JP2015178297A - Head-up display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a head-up display device capable of allowing a user to accurately discern a virtual image irrespective of an ambient environment.SOLUTION: A projector 4 projects a picture on a stationary first screen 20 and movable second screen 21. The picture projected on the first screen 20 and second screen 21 is reflected on a front window 6 of a vehicle so that an occupant 7 of the vehicle can discern the picture. Thus, a virtual image of the picture which the occupant 7 of the vehicle discerns is produced. For producing the virtual image, an ambient environment at a position at which the virtual image is produced is acquired. Based on the acquired ambient environment, the luminance of a light source 19 of the projector 4 and luminosities of color components (red, green, and blue) of a picture to be projected are adjusted.

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, a HUD installed on a vehicle as a moving body is located in front of a vehicle window (for example, a front window) as seen from a vehicle occupant as described in Japanese Patent Application Laid-Open No. 2011-93413. It is possible to generate a virtual image superimposed on the foreground of the front visual field. 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.

JP 2011-93413 A (page 3, FIG. 1)

  Here, when generating a virtual image such as route guidance or an obstacle warning, it is important that the virtual image can be clearly seen by the user in order to make the user surely understand the contents of the guidance and warning. However, when the front visual field in which the virtual image is generated is particularly bright, there is a problem that the generated virtual image is difficult to see from the user.

  Therefore, Patent Document 1 proposes a technique for detecting the brightness of the surroundings of the vehicle with a sensor and adjusting the brightness of the light source of the projector so that the user can easily see the virtual image according to the detected surrounding brightness. Has been. However, since the technique disclosed in Patent Document 1 performs display correction of a virtual image only by adjusting the luminance of the light source, it can be corrected only within the adjustment range of the luminance of the light source. For example, when the surroundings are bright, it is necessary to increase the luminance of the light source accordingly, but no further correction can be made after the luminance of the light source reaches the upper limit.

  The present invention has been made to solve the above-described conventional problems, and by adjusting the brightness of each element of red, green, and blue representing each pixel constituting an image in addition to the luminance of the light source. It is an object of the present invention to provide a head-up display device that can perform display correction of a virtual image in a wider range and can clearly make a user visually recognize a virtual image regardless of the surrounding environment.

  In order to achieve the above object, a head-up display device (1) according to the present invention includes a screen (5) and a projector (4) that projects an image generated on the screen based on light output from a light source (19). ), Virtual image generation means (11, 12) for generating a virtual image of the video from the video projected on the screen, light source adjustment means (31) for adjusting the luminance of the light source, and each of the video RGB adjustment means (31) that adjusts the brightness of each element of red, green, and blue representing pixels, and environment acquisition means (31) that acquires the surrounding environment at the position where the virtual image is generated, The light source adjustment unit and the RGB adjustment unit adjust the luminance of the light source and the brightness of each element based on the surrounding environment acquired by the environment acquisition unit.

  According to the head-up display device according to the present invention having the above-described configuration, red, green, and blue representing each pixel that constitutes an image in addition to the luminance of the light source based on the surrounding environment where the virtual image is generated. Since the brightness of each element is also adjusted, display correction of a virtual image can be performed in a wider range than in the past. As a result, it becomes possible for the user to clearly see the virtual image regardless of the surrounding environment. In particular, even if the position where the virtual image is generated is in a very bright state due to the strong reflection of the sun, the generated virtual image can be appropriately viewed by the user.

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 movement aspect of the 2nd projection lens. It is the figure which each showed the 1st screen and the 2nd screen. It is the figure which showed the projection aspect of the image | video of the projector with respect to the 1st screen and the 2nd screen. It is the figure which showed the movement aspect to the front-back direction with respect to the optical path of a 2nd screen. It is the figure which each showed the virtual image produced | generated by the image | video projected on the 1st screen and the 2nd screen. It is the figure which showed the movement aspect to the crossing direction with respect to the optical path of a 1st screen and a 2nd screen. It is the figure which showed the projection aspect of the image | video of a projector at the time of moving a 1st screen and a 2nd screen to an up-down direction. It is the block diagram which showed the structure of HUD which concerns on this embodiment. It is a flowchart of a display correction processing program according to the present embodiment. It is a flowchart of a display correction processing program according to the present embodiment. It is the figure which showed the correspondence of the illumination intensity around the position where a virtual image is produced | generated, and the brightness | luminance of the light source of a projector. It is the figure which showed an example of the virtual image visually recognizable from the passenger | crew of a 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 the position where a virtual image is produced | generated is in a very bright state.

  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.

