JP7492670B2 - Vehicle display device - Google Patents

Description

The present invention relates to a display device for a vehicle, such as a head-up display device, that displays a virtual image on the vehicle's front windshield, combiner, