JP2015184625A - Head-up display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a head-up display device for preventing a resolution from being deteriorated even when a virtual image is displayed at a far position from a user.SOLUTION: A video output from a projector 4 is projected to a screen 5, and a video projected to the screen 5 is reflected by a front window 6 of a vehicle 2 so as to be virtually recognized by a crew member 7 of the vehicle so that a virtual image 8 of the video to be visually recognized by the crew member 7 of the vehicle can be generated. Also, the screen 5 is movable along an optical path, and a generation distance as a distance from the crew member 7 of the vehicle to the virtual image 8 to be generated is changeable. Furthermore, when the screen is moved in a direction where the generation distance becomes long, a light source 15 is moved along the optical path to the screen 5 side so that a range where the video is projected to the screen 5 can be changed.

Description

  The present invention relates to a head-up display device that generates various images that are visually recognized by a user.

  Conventionally, various means have been used as information providing means for providing driving information such as route guidance and obstacle warnings to passengers of moving bodies such as vehicles. For example, display on a liquid crystal display installed on a moving body, sound output from a speaker, and the like. In recent years, as one of such information providing means, there is a head-up display device (hereinafter referred to as HUD).

  Here, for example, the HUD installed on the vehicle as a moving body is located in front of the vehicle window (for example, the front window) as seen from the vehicle occupant, as described in Japanese Patent Application Laid-Open No. 2009-150947. It is possible to generate driving information (for example, speed display, route guidance display, etc.) as a virtual image superimposed on the foreground of the front vision. As a result, the occupant can reduce the line-of-sight movement as much as possible when visually confirming the driving information, and can further reduce the burden during driving.

JP2009-150947A (page 5-6, FIG. 1)

  Here, in order to reduce the burden on the vehicle occupant during driving, it is important to appropriately set the position (more specifically, the distance from the occupant to the virtual image) where the virtual image is generated. For example, in order to generate a virtual image of a warning for an obstacle, it is desirable to generate a virtual image at a position where the obstacle actually exists. In addition, when generating a virtual image that guides a right or left turn of a road, it is desirable to generate a virtual image at a point where the right or left turns.

  The technique of Patent Document 1 discloses that the position of a screen that is a target for projecting an image from a projector is configured to be movable back and forth along an optical path, and the position for generating a virtual image is adjusted. . However, in the technique disclosed in Patent Document 1, the distance from the user to the virtual image can be arbitrarily changed, but the position of the light source is fixed. As a result, when generating a virtual image at a distance far from the user, the resolution of the virtual image is lower than when generating a virtual image at a distance close to the user.

  Specifically, as shown in FIG. 16, the amount of movement of the screen 101 necessary for displacing the position of the virtual image is extremely small compared to the amount of displacement of the virtual image. That is, when the position of the light source 102 is fixed, the range in which the image 103 is projected on the screen 101 is almost changed regardless of whether the distance from the user to the virtual image is 2.5 m or 20 m. No. That is, the size of the virtual image that the user can see after 2.5 m is almost the same as the size of the virtual image that the user can see after 20 m. For example, if the same size signboards are 2.5m and 20m away from the user, the signboard 20m away will look much smaller than the signboard 2.5m away, as you can see from the different distances. The fact that a virtual image of the same size can be seen means that the size of the virtual image farther away is larger.

  As a result, in the technique of the above-described Patent Document 1, as shown in FIG. For example, the virtual image 105 generated 2.5 meters ahead has a size of 30 inches, while the virtual image 106 generated 20 meters ahead has a size of 300 inches. Since the total number of pixels of the image does not change, as a result, the resolution (dpi) decreases as the virtual image is located farther from the user 104. For example, the resolution of the virtual image 106 generated 20 meters ahead is about 1/10 of the resolution of the virtual image 105 generated 2.5 meters ahead.

  The present invention has been made to solve the above-described conventional problems. By moving the light source along the optical path, it is possible to prevent the resolution from being lowered even when a virtual image is displayed far from the user. An object of the present invention is to provide a head-up display device.

In order to achieve the above object, a head-up display device (1) according to the present invention projects a screen (20, 21) and an image generated based on light output from a light source (15) onto the screen. (4), virtual image generating means (11, 12) for generating a virtual image of the video from the video projected on the screen, and screen moving means (24) for moving the screen along the optical path of the light source. A virtual image position for changing a generation distance which is a distance from a user viewing the virtual image to the virtual image generated by the virtual image generation unit by moving the screen along the optical path of the light source by the screen moving unit. The screen is moved in a direction in which the generation distance is increased by the changing means (31) and the screen moving means. And a light source moving means (17) for changing a range in which the image is projected onto the screen by moving the light source toward the screen along an optical path when moving the light source. And
The “light source” is used to project light output from a mirror, MEMS, DMD, color wheel, lens, etc. onto a screen in addition to a device that is an output supply source of light (for example, laser light or LED light). Also includes devices that reflect or process.

  According to the head-up display device according to the present invention having the above-described configuration, the light source can be moved along the optical path so that the light source is brought closer to the screen side even when a virtual image is displayed far from the user. Thus, it is possible to prevent the resolution of the generated virtual image from being lowered.

It is the figure which showed the installation aspect to the vehicle of HUD which concerns on this embodiment. It is the figure which showed the internal structure of HUD which concerns on this embodiment. It is the figure which showed the structure of the projector. It is the figure which showed the screen. It is the figure which showed the movement aspect to the front-back direction with respect to the optical path of a screen. It is the figure which showed the virtual image produced | generated by the image | video projected on the screen. It is the figure which showed the displacement of the projection range of the image | video on the screen accompanying the movement of a light source. It is the figure which showed the size and resolution of the virtual image visually recognized from the passenger | crew of a vehicle. It is the block diagram which showed the structure of HUD which concerns on this embodiment. It is a flowchart of the virtual image generation processing program which concerns on this embodiment. It is the figure which showed an example of the virtual image which can be visually recognized from the passenger | crew of a vehicle when a vehicle stops. It is the figure which showed an example of the virtual image which can be visually recognized from the passenger | crew of a vehicle at the time of driving | running | working of a vehicle. It is the figure which showed an example of the position setting table. It is the figure which showed the movement mode of the light source when obstacles, such as another vehicle used as a warning object, and a pedestrian, exist in front of the advance walk of the own vehicle. It is the figure which showed an example of the virtual image which can be visually recognized from the passenger | crew of a vehicle when obstacles, such as the other vehicle used as a warning object, and a pedestrian, exist in front of the advancing walk of the own vehicle. It is the figure shown about the problem of the prior art. It is the figure shown about the problem of the prior art.

  DESCRIPTION OF EMBODIMENTS Hereinafter, an embodiment embodying a head-up display device according to the present invention will be described in detail with reference to the drawings.

  First, the configuration of a head-up display device (hereinafter referred to as HUD) 1 according to the present embodiment will be described with reference to FIG. FIG. 1 is a diagram showing an installation mode of the HUD 1 according to the present embodiment on the vehicle 2.

  As shown in FIG. 1, the HUD 1 is installed inside the dashboard 3 of the vehicle 2, and includes a projector 4 and a screen 5 on which an image from the projector 4 is projected. Then, the image projected on the screen 5 is reflected on the front window 6 in front of the driver's seat through the mirror and Fresnel lens provided in the HUD 1 as will be described later, and is made visible to the passenger 7 of the vehicle 2. ing. Note that the image projected on the screen 5 includes information related to the vehicle 2 and various information used for assisting the driving of the occupant 7. For example, warnings for obstacles (other vehicles and pedestrians), guidance information set by the navigation device and guidance information based on the guidance route (such as arrows indicating the direction of turning left and right), current vehicle speed, guidance signs, map images, traffic information, There are news, weather forecast, time, screen of connected smartphone, TV program and so on.

  Further, in the HUD 1 of the present embodiment, when the occupant 7 visually recognizes an image projected on the screen 5 by reflecting the front window 6, the occupant 7 is not at the position of the front window 6 but at the front of the front window 6. An image projected on the screen 5 at a distant position is configured to be visually recognized as a virtual image 8. The virtual image 8 that can be seen by the occupant 7 is an image projected on the screen 5, but the vertical direction is reversed because the image is projected through the mirror. In addition, the size is changed by using a Fresnel lens.

  Here, regarding the position where the virtual image 8 is generated, more specifically, the distance L from the occupant 7 to the virtual image 8 (hereinafter referred to as a generation distance) L, the shape and position of the mirror and Fresnel lens provided in the HUD 1, and the screen 5 with respect to the optical path It is possible to appropriately set the position depending on the position. In particular, in the present embodiment, the position of the screen 5 is configured to be movable in the front-rear direction along the optical path as will be described later. As a result, the generation distance L can be changed as appropriate. For example, the generation distance L can be changed between 2.5 m and 20 m.

  Next, a more specific configuration of the HUD 1 will be described with reference to FIG. FIG. 2 is a diagram showing an internal configuration of the HUD 1 according to the present embodiment.

  As shown in FIG. 2, the HUD 1 basically includes a projector 4, a screen 5, a reflection mirror 10, a mirror 11, a Fresnel lens 12, a control circuit unit 13, and a CAN interface 14.

  Here, the projector 4 is an image projection apparatus using an LED light source, a lamp light source, or a laser light source as a light source, and is, for example, a laser scanning projector. The projector 4 may be a DLP projector, a liquid crystal projector, or an LCOS projector. When a projector other than the laser scanning projector is used, it is necessary to separately arrange a projection lens for the projector 4.

  FIG. 3 is a diagram showing the configuration of the projector 4. As shown in FIG. 3, the projector 4 includes a laser light source 15 inside. For example, in a laser scanning projector, the laser light output from the light source 15 is reflected by the MEMS mirror 16 and scanned on the screen 5. As a result, a desired image is projected onto the screen 5.

  Further, the projector 4 according to the present embodiment is configured such that the built-in light source 15 and the MEMS mirror 16 are integrally movable along the optical path. Specifically, as shown in FIG. 3, a drive mechanism 17 including an actuator and a circuit board is installed for the projector 4. By driving the drive mechanism 17, the entire projector 4 is connected to the light source 15 and the MEMS mirror 16. Are moved along the optical path. As a result, as described later, the projector 4 can change the range in which the image is projected onto the screen 5.

  On the other hand, the screen 5 is a projection medium on which an image projected from the projector 4 is projected. For example, a transmissive screen made of a diffusing plate such as ground glass or a microlens array is used. Here, FIG. 4 is a diagram showing the screen 5.

  As shown in FIG. 4, the screen 5 has a projection area 22 on which an image is projected, and an image projected from the projector 4 is displayed. The screen 5 is configured to be movable in the front-rear direction along the optical path. Specifically, by driving the screen front / rear drive motor 24 on the back side of the screen 5, as shown in FIG. 5, the screen 5 can be moved in the front / rear direction along the optical path. As a result, as shown in FIG. 6, it is possible to change the position (specifically, the generation distance L that is the distance from the occupant 7 to the virtual image 8) where the virtual image 8 of the image projected on the screen 5 is generated. is there. The generation distance L depends on the distance from the mirror 11 to the screen 5. That is, the generation distance L is changed in length depending on the distance from the mirror 11 to the screen 5. For example, the generation distance L increases as the distance from the mirror 11 to the screen 5 increases, and the generation distance L decreases as the distance from the mirror 11 to the screen 5 decreases.

  For example, when the screen 5 is moved to the projector 4 side (the side where the distance to the mirror 11 is increased), the generation distance L is increased (that is, the virtual image 8 is viewed farther from the occupant 7). . On the other hand, if the screen 5 is moved to the side opposite to the projector 4 (the side where the distance to the mirror 11 is shortened), the generation distance L is shortened (that is, the virtual image 8 is visually recognized closer to the passenger 7). Become).

  The screen front / rear drive motor 24 is a stepping motor. The HUD 1 controls the screen front / rear drive motor 24 based on the pulse signal transmitted from the control circuit unit 13, and can appropriately position the front / rear position of the screen 5 with respect to the set position.

  Further, in the present embodiment, when the screen 5 moves along the optical path, the projector 4 (light source 15) also moves along the optical path accordingly. Specifically, when the screen 5 is moved in the direction in which the generation distance L becomes longer as shown in FIG. 7, the projector 4 (light source 15) is moved to the screen 5 side along the optical path. Thereby, the range in which the image 25 is projected onto the screen 5 becomes narrower.

  Here, as described above, in the prior art, there is a problem that the virtual image generated at a position away from the occupant 7 is larger in size and the resolution is lowered (FIG. 17). However, in the HUD 1 according to the present embodiment, the resolution of the generated virtual image 8 is constant even when the generation distance L is changed by changing the projection range of the video 25 as shown in FIG. It becomes possible to do. For example, when the generation distance L is 20 m, the projector 4 is moved so that the light source 15 is closer to the screen 5 than when the generation distance L is 2.5 m, so that the image 25 projected on the screen 5 becomes smaller. That is, the size of the virtual image 8 that can be seen by the occupant 7 after 20 m is smaller than the size of the virtual image 8 that can be seen by the occupant 7 after 2.5 m. Accordingly, the virtual image 8 generated 2.5 m ahead and the virtual image 8 generated 20 m ahead can be adjusted to the same size of 30 inches. As a result, regardless of the distance from the occupant 7, the size of the generated virtual image 8 can be made the same size, and the resolution can be made constant. Note that the number of pixels of the image projected by the projector 4 is always constant (for example, 800 × 600) regardless of the position of the projector 4.

  On the other hand, the reflecting mirror 10 is a reflecting plate that reflects an image projected from the projector 4 to change the optical path and projects it onto the screen 5 as shown in FIG.

