is guided to an eye box (not shown) corresponding to the pupil HT of the driver UN sitting in the driver's seat 6 and its peripheral position. As shown in FIGS. 1A and 2, the driver UN can observe the display light HK reflected on the display screen 20, that is, the display image IM as a virtual image in front of the vehicle body 2. On the other hand, the driver UN can observe the external light transmitted through the display screen 20 which is a half mirror, that is, the front view, the real image of the automobile, and the like. As a result, the driver UN superimposes a display image (virtual image) IM including driving-related information, a danger signal, and the like formed by reflection of the display light HK on the display screen 20 over the external image behind the display screen 20. Can be observed.

  As shown in FIG. 3, the drawing unit 10 includes a main body optical system 13, a display control unit 18 that operates the main body optical system 13, and a housing 14 that houses the main body optical system 13 and the like. Of these, a combination of the main body optical system 13 and the display screen (combiner) 20 constitutes a virtual image display optical system 30. In FIG. 3 and the like, the coordinate axes XYZ have the origin at the center of the eye box corresponding to the position between the pupils HT of the general driver UN, but are displayed with the origin shifted for convenience.

  The main body optical system (projection optical system) 13 includes the image forming element 11 and a virtual image forming optical system 17 that converts an image formed on the image forming element 11 into a virtual image.

  The image forming element 11 is a drawing device (display unit) having a two-dimensional display surface 11a. The image formed on the display surface 11a of the image forming element 11 is guided to the virtual image forming optical system 17 and the like. At this time, by using the image forming element 11 capable of two-dimensional display, switching of the display image (virtual image) IM can be made relatively fast. The image forming element 11 includes a liquid crystal display panel (or a liquid crystal display (LCD)), a display driving circuit for causing the liquid crystal display panel to perform a display operation, and an LED (light emitting light) for illuminating the liquid crystal display panel. light emitting diode) and other light sources, a uniforming optical system for equalizing light from the light sources, and the like. By using a liquid crystal display as a drawing device, the size of the device can be reduced. Further, since the light distribution angle of the LCD is wide, the viewing angle can be widened. The image forming element 11 operates at a frame rate of, for example, 60 fps or more, preferably 240 fps, and more preferably 1000 fps. This makes it easy to make it appear that a plurality of display images IM are displayed simultaneously at different projection distances.

  The image forming element 11 is driven by the arrangement changing device 62 and moves along the optical axis AX at a constant speed or a periodic motion, for example. By moving the image forming element 11 along the optical axis AX by the arrangement changing device 62, the observer is a display image IM as a virtual image formed behind the display screen (combiner) 20 by the virtual image forming optical system 17 and an observer. The distance to the driver UN can be made longer or shorter. In this way, by changing the position of the projected display image IM back and forth, and by making the display content correspond to the position, the display image IM can be changed while changing the virtual image distance or the projection distance to the display image IM. Is changed, and the display image IM as a series of projection images can be made three-dimensional. Here, the optical axis AX is defined as an image point corresponding to the center of the image forming element 11 which is a drawing device, the center of the eye box, and the center of the image forming element (drawing device) 11 formed by the virtual image display device 100. Virtual image). The amount of movement of the image forming element 11 in the direction of the optical axis AX is 20 mm or less. Accordingly, the image forming element 11 can be moved efficiently, the responsiveness of the image forming element 11 can be improved, and the volume of the virtual image display device 100 can be reduced. The arrangement changing device 62 reciprocates the image forming element 11 at a speed of, for example, 15 Hz or more. In this case, since the speed exceeds the perception of the observer (driver UN), the observer can recognize virtual images having different projection distances substantially simultaneously.

