Display device for vehicle

Abstract

The invention provides a display device for a vehicle. When the display is switched between the inner side and the outer side of a vehicle, the visibility of an observer is improved by adjusting the light quantity of each display. The present invention is a vehicle display device (1) in which a virtual image (VI) and a real image (RI) of a display image represented by display light (L) are viewed by emitting the display light (L) from an opening (18) toward a windshield (WS), the vehicle display device (1) comprising: a display unit (12) which is provided with a display element (121), transmits light emitted from a light source (11), and displays the display image; a reflection unit (13) that reflects, toward a windshield (WS), light indicating a display image displayed on the display unit (12); and a control unit (15). The control unit (15) executes a light quantity control process for controlling the light quantity of the light source (11) such that a predetermined brightness difference exists between a real image display brightness setting when the real image (RI) is viewed and a virtual image display brightness setting when the virtual image (VI) is viewed.

Description

Technical Field

[0001] The present invention relates to a vehicle display device that performs a required display for an observer. Background Art

[0002] Conventionally, for example, an electronic device described in Patent Document 1 is known. The electronic device includes a cluster display unit mounted on an instrument panel and a head-up display (HUD), determines the driving state of a vehicle, and adjusts the focal length of the HUD according to the determination result so that the virtual image position of a projected image is near the cluster display unit or in front of a windshield.

[0003] Prior Art Documents

[0004] Patent Documents

[0005] Patent Document 1: Japanese Patent No. 6516642 Gazette Summary of the Invention

[0006] Problems to be Solved by the Invention

[0007] However, in the conventional electronic device, since the display position of the virtual image can be switched between inside and outside the vehicle, when presented together with ambient light in an outside-vehicle display, the visual effect is different from that in an inside-vehicle display. Therefore, when switching the display position from one display to another for viewing (or viewing simultaneously), there may be a problem of glare due to the brightness difference.

[0008] Therefore, the present invention has been completed in view of the above problems, and an object thereof is to provide a vehicle display device that improves the visibility for an observer by adjusting the light amount of each display when switching the display between the inside and outside of the vehicle.

[0009] Means for Solving the Problems

[0010] The present invention is a vehicle display device 1, characterized in that it is provided in a vehicle C including a seat on which an occupant DR is seated and a light-transmitting member WS, and by emitting display lights L1, L2 from a light-emitting port 17 to the light-transmitting member WS, a virtual image VI and a real image RI of a display image represented by the display lights L1, L2 are seen, and includes: a display unit 12 having a display element that transmits the light emitted from a light source 11 and displays the display image; a reflection unit 13 that reflects the light representing the display image displayed on the display unit 12 to the light-transmitting member WS; and a control unit 15; and the control unit 15 performs light amount control processing (S3, S4, S6, and S7) to control the light amount of the light source 11 such that there is a specified brightness difference between a first display brightness setting when seeing the real image RI and a second display brightness setting when seeing the virtual image VI.

[0011] Effect of the Invention

[0012] According to the present invention, by adjusting the light amount of the light source, the vehicle occupants can view the real image and the virtual image with an appropriate brightness difference. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 It is a diagram showing the configuration when the vehicle display device according to the first embodiment of the present invention generates a virtual image.

[0014] Figure 2 It is a diagram showing the configuration when the vehicle display device according to the first embodiment of the present invention generates a real image.

[0015] Figure 3 It is a schematic diagram showing the structure of the light source and the display unit of the HUD device in the vehicle display device according to the first embodiment of the present invention.

[0016] Figure 4 It is a functional block diagram for explaining the configuration of the control unit of the vehicle display device according to the first embodiment of the present invention.

[0017] Figure 5 It is a diagram showing the brightness setting with respect to the ambient light during the day.

[0018] Figure 6 It is a diagram showing the brightness setting with respect to the ambient light in the evening.

[0019] Figure 7 It is a diagram showing the brightness setting with respect to the ambient light at night.

[0020] Figure 8 It is a diagram showing an example of the brightness change when the vehicle display device according to the first embodiment of the present invention switches between real image display and virtual image display.

[0021] Figure 9 It is a diagram showing an example of the brightness change pattern when switching between real image display and virtual image display during the day or in the evening.

[0022] Figure 10 It is a diagram showing an example of the brightness change pattern when switching between real image display and virtual image display at night.

[0023] Figure 11 It is a flowchart showing the operation of the control unit in the vehicle display device according to the first embodiment of the present invention.

[0024] Figure 12 It is a diagram showing the configuration of the vehicle display device according to the second embodiment of the present invention.

[0025] REFERENCE SIGNS LIST

[0026] C: Vehicle; DR: Driver; F: Optical focus; F1: First optical focus; F2: Second optical focus; L(L1, L2): Display light; L11: First display light; L22: Second display light; VI: Virtual image; RI: Real image; R1, R2: Radius of curvature; WS: Windshield; 1: Vehicle display device; 2: HUD device; 3: Setting unit; 11: Light source; 11a: First light source; 11b: Second light source; 12: Display unit; 12a: First display unit; 12b: Second display unit; 13: Reflection unit; 15: Control unit; 16: Housing; 17: Opening; 18: Cover glass; 21: Display control unit; 22: Display unit drive unit; 30: Various devices; 51: Operation unit; 52: Display brightness setting information; 53: External information; 54: Light quantity control unit; 54a: Real image brightness adjustment unit; 54b: Virtual image brightness adjustment unit; 55: Switching control unit; 56: Display control unit; 121: Display element; 122: Switching element; 131: First mirror; 132: Second mirror; 133: Third mirror; 1310: First correction mirror; 1320: Second correction mirror; 1330: Concave mirror. Detailed implementation mode

[0027] (The first implementation mode of the present invention)

[0028] Use Figures 1 to 11 The vehicle display device of the present embodiment will be described. Figure 1 It is a diagram showing the configuration when the vehicle display device of the present embodiment generates a virtual image, Figure 2 It is a diagram showing the configuration when the vehicle display device of the present embodiment generates a real image.