  Further, the mirror 11 reflects the image light from the screen 5 as shown in FIG. 2, and causes the occupant 7 to visually recognize the image of the screen 5 through the front window 6. 1). As the mirror 11, a spherical concave mirror, an aspheric concave mirror, or a free-form curved mirror for correcting distortion of a projected image is used. Since the image projected on the screen 5 is reflected by the reflecting mirror 10 and the mirror 11, the generated virtual image is an image obtained by inverting the image projected on the screen 5 vertically and horizontally.

  The Fresnel lens 12 is a magnifying glass for generating a virtual image 8 by enlarging the image projected on the screen 5 as shown in FIG. And in HUD1 which concerns on this embodiment, the image | video projected on the screen 5 is further reflected on the front window 6 via the mirror 11 and the Fresnel lens 12, and is made to be visually recognized by the passenger | crew 7, so that the front of the front window 6 is visible. The image projected on the screen 5 at a distant position is enlarged and is visually recognized by the occupant as a virtual image 8 (see FIG. 1).

  The control circuit unit 13 is an electronic control unit that controls the entire HUD 1. Here, FIG. 9 is a block diagram showing a configuration of the HUD 1 according to the present embodiment.

  As shown in FIG. 9, the control circuit unit 13 includes a CPU 31 as an arithmetic device and a control device, a RAM 32 used as a working memory when the CPU 31 performs various arithmetic processes, a control program, and a virtual image generation described later. A ROM 33 in which a processing program (see FIG. 10) and the like are recorded, an internal storage device such as a flash memory 34 for storing a program read from the ROM 33 and a position setting table to be described later are provided. The control circuit unit 13 is connected to the projector 4, the drive mechanism 17, and the screen front / rear drive motor 24, and performs drive control of the projector 4 and various motors and mechanisms.

  The CAN (controller area network) interface 14 is an interface for inputting / outputting data to / from CAN which is an in-vehicle network standard for performing multiplex communication between various on-vehicle devices installed in a vehicle and control devices for vehicle equipment. It is. The HUD 1 is connected to a control device (for example, the navigation device 48, the AV device 49, etc.) of various vehicle-mounted devices and vehicle equipment via the CAN so as to be able to communicate with each other. Accordingly, the HUD 1 is configured to be able to project output screens of the navigation device 48, the AV device 49, and the like.

  Next, a virtual image generation processing program executed by the CPU 31 in the HUD 1 having the above configuration will be described with reference to FIG. FIG. 10 is a flowchart of the virtual image generation processing program according to the present embodiment. Here, the virtual image generation processing program is executed after the ACC of the vehicle is turned on, generates a virtual image that is visible to the user who is a vehicle occupant, and moves the projector 4 (light source 15) in accordance with the movement of the screen. It is a program to be performed. Note that the program shown in the flowchart of FIG. 10 below is stored in the RAM 32 or ROM 33 provided in the HUD 1 and executed by the CPU 31.

  First, in step (hereinafter abbreviated as S) 1 in the virtual image generation processing program, the CPU 31 sets the positions of the screen 5 and the projector 4 (light source 15) to the initial positions. The initial position of the screen 5 is a position where the generation distance L, which is the distance from the occupant 7 to the virtual image 8, is the shortest distance (2.5 m in the present embodiment) within a changeable range. On the other hand, the position of the projector 4 (light source 15) is the position where the distance from the screen 5 is maximum, that is, the position where the projection range of the image onto the screen 5 is maximum. The initial position of the screen 5 may be a position where the generation distance L is other than 2.5 m. However, if the generation distance L that is the initial position is too long, the generated virtual image 8 is embedded in the road surface or the vehicle ahead, and therefore it is preferably about 2 m to 4 m.

  Next, in S <b> 2, the CPU 31 starts projecting an image on the screen 5 by the projector 4. Here, the video projected by the projector 4 includes information related to the vehicle 2 and various types of information used for assisting the driving of the occupant 7. For example, warnings for obstacles (other vehicles and pedestrians), guidance information set by the navigation device and guidance information based on the guidance route (such as arrows indicating the direction of turning left and right), current vehicle speed, guidance signs, map images, traffic information, There are news, weather forecast, time, connected smart phone screen, TV screen and so on. In particular, in the present embodiment, when the vehicle is stopped, an image of the current vehicle speed of the vehicle and a television screen are projected out of the images.

  As a result, as shown in FIG. 11, a numerical value indicating the current vehicle speed and a television screen are generated as a virtual image 8 near the lower edge of the front window 6 and 2.5 m ahead of the front window 6, and can be viewed by the passenger. Become.