  The image forming element 11 is supported by a support member 62a. The support member 62a is movably attached to a pedestal 62b of the arrangement changing device 62 within a predetermined range along the optical axis AX direction. As shown in FIG. 4, at the timing when the image forming element 11 is arranged at the most upstream side of the movement range, the image displayed on the image forming element 11 at this time is displayed on a display screen (combiner) 20 which is a half mirror. Is displayed as a virtual image farthest behind. Also, at the timing when the image forming element 11 is arranged at the most downstream side of the movement range, the image displayed on the image forming element 11 at this time is closest to the rear of the display screen (combiner) 20 which is a half mirror. Is displayed as a virtual image. In the example of FIG. 4, the position (LCD position T1) of the image forming element 11 at the timing when the image forming element 11 is arranged on the most upstream side of the movement range is along the optical axis AX direction when the virtual image distance is 10 m. This is a position having a distance of 8.1 mm in a direction relatively moving away from a first mirror 17a described later. When the image forming element 11 is located at the most downstream side of the movement range, the position (LCD position T2) of the image forming element 11 is the first position along the optical axis AX direction when the virtual image distance is 3.5 m. This is a position having a distance of 7.7 mm in a direction relatively approaching the mirror 17a. An LCD position T3 intermediate the LCD positions T1 and T2 has a virtual image distance of 5 m.

  The virtual image forming optical system 17 is an enlarged projection optical system that enlarges an image formed on the image forming element 11 in cooperation with the display screen 20, and forms a display image IM as a virtual image in front of the driver UN. The virtual image forming optical system 17 includes at least one mirror. In the illustrated example, the virtual image forming optical system 17 includes two first and second mirrors 17a and 17b. Here, the first mirror 17a is a first reflector, and is arranged on the image forming element 11 side in a stage before the optical path, and has an optical power. Further, the second mirror 17b is arranged on the display screen (combiner) 20 side at the latter stage of the optical path, and has an optical power. The first and second mirrors 17a and 17b can be convex, concave, or flat. In the case of a curved surface, the mirror is not limited to a spherical surface, but can be an aspheric surface, a free-form surface, or the like.

  The housing 14 has an opening 14a through which the display light HK passes, and a light transmitting member 14b in the form of a film or a thin plate can be disposed in the opening 14a.

  FIG. 5A is a conceptual plan view illustrating display by the virtual image display optical system 30 or the virtual image display device 100 according to the embodiment, and FIG. 5B is a diagram illustrating how the display corresponding to FIG. 5A is viewed. As shown in FIG. 5A, a case will be described in which a display frame HW, which is a display image IM, is formed at or near the position of an object (in this case, an automobile traveling in the oncoming lane) KT observed by the driver UN. . Such a display frame HW is a danger warning signal or other virtual image, and indicates, for example, a result of identifying a car, a bicycle, a pedestrian, and the like approaching ahead. In this case, the display frame HW projects the display frame HW near the target object KT as shown in FIG. 5A. Therefore, as shown in FIG. 5B, not only the driver UN at the standard position P0 but also the head UN The target object KT and the display frame HW are almost overlapped with each other and can be seen by the driver UN whose posture has been changed to the fluctuation position P1 in which the position of the target frame KT is moved.

  FIG. 6A is a conceptual plan view illustrating display by a virtual image display optical system or a virtual image display device of a comparative example, and FIG. 6B is a diagram illustrating how the display corresponding to FIG. 6A looks. As shown in FIG. 6A, a case will be described in which a display frame HW, which is a display image IM, is formed at a fixed position regardless of the target object KT observed by the driver UN. In this case, the display frame HW is projected far in front of the target object KT as shown in FIG. 6A. Therefore, as shown in FIG. 6B, for the driver UN at the standard position P0, the target object KT and the display frame HW are displayed. And the driver UN changes the posture to the change position P1, the display frame HW appears to be greatly displaced in the horizontal direction in which the eyes are aligned with the object KT. , The possibility of misidentifying the display frame HW is increased.

  FIG. 7 is a block diagram illustrating the display system 200 for a mobile object. The display system 200 for a mobile object includes the virtual image display device 100 as a part thereof. The virtual image display device 100 has the structure shown in FIG. 3, and the description is omitted here. The moving object display system 200 shown in FIG. 7 is incorporated in a moving object such as an automobile.