[0029] Figure 1 And Figure 2 In, the vehicle display device 1 includes a head-up display device (hereinafter referred to as HUD device) 2 and a setting unit 3 that stores setting information for controlling the HUD device 2. The HUD device 2 includes a light source 11, a display unit 12, a reflection unit 13, and a control unit 15, and they are housed in a housing 16. The light source 11 is composed of, for example, a light-emitting diode that emits light in the visible wavelength region and is mounted on a wiring board, and emits white light. The display unit 12 generates an image using the light incident from the light source 11 and switches the polarization of the emitted light for display between a first polarization and a second polarization that are different from each other. The reflection unit 13 reflects the display light L representing the display image displayed on the display unit 12 ( Figure 1 In the case of, it is the display light L1 representing the display image of the virtual image VI, Figure 2In the case of reflecting the display light L2 for the display image representing the real image RI) toward the windshield WS (light-transmitting member), the control unit 15 controls the display content of the display unit 12, switches the control of the first polarization and the second polarization, and adjusts the light amount of the light emitted from the light source 11 to perform brightness control. An opening 17 (light-emitting port) for emitting the display light L is provided in the housing 16, and a cover glass 18 for protecting the interior is disposed at the opening 17. The windshield WS is an example of a light-projecting member, and the opening 17 is an example of a light-emitting port.

[0030] The HUD device 2 is disposed below the windshield WS of the vehicle C (for example, inside the instrument panel), emits display light L (L1, L2), and projects it onto the windshield WS. The display light L is generated by the light source 11 and the display unit 12 inside the HUD device 2. The display light L emitted from the display unit 12 passes through the reflection unit 13 and exits through the cover glass 18 from the opening 17 of the housing 16. The driver DR (occupant) of the vehicle C can see a virtual image VI as shown Figure 1 on the far side of the windshield WS by observing the display light L reflected by the windshield WS, and can see a real image RI as shown Figure 2 in the near front side of the windshield WS.

[0031] Regarding Figure 1 the virtual image VI shown, for example, vehicle information such as the speed and engine speed of the vehicle C, route navigation display such as turn-by-turn navigation or a map, warning displays such as a blind spot indicator and a speeding warning, etc., which are highly necessary for reminding the driver DR, are displayed on the opposite side of the windshield WS in the driver DR's view. In addition, regarding Figure 2 the real image RI shown, for example, entertainment content, an assistant or agent supporting the driver DR, and characters presenting these are displayed in the near front side of the windshield WS in the driver DR's view. Through these displays, a driving environment that reduces the need for eye movement and eye focus adjustment can be provided. In addition to the characters or icons representing this information, the virtual image VI and the real image RI also include a background part, which, when viewed from the planar view of the driver DR, is, for example, approximately rectangular.

[0032] Here, the configurations of the light source 11 and the display unit 12 will be described. Figure 3 is a schematic diagram showing the structures of the light source 11 and the display unit 12 of the HUD device 2 in the vehicle display device 1 of the present embodiment. As Figure 3As shown, a display unit 12 is provided on the light path side closer to the light exit than the light source 11. The display unit 12 includes, for example, a thin film transistor (TFT) type display element 121 and a switching element 122. The switching element 122 is provided on the light path side closer to the light exit than the display element 121, and switches the polarization of the emitted display light L between a first polarization and a second polarization that are different from each other.

[0033] In addition, for example, the first polarization can be set as S polarization and the second polarization can be set as P polarization, or vice versa. Furthermore, it is not limited to S polarization and P polarization, as long as the polarization angles of the first polarization and the second polarization are in different states. For example, the difference in polarization angles is preferably at least 22.5 degrees or more.

[0034] In addition, as Figure 1 and Figure 2 shown, in order to deal with stray light (light leaking from the light source 11) and external light (light entering from the outside), the display unit 12 excludes them from the light path of the display light L, and is preferably arranged obliquely with respect to the axial direction of the light rays of the display light L.

[0035] The light source 11 is connected to the real image brightness adjustment unit 54a and the virtual image brightness adjustment unit 54b described below in Figure 4 to adjust the light amount so that there is a specified brightness difference between the real image display brightness setting value (first display brightness setting) when the driver DR sees the real image RI and the virtual image display brightness setting value (second display brightness setting) when seeing the virtual image VI. The display element 121 forms light representing a pattern of an arbitrary shape according to a signal sent from the control unit 15. In addition, the switching element 122 extracts only specific polarizations from the light rays emitted from the display element 121, specifically, the light rays as the first polarization and the second polarization, and performs a switching process between them. The switching element 122 is connected to the switching control unit 22 described below in Figure 4 and switches the polarization according to a signal sent from the switching control unit 22.

[0036] In addition, the polarization switching by the switching element 122 can be performed by electrical processing, or by arranging a polarizing plate or a wavelength plate on the light exit side of the display element 121 and physically rotating it around the optical axis direction by a specified angle with respect to the central axis, thereby performing polarization switching. In either case, the polarization switching can be performed under the control of the switching control unit 22.

[0037] Figure 1 and Figure 2In the figure, the reflection unit 13 includes a first mirror 131, a second mirror 132, and a third mirror 133 that are formed of mirrors having a concave shape. The first mirror 131 reflects the display light L1 (first light ray) that is the first polarization and transmits the display light L2 (second light ray) that is the second polarization. The second mirror 132 reflects the display light L2 (second light ray) that passes through the first mirror 131. The respective display lights L1 and L2 reflected by the first mirror 131 and the second mirror 132 are guided to the third mirror 133, and after being reflected by the third mirror 133, are emitted to the windshield WS, so that the driver DR can see the respective display images. The display light L1 is an example of the first light ray, and the display light L2 is an example of the second light ray.

[0038] In addition, although innumerable light rays are originally emitted from the display unit 12, for simplicity of explanation, the light that is emitted from the center of the display unit 12 and passes through the center of the eye box is called a representative light ray and is denoted by the symbol L. In addition, Figure 1 and Figure 2 , and as will be described later Figure 12 in the figure, the solid line represents the representative light ray emitted from the center of the display unit 12, the one-dot chain line represents the light ray emitted from the upper end portion of the display unit 12, and the double-dot chain line represents the light ray emitted from the lower end portion of the display unit 12.

[0039] In addition, as Figure 2 shown, since the first mirror 131 is a mirror that transmits the display light L2, the display light L2 reflected by the second mirror 132 will of course also be transmitted from the back side where the second mirror 132 is located to the front side. That is to say, as Figure 2 shown, the display light L2 that passes through the first mirror 131 is reflected by the second mirror 132, passes through the first mirror 131 again, and is guided to the third mirror 133. Thereby, the second mirror 132 can be arranged closer to the back side of the first mirror 131, so that the enlargement of the housing 16 can be prevented.