  A front camera 9 is installed above the front bumper of the vehicle 2. Here, the front camera 9 is configured by a camera using a solid-state imaging device such as a CCD, for example, and is installed with the optical axis direction directed toward the occupant 7's line of sight. And the position where the virtual image 8 is produced | generated is imaged from the passenger | crew 7 side. More specifically, the optical axis and the imaging range are designed so as to capture a range in which a virtual image can be generated by the HUD 1. The HUD 1 specifies the surrounding environment at the position where the virtual image is generated based on the captured image captured by the front camera 9 as will be described later, and corrects the display of the virtual image 8 so that the occupant 7 can easily see the virtual image 8. Do.

  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 a video projection device using an LED light source or a lamp light source as a light source, and is a DLP projector, for example. As the projector 4, a liquid crystal projector or an LCOS projector may be used.

  FIG. 3 is a diagram showing the configuration of the projector 4. As shown in FIG. 3, the projector 4 includes a light source 19 inside. For example, in a single-plate DLP projector, light output from the light source 19 is passed through a color wheel (not shown) and then reflected by a digital mirror device. Then, an image is projected onto the screen 5 through the projection lens 15. Further, the projector 4 according to the present embodiment is configured so that the luminance of the light source 19 can be adjusted within a preset range. Furthermore, the brightness of each element of red, green, and blue representing each pixel constituting the projected image is configured to be adjustable.

  The projector 4 includes a projection lens 15 for projecting an image. In this embodiment, the projection lens 15 is composed of two projection lenses, a first projection lens 16 and a second projection lens 17, which are different from each other. Configure to project video.

  As shown in FIG. 3, the first projection lens 16 and the second projection lens 17 have a divided shape obtained by dividing one circular lens in the vertical direction. Further, the second projection lens 17 below is configured to be movable in the front-rear direction along the optical path. On the other hand, the position of the first projection lens 16 is fixed. Specifically, by driving the lens drive motor 18 on the back side of the second projection lens 17, it is possible to move the second projection lens 17 in the front-rear direction along the optical path as shown in FIG. Become. In particular, in this embodiment, when the screen 5 is moved in the front-rear direction along the optical path as will be described later, the focal point of the image projected from the second projection lens 17 is made to coincide with the position of the screen 5 after the movement. In addition, the second projection lens 17 is also moved to follow.

  The lens drive motor 18 is a stepping motor. The HUD 1 can control the lens driving motor 18 based on the pulse signal transmitted from the control circuit unit 13 and appropriately position the second projection lens 17 with respect to the set position.

  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. In the present embodiment, the screen 5 includes two screens, a first screen 20 and a second screen 21. Here, FIG. 5 is a view showing the first screen 20 and the second screen 21.

  As shown in FIG. 5, the first screen 20 has a projection area 22 on which an image is projected upward, and is normally projected from the first projection lens 16 of the projector 4 as shown in FIG. Displayed. On the other hand, the second screen 21 has a projection area 23 on which an image is projected below. In a normal state, the image projected from the second projection lens 17 of the projector 4 is displayed as shown in FIG. Is done. That is, the projection range of the image by the projector 4 is set across the first screen 20 and the second screen 21. Further, as will be described later, in the present embodiment, the first screen 20 and the second screen 21 are configured to be movable in a direction that intersects the optical path integrally, and as a result, are projected from the first projection lens 16. A part of the image may be projected onto the second screen 21 or a part of the image projected from the second projection lens 17 may be projected onto the first screen 20 (see FIG. 10).

  Further, as shown in FIGS. 2 and 6, the first screen 20 and the second screen 21 are arranged side by side at predetermined intervals in the front-rear direction along the optical path so that the projection areas 22 and 23 do not overlap. Therefore, in the present embodiment, the virtual image 8 includes a virtual image of a video projected on the first screen 20 (hereinafter referred to as a first virtual image 8A) and a virtual image of a video projected on the second screen 21 (hereinafter referred to as a second virtual image 8B). It will be composed of.

  The second screen 21 is configured to be movable in the front-rear direction along the optical path. On the other hand, the position of the first screen 20 is fixed with respect to the front-rear direction. Specifically, the distance between the first screen 20 and the second screen 21 is changed as shown in FIG. 7 by driving the screen front / rear drive motor 24 on the back side of the second screen 21. The two screens 21 can be moved in the front-rear direction along the optical path. As a result, the position where the second virtual image 8B, which is the virtual image of the image projected on the second screen 21, is generated (specifically, the generation distance L2 that is the distance from the occupant 7 to the second virtual image 8B) is changed. Is possible. The generation distance L2 depends on the distance from the mirror 11 to the second screen 21. That is, the generation distance L <b> 2 is changed in length depending on the distance from the mirror 11 to the second screen 21. For example, the generation distance L2 increases as the distance from the mirror 11 to the second screen 21 increases, and the generation distance L2 decreases as the distance from the mirror 11 to the second screen 21 decreases.

  For example, when the second screen 21 is moved to the projector 4 side (the side where the distance to the mirror 11 is increased), the generation distance L2 is increased (that is, the second virtual image 8B is viewed farther from the passenger 7). It becomes like). On the other hand, when the second screen 21 is moved to the side opposite to the projector 4 (the side where the distance to the mirror 11 is shortened), the generation distance L2 is shortened (that is, the second virtual image 8B is visible closer to the occupant 7). Will come to be). Since the position of the first screen 20 is fixed in the front-rear direction, the position (specifically, from the occupant 7 to the first virtual image 8A, which is a virtual image of the image projected on the first screen 20). The generation distance L1) that is the distance to one virtual image 8A is fixed. That is, by changing the generation distance L2, the distance (| L2-L1 |) from the first virtual image 8A to the second virtual image 8B is changed.

  Therefore, if the first screen 20 and the second screen 21 are at the same distance from the mirror 11 along the optical path, the first virtual image 8A and the second virtual image 8B are generated at the same position in front of the vehicle 2. However, when the first screen 20 and the second screen 21 are at different distances from the mirror 11 along the optical path, the first virtual image 8A and the second virtual image 8B are at different positions as shown in FIG. Will be generated. Further, as shown in FIGS. 5 and 6, each screen is arranged so that the projection area 22 of the first screen 20 is positioned above the projection area 23 of the second screen 21, but the mirror 11. Thus, the image is inverted upside down, so that the second virtual image 8B is generated above the first virtual image 8A with reference to the direction intersecting the optical path.

  In the present embodiment, the first screen 20 and the second screen 21 are configured to be integrally movable in a direction crossing the optical path. Specifically, by driving a screen up / down drive motor 25 on the side surface of the first screen 20, the first screen 20, the second screen 21, and the screen front / rear drive motor 24 are integrated with each other as shown in FIG. It is possible to move in a direction that intersects (more specifically, a vertical direction that is the arrangement direction of the first screen 20 and the second screen 21). As a result, as shown in FIG. 10, the first projection mode in which the image from the projector 4 is projected on the first screen 20 and the second screen 21, and the image from the projector 4 on the first screen 20 only. The projection mode of the image on the screen 5 can be switched between the second projection mode to be projected.

  When the projection mode is the first projection mode, the HUD 1 basically has different types of video images (for example, the first projection lens 16 presents the current vehicle state) between the first projection lens 16 and the second projection lens 17. The vehicle speed image and the second projection lens 17 project guidance information and warning information image) on each screen. On the other hand, when the projection mode is the second projection mode, one video (for example, the first projection lens 16) that is basically a combination of the images projected by the first projection lens 16 and the second projection lens 17. Then, the image on the lower half of the television screen is projected on the first screen 20 and the image on the upper half of the television screen is projected on the second projection lens 17. As a result, in the second projection mode, it is possible to generate a larger-size image without a dividing line as a virtual image. Even in the second projection mode, the first projection lens 16 and the second projection lens 17 may be configured to project different types of images.

  Each of the screen front / rear drive motor 24 and the screen vertical drive motor 25 is a stepping motor. Then, the HUD 1 can control the screen front / rear drive motor 24 based on the pulse signal transmitted from the control circuit unit 13 and appropriately position the front / rear position of the second screen 21 with respect to the set position. The HUD 1 controls the screen vertical drive motor 25 based on the pulse signal transmitted from the control circuit unit 13 and appropriately positions the vertical positions of the first screen 20 and the second screen 21 with respect to the set position. Is possible.

  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 first screen 20 and the second screen 21 is reflected by the reflecting mirror 10 and the mirror 11, the generated virtual image is projected on the first screen 20 and the second screen 21. The resulting image is an inverted image of the top, bottom, left and right.

  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. 11 is a block diagram showing the configuration of the HUD 1 according to the present embodiment.

  As shown in FIG. 11, 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 display correction described later. A ROM 33 in which a processing program (see FIG. 12) 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 luminance setting table to be described later are provided. The control circuit unit 13 is connected to the projector 4, the lens drive motor 18, the screen front / rear drive motor 24, and the screen vertical drive motor 25.

  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.

  In addition to the front camera 9 described above, an illuminance sensor 50 is also connected to the HUD 1. Here, the illuminance sensor 50 is a sensor that is installed on the outer wall of the vehicle and detects the illuminance around the vehicle (that is, the position where the virtual image is generated). And HUD1 specifies the surrounding environment of the position where a virtual image is produced | generated based on the detection result of the illumination intensity sensor 50 so that it may mention later, and the display correction of the virtual image 8 is performed so that the passenger | crew 7 can visually recognize the virtual image 8 easily.