  The mobile display system 200 includes a driver detection unit 71, an environment monitoring unit 72, and a main control device 90 in addition to the virtual image display device 100.

  The driver detection unit 71 is a unit that detects the presence or the viewpoint position of the driver UN, and includes a driver seat camera 71a, a driver seat image processing unit 71b, and a driver seat image determination unit 71c. The driver's seat camera 71a is installed in front of the driver's seat of the dashboard 4 in the vehicle body 2 (see FIG. 1B), and captures images of the head of the driver UN and its surroundings. The driver's seat image processing unit 71b performs various image processing such as brightness correction on an image captured by the driver's seat camera 71a, and facilitates the processing by the driver's seat image determination unit 71c. The driver's seat image determination unit 71c detects the head and eyes of the driver UN by extracting or cutting out an object from the driver's seat image that has passed through the driver's seat image processing unit 71b, and is attached to the driver's seat image. From the depth information, the presence or absence of the head of the driver UN in the vehicle body 2 and the spatial position of the eyes of the driver UN are calculated.

  The environment monitoring unit 72 is a unit that identifies an automobile, a bicycle, a pedestrian, and the like approaching forward, and includes an external camera 72a, an external image processing unit 72b, and an external image determination unit 72c. The external camera 72a is installed at an appropriate position inside or outside the vehicle body 2, and captures an external image of the driver UN or the front or side of the windshield 8 or the like. The external image processing unit 72b performs various types of image processing such as brightness correction on an image captured by the external camera 72a to facilitate the processing by the external image determination unit 72c. The external image determining unit 72c detects the presence or absence of a target KT (for example, see FIG. 5A) such as a car, a bicycle, and a pedestrian by extracting or cutting out the target from the external image that has passed through the external image processing unit 72b. At the same time, the spatial position of the target object KT in front of the vehicle body 2 is calculated from the depth information attached to the external image. Here, the spatial position of the target object KT includes not only the position in the plane corresponding to the visual field but also the position in the depth direction.

  Although not shown, the driver's seat camera 71a and the external camera 72a are, for example, compound eye type three-dimensional cameras. In other words, both cameras 71a and 72a are arranged in a matrix with camera elements each having a pair of an imaging lens and a CMOS (Complementary Metal Oxide Semiconductor) or other image sensor. Each has a circuit. The plurality of camera elements constituting each of the cameras 71a and 72a are adapted to focus on, for example, different positions in the depth direction, or to detect relative parallax, and are obtained from each camera element. By analyzing the state of the image (the focus state, the position of the object, and the like), the distance to each region or the object in the image can be determined.

  Even if a two-dimensional camera and an infrared distance sensor are combined or a laser sensor is used instead of the compound-eye cameras 71a and 72a as described above, the depth direction of each part in a captured screen (blind spot image) Distance information can be obtained. Further, instead of the compound-eye cameras 71a and 72a, a stereo camera in which two two-dimensional cameras are separately disposed can obtain distance information in the depth direction with respect to each part (region or object) in the captured screen. In addition, distance information in the depth direction can be obtained for each part in the captured screen by performing imaging while changing the focal length at a high speed with a single two-dimensional camera.