[0040] Here, for example, the first polarization is set as S polarization (S polarization with respect to the first mirror 131), the second polarization is set as P polarization (P polarization with respect to the first mirror 131), the first mirror 131 is made into a mirror that reflects the light that is S polarization with respect to the first mirror 131 and transmits the light that is P polarization, and the second mirror 132 is made into a mirror that reflects the light that is P polarization with respect to the first mirror 131 and transmits the light that is S polarization. In the case of this configuration, the display light L1 that is S polarization is reflected by the first mirror 131 and is guided to the third mirror 133. The display light L2 that is P polarization passes through the first mirror 131, is reflected by the second mirror 132, and is guided to the third mirror 133. By setting the configuration of the reflection unit 13 and the polarizations of the display lights L1 and L2 in this way, the respective display lights L1 and L2 can generate different display images.

[0041] Specifically explain Figure 1The display image represented by the display light L1 in Figure 2 and the display image represented by the display light L2 in Figure 2 As shown in Figure 2 , the second mirror 132 is a mirror with a concave shape and has the following radius of curvature: when the second mirror 132, the third mirror 133, and the windshield WS are regarded as an optical system, the position of the display unit 12 becomes the second state outside the focal length of the optical system (front stage side with respect to the display light L). Therefore, when the light of the second polarized light is emitted, the light reflected by the second mirror 132, the third mirror 133, and the windshield WS becomes a real image RI and is seen by the driver DR.

[0042] In addition, as Figure 1 shown, the first mirror 131 is also a mirror with a concave shape, but has a radius of curvature R1 (R1 > R2) larger than the radius of curvature R2 of the second mirror 132, and has the following radius of curvature: when the first mirror 131, the third mirror 133, and the windshield WS are regarded as an optical system, the position of the display unit 12 becomes the first state inside the focal length of the optical system (rear stage side with respect to the display light L). This is because when the radius of curvature of a mirror with a concave shape is large, the focal length is far from the mirror, and when the radius of curvature is small, the focal length is close to the mirror. Therefore, the radius of curvature of the first mirror 131 with a farther focal length is larger. Thus, when the light of the first polarized light is emitted, the light reflected by the first mirror 131, the third mirror 133, and the windshield WS becomes a virtual image VI and is seen by the driver DR. In addition, Figure 1 and Figure 2 in Figure 2 , F represents the optical focus.

[0043] That is to say, for example, when it is desired to see the virtual image VI on the far side of the windshield WS from the driver DR's perspective, the switching element 122 of the display unit 12 switches the display light L to the display light L1 as the first polarized light and emits it. Through the imaging optical system composed of the first mirror 131, the third mirror 133, and the windshield WS, the display image represented by the display light L1 is displayed on the windshield WS. In addition, for example, when it is desired to see the real image RI in front of the windshield WS from the driver DR's perspective, the switching element 122 of the display unit 12 switches the display light L to the display light L2 as the second polarized light and emits it. Through the imaging optical system composed of the second mirror 132, the third mirror 133, and the windshield WS, the display image represented by the display light L2 is displayed on the windshield WS.

[0044] In addition, Figure 1 and Figure 2In [the description], the first mirror 131 is described as a mirror having a concave shape. However, when the first mirror 131, the third mirror 133, and the windshield WS are regarded as an optical system, as long as the position of the display unit 12 satisfies the condition of being inside the focal length of the optical system (on the rear stage side with respect to the display light L), it may also be a mirror having a planar shape or a convex shape.

[0045] In addition, Figure 1 and Figure 2 in [the description], the third mirror 133 is described as a mirror having a concave shape. However, it may also be a mirror having a planar shape or a convex shape. Since the display lights L1 and L2 are irradiated through the same third mirror 133 both when the virtual image VI is displayed and when the real image RI is displayed, it may also be a shape without magnification.

[0046] The control unit 15 at least controls the display content of the display unit 12, switches the control of the first polarization and the second polarization, and performs brightness control by adjusting the light quantity of the light emitted from the light source 11. Figure 4 is a functional block diagram for explaining the configuration of the control unit 15 of the vehicle display device 1 of the present embodiment. In addition, Figure 4 in [the description], only the configuration directly related to the processing of the control unit 15 is described, and the description of other well-known configurations is omitted.

[0047] Figure 4 In [the description], the HUD device 2 includes the control unit 15, the light source 11, the display unit 12, and the reflection unit 13 shown above. The control unit 15 includes a light quantity control unit 54 that controls the light quantity of the light source 11 based on the operation information from the operation unit 51 that switches the driving mode of the vehicle C (for example, the autonomous driving mode / the manual driving mode), the display brightness setting information 52 related to the brightness of the virtual image VI and the real image RI preset by the setting unit 3, and the external information 53 indicating the surrounding environment of the vehicle C. In addition, the control unit 15 includes a switching control unit 55 that switches the display light L emitted from the display unit 12 to the first polarization or the second polarization (that is, switches between the display state of the virtual image VI and the display state of the real image RI) based on the operation information from the operation unit 51. Further, the control unit 15 includes a display control unit 56 that issues a command to the display unit 12 to generate light representing a graphic of an arbitrary shape, for example, based on information transmitted from various devices 30 such as a vehicle speed sensor, a navigation device, a radar (RADAR, Radio Detecting and Ranging), and a lidar (LiDAR, Light Detection and Ranging, or Laser Imaging Detection and Ranging).

[0048] The driving modes of vehicle C include an automatic driving mode and a manual driving mode. For example, during the automatic driving mode, a real image RI is displayed in front of the windshield WS in the driver DR's field of view (inside the vehicle), and during the manual driving mode, a virtual image VI is displayed on the far side of the windshield WS in the driver DR's field of view (outside the vehicle). That is to say, when the driving mode is switched from the automatic driving mode to the manual driving mode by operating unit 51, switching control unit 55 switches the display light L emitted by display unit 12 from the light of the second polarization to the light of the first polarization. Conversely, when the driving mode is switched from the manual driving mode to the automatic driving mode by operating unit 51, switching control unit 55 switches the display light L emitted by display unit 12 from the light of the first polarization to the light of the second polarization.

[0049] In addition, in addition to the switching of the driving mode, for example, the polarization state of the display light L can also be switched according to the start / stop (ON / OFF) of adaptive cruise control (ACC). When the ACC function is turned on, switching control unit 55 can switch the display light L emitted by display unit 12 from the light of the first polarization to the light of the second polarization, and when the ACC function is turned off, the display light L can be switched from the light of the second polarization to the light of the first polarization.

[0050] In the switching process of switching control unit 55, when the virtual image VI is displayed together with the ambient light of vehicle C (hereinafter referred to as ambient light), the visual effect is different from that of displaying the real image RI inside the vehicle. When the position of the displayed image being viewed is switched between the display of the virtual image VI and the display of the real image RI, if they are both displayed at the same brightness, driver DR may feel the brightness difference between the ambient light and the interior light, making driver DR feel that the displayed image is dazzling. This is particularly obvious when viewing the displayed image and the scenery within the peripheral field of view of the displayed image at the same time. Therefore, by adjusting the brightness of the virtual image VI and the real image RI through light quantity control unit 54, this problem can be solved.