  Next, in S3, the CPU 31 determines whether or not the vehicle has started running. For example, a vehicle speed sensor is used for the determination in S3.

  And when it determines with the vehicle having started driving | running | working (S3: YES), it transfers to S4. On the other hand, when it is determined that the vehicle is continuously stopped (S3: NO), the vehicle waits until the vehicle starts running.

  In S <b> 4, the CPU 31 transmits a signal to the projector 4, and ends the projection of the short-distance video that has been projected in S <b> 2.

  Next, in S5, the CPU 31 sets the generation distance L of the virtual image 8. Thereafter, the CPU 31 controls the position of the screen 5 so that the virtual image 8 is generated at a position away from the occupant 7 by the generation distance L set in S5 as described later. Here, the generation distance L set in S5 is a generation distance for generating the virtual image 8 at a position where the virtual image 8 needs to be generated for the current vehicle. Further, the position where the virtual image 8 needs to be generated is determined according to the situation of the traveling vehicle. For example, when a point where travel guidance such as a guidance intersection needs to be approached, the position is the position of the point.

  For example, as shown in FIG. 12, a case will be described in which an intersection 60 to be turned left and right approaches and a guide arrow indicating a right and left turn is displayed as the virtual image 8. First, the distance from the occupant 7 to the intersection 60 to be turned left and right is calculated based on the vehicle position and map information acquired from the navigation device, and the calculated distance is set as the generation distance L. As described above, the HUD 1 according to the present embodiment can change the generation distance L by moving the screen 5 in the front-rear direction along the optical path (see FIG. 5). Accordingly, the CPU 31 controls the position of the screen 5 so that the virtual image 8 is generated at a position separated from the occupant 7 by the generation distance L. As a result, the position where the virtual image 8 is generated is the position ahead of the generation distance L set by the occupant 7 (the position of the intersection 60 that is the target of a right turn in the example shown in FIG. 12). Accordingly, it is possible to associate the position of the virtual image 8 with the scenery in front of the occupant 7, and the occupant 7 can minimize the movement of the line of sight when viewing the virtual image 8. In addition, if the distance from the passenger | crew 7 to the intersection used as the right-left turn changes by a vehicle moving after that, it will comprise so that the production | generation distance L may also be changed in connection with it.

  Thereafter, in S6, the CPU 31 moves the screen 5 for generating the virtual image 8 at the generation distance L set in S5. Here, the position of the screen 5 is configured to be movable along the optical path of the light source 15 of the projector 4 as described above. Since the generation distance L depends on the distance from the mirror 11 to the screen 5, the position of the screen 5 is determined so that the distance from the mirror 11 to the screen 5 corresponds to the set generation distance L. The A position setting table stored in the flash memory 34 is used for determining the position of the screen 5. In the position setting table, for each generation distance L, the position of the screen 5 for generating the virtual image 8 is defined for the generation distance L as shown in FIG. Further, the CPU 31 transmits a pulse signal for driving the screen front-rear drive motor 24 to the screen front-rear drive motor 24 in order to move the screen 5 to the determined position. The screen front / rear drive motor 24 that has received the pulse signal drives based on the received pulse signal. As a result, the screen 5 moves to the target position.

  Subsequently, in S7, the CPU 31 also moves the projector 4 (light source 15) in accordance with the movement of the screen 5 in S6. Here, the projector 4 is configured such that the built-in light source 15 and the MEMS mirror 16 are integrally movable along the optical path as described above. When the screen 5 moves in the direction in which the generation distance L becomes longer, the projector 4 (light source 15) moves to the screen 5 side along the optical path with the number of pixels (for example, 800 × 600) fixed. . More specifically, the projector 4 (light source 15) is moved so as to satisfy the condition that the resolution of the virtual image 8 is always constant even when the generation distance L is changed as shown in FIG. A position setting table stored in the flash memory 34 is used for determining the position of the projector 4 (light source 15). In the position setting table, as shown in FIG. 13, for each generation distance L, the resolution of the generated virtual image 8 is made constant corresponding to the position of the screen 5 for generating the virtual image 8 at the generation distance L. The position of the projector 4 (light source 15) is also defined. Further, the CPU 31 transmits a drive signal for driving the actuator of the drive mechanism 17 to the drive mechanism 17 in order to move the projector 4 to the determined position. As a result, the projector 4 (light source 15) moves to the target position.

  Next, in S <b> 8, the CPU 31 starts projecting an image on the screen 5 by the projector 4. Here, the image projected by the projector 4 differs depending on the current vehicle situation. For example, in a situation where a point where traveling guidance such as a guidance intersection needs to be approached, an image relating to traveling guidance information (such as an arrow indicating a right or left turn at the intersection) is projected (see FIG. 12).

