Display device for vehicle

Abstract

To provide a display device for a vehicle that can improve visibility.SOLUTION: A display device 1 includes: a display portion 11 that emits display light L related to an aerial image V formed of real images; a windshield 4 that has an inside surface 4a facing a viewer 5 side and an outside surface 4b opposite to the inside surface 4a, reflects the display light L toward a viewer 5, and forms the aerial image V on an inside surface 4a side; a light control film 15 that is disposed to overlap the windshield 4 and makes transmittance of external light incident from an outside surface 4b side variable at least between first transmittance and second transmittance smaller than the first transmittance; and a control portion 17 that controls at least a region of the light control film 15 on an extension line in a visual line direction on the viewer 5 with respect to the aerial image V to have the second transmittance.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present disclosure relates to a display device for a vehicle.

Background Art

[0002] Conventionally, a technique is known in which display light is reflected by a windshield of a vehicle, and a virtual image formed of a real image is visually recognized inside the vehicle. A viewer such as a driver visually recognizes this virtual image with the windshield as a background.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] The windshield transmits external light such as sunlight from outside the vehicle into the vehicle. When the external light transmitted through the windshield overlaps during the display of the virtual image, the visibility of the virtual image may be significantly reduced, and countermeasures are required.

[0005] The present disclosure has been made in consideration of such circumstances, and an object thereof is to provide a display device for a vehicle capable of improving visibility.

Means for Solving the Problems

[0006] In order to solve the above-described problems, a display device according to the present disclosure includes a display unit that emits display light related to a virtual image formed of a real image, an inner surface facing the viewer side, and an outer surface opposite to the inner surface, and a reflecting member that reflects the display light toward the viewer and forms a virtual image on the inner surface side, a dimming film that is disposed so as to overlap the reflecting member and variably changes the transmittance of external light incident from the outer surface side between at least a first transmittance and a second transmittance smaller than the first transmittance, and a control unit that controls the region of the dimming film on at least the extension line of the viewing direction of the viewer with respect to the virtual image to the second transmittance.

Effect of the Invention

[0007] In the display device for a vehicle according to the present disclosure, visibility is excellent.

Brief Description of the Drawings

[0008]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Mode for Carrying Out the Invention

[0009] An embodiment of the display device for a vehicle according to the present disclosure will be described with reference to the accompanying drawings. The display device for a vehicle according to the present disclosure can be applied to display devices mounted on vehicles such as automobiles, ships, agricultural machines, and construction machines.

[0010] FIG. 1 is a diagram showing a system configuration example of a display device 10 which is an embodiment of the vehicle display device of the present disclosure. In the following description, "front", "rear", "upper", and "lower" follow the definitions "Fr.", "Re.", "To.", and "Bo." in FIG. 1. Note that the left-right direction is a direction orthogonal to the front-rear-upper-lower directions.

[0011] The display device 10 is mounted, for example, in front of the front seat of the vehicle 1. The display device 10 emits display light L from the opening 3 of the instrument panel 2. The display device 10 projects this display light L from the rear (rearward in the traveling direction) of the vehicle 1 onto the windshield 4 (reflective member) of the vehicle 1 and reflects it. The display device 10 displays an aerial image V composed of a real image based on the display light L on the instrument panel 2 and allows a viewer 5 (for example, a driver), who is a passenger of the vehicle 1, to view it. The display light L is, for example, a character that provides various information to the driver or the like, or an image for providing entertainment to the driver or the like.

[0012] The display device 10 mainly includes a display unit 11, a windshield 4, a dimming film 15, and a control unit 17.

[0013] The display unit 11 emits light related to the aerial image V. The display unit 11 mainly includes a display, an optical system, and a housing.

[0014] The display is a display device such as a liquid crystal display, an organic EL display, a rear projection type projector, or a micro LED display that uses micro LEDs on the order of micro to form one pixel, and thousands or tens of thousands of these are tiled in a grid pattern, and an image is displayed based on the difference in illumination intensity of each pixel. The display displays an image related to the virtual image V and emits display light L representing this image. The optical system is one or more reflectors or the like that reflect or refract the display light L emitted from the display toward the windshield 4. The optical system has a known configuration necessary for displaying the virtual image V related to the real image. The housing houses the display and the optical system, and the display is arranged as one unit within the instrument panel 2. Each part of the display unit 11 is arranged so as to obtain a focal length capable of forming a virtual image V that is a real image on the instrument panel 2 through the reflection of the display light L on the windshield 4. For example, the display unit 11 may have a drive unit that drives the display or the optical system, and drive the display and the optical system according to the position of the viewer 5 and the display position of the virtual image V.

[0015] The windshield 4 is the front (windshield) glass of the vehicle 1, and in this embodiment, it functions as a reflecting member that reflects the display light L toward the viewer 5. The windshield 4 has an inner surface 4a facing the viewer 5 side and an outer surface 4b opposite to the inner surface 4a. The windshield 4 reflects the display light L toward the viewer 5 and forms a virtual image V on the instrument panel 2 on the inner surface 4a side.

[0016] The dimming film 15 is arranged between the inner surface 4a and the outer surface 4b of the windshield 4 so as to be superimposed on the windshield 4. The dimming film 15 variably adjusts the transmittance of external light LO incident from the outer surface 4b side between at least a first transmittance and a second transmittance that is smaller (lower) than the first transmittance. When the dimming film 15 has the first transmittance, the viewer 5 can view the scenery in front through the windshield 4. When the dimming film 15 has the second transmittance, the scenery in front through the windshield 4 is in a semi-transparent state (smoky state) or a substantially non-transparent state where it is difficult to view.

[0017] Specifically, the dimming film 15 is a film having a known configuration that variably changes the transmittance of any region of the dimming film 15 based on electrical control. The dimming film 15 is controlled to a second transmittance in a region that is at least on the extension line of the line-of-sight direction of the viewer 5 who views the aerial image V. Here, FIG. 2 is an explanatory diagram of the dimming film 15.

[0018] The dimming film 15 can arbitrarily select a region to have the second transmittance so that the region of the dimming film 15 on the extension line of the line-of-sight direction with respect to the aerial image V of the viewer 5 has the second transmittance. For example, when the aerial image Va is being displayed, the rectangular region 15a of the dimming film 15 can have the second transmittance. Also, when the aerial images Vb and Vc are being displayed, the rectangular regions 15b and 15c can each have the second transmittance.

[0019] Note that the dimming film 15 is disposed in a region below the windshield 4 and in a region where there is no problem with making it semi-transparent in accordance with the regulations applicable to the vehicle 1.

[0020] The control unit 17 is a control circuit board that controls the display unit 11 and the dimming film 15. The control unit 17, for example, based on an instruction from a vehicle ECU or the like, causes a required image to be generated on the display unit 11, controls the driving unit of the display unit 11, and controls the display unit 11 (display light L) to variably change the imaging position of the aerial image V on the instrument panel 2. Also, the control unit 17 controls the region that becomes the second transmittance of the dimming film 15 following the imaging position of the aerial image V.

[0021] The control unit 17 can control the transmittance of the dimming film 15 to the second transmittance when a predetermined condition is satisfied.

[0022] For example, based on the detection result of the illuminance sensor of the vehicle 1, when the illuminance is equal to or greater than a predetermined value, the control unit 17 sets the transmittance to the second transmittance. That is, when the illuminance is equal to or greater than a value at which the visibility of the aerial image V can be considered to be hindered by the external light LO, the control unit 17 sets the dimming film 15 to the second transmittance so as not to transmit the external light LO. On the other hand, when the illuminance is lower than a value at which the visibility of the aerial image V can be considered not to be hindered by the external light LO, since there is no need to control the transmittance of the dimming film 15, the control unit 17 sets the dimming film 15 to the first transmittance. Further, when the vehicle 1 is stopped (parked) or in the autonomous driving mode, the control unit 17 sets the dimming film 15 to the second transmittance regardless of the illuminance of the external light LO. That is, when the viewer 5 is the driver during manual driving, since setting the dimming film 15 to the second transmittance may hinder the driver's view in front of the vehicle, the control unit 17 sets the dimming film 15 to the first transmittance.

[0023] Next, the specific processes executed in the display device 10 of the present embodiment will be described in detail.

[0024] FIG. 3 is a flowchart for explaining the transmittance control process executed by the display device 10 in the present embodiment. This transmittance control process is started, for example, when the ignition switch of the vehicle 1 is turned on, and is repeatedly executed until it is turned off.