[0051] Hereinafter, the brightness setting corresponding to the ambient light will be specifically described. Figure 5 is a diagram showing the brightness setting for the ambient light during the day, Figure 6 is a diagram showing the brightness setting for the ambient light at dusk, Figure 7 is a diagram showing the brightness setting for the ambient light at night. For the day, as Figure 5 shown, the ambient light outside the vehicle is bright, and the interior of the vehicle is in a state equivalent to or slightly darker than it. At this time, if the virtual image VI and the real image RI are displayed at the same brightness, driver DR will feel that the real image RI is dazzling. Therefore, the brightness of the virtual image VI presented together with the ambient light outside the vehicle is set higher, and the brightness of the real image RI presented inside the vehicle is set lower.

[0052] For evening, as Figure 6 shown, the ambient light outside the vehicle is still relatively bright, while the brightness inside the vehicle is in a relatively dark state. At this time, if the virtual image VI and the real image RI are displayed at the same brightness, similar to the situation of Figure 5 , the driver DR will feel that the real image RI is dazzling. Therefore, the brightness of the virtual image VI presented together with the ambient light outside the vehicle is set to be relatively high, and the brightness of the real image RI presented inside the vehicle is set to be relatively low.

[0053] For night, as Figure 7 shown, the ambient light outside the vehicle is relatively dark, while the inside of the vehicle appears relatively bright due to the vehicle interior lights. At this time, if the virtual image VI and the real image RI are displayed at the same brightness, the driver DR will feel that the virtual image VI is dazzling. Therefore, the brightness of the virtual image VI presented together with the ambient light outside the vehicle is set to be relatively low, and the brightness of the real image RI presented inside the vehicle is set to be relatively high.

[0054] That is to say, appropriate brightness is set for each scenario according to the ambient light outside and inside the vehicle. For the setting of the ambient light outside and inside the vehicle, for example, it can be manually input by the driver DR, or it can be set based on the information of the headlight on / off of the vehicle C, or it can be set based on the illuminance information of the external light detected by the illuminance sensor provided on the vehicle C. Specifically, for example, when the headlight is not lit, it is regarded as daytime or evening, and the setting of the daytime or evening state is applied. When the headlight is lit, it is regarded as night, and the setting of the night state is applied. In addition, when the illuminance sensor provided on the vehicle C detects a brightness above a specified illuminance, it is regarded as daytime or evening, and the setting of the daytime or evening state is applied. When the detected brightness is lower than the specified illuminance, it is regarded as night, and the setting of the night state is applied.

[0055] The brightness setting information corresponding to the ambient light outside and inside the vehicle is pre-recorded in Figure 4 the display brightness setting information 52 shown. In the display brightness setting information 52, specifically, as Figures 5 to 7 shown, the real image display brightness setting value (first display brightness setting) when viewing the real image RI and the virtual image display brightness setting value (second display brightness setting) when viewing the virtual image VI are recorded for each state of the ambient light outside and inside the vehicle. Moreover, Figure 4 the real image brightness adjustment unit 54a shown performs the process of adjusting the light quantity of the light source 11 when displaying the real image RI, so that the brightness of the real image RI reaches the real image display brightness setting value, and the virtual image brightness adjustment unit 54b performs the process of adjusting the light quantity of the light source 11 when displaying the virtual image VI, so that the brightness of the virtual image VI becomes the virtual image display brightness setting value. Finally, there is a specified brightness difference between the real image RI and the virtual image VI.

[0056] For example, Figure 5 in the case of daytime and Figure 6In the case of evening, the set value of the virtual image VI presented together with the ambient light outside the vehicle, that is, the virtual image display brightness set value, is set relatively high, and the set value of the real image RI presented inside the vehicle, that is, the real image display brightness set value, is set relatively low. In this state, when the driving mode of the vehicle C is switched from the manual driving mode to the autonomous driving mode, and thus it is necessary to switch from the display of the virtual image VI outside the vehicle to the display of the real image RI inside the vehicle, the real image brightness adjustment unit 54a of the light quantity control unit 54 adjusts the brightness of the real image RI to be relatively low (for example, 500 cd / m 2 or so) based on the real image display brightness set value. Conversely, when the driving mode of the vehicle C is switched from the autonomous driving mode to the manual driving mode, and thus it is necessary to switch from the display of the real image RI inside the vehicle to the display of the virtual image VI outside the vehicle, the virtual image brightness adjustment unit 54b of the light quantity control unit 54 adjusts the brightness of the virtual image VI to be relatively high (for example, 1000 cd / m 2 or so) based on the virtual image display brightness set value. In addition, the so-called high (low) brightness here means that in the relationship between the brightness of the virtual image VI and the brightness of the real image RI, the relatively higher one (the relatively brighter one) is called high brightness, and the relatively lower one (the relatively darker one) is called low brightness.

[0057] In addition, for example Figure 7 in the case of night, the set value of the virtual image VI presented together with the ambient light outside the vehicle, that is, the virtual image display brightness set value, is set relatively low, and the set value of the real image RI presented inside the vehicle, that is, the real image display brightness set value, is set relatively high. In this state, when the driving mode of the vehicle C is switched from the manual driving mode to the autonomous driving mode, and thus it is necessary to switch from the display of the virtual image VI outside the vehicle to the display of the real image RI inside the vehicle, the real image brightness adjustment unit 54a of the light quantity control unit 54 adjusts the brightness of the real image RI to be relatively high (for example, 1000 cd / m 2 or so) based on the real image display brightness set value. Conversely, when the driving mode of the vehicle C is switched from the autonomous driving mode to the manual driving mode, and thus it is necessary to switch from the display of the real image RI inside the vehicle to the display of the virtual image VI outside the vehicle, the virtual image brightness adjustment unit 54b of the light quantity control unit 54 adjusts the brightness of the virtual image VI to be relatively low (for example, 500 cd / m 2 or so).

[0058] Figure 8 is a diagram showing an example of the brightness change when the vehicle display device 1 of the present embodiment switches between the real image RI display and the virtual image VI display. Figure 8 (A) shows an example of the brightness change when switching from a display state with a relatively low brightness setting to a display state with a relatively high brightness setting, Figure 8 (B) shows an example of the brightness change when switching from a display state with a relatively high brightness setting to a display state with a relatively low brightness setting. Figure 8The trigger in [it] is, for example, a switching operation of the driving mode or ON / OFF switching information of the ACC.