  The display control unit 18 operates the virtual image display optical system 30 under the control of the main control device 90 to provide a three-dimensional display in which the virtual image distance or the projection distance changes behind the display screen (combiner) 20 which is a half mirror. The image IM is displayed. That is, the display control unit 18 displays a plurality of display images (virtual images) IM by linking the image forming element 11 and the arrangement changing device 62. The display control unit 18 generates a display image IM to be displayed on the virtual image display optical system 30 from the display information including the display shape, the display distance, or the position information received from the environment monitoring unit 72 via the main control device 90. The display image IM is, for example, a display frame HW (FIG. 5B) that is located around the car, bicycle, pedestrian, and other objects KT present behind the display screen 20 in the depth direction and the direction orthogonal thereto. (See References). The display control unit 18 receives the position information of the target object KT from the environment monitoring unit 72 and displays a display image (virtual image) IM according to the position of the target object KT corresponding to the display screen 20 in the screen. This allows the position of the display image (virtual image) IM to correspond to the position of the target object KT, regardless of the viewpoint of the driver UN. Further, under the control of the main controller 90, the display control unit 18 receives the position information of the target KT from the environment monitoring unit 72, and adjusts the projection distance in accordance with the spatial position of the target KT. . Thereby, even if the viewpoint of the driver UN shifts, it is possible to prevent the position of the display image (virtual image) IM from shifting from the position of the target KT that changes. Further, the display control unit 18 causes the image forming element 11 to display an image in synchronization with the movement of the image forming element 11 by the arrangement changing device 62. Accordingly, the display content of each virtual image having a different projection distance can be changed, and an image corresponding to the target KT which may be present at each position can be displayed.

  The display control unit 18 receives a detection output regarding the presence of the driver UN and the position of the eyes from the driver detection unit 71 via the main control device 90. Thereby, it becomes possible to automatically start and stop the projection of the display image IM by the virtual image display optical system 30. Further, it is also possible to perform a projection in which only the display image IM is brightened or blinked in accordance with the spatial position of the eyes of the driver UN.

  The main control device 90 has a role of harmonizing the operations of the virtual image display device 100, the environment monitoring unit 72, and the like, and virtual image display optics so as to correspond to the spatial position of the target object KT detected by the environment monitoring unit 72. The spatial arrangement of the display frame HW projected by the system 30 is adjusted.

  Hereinafter, the operations of the virtual image display device and the display system for a moving object will be described with reference to FIG. The operation of the display control unit 18, the arrangement change device 62, and the like is started by receiving, for example, a detection output related to the position of the eyes of the driver UN from the driver detection unit 71.

  First, the virtual image display device 100 is initialized (step S11). Specifically, under the control of the main controller 90, the arrangement changing device 62 is operated to move the position of the image forming element 11 to the initial position. As described above, the image forming element 11 is movable in a predetermined range along the optical axis AX direction. For example, in the range from the most downstream side to the most upstream side in the moving range, for example, the most upstream side The position is the initial position. In addition, the timing at which an image is displayed on the image forming element 11 in a fixed cycle based on the initial position and the operation timing of the arrangement changing device 62 are synchronized.

  Next, the object KT is searched (step S12). Specifically, under the control of the main controller 90, the environment monitor 72 is operated to detect the presence or absence of the target KT.

  Next, the target object KT in the display area (or screen) of the display screen 20 is detected (Step S13). Specifically, the environment monitor 72 is operated under the control of the main controller 90 to detect the spatial position (the position of the XYZ coordinates) of the target object KT.

  Next, the timing for displaying an image on the image forming element 11 and the display position of the virtual image are determined from the spatial position of the target object KT, in particular, the distance from the pupil HT of the driver UN to the target object KT (step S14). . Specifically, main controller 90 determines the timing of displaying an image and the display position of a virtual image from the position data and the like of target object KT calculated by environment monitoring unit 72. The timing relates to the Z direction, and the display position relates to the XY directions. That is, the timing at which the image such as the display frame HW is displayed on the image forming element 11 is determined depending on the distance of the object KT.

  Next, an image is displayed on the image forming element 11 based on the timing and position information determined in step S14 (step S15). Specifically, the display controller 18 is operated under the control of the main controller 90 to cause the image forming element 11 to display a predetermined image at a predetermined timing. At this time, the display control unit 18 causes the image forming element 11 to display an image in synchronization with the movement of the image forming element 11 by the arrangement changing device 62 under the control of the main control device 90. In a screen corresponding to the display screen 20, for example, a display frame HW can be displayed as a display image (virtual image) IM corresponding to a plurality of objects KT.