  Subsequently, in S9, the CPU 31 determines whether there is an obstacle such as another vehicle or a pedestrian that is a warning target in front of the forward walking of the host vehicle. Here, the HUD 1 according to the present embodiment warns the obstacle when there is an obstacle to be warned such as another vehicle that has interrupted in front of the forward walking of the own vehicle or a pedestrian that has jumped out. Do. And when warning is performed, it comprises so that a virtual image may be produced | generated in the position superimposed on this obstruction. Therefore, when warning an obstacle, it is desirable that a virtual image can be generated for a wider area. Therefore, the determination in S9 corresponds to a determination as to whether or not it is necessary to project an image on the screen 5 over a wide range.

  In addition, in order to determine whether there is an obstacle such as another vehicle or a pedestrian that is a warning target in front of the forward walking of the host vehicle, a captured image captured by a distance measuring sensor or a camera installed in the vehicle is used. Do it. For example, the distance sensor is always detected by a distance measuring sensor, and it is determined that the other vehicle has interrupted when the distance changes at least a predetermined amount at a time. Further, when an obstacle is newly detected within a predetermined distance ahead of the traveling direction of the vehicle, it is determined that the pedestrian has jumped out.

  When it is determined that there are obstacles such as other vehicles or pedestrians to be warned ahead of the forward walking of the host vehicle (S9: YES), that is, it is necessary to project an image on the screen 5 over a wide range. If it is determined that it has been, the process proceeds to S10. On the other hand, when it is determined that there are no obstacles such as other vehicles or pedestrians to be warned ahead of the forward walking of the host vehicle (S9: NO), that is, the image is projected over a wide range on the screen 5. If it is determined that there is no need, the process proceeds to S17.

  In S <b> 10, the CPU 31 transmits a signal to the projector 4, and temporarily interrupts the projection of the long-distance video that has been projected in S <b> 8.

  Subsequently, in S11, the CPU 31 moves the position of the projector 4 (light source 15) to the initial position. Here, the initial position is the position of the projector 4 (light source 15) corresponding to the position of the screen 5 that is the shortest distance (2.5 m in this embodiment) within the range in which the generation distance L can be changed. Is the position where the distance from the screen 5 is maximum, that is, the position where the projection range of the image onto the screen 5 is maximum. Here, as described above, the HUD 1 according to the present embodiment has a configuration in which the projector 4 moves along the optical path when the screen 5 is moved in order to keep the resolution of the generated virtual image 8 constant. Therefore, when the generation distance L is increased as shown in FIG. 7, the range in which an image can be projected by the projector 4 is reduced. As described above, when a warning is given to an obstacle, it is effective to generate a virtual image at a position superimposed on the obstacle. However, when the range in which an image can be projected by the projector 4 becomes small, the range becomes extremely narrow. There is a problem that a virtual image can be generated by superimposing only on an obstacle located. Accordingly, by moving the position of the projector 4 (light source 15) to the initial position as shown in FIG. Can be performed.

  Next, in S <b> 12, the CPU 31 starts projecting a warning video to the obstacle by the projector 4. As a result, as shown in FIG. 15, it is possible to generate a virtual image 8 that superimposes on the obstacle 61 and warns the obstacle. In the present embodiment, while the virtual image 8 that warns the obstacle is generated, the projection of the long-distance video started to be projected in S8 is interrupted. The projection may be continuously performed. In that case, a virtual image other than a warning (for example, a virtual image of a guide arrow at an intersection) is also generated at the same time.

  Subsequently, in S13, the CPU 31 determines whether or not to cancel the warning for the obstacle, that is, whether or not it is no longer necessary to project an image on the screen 5 over a wide range. For example, it is determined that the warning for the obstacle is to be canceled when the obstacle that has been a warning object has left the host vehicle or when a predetermined time has elapsed since the warning was started.

  If it is determined that the warning for the obstacle is to be canceled (S13: YES), that is, if it is determined that it is no longer necessary to project the video on the screen 5, the process proceeds to S14. On the other hand, if it is determined not to cancel the warning for the obstacle (S13: NO), that is, if it is determined that it is necessary to continuously project the image on the screen 5, it continues. To generate a virtual image of the warning for obstacles.

  In S <b> 14, the CPU 31 transmits a signal to the projector 4, and ends the projection of the video that warns the obstacle that has been projected in S <b> 12.

  Further, in S15, the CPU 31 drives the drive mechanism 17 to return the position of the projector 4 (light source 15) to the position immediately before the movement of S11.