[0059] In the above-described Figure 5 and Figure 6 in the daytime and evening cases, when switching from the virtual image VI display to the real image RI display, the brightness setting changes from a higher state to a lower state, so it becomes Figure 8 the brightness change shown in the parentheses of (B). Conversely, when switching from the real image RI display to the virtual image VI display, the brightness setting changes from a lower state to a higher state, so it becomes Figure 8 the brightness change shown in (A).

[0060] In the above-described Figure 7 in the night case, when switching from the virtual image VI display to the real image RI display, the brightness setting changes from a lower state to a higher state, so it becomes Figure 8 the brightness change shown in the parentheses of (A). Conversely, when switching from the real image RI display to the virtual image VI display, the brightness setting changes from a higher state to a lower state, so it becomes as Figure 8 shown in (B).

[0061] As described above, through the light quantity control unit 54, according to the states of the ambient light outside and inside the vehicle, the brightness adjustment when switching from the virtual image VI to the real image RI and the brightness adjustment when switching from the real image RI to the virtual image VI are performed. In the vehicle display device 1 of the present embodiment, by further controlling the brightness change mode, the driver DR can view the virtual image VI or the real image RI more comfortably. Specifically, when the real image brightness adjustment unit 54a and the virtual image brightness adjustment unit 54b adjust the light quantity of the light source 11, they respectively start from a brightness lower than the real image display brightness setting value or the virtual image display brightness setting value, that is, the transition brightness setting value, increase the brightness over time, and adjust the light quantity of the light source 11 in such a way that it becomes the real image display brightness setting value or the virtual image display brightness setting value.

[0062] Figure 9 is a diagram showing an example of the brightness change mode when switching between the real image RI display and the virtual image VI display in the daytime or evening. Figure 9 (A) is a diagram showing the brightness change mode when switching from the real image RI display to the virtual image VI display, Figure 9 (B) is a diagram showing the brightness change mode when switching from the virtual image VI display to the real image RI display.

[0063] Figure 9 The case of (A) shows the state of switching from the real image RI with a relatively low display brightness to a state such as Figure 5 and Figure 6Control of the state of the virtual image VI with a relatively high set virtual image display brightness setting value. After receiving a trigger, the virtual image brightness adjustment unit 54b adjusts the light amount of the light source 11 in such a way that it starts from the first transition brightness setting value, which is lower than the virtual image display brightness setting value, increases the brightness over time, and becomes the virtual image display brightness setting value.

[0064] Figure 9 (B) represents the control of the state of switching from the state of the virtual image VI with a relatively high display brightness to the state of displaying the real image RI with the real image display brightness setting value set relatively low as shown in Figure 5 and Figure 6 After receiving a trigger, the real image brightness adjustment unit 54a adjusts the light amount of the light source 11 in such a way that it starts from the second transition brightness setting value, which is lower than the real image display brightness setting value, increases the brightness over time, and becomes the real image display brightness setting value.

[0065] Figure 10 It is a diagram showing an example of the brightness change pattern when switching between the real image RI display and the virtual image VI display at night. Figure 10 (A) is a diagram showing the brightness change pattern when switching from the real image RI display to the virtual image VI display, Figure 10 (B) is a diagram showing the brightness change pattern when switching from the virtual image VI display to the real image RI display.

[0066] Figure 10 (A) represents the control of the state of switching from the state of the real image RI with a relatively high display brightness to the state of displaying the virtual image VI with the virtual image display brightness setting value set relatively low as shown in Figure 7 After receiving a trigger, the virtual image brightness adjustment unit 54b adjusts the light amount of the light source 11 in such a way that it starts from the second transition brightness setting value, which is lower than the virtual image display brightness setting value, increases the brightness over time, and becomes the virtual image display brightness setting value.

[0067] Figure 10 (B) represents the control of the state of switching from the state of the virtual image VI with a relatively low display brightness to the state of displaying the real image RI with the real image display brightness setting value set relatively high as shown in Figure 7 After receiving a trigger, the real image brightness adjustment unit 54a adjusts the light amount of the light source 11 in such a way that it starts from the first transition brightness setting value, which is lower than the real image display brightness setting value, increases the brightness over time, and becomes the real image display brightness setting value.

[0068] In addition, Figure 9 (A) and Figure 10(B), the first transition brightness setting value is set to a value between the real image display brightness setting value and the virtual image display brightness setting value. However, the first transition brightness setting value may also be set to the brightness value of the display light L before switching. That is to say, it may also be set to the brightness change mode as shown in Figure 8 (A).

[0069] In addition, in the block diagram of Figure 4 , a configuration in which the display brightness setting information 52 is stored in a setting unit 3 outside the HUD device 2 (for example, a storage unit such as a read-only memory (ROM) provided in the vehicle C) is described. However, the setting unit 3 may also be configured to be provided inside the HUD device 2.

[0070] Next, the operation of the control unit 15 when switching between the virtual image VI display and the real image RI display will be described. Figure 11 is a flowchart showing the operation of the control unit 15 in the vehicle display device 1 of the present embodiment. First, the control unit 15 acquires information related to the on / off state of, for example, the headlight as external information 53, and determines whether the current time is in a daytime or evening state or a nighttime state (S1). In addition, the process of S1 is not limited to the information related to the state of the headlight. As described above, the illuminance information of the external light detected by the illuminance sensor provided in the vehicle C may also be used.

[0071] When it is determined in S1 that it is daytime or evening, it is determined whether the switching of the display light L is from the real image RI display to the virtual image VI display or from the virtual image VI display to the real image RI display (S2). When it is the switching from the real image RI display to the virtual image VI display in S2, the virtual image brightness adjustment unit 54b of the light quantity control unit 54 adjusts the light quantity of the light source 11 in the Figure 9 (A) shown brightness value change mode (S3) (light quantity control process), and ends the process. When it is the switching from the virtual image VI display to the real image RI display in S2, the real image brightness adjustment unit 54a of the light quantity control unit 54 adjusts the light quantity of the light source 11 in the Figure 9 (B) shown brightness value change mode (S4) (light quantity control process), and ends the process.