  After step S15, when the operation of the display system for a mobile object is continued (Yes in step S16), the process returns to step S12.

  In the virtual image display device and the moving object display system described above, the driver (observer) UN changes the display image (virtual image) IM to 3 by associating the image forming element 11 as a drawing device and the arrangement changing device 62 with each other. A plurality of display images (virtual images) IM having different projection distances can be displayed so that they can be recognized two-dimensionally. By moving the image forming element 11 in the optical axis AX direction, the display image (virtual image) IM including the depth direction can be superimposed on the target object KT. Thereby, even when the target object KT exists in a range from a distant position to a nearby position, a shift between the target object KT and the display image (virtual image) IM due to the position of the eyes of the observer (driver UN) is reduced, and the safety is further improved. A simple driving support system can be realized. Therefore, even if the driver's viewpoint shifts, the positional relationship between the display image (virtual image) IM of the danger signal or the like and the real object (object KT) does not shift, so that it is possible to prevent the driver UN from being erroneously recognized.

〔Example〕
Hereinafter, specific examples of the head-up display device according to the present invention will be described.
In the data of the embodiment described below, Si (i = 0, 1, 2, 3,...) Is the i-th surface (the virtual image surface of the display image IM is the 0th plane). The first and second surfaces S1 and S2 following the zeroth surface S0 corresponding to the virtual image surface are virtual surfaces, and the third surface S3 corresponds to the pupil HT (see FIG. 4).

  The arrangement of each surface Si is specified by the surface vertex coordinates (x, y, z) and the rotation angle (ADE). The surface vertex coordinates of each surface Si are determined by using the surface vertex as the origin of the local rectangular coordinate system (X, Y, Z), and using the local rectangular coordinate system (X, y, z) in the local rectangular coordinate system (X, y, z). It is represented by the coordinates (x, y, z) of the origin of (Y, Z) (the unit is mm). The inclination of each surface Si is represented by an ADE or a rotation angle (α rotation) about the X axis centered on the surface vertex. The inclination of each surface Si is also represented by a BDE or a rotation angle (β rotation) around the Y axis centered on the surface vertex. The unit of the rotation angle is °, and the clockwise direction as viewed from the positive direction of the X axis is the positive direction of the rotation angle of α rotation, and the clockwise direction as viewed from the positive direction of the Y axis is β rotation. Is the positive direction of the rotation angle. The global rectangular coordinate system (x, y, z) is an absolute coordinate system that matches the local rectangular coordinate system (X, Y, Z) of the pupil HT or the pupil plane (third surface S3). . That is, the arrangement data of each surface Si is expressed in a global coordinate system with the origin at the center of the pupil plane. In the pupil plane (third surface S3), the direction from the display screen 20 toward the pupil HT is the + Z direction or + z direction, and the upward direction with respect to the pupil HT is the + Y direction or + y direction. ) The left direction viewed from the direction from 20 toward the pupil HT is the + X direction or + x direction.

ただし、
Ｚ ：Ｚ軸に平行な面のサグ量
ｃ ：頂点曲率（ｃ＝１／Ｒ）
ｋ ：円錐定数又はコーニック定数
Ｃ_ｊ：Ｘ^ｍＹ^ｎの係数
Ｒ ：Ｙ曲率半径In each embodiment, the fifth surface S5 and the sixth surface S6 corresponding to the virtual image forming optical system 17 are free-form surfaces, and the free-form surface shape has a vertex of the optical surface as an origin and a Z-axis in the optical axis direction. The sag amount Z of a plane parallel to the Z axis is represented by the following “Equation 1”.
[Equation 1]

However,
Z: sag amount of a surface parallel to the Z axis c: vertex curvature (c = 1 / R)
k: conic constant or conic constant _C ^j: X m ^Y coefficient ⁿ R: Y radius of curvature

  Hereinafter, specific examples of the head-up display device of the present invention will be described.

[Example 1]
Table 1 below shows the basic specifications of the head-up display device according to the first embodiment.
[Table 1]

Table 2 below shows data on the optical surface and the like of Example 1.
[Table 2]

Table 3 below shows the surface data of the mirror portion of the first embodiment. In the table, “*” represents a product, and “＾” represents a power.
[Table 3]

  Although the virtual image display device as a specific embodiment has been described above, the virtual image display device according to the present invention is not limited to the above. For example, in the above embodiment, the arrangement of the virtual image display device 100 may be turned upside down, and the display screen 20 may be arranged above the windshield 8 or at the position of the sun visor. In this case, the display screen 20 is disposed obliquely downward and forward of the drawing unit 10. In the above embodiment, the display screen 20 is a flat surface. However, the display screen 20 may be a curved surface, a curved surface that is further inclined, or a free-form surface having no symmetry.

  In the above-described embodiment, the outline of the display screen 20 is not limited to a rectangle, but may be various shapes.

  The main body optical system 13 shown in FIG. 3 and the like is merely an example, and the optical configuration of the main body optical system 13 can be appropriately changed. For example, one or more mirrors having no optical power may be arranged in the optical path of the virtual image forming optical system 17. In this case, it may be advantageous to reduce the size of the drawing unit 10 or the like by folding back.

  In the above embodiment, the display position of the display image (virtual image) IM can be set discretely, or can be set continuously or intermittently.

  In the above embodiment, the LCD is used as the drawing device, but another type of display element, for example, an organic EL may be used. In this case, the light distribution angle of the organic EL is wide, the viewing angle can be widened, and the virtual image display device 100 can be reduced in weight.

  In the above embodiment, the virtual image forming optical system 17 is provided with two mirrors. However, one or three or more mirrors may be provided. Further, the mirror may be omitted. Further, the optical surface of the mirror is a free-form surface having symmetry, but is not limited to this, and may be a free-form surface having no symmetry.

  In the above-described embodiment, the display screen 20 may be attached to the inside of a rectangular reflection region provided in front of the driver's seat of the windshield 8 or the windshield forming the front window without providing the combiner. Note that the display screen 20 can be embedded in the windshield 8.

  The virtual image display device 100 described above is not limited to a projection device mounted on an automobile or other moving object, but can be incorporated in digital signage or the like, but can be applied to other uses.

Claims (10)

A drawing device, an enlarged projection optical system for enlarging an image of the drawing device, and a virtual image display device including a display screen,
An arrangement changing device that changes the projection distance by moving the drawing device in the optical axis direction,
A display control unit that displays the plurality of virtual images having different projection distances by linking the drawing device and the arrangement changing device;
A virtual image display device comprising:   The virtual image display device according to claim 1, wherein, when receiving the position information of the object, the display control unit displays the virtual image in accordance with a position in the screen of the object corresponding to the display screen. .   The virtual image according to claim 1, wherein, when receiving the position information of the object, the display control unit adjusts the projection distance in accordance with a spatial position of the object. Display device.   The virtual image display device according to any one of claims 1 to 3, wherein the display control unit causes the drawing device to display an image in synchronization with movement of the drawing device by the arrangement change device.   The virtual image display device according to claim 1, wherein the drawing device operates at a frame rate of 60 fps or more.   The virtual image display device according to claim 1, wherein an amount of movement of the drawing device in an optical axis direction is equal to or less than 20 mm.   The virtual image display device according to any one of claims 1 to 6, wherein the arrangement changing device moves the drawing device at a speed of 15 Hz or more.   The virtual image display device according to any one of claims 1 to 7, wherein the drawing device is a liquid crystal display.   The virtual image display device according to any one of claims 1 to 7, wherein the drawing device is an organic EL. A virtual image display device according to any one of claims 1 to 9,
An environment monitoring unit that detects a spatial position of the object,
A display system for a mobile body comprising:

Images