  Next, a display correction processing program executed by the CPU 31 in the HUD 1 having the above configuration will be described with reference to FIGS. 12 and 13 are flowcharts of the display correction processing program according to this embodiment. Here, the display correction processing program is executed after the ACC of the vehicle is turned on, and generates a virtual image 8 to be visually recognized from the occupant 7 and performs display correction of the virtual image 8 so that the occupant 7 can easily view the virtual image. It is a program. The following programs shown in the flowcharts of FIGS. 12 and 13 are stored in the RAM 32 and the ROM 33 provided in the HUD 1 and executed by the CPU 31. In the following description, it is assumed that the image projection mode onto the screen 5 is always in the first projection mode (FIG. 10).

  First, in step (hereinafter abbreviated as S) 1 in the display correction processing program, the CPU 31 determines whether or not a condition for displaying a virtual image by the HUD 1 is satisfied. Here, the virtual image generated by the HUD 1 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, screen of connected smartphone, TV program and so on. Therefore, in S1, it is determined whether or not the condition for displaying any one of the virtual images is satisfied. For example, when the vehicle approaches within a predetermined distance (for example, 300 m) from the guidance intersection, it is determined that the condition for displaying a virtual image related to the guidance information is satisfied, and an obstacle (pedestrian or other vehicle) approaches the front of the vehicle. In such a case, it is determined that a condition for displaying a virtual image related to a warning for an obstacle is satisfied.

  And when it determines with satisfy | filling the conditions which display a virtual image (S1: YES), it transfers to S2. On the other hand, when it is determined that the condition for displaying the virtual image is not satisfied (S1: NO), the display correction processing program is terminated without generating the virtual image by the HUD 1.

  Next, in S2, the CPU 31 acquires the illuminance around the position where the virtual image is generated from the detection result of the illuminance sensor 50 installed in the vehicle. Note that means other than the illuminance sensor 50 may be used for detecting the illuminance. For example, it is good also as a structure detected from the image imaged with the front camera 9. FIG.

  Subsequently, in S3, the CPU 31 determines whether or not the illuminance around the position where the virtual image acquired in S2 is generated is less than a predetermined reference illuminance. Here, as described later, until the luminance of the light source 19 of the projector 4 reaches the upper limit value, the CPU 31 adjusts the luminance of the light source 19 of the projector 4 to be higher as the illuminance acquired in S2 is higher. (S4, S5). The reference illuminance that is the determination criterion in S3 is the illuminance at which the luminance of the light source 19 of the projector 4 reaches the upper limit (see FIG. 14).

  When it is determined that the illuminance around the position where the virtual image acquired in S2 is generated is less than the predetermined reference illuminance (S3: YES), the process proceeds to S4. On the other hand, when it is determined that the illuminance around the position where the virtual image acquired in S2 is generated is greater than or equal to a predetermined reference illuminance (S3: NO), the process proceeds to S8.

  In S4, the CPU 31 reads the luminance setting table from the flash memory 34, and specifies the luminance of the light source 19 of the projector 4 corresponding to the illuminance acquired in S2. Here, the luminance setting table is a table in which a correspondence relationship between the illuminance around the position where the virtual image is generated and the luminance of the light source 19 of the projector 4 is defined. The brightness at which the virtual image generated from the vehicle occupant is most easily seen is defined. Specifically, as shown in FIG. 14, it is defined that the luminance of the light source 19 of the projector 4 becomes higher as the illuminance around the position where the virtual image is generated is higher. When the illuminance around the position where the virtual image is generated is equal to or higher than the reference illuminance, an upper limit value is set for the luminance of the light source 19 of the projector 4 as described later (S8). In the example shown in FIG. 14, the illuminance around the position where the virtual image is generated and the luminance of the light source 19 of the projector 4 have a linear direct proportional relationship, but may be a correspondence relationship that draws an exponential curve. .

  Thereafter, in S5, the CPU 31 transmits a signal to the projector 4, and sets the luminance of the light source 19 of the projector 4 to the luminance specified in S4. As a result, even when the illuminance around the position where the virtual image is generated is high, the virtual image can be displayed with a luminance corresponding to the illuminance, and the occupant can clearly see the generated virtual image.

  Subsequently, in S6, the CPU 31 transmits a signal to the projector 4, and starts projecting an image on the first screen 20 and the second screen 21 by the projector 4 with the luminance of the light source 19 set in S4. 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 (an arrow indicating a right / left turn of a guidance intersection, an arrow indicating a lane change, etc.) is projected. In addition, when an obstacle such as an interrupting vehicle newly appears in front of the vehicle, a video regarding warning information (such as a frame surrounding the obstacle) to the obstacle is projected. Further, in the HUD 1 according to the present embodiment, the position of the second virtual image 8B generated based on the second screen 21 (specifically, by moving the position of the second screen 21 along the optical path as described above, specifically, Can change the generation distance L2), which is the distance from the vehicle occupant 7 to the second virtual image 8B.

  For example, as shown in FIG. 15, a case will be described in which an intersection 60 to be turned right and left approaches and a guidance arrow indicating a right and left turn is displayed as the second virtual image 8B. 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 L2. As described above, the HUD 1 according to the present embodiment can change the generation distance L2 by moving the second screen 21 in the front-rear direction along the optical path (see FIG. 7). Accordingly, the CPU 31 controls the position of the second screen 21 so that the second virtual image 8B is generated at a position away from the occupant 7 by the generation distance L2. As a result, the position at which the second virtual image 8B is generated is a position in front of the generation distance L2 set by the occupant 7 (the position of the intersection 60 that is a left turn target in the example illustrated in FIG. 15). Therefore, it becomes possible to make the front scenery visually recognized by the occupant 7 correspond to the position of the second virtual image 8B, and the occupant 7 can minimize the movement of the line of sight even when viewing the second virtual image 8B. . Further, as shown in FIG. 15, even when there are a plurality of intersections, it is possible to easily identify the intersection to be turned right or left. 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 L2 may also be changed in connection with it.

  Thereafter, in S7, the CPU 31 determines whether or not a condition for terminating the display of the virtual image is satisfied. The condition for terminating the display of the virtual image differs depending on the type of virtual image to be displayed. For example, for a virtual image indicating guidance information (such as an arrow indicating a right / left turn direction) at a guidance intersection, it is determined that a condition for ending the display of the virtual image is satisfied when the vehicle passes the guidance intersection. For a virtual image indicating a warning for an obstacle, it is determined that a condition for ending the display of the virtual image is satisfied when a predetermined time has elapsed since the virtual image was displayed, or when the corresponding obstacle has left the vehicle.

  And when it determines with satisfy | filling the conditions which complete | finish the display of a virtual image (S7: YES), the production | generation of the virtual image by HUD1 is complete | finished. On the other hand, when it is determined that the condition for ending the display of the virtual image is not satisfied (S7: NO), the process returns to S2, and the virtual image is continuously generated by HUD1. If the surrounding environment (illuminance or the like) changes after the display of the virtual image is changed, display correction of the virtual image being displayed is performed in accordance with the processing after S2.

  On the other hand, in S8, the CPU 31 transmits a signal to the projector 4, and sets the brightness of the light source 19 of the projector 4 to a settable upper limit value.

  Next, in S9, the CPU 31 acquires a captured image of the front camera 9. As shown in FIG. 1, the front camera 9 has an optical axis and an imaging range designed to capture a position where a virtual image is generated from the occupant 7 side (more specifically, a range where a virtual image can be generated by the HUD 1). Has been.

  Subsequently, in S10, the CPU 31 extracts the luminance component of each pixel constituting the captured image from the captured image of the front camera 9 acquired in S9.

  In S11, the CPU 31 calculates the average value of the luminance components acquired in S10. Note that the average value of the luminance component calculated in S11 is stored in the flash memory 34 or the like.

  Thereafter, in S12, the CPU 31 determines each element (hereinafter referred to as R (red), G (green), and B (blue)) representing each pixel constituting the captured image from the captured image of the front camera 9 acquired in S9. The brightness of the color component).

  Subsequently, in S13, the CPU 31 specifies, from among R (red), G (green), and B (blue), the color component having the highest brightness in the captured image among the brightness of each color component acquired in S12. . Specifically, the average value of the brightness of each color component in the captured image is calculated, and the color component having the highest average value is specified. The color component specified in S13 is stored in the flash memory 34 or the like.

  Next, in S14, the CPU 31 determines whether or not the average value of the luminance components of the captured image calculated in S11 is equal to or greater than a predetermined threshold. The threshold value used as the determination criterion in S14 is the lower limit value of the luminance at which the reflection around the sun around the vehicle is particularly strong and the virtual image cannot be visually recognized by the occupant 7 with normal display correction. In addition, the threshold value is basically set to a value higher than the luminance of the captured image captured by the front camera 9 when the illuminance detected by the illuminance sensor 50 is the reference illuminance.

  And when it determines with the average value of the luminance component of the captured image calculated by said S11 being more than a predetermined threshold value (S14: YES), it transfers to S22. On the other hand, when it is determined that the average value of the luminance components of the captured image calculated in S11 is less than the predetermined threshold (S14: NO), the process proceeds to S15.

  In S15, the CPU 31 determines whether or not the color component having the highest brightness in the captured image specified in S13 is R (red).

  When it is determined that the color component having the highest brightness in the captured image is R (red) (S15: YES), the process proceeds to S16. On the other hand, when it is determined that the color component having the highest brightness in the captured image is other than R (red) (S15: NO), the process proceeds to S17.