[0072] When it is determined in S1 that it is nighttime, it is determined whether the switching of the display light L is from the real image RI display to the virtual image VI display or from the virtual image VI display to the real image RI display (S5). When it is the switching from the real image RI display to the virtual image VI display in S5, the virtual image brightness adjustment unit 54b of the light quantity control unit 54 adjusts the light quantity of the light source 11 in the Figure 10(A) The light intensity of the light source 11 is adjusted in a manner that changes the brightness value (S6) (light intensity control processing), and the processing is terminated. When the display of the virtual image VI is switched to the display of the real image RI in S5, the real image brightness adjustment unit 54a of the light intensity control unit 54 is switched to Figure 10 The light amount of the light source 11 is adjusted according to the change pattern of the brightness value shown in (B) (S7) (light amount control process), and the process is terminated.

[0073] As described above, the vehicle display device 1 of this embodiment is provided in a vehicle C including a seat on which a driver DR sits and a windshield WS. The vehicle display device 1 emits display light L from an opening 17 toward the windshield WS, thereby allowing a virtual image VI and a real image RI of a display image represented by the display light L to be seen. The vehicle display device 1 includes: a display unit 12 having a display element 121 that transmits light emitted by a light source 11 and displays a display image; a reflecting unit 13 that reflects light representing the display image displayed on the display unit 12 toward the windshield WS; and a control unit 15. The control unit 15 executes a light quantity control process ( Figure 11 S3, S4, S6 and S7), the light amount of the light source 11 is controlled in such a way that there is a specified brightness difference between the real image display brightness setting value when the real image RI is seen and the virtual image display brightness setting value when the virtual image VI is seen. Therefore, an appropriate brightness difference can be set between the brightness of the real image RI usually displayed on the inside of the vehicle and the brightness of the virtual image VI usually displayed on the outside of the vehicle, thereby avoiding visual discomfort or glare that may be caused when switching between the display of the real image RI and the display of the virtual image VI with the same brightness.

[0074] In addition, as needed, the control unit 15 of the vehicle display device 1 of this embodiment controls the light amount of the light source 11 in a manner such that the virtual image display brightness setting (the brightness of the virtual image VI displayed based on the virtual image display brightness setting value) becomes brighter than the real image display brightness setting (the brightness of the real image RI displayed based on the real image display brightness setting value) during the light amount control processing. Therefore, for example, during the day or in the evening, the brightness outside the vehicle is the same as or brighter than that inside the vehicle. In this case, if the real image RI and the virtual image VI are the same brightness, the driver DR will feel that the real image RI is dazzling. Therefore, by controlling the real image RI to be darker (in other words, making the virtual image VI brighter), the aforementioned glare or discomfort can be prevented.

[0075] In addition, as needed, in the light quantity control process, the control unit 15 of the vehicle display device 1 according to this embodiment controls the light quantity of the light source 11 such that the real image display brightness setting (the brightness of the real image RI display based on the real image display brightness setting value) is brighter than the virtual image display brightness setting (the brightness of the virtual image VI display based on the virtual image display brightness setting value). Therefore, for example, at night (when the interior light of the vehicle is on), the brightness inside the vehicle is brighter than that outside the vehicle. In this case, if the real image RI and the virtual image VI have the same brightness, the driver DR will feel that the virtual image VI is dazzling. Therefore, by controlling the virtual image VI to be darker (in other words, making the real image RI brighter), the above-mentioned dazzling or uncomfortable feeling can be prevented.

[0076] In addition, as needed, when the headlight provided on the vehicle C is turned off, or when the illuminance of the external light detected by the illuminance sensor provided on the vehicle C is equal to or higher than a specified value, the control unit 15 of the vehicle display device 1 according to this embodiment performs a light quantity control process of controlling the light quantity of the light source 11 such that the virtual image display brightness setting (the brightness of the virtual image VI display based on the virtual image display brightness setting value) is brighter than the real image display brightness setting (the brightness of the real image RI display based on the real image display brightness setting value). Therefore, by using the turning off of the headlight and the detected illuminance being equal to or higher than the specified value as a trigger, it is possible to accurately detect that it is daytime or evening, and thus the light quantity control process can be surely performed with high precision.

[0077] In addition, as needed, when the headlight provided on the vehicle C is turned on, or when the illuminance of the external light detected by the illuminance sensor provided on the vehicle C is less than the specified value, the control unit 15 of the vehicle display device 1 according to this embodiment performs a light quantity control process of controlling the light quantity of the light source 11 such that the real image display brightness setting (the brightness of the real image RI display based on the real image display brightness setting value) is brighter than the virtual image display brightness setting (the brightness of the virtual image VI display based on the virtual image display brightness setting value). Therefore, by using the turning on of the headlight and the detected illuminance being less than the specified value as a trigger, it is possible to accurately detect that it is night, and thus the light quantity control process can be surely performed with high precision.

[0078] In addition, as needed, when the control unit 15 of the vehicle display device 1 according to the present embodiment switches the brightness setting from the relatively darker side of the real image display brightness setting (brightness of the real image RI display based on the real image display brightness setting value) and the virtual image display brightness setting (brightness of the virtual image VI display based on the virtual image display brightness setting value) in the light quantity control process to the relatively brighter other side, after changing to the first transition brightness setting value that is darker than the brightness setting of the other side from one side's brightness setting, starting from the first transition brightness setting value, the light quantity of the light source 11 is controlled in such a way that the brightness increases with time to become the brightness setting of the other side. Therefore, when switching from a darker brightness setting to a brighter brightness setting, it does not suddenly switch to the brighter brightness, but instead transitively switches to a brightness slightly darker than the brighter brightness setting, and then slowly increases the brightness to change to the brighter brightness setting. Thus, it is possible to alleviate the discomfort of the driver DR caused by the brightness switch and reduce the burden on the eyes.

[0079] In addition, as needed, when the control unit 15 of the vehicle display device 1 according to the present embodiment switches the brightness setting from the relatively brighter other side of the real image display brightness setting (brightness of the real image RI display based on the real image display brightness setting value) and the virtual image display brightness setting (brightness of the virtual image VI display based on the virtual image display brightness setting value) in the light quantity control process to the relatively darker side, after changing to the second transition brightness setting value that is darker than the brightness setting of one side from the brightness setting of the other side, starting from the second transition brightness setting, the light quantity of the light source 11 is controlled in such a way that the brightness increases with time to become the brightness setting of one side. Therefore, when switching from a brighter brightness setting to a darker brightness setting, it does not suddenly switch to the darker brightness, but instead transitively switches to a brightness slightly darker than the darker brightness setting, and then slowly increases the brightness to change to the darker brightness setting. Thus, it is possible to alleviate the discomfort of the driver DR caused by the brightness switch and reduce the burden on the eyes.