  Next, in S <b> 16, the CPU 31 resumes the projection of the long-distance video by the projector 4 interrupted in S <b> 10. As a result, the virtual image 8 having the contents according to the current state of the vehicle (such as an arrow indicating a right / left turn at the intersection) is generated again.

  Thereafter, in S17, the CPU 31 determines whether or not the vehicle has stopped traveling. For example, a vehicle speed sensor is used for the determination in S17.

  And when it determines with the vehicle having stopped driving | running | working (S17: YES), it transfers to S18. On the other hand, when it is determined that the vehicle is in the running state (S17: NO), the process returns to S9, and the virtual image is continuously generated.

  In S18, the CPU 31 determines whether or not to end the projection of the video by the projector 4. For example, when the ACC of the vehicle is turned off, or when the shift position is set to “P”, it is determined that the projection of the video by the projector 4 is finished.

  And when it determines with complete | finishing the projection of the image | video by the projector 4 (S18: YES), the said virtual image generation process program is complete | finished. On the other hand, when it is determined that the projection of the image by the projector 4 is not finished (S18: NO), the process returns to S1, and the position of the screen 5 or the projector 4 is returned to the initial position, and then the image for short distance is used. Project.

  As described above in detail, according to the HUD 1 according to the present embodiment, an image output from the projector 4 is projected on the screen 5, and the image projected on the screen 5 is reflected on the front window 6 of the vehicle 2 to By making the occupant 7 visually recognize, a virtual image 8 of an image visually recognized by the occupant 7 of the vehicle is generated. The screen 5 is movable along the optical path, and the generation distance, which is the distance from the vehicle occupant 7 to the virtual image 8 generated, can be changed. Further, when the screen is moved in the direction in which the generation distance becomes longer, the range in which the image is projected onto the screen 5 is changed by moving the light source 15 toward the screen 5 along the optical path (S7). Therefore, even when the virtual image 8 is displayed far from the vehicle occupant 7, it is possible to prevent the resolution of the generated virtual image 8 from being lowered by bringing the light source 15 closer to the screen 5 side. Become.

Note that the present invention is not limited to the above-described embodiment, and various improvements and modifications can be made without departing from the scope of the present invention.
For example, in the present embodiment, the virtual image is generated in front of the front window 6 of the vehicle 2 by the HUD 1, but the virtual image may be generated in front of a window other than the front window 6. In addition, the object to be reflected by the HUD 1 may be a visor (combiner) installed around the front window 6 instead of the front window 6 itself.

  In the present embodiment, the HUD 1 is installed on the vehicle 2. However, the HUD 1 may be installed on a moving body other than the vehicle 2. For example, it can be installed on a ship or an aircraft. Moreover, you may install in the ride type attraction installed in an amusement facility. In that case, a virtual image can be generated around the ride so that the rider can visually recognize the virtual image.

  Further, in the present embodiment, the light source 15 is moved along the optical path by moving the entire apparatus of the projector 4, but only the light source 15 and the MEMS mirror 16 are moved without moving the entire apparatus of the projector 4. It is good also as a structure which moves.

  In this embodiment, a laser scanning projector that does not require a projection lens is used, but a projector other than the laser scanning projector (for example, a DLP projector, a liquid crystal projector, or an LCOS projector) may be used. In that case, the projection lens is moved together with the light source. Moreover, it is good also as a structure which fixes the position of a light source and moves a projection lens along the optical path of a light source. Even in that case, it is possible to change the range in which the image is projected onto the screen 5 and to achieve the object of the present invention.

  Also, in this embodiment, the case where there is an obstacle such as another vehicle or a pedestrian that is a warning target in front of the forward walking of the own vehicle is defined as a case where it is necessary to project a wide range of images on the screen. However, other conditions may be satisfied. For example, it may be a condition that a virtual image of guidance or warning needs to be generated for a wider range when traveling on a busy road or traveling on a wide road.

  In this embodiment, the movable range of the screen 5 is set so that the generation distance L is displaced between 2.5 m and 20 m. However, the lower limit and the upper limit of the generation distance L can be changed as appropriate. is there.

  In this embodiment, the screen is composed of one screen, but the number of screens may be two or more. When two or more screens are used, all the screens may be configured to be movable along the optical path, or only a part of the screens may be configured to be movable along the optical path. Further, when the number of screens is two or more, the range in which an image is projected for each screen can be changed by making the number of projectors correspond to the number of screens.

  Moreover, although the embodiment which actualized the head-up display device according to the present invention has been described above, the head-up display device can also have the following configuration, and in that case, the following effects can be obtained.