  In S <b> 16, the CPU 31 transmits a signal to the projector 4, and the brightness of the projected video increases for G (green) and B (blue), which are color components other than the color component determined to have the highest brightness in the captured image. Adjust as follows. Specifically, for G (green) and B (blue), the brightness of the projected image is set to a maximum value. As a result, even when the illuminance around the position where the virtual image is generated is particularly high, the occupant can display the virtual image with a color component that easily distinguishes the virtual image from the superimposed background (green and blue are strong colors). It is possible to clearly see the virtual image generated in (1). Thereafter, the process proceeds to S20.

  In S17, the CPU 31 determines whether or not the color component having the highest brightness in the captured image specified in S13 is G (green).

  When it is determined that the color component having the highest brightness in the captured image is G (green) (S17: YES), the process proceeds to S18. On the other hand, when it is determined that the color component having the highest brightness in the captured image is not G (green), that is, B (blue) (S17: NO), the process proceeds to S19.

  In S <b> 18, the CPU 31 transmits a signal to the projector 4, and the brightness of the projected image increases for R (red) and B (blue), which are color components other than the color component determined to have the highest brightness in the captured image. Adjust as follows. Specifically, for R (red) and B (blue), the brightness of the projected image is set to a maximum value. As a result, even when the illuminance around the position where the virtual image is generated is particularly high, the occupant can display the virtual image with a color component that easily distinguishes the virtual image from the superimposed background (red and blue are strong colors). It is possible to clearly see the virtual image generated in (1). Thereafter, the process proceeds to S20.

  On the other hand, in S <b> 19, the CPU 31 transmits a signal to the projector 4, and the brightness of the projected video is R (red) and G (green) that are color components other than the color component determined to have the highest brightness in the captured image. Adjust to be higher. Specifically, for R (red) and G (green), the brightness of the projected image is set to a maximum value. As a result, even when the illuminance around the position where the virtual image is generated is particularly high, the occupant can display the virtual image with a color component that easily distinguishes the virtual image from the superimposed background (red and green are strong colors). It is possible to clearly see the virtual image generated in (1). Thereafter, the process proceeds to S20.

  In S20, the CPU 31 transmits a signal to the projector 4, the luminance of the light source 19 set to the upper limit value, and the brightness of the color component set in S16, S18, S19, and the first screen 20 and the projector 4 The projection of the video onto the second screen 21 is started. Since details are the same as S6, explanation is omitted.

  Thereafter, in S21, the CPU 31 determines whether or not a condition for terminating the display of the virtual image is satisfied.

  And when it determines with satisfy | filling the conditions which complete | finish the display of a virtual image (S21: YES), the production | generation of the virtual image by HUD1 is complete | finished. On the other hand, when it is determined that the condition for ending the display of the virtual image is not satisfied (S21: NO), the process returns to S2, and the virtual image is continuously generated by the HUD1. If the surrounding environment (illuminance or the like) changes after the display of the virtual image is changed, display correction of the virtual image being displayed is performed in accordance with the processing after S2.

  On the other hand, in S22, the CPU 31 transmits a signal to the projector 4 and binarizes the brightness of each color component representing each pixel constituting the projection image, thereby forming the projection image only with white or black pixels. Adjust to That is, a pixel having the maximum brightness of R (red), G (green), and B (blue) is white, and the brightness of R (red), G (green), and B (blue) is all minimum. The resulting pixel will be black. Note that, for example, a discrimination / identification method, a mode method, a Kittler method, a 3σ method, a p-tile method, or the like is used to determine a threshold value when performing binarization processing.

  Thereafter, in S20, the CPU 31 transmits a signal to the projector 4, and the first screen 20 by the projector 4 has the brightness of the light source 19 set to the upper limit value and the brightness of the color component binarized in S22. And the projection of the image | video on the 2nd screen 21 is started. As a result, as shown in FIG. 17, the first virtual image 8A and the second virtual image 8B are displayed with two gradations of white or black. Therefore, even when the illuminance around the position where the virtual image is generated is particularly high and the virtual image cannot be visually recognized by the occupant 7 by normal display correction, the virtual image is displayed in two gradations of white and black that are most easily identified by the occupant. The virtual image generated by the occupant can be appropriately viewed. Thereafter, the process proceeds to S21, where it is determined whether or not the condition for ending the display of the virtual image is satisfied as described above.