[0080] In addition, as needed, the reflection unit 13 of the vehicle display device 1 according to the present embodiment includes a first mirror 131 and a second mirror 132. The first mirror 131 reflects the display light L1 and transmits the display light L2, and the second mirror 132 reflects the display light L2. When the display element 121 emits the display light L1, the first mirror 131 and the second mirror 132 make the positional relationship between the optical focus F of the imaging optical system including the windshield WS and the reflection unit 13 and the display unit 12 be in the first state where the display unit 12 is closer to the opening 17 side than the optical focus F, so that the virtual image VI can be seen. When the display element 121 emits the display light L2, it makes it be in the second state where the display unit 12 is closer to the light source 11 side than the optical focus F, so that the real image RI can be seen. Therefore, the switching between the real image RI display and the virtual image VI display can be smoothly performed.

[0081] (Second Embodiment of the Present Invention)

[0082] Use Figure 12 The vehicle display device 1 of this embodiment will be described. The vehicle display device 1 of this embodiment has a configuration in which the HUD device 2 has two image generation units (PGU, Picture Generation Unit). In addition, in this embodiment, the description overlapping with the first embodiment is omitted.

[0083] Figure 12 It is a diagram showing the configuration of the vehicle display device 1 of this embodiment. Figure 12 In this, the HUD device 2 of the vehicle display device 1 includes a first PGU 10a, a second PGU 10b, a reflection unit 13, and a control unit 15, and they are housed in a housing 16. The first PGU 10a includes: a first light source 11a that emits light in, for example, the visible wavelength region; and a first display unit 12a that transmits the light emitted from the first light source 11a and displays a real image RI of a display image formed in front of the driver DR. The second PGU 10b includes at least: a second light source 11b that emits light in, for example, the visible wavelength region; and a second display unit 12b that transmits the light emitted from the second light source 11b and displays a virtual image VI of a display image formed in front of the driver DR. The reflection unit 13 reflects a first display light L11 representing the display image displayed on the first display unit 12a and a second display light L22 representing the display image displayed on the second display unit 12b toward the windshield WS (light-transmitting member). The control unit 15 controls the display contents of the first display unit 12a and the second display unit 12b, performs switching control of the first PGU 10a and the second PGU 10b, and performs brightness control by adjusting the light amounts of the light emitted from the first light source 11a and the second light source 11b.

[0084] In addition, as Figure 12 shown, the control unit 15 can be configured to be controlled by one control unit 15 for the first PGU 10a and the second PGU 10b, or can be configured as follows: the first PGU 10a and the second PGU 10b each have an independent control unit, and the control unit 15 performs interlocking control on these independent control units.

[0085] Figure 12 In the first PGU 10a shown, the first light source 11a is, for example, a light-emitting diode that emits light in the visible wavelength region and is mounted on a wiring board, and emits white light. The first display unit 12a is provided closer to the opening 17 side than the first light source 11a on the optical path, and has a TFT-type first display element (not shown) that forms a first display light L11 representing an arbitrary image according to a control signal transmitted from the control unit 15.

[0086] In addition, Figure 12 In the second PGU 10b shown, the second light source 11b is, for example, a light-emitting diode that emits light in the visible wavelength region and is mounted on a wiring board, and emits white light. The second display unit 12b is provided closer to the opening 17 side than the second light source 11b in the optical path, and has a TFT-type second display element (not shown) that forms the second display light L22 representing an arbitrary image according to a control signal transmitted from the control unit 15.

[0087] In addition, in the first PGU 10a and the second PGU 10b, in addition to the above, optical components such as a condenser lens, a cylindrical lens, a diffusion plate, and a polarizing plate can be arranged at arbitrary positions on the rear stage side of the first light source 11a and the second light source 11b, respectively.

[0088] Figure 12 In the [description], the reflection unit 13 includes: a first correction mirror 1310 that reflects the first display light L11 emitted from the first display unit 12a toward the second correction mirror 1320; a second correction mirror 1320 that reflects the first display light L11 emitted from the first correction mirror 1310 toward the concave mirror 1330; and a concave mirror 1330 that reflects the first display light L11 reflected and folded back by the first correction mirror 1310 and the second correction mirror 1320 and the second display light L22 transmitted through the second correction mirror 1320 toward the opening 17.

[0089] The surfaces of the first correction mirror 1310 and the second correction mirror 1320 are mirror surfaces and have a complex free-form surface shape for correcting image distortion seen by the driver DR. In addition, the second correction mirror 1320 is, for example, a semi-reflection mirror that allows the second display light L22 representing the virtual image VI displayed on the second display unit 12b to pass through. The second display light L22 transmitted through the second correction mirror 1320 directly enters the concave mirror 1330. The concave mirror 1330 is rotatably provided and rotates according to the eye position of the driver DR, arbitrarily changing the emission directions of the first display light L11 and the second display light L22, thereby adjusting the position of the image. In particular, when the first display light L11 displays a real image RI and the second display light L22 displays a virtual image VI, there are times when it is desired to make the angles of their display surfaces different (for example, the virtual image VI is displayed inclined with respect to the road surface, and the real image RI is displayed in a state perpendicular to the road surface). By adjusting through this rotational drive, the display images can be displayed at angles suitable for the real image RI and the virtual image VI, respectively.

[0090] The first correction mirror 1310 is arranged closer to the opening 17 than the first PGU 10a in the optical path of the first display light L11, and is also arranged closer to the first PGU 10a than the first optical focus F1 of the imaging optical system including the windshield WS, the second correction mirror 1320, and the concave mirror 1330. Furthermore, the second display unit 12b of the second PGU 10b is arranged closer to the opening 17 than the second optical focus F2 of the imaging optical system including the windshield WS and the concave mirror 1330 in the optical path of the second display light L22.

[0091] With this configuration, when the first light source 11a is illuminated, the first display light L11 emitted from the first PGU 10a is reflected by the first correction mirror 1310, the second correction mirror 1320, the concave mirror 1330, and the windshield WS, allowing the driver DR to see a real image RI on the inside of the vehicle through the windshield WS. Furthermore, when the second light source 11b is illuminated, the second display light L22 emitted from the second PGU 10b is transmitted through the second correction mirror 1320, reflected by the concave mirror 1330, and the windshield WS, allowing the driver DR to see a virtual image VI on the outside of the vehicle through the windshield WS.

[0092] The control unit 15 cooperatively controls the first PGU10a and the second PGU10b, respectively, to turn on / off the first light source 11a, turn on / off the second light source 11b, control the display content of the first display unit 12a, control the display content of the second display unit 12b, and adjust the amount of light emitted by the first light source 11a and the second light source 11b to control the brightness of the first display light L11 emitted by the first display unit 12a and the second display light L22 emitted by the second display unit 12b.