For example, the first configuration is as follows.
A screen, a projector that projects an image generated based on light output from a light source onto the screen, a virtual image generation unit that generates a virtual image of the image from the image projected on the screen, and the screen Screen moving means for moving along the optical path of the light source, and the virtual image generated by the virtual image generating means from the user viewing the virtual image by moving the screen along the optical path of the light source by the screen moving means. A virtual image position changing unit that changes a generation distance that is a distance to the screen, and when the screen is moved in a direction in which the generation distance is increased by the screen moving unit, the light source is moved to the screen side along an optical path. Range in which the image is projected on the screen by moving the screen And having a light source moving means for changing.
According to the head-up display device having the above configuration, the light source is configured to be movable along the optical path, thereby generating the light source by bringing the light source closer to the screen side even when displaying a virtual image far from the user. It is possible to prevent the resolution of the virtual image to be lowered.

The second configuration is as follows.
The light source moving means moves the light source in a state where the number of pixels of the video projected on the screen is fixed.
According to the head-up display device having the above configuration, the virtual image is displayed far from the user only by moving the light source along the optical path without changing the number of pixels of the video output from the projector. However, it is possible to prevent the resolution of the generated virtual image from being lowered. Therefore, it is possible to reduce a control burden related to video display control in the projector.

The third configuration is as follows.
The light source moving means moves the light source so that the resolution of the virtual image is constant even when the generation distance is changed.
According to the head-up display device having the above configuration, the resolution of the generated virtual image is made constant regardless of how the generation distance is changed by moving the light source along the optical path according to the movement of the screen. Is possible. Therefore, the visibility of the generated virtual image can be improved.

The fourth configuration is as follows.
A projection determining means for determining whether or not it is necessary to project the image over a wide range on the screen in a state where the light source is moved to the screen side along the optical path by the light source moving means; Light source re-moving means for moving the light source in the direction away from the screen along the optical path when it is determined by the projection determining means that the image needs to be projected over a wide range on the screen. It is characterized by that.
According to the head-up display device having the above-described configuration, when it is necessary to project an image over a wide range for a warning to an obstacle, the light source is temporarily moved along the optical path in a direction away from the screen. By doing so, it becomes possible to project an image over a wide range on the screen. As a result, it is possible to appropriately provide necessary information to the user by the virtual image by expanding the projection range of the video when necessary while preventing the resolution of the virtual image from being lowered.

The fifth configuration is as follows.
In a state where the light source is moved in the direction away from the screen along the optical path by the light source re-moving means, the position of the light source is determined when it is no longer necessary to project the image on the screen over a wide range. It has a light source returning means for returning to a position before moving by the light source re-moving means.
According to the head-up display device having the above configuration, when the warning for the obstacle is finished and it is no longer necessary to project the video over a wide range, the resolution of the virtual image is lowered by returning the light source to the original position. This can be prevented as much as possible.

DESCRIPTION OF SYMBOLS 1 Head up display apparatus 2 Vehicle 3 Dashboard 4 Projector 5 Screen 6 Front window 7 Crew 8 Virtual image 15 Light source 17 Drive mechanism 24 Screen front-rear drive motor 31 CPU
32 RAM
33 ROM
34 Flash memory

Claims (5)

Screen,
A projector that projects an image generated based on light output from a light source onto the screen;
Virtual image generating means for generating a virtual image of the video from the video projected on the screen;
Screen moving means for moving the screen along the optical path of the light source;
A virtual image position change that changes a generation distance that is a distance from a user viewing the virtual image to the virtual image generated by the virtual image generation unit by moving the screen along the optical path of the light source by the screen moving unit. Means,
When the screen is moved in the direction in which the generation distance is increased by the screen moving means, the video is projected onto the screen by moving the light source along the optical path toward the screen. And a light source moving means for changing the range.   2. The head-up display device according to claim 1, wherein the light source moving unit moves the light source in a state where the number of pixels of the video projected on the screen is fixed.   The head-up display according to claim 1, wherein the light source moving unit moves the light source so that the resolution of the virtual image is constant even when the generation distance is changed. apparatus. A projection determination unit that determines whether or not the image needs to be projected over a wide range on the screen in a state where the light source is moved to the screen side along the optical path by the light source moving unit;
A light source re-moving means for moving the light source in a direction away from the screen along the optical path when it is determined by the projection determining means that the image needs to be projected over a wide range on the screen; The head-up display device according to claim 1, wherein the head-up display device is provided.   In a state where the light source is moved in the direction away from the screen along the optical path by the light source re-moving means, the position of the light source is determined when it is no longer necessary to project the image on the screen over a wide range. 5. The head-up display device according to claim 4, further comprising light source return means for returning to a position before being moved by the light source re-moving means.

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