  As described above in detail, according to the HUD 1 according to the present embodiment, the projector 4 projects images on the first screen 20 and the second screen 21 via the first projection lens 16 and the second projection lens 17, respectively. The virtual image of the image visually recognized by the vehicle occupant 7 is generated by reflecting the image projected on the first screen 20 and the second screen 21 to the front window 6 of the vehicle 2 and causing the vehicle occupant 7 to visually recognize the image. Further, when generating a virtual image, the surrounding environment of the position where the virtual image is generated is acquired (S2, S9 to S13), and based on the acquired surrounding environment, the brightness of the light source 19 of the projector 4 and the image to be projected are obtained. Since the brightness of each color component (R (red), G (green), B (blue)) is adjusted (S5, S8, S16, S18, S19, S22), a virtual image is displayed in a wider range than before. Correction can be performed. As a result, it becomes possible for the user to clearly see the virtual image regardless of the surrounding environment. In particular, even if the position where the virtual image is generated is in a very bright state due to the strong reflection of the sun, the generated virtual image can be appropriately viewed by the user.

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, when the illuminance detected by the illuminance sensor 50 is equal to or higher than the reference illuminance (S3: NO) without performing the processing of S14 to S19 in the display correction processing program (FIG. 12) implemented in the present embodiment. May be configured to always perform the process of S22. Or it is good also as a structure which always performs the process of S15-S19, when the process of S14 and S22 is not implemented and the illumination intensity detected with the illumination intensity sensor 50 is more than a reference | standard illumination intensity (S3: NO).

  Further, in S16, S18, and S19 of the display correction processing program (FIG. 12) of the present embodiment, the brightness of the projected video is maximized for the color components other than the color component determined to have the highest brightness in the captured image. However, it is not always necessary to increase the maximum value. For example, it may be configured to be 50% higher.

  In this embodiment, the movable range of the second screen is set so that the generation distance L2 is displaced between 2.5 m and 20 m, but the lower limit and the upper limit of the generation distance L2 can be changed as appropriate. It is.

  In the present embodiment, only the second screen 21 is configured to be movable in the front-rear direction along the optical path. However, the first screen 20 may be configured to be movable. Similarly, the first projection lens 16 may be configured to be movable. On the other hand, both the first screen 20 and the second screen 21 may be fixed screens whose positions are fixed. Further, only the second screen 21 may be configured to be movable in the front-rear direction along the optical path, and the position of the second projection lens 17 may be fixed.

  In this embodiment, the screen is composed of two screens, a first screen 20 and a second screen 21, and the lens of the projector 4 is composed of two lenses, a first projection lens 16 and a second projection lens 17. However, the number of screens and lenses may be one or three or more. Further, as the light source of the projector 4, a lamp or a laser may be used in addition to the LED.

  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 the 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 luminance of the light source A light source adjusting means for adjusting the brightness, an RGB adjusting means for adjusting the brightness of each element of red, green, and blue representing each pixel constituting the video, and an environment for acquiring a surrounding environment at a position where the virtual image is generated Acquisition means, and the light source adjustment means and the RGB adjustment means adjust the luminance of the light source and the brightness of each element based on the surrounding environment acquired by the environment acquisition means. And
According to the head-up display device having the above configuration, the brightness of each element of red, green, and blue that represents each pixel constituting the video in addition to the luminance of the light source based on the surrounding environment where the virtual image is generated Therefore, display correction of a virtual image can be performed in a wider range than in the past. As a result, it becomes possible for the user to clearly see the virtual image regardless of the surrounding environment. In particular, even if the position where the virtual image is generated is in a very bright state due to the strong reflection of the sun, the generated virtual image can be appropriately viewed by the user.

The second configuration is as follows.
The environment acquisition unit acquires illuminance as the surrounding environment, and the light source adjustment unit adjusts the luminance of the light source to be higher as the illuminance acquired by the environment acquisition unit is higher. .
According to the head-up display device having the above configuration, even when the illuminance around the position where the virtual image is generated is high, the virtual image can be displayed with luminance according to the illuminance, and the generated virtual image is clear to the user. Can be visually recognized.

The third configuration is as follows.
The light source adjustment unit adjusts the luminance of the light source to be higher as the illuminance acquired by the environment acquisition unit is higher until the luminance of the light source reaches an upper limit value, and is acquired by the environment acquisition unit. If the illuminance is equal to or higher than the reference illuminance that is the illuminance at which the luminance of the light source reaches the upper limit value, the luminance of the light source is adjusted to become the upper limit value, and the RGB adjustment unit is If the illuminance acquired by the above is less than the reference illuminance, the brightness of each element is not adjusted, and if the illuminance acquired by the environment acquisition means is greater than or equal to the reference illuminance, acquired by the environment acquisition means The brightness of each element is adjusted based on the surrounding environment.
According to the head-up display device having the above-described configuration, even when the illuminance around the position where the virtual image is generated is particularly high, the brightness of each element of red, green, and blue representing each pixel constituting the video can be adjusted. Thus, it becomes possible to correct the display color of the virtual image so that the user can easily identify the virtual image from the superimposed background. As a result, the virtual image generated by the user can be clearly seen.

The fourth configuration is as follows.
For the captured image obtained by capturing the position at which the virtual image is generated from the user side who visually recognizes the virtual image as the surrounding environment, each of the environment acquisition means represents each of red, green, and blue representing each pixel constituting the captured image. The brightness of the element is acquired, and the RGB adjustment unit specifies the element having the highest brightness in the captured image based on the brightness of each element acquired by the environment acquisition unit, and determines each pixel constituting the video. Of the elements to be expressed, the two color elements other than the specified elements are adjusted to have higher brightness.
According to the head-up display device having the above configuration, even when the illuminance around the position where the virtual image is generated is particularly high, the virtual image can be displayed with a color component that makes it easy to identify the virtual image from the background on which the user is superimposed. It is possible to clearly see the virtual image generated in (1).

The fifth configuration is as follows.
The environment acquisition unit acquires the luminance of a captured image obtained by capturing the position where the virtual image is generated from the user side who visually recognizes the virtual image as the surrounding environment, and the RGB adjustment unit is acquired by the environment acquisition unit When the brightness of the captured image is greater than or equal to a threshold value, the brightness of each element representing each pixel constituting the video is binarized to adjust the video to be configured with white or black pixels. It is characterized by.
According to the head-up display device having the above configuration, the illuminance around the position where the virtual image is generated is particularly high, and even when the virtual image cannot be visually recognized by the user with normal display correction, A virtual image can be displayed with two gradations of black, and the generated virtual image can be visually recognized by the user.

DESCRIPTION OF SYMBOLS 1 Head up display apparatus 2 Vehicle 3 Dashboard 4 Projector 5 Screen 6 Front window 7 Crew 8 Virtual image 16 1st projection lens 17 2nd projection lens 18 Lens drive motor 20 1st screen 21 2nd screen 24 Screen front and rear drive motor 25 screen Vertical drive motor 31 CPU
32 RAM
33 ROM
34 Flash memory 50 Illuminance sensor

Claims (6)

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;
Light source adjusting means for adjusting the luminance of the light source;
RGB adjustment means for adjusting the brightness of each element of red, green and blue representing each pixel constituting the video;
Environment acquisition means for acquiring the surrounding environment of the position where the virtual image is generated,
The head-up display device, wherein the light source adjustment unit and the RGB adjustment unit adjust the luminance of the light source and the brightness of each element based on the surrounding environment acquired by the environment acquisition unit. The environment acquisition means acquires illuminance as the surrounding environment,
The head-up display device according to claim 1, wherein the light source adjustment unit adjusts the luminance of the light source to be higher as the illuminance acquired by the environment acquisition unit is higher. The light source adjusting means is
Until the luminance of the light source reaches the upper limit, the higher the illuminance acquired by the environment acquisition means, the higher the luminance of the light source,
If the illuminance acquired by the environment acquisition means is equal to or higher than the reference illuminance that is the illuminance at which the luminance of the light source reaches the upper limit, adjust the luminance of the light source to be the upper limit,
The RGB adjusting means includes
When the illuminance acquired by the environment acquisition means is less than the reference illuminance, without adjusting the brightness of each element,
The brightness of each element is adjusted based on the surrounding environment acquired by the environment acquisition unit when the illuminance acquired by the environment acquisition unit is greater than or equal to the reference illuminance. Head-up display device. For the captured image obtained by capturing the position at which the virtual image is generated from the user side who visually recognizes the virtual image as the surrounding environment, each of the environment acquisition means represents each of red, green, and blue representing each pixel constituting the captured image. Get the brightness of the element,
The RGB adjusting means includes
Based on the brightness of each element acquired by the environment acquisition means, identify the element with the highest brightness in the captured image,
4. The device according to claim 1, wherein among the elements representing each pixel constituting the video, adjustment is performed so that the brightness of the two color elements other than the specified element is higher. A head-up display device according to claim 1. The environment acquisition means acquires the brightness of a captured image obtained by capturing the position where the virtual image is generated from the user side who visually recognizes the virtual image as the surrounding environment,
The RGB adjusting means includes
When the brightness of the captured image acquired by the environment acquisition unit is greater than or equal to a threshold value, the brightness of each element representing each pixel constituting the image is binarized to make the image a white or black pixel The head-up display device according to any one of claims 1 to 3, wherein the head-up display device is adjusted to be configured as follows. The environment acquisition means acquires the brightness of each element of red, green, and blue representing each pixel constituting the captured image,
The RGB adjusting means includes
When the brightness of the captured image acquired by the environment acquisition unit is less than a threshold, based on the brightness of each element acquired by the environment acquisition unit, identify the element with the highest brightness in the captured image,
6. The head-up display according to claim 5, wherein among the elements representing each pixel constituting the video, adjustment is performed so that the brightness of the two color elements other than the specified element is higher. apparatus.

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