[0093] In this embodiment, the control unit 15 controls the real image RI and the virtual image VI in the same manner as the brightness setting and changing manner described in the first embodiment. Figure 11 Flowchart of Figures 5 to 7 In each of the scenarios shown, Figure 8 The brightness value shown is controlled and is Figure 9 、 Figure 10 The brightness of the real image RI and the brightness of the virtual image VI are adjusted in the same way.

[0094] Further, in the first embodiment, the real image brightness adjustment unit 54a controls the brightness of the display light L2 for the real image RI that becomes the second polarization by adjusting the light amount of the light source 11, and the virtual image brightness adjustment unit 54b controls the brightness of the display light L1 for the virtual image VI that becomes the first polarization by adjusting the light amount of the light source 11. In this embodiment, the real image brightness adjustment unit 54a controls the brightness of the first display light L11 by adjusting the light amount of the first light source 11a that is the light source for the real image RI, and the virtual image brightness adjustment unit 54b controls the brightness of the second display light L22 by adjusting the light amount of the second light source 11b that is the light source for the virtual image VI.

[0095] Further, in the case of the configuration of the vehicle display device 1 shown in Figure 12 , the real image RI and the virtual image VI can be simultaneously displayed by turning on both the first light source 11a and the second light source 11b. For this simultaneous display, the control unit 15 controls the brightness of the real image RI and the virtual image VI according to the Figures 5 to 7 display brightness setting information 52 (real image display brightness setting value and virtual image display brightness setting value) in each of the scenes shown. That is, in the Figure 5 daytime and Figure 6 evening cases, the control is such that the brightness of the virtual image VI displayed outside the vehicle is relatively higher than the brightness of the real image RI displayed inside the vehicle. In the Figure 7 night case, the control is such that the brightness of the real image RI displayed inside the vehicle is relatively higher than the brightness of the virtual image VI displayed outside the vehicle.

[0096] In addition, when the ambient light outside or inside the vehicle changes from a brighter state to a darker state, or from a darker state to a brighter state in the state where the real image RI and the virtual image VI are simultaneously displayed (for example, when entering a tunnel during the day and when coming out of the tunnel, etc.), the control unit 15 controls the brightness of each display image according to the transition of each scene. Specifically, for example, when changing from a brighter state during the day (for example, corresponding to the case of Figure 5 or Figure 6 ) to a darker state inside the tunnel (for example, corresponding to the case of Figure 7 ), the control changes from a display state where the brightness of the real image RI is low and the brightness of the virtual image VI is high to a display state where the brightness of the real image RI is high and the brightness of the virtual image VI is low. In addition, when coming out of the tunnel from a darker state inside the tunnel (for example, corresponding to the state of Figure 7 ) and changing to a brighter state during the day (for example, corresponding to Figure 5 or Figure 6 ), the control changes from a display state where the brightness of the real image RI is high and the brightness of the virtual image VI is low to a display state where the brightness of the real image RI is low and the brightness of the virtual image VI is high.

[0097] As described above, in the case where the vehicle display device 1 of the present embodiment has a configuration including two first PGUs 10a and a second PGU 10b, similar to the case of the first embodiment, it is possible to avoid visual discomfort or glare caused by the driver DR. In addition, it is possible to simultaneously display the virtual image VI and the real image RI, and in this case, it is also possible to avoid visual discomfort or glare caused by the driver DR by adjusting their respective brightnesses.

Claims

1. A display device for a vehicle, characterized in that, A vehicle including a seat on which an occupant is seated and a light-transmitting member, in which display light is emitted from an emission port toward the light-transmitting member, so that a virtual image and a real image of a display image represented by the display light can be seen, and including: A display unit including a display element that transmits light emitted from a light source and displays the display image; A reflection unit that reflects light representing the display image displayed on the display unit toward the light-transmitting member; and A control unit; The control unit performs light amount control processing to control the light amount of the light source such that there is a prescribed brightness difference between a first display brightness setting when the real image is to be seen and a second display brightness setting when the virtual image is to be seen.

2. The vehicle display device according to claim 1, wherein In the light amount control processing, The control unit controls the light amount of the light source such that the second display brightness setting becomes brighter than the first display brightness setting.

3. The vehicle display device according to claim 1, wherein In the light amount control processing, The control unit controls the light amount of the light source such that the first display brightness setting becomes brighter than the second display brightness setting.

4. The vehicle display device according to claim 2, wherein When the headlamp provided on the vehicle is turned off, or when the illuminance of external light detected by an illuminance sensor provided on the vehicle is less than a prescribed value, the control unit performs the light amount control processing to control the light amount of the light source such that the second display brightness setting becomes brighter than the first display brightness setting.

5. The vehicle display device according to claim 3, wherein When the headlamp provided on the vehicle is turned on, or when the illuminance of external light detected by an illuminance sensor provided on the vehicle is equal to or greater than the prescribed value, the control unit performs the light amount control processing to control the light amount of the light source such that the first display brightness setting becomes brighter than the second display brightness setting.

6. The vehicle display device according to any one of claims 2 to 5, wherein When switching from the brightness setting on the relatively darker side among the first display brightness setting and the second display brightness setting in the light amount control processing to the relatively brighter other side, The control unit controls the light amount of the light source by the following method: after changing from the brightness setting on the one side to a first transition brightness setting that is darker than the brightness setting on the other side, starting from the first transition brightness setting, the brightness is increased with time change to become the brightness setting on the other side.

7. The vehicle display device according to any one of claims 2 to 5, wherein When switching from the relatively brighter other side brightness setting among the first display brightness setting and the second display brightness setting in the light amount control processing to the relatively darker one side brightness setting, The control unit controls the light quantity of the light source in the following manner: after changing from the brightness setting on the other side to a second transition brightness setting that is darker than the brightness setting on one side, starting from the second transition brightness setting, the brightness is increased over time to become the brightness setting on one side.

8. The vehicle display device according to claim 1, wherein the reflecting portion includes: a first mirror that reflects a first light ray and transmits a second light ray; and a second mirror that reflects the second light ray; the first mirror and the second mirror are arranged in the following manner: when the display element emits the first light ray, the positional relationship between the optical focus of the imaging optical system including the light-transmitting member and the reflecting portion and the display portion becomes a first state, that is, the display portion is closer to the light exit side than the optical focus, so that the virtual image is seen; when the display element emits the second light ray, it becomes a second state, that is, the display portion is closer to the light source side than the optical focus, so that the real image is seen.

Images