[0025] In step S1, the control unit 17 determines whether or not the aerial image V is being displayed. When the control unit 17 determines that the aerial image V is not being displayed (NO in step S1), in step S2, the dimming film 15 is set to the first transmittance so that the viewer 5 can visually recognize the forward scenery through the windshield 4. On the other hand, when the control unit 17 determines that the aerial image V is being displayed (YES in step S1), in step S3, it determines whether or not a predetermined condition for controlling the dimming film 15 to the second transmittance is satisfied. Specifically, the control unit 17 determines whether or not the illuminance is equal to or less than a predetermined value, whether the vehicle 1 is stopped or in autonomous driving, and the like. When the control unit 17 determines that the predetermined condition is not satisfied (NO in step S3), it proceeds to step S2 and sets the transmittance to the first transmittance.

[0026] On the other hand, when the control unit 17 determines that the predetermined condition is satisfied (YES in step S3), in step S4, the dimming film 15 is set to the second transmittance. That is, the control unit 17 makes the dimming film 15 in a smoked state to enhance the visibility of the aerial image V without transmitting the external light LO. After the transmittance control steps S2 and S4, the process returns to the display determination step S1, and the subsequent processes are repeated.

[0027] In the display device 10 according to such an embodiment, the dimming film 15 is disposed on the windshield 4 that serves as the background of the aerial image V, and by reducing the transmittance of the external light LO and changing the dimming film 15 to a dark color, the contrast with the background of the aerial image V can be ensured and the visibility of the aerial image V can be improved.

[0028] Further, the display device 10 can maintain the safety during driving and suppress unnecessary control by reducing the transmittance of the dimming film 15 only when a predetermined condition is satisfied.

[0029] Although some embodiments of the present invention have been described, these embodiments are presented by way of example and are not intended to limit the scope of the claims. These novel embodiments can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the gist of the invention. These embodiments and their modifications are included in the scope and gist of the invention, and are included in the invention described in the claims and the equivalent scope thereof.

[0030] For example, as shown in FIG. 4, the dimming film 15 may be attached not only between the inner surface 4a and the outer surface 4b of the windshield 4, but also to the inner surface 4a.

[0031] Further, the region controlled to the second transmittance of the dimming film 15 is not limited to the rectangular shape shown in FIG. 2, and may be in a diamond-shaped checkered pattern or a circular shape as shown in FIG. 5. Further, the outer edge of the region controlled to the second transmittance may be in a blurred state such that the transmittance gradually transitions from the second transmittance to the first region from within the region to outside the region.

[0032] The condition establishment determination step S3 described in FIG. 3 may be omitted. That is, the control unit 17 may always control the dimming film 15 to the second transmittance if the aerial image V is being displayed. Further, the control unit 17 may set the entire region of the dimming film 15 where the transmittance can be changed to the second transmittance if the aerial image V is being displayed.

[0033] The display device may also serve as a head-up display that can display not only a real image but also an aerial image related to a virtual image in front of the vehicle by driving and controlling a display and an optical system.

Explanation of Reference Numerals

[0034] 1 Vehicle 2 Instrument Panel 3 Opening 4 Windshield (Reflection Member) 4a Inner Surface 4b Outer Surface 5 Viewing person 10 Display device (vehicle display device) 11 Display unit 15 Dimming film 15a, 15b, 15c Regions 17 Control unit L Display light V, Va, Vb, Vc Aerial images

Claims

1. A display unit that emits display light related to a virtual image composed of a real image, A reflecting member having an inner surface facing the viewer side and an outer surface opposite to the inner surface, reflecting the display light toward the viewer and forming the virtual image on the inner surface side, A dimming film that is disposed so as to overlap the reflecting member and variably changes the transmittance of external light incident from the outer surface side between at least a first transmittance and a second transmittance smaller than the first transmittance, A display device comprising: a control unit that controls a region of the dimming film on at least an extension line in the line-of-sight direction of the viewer with respect to the virtual image to the second transmittance.

2. The display unit controls the display light so that the imaging position of the virtual image is variable, The control unit controls a region that becomes the second transmittance following the imaging position. The display device according to Claim 1.

3. The dimming film is disposed between the inner surface and the outer surface of the reflecting member or attached to the inner surface of the reflecting member. The display device according to Claim 1.

4. The display unit is disposed in an instrument panel of a vehicle, The reflecting member is disposed on a windshield of the vehicle. The display device according to Claim 1.

5. When the illuminance is equal to or higher than a predetermined value, the control unit sets the dimming film to the second transmittance. The display device according to Claim 4.

6. When the vehicle is stopped or in an autonomous driving state, the control unit sets the dimming film to the second transmittance. The display device according to Claim 4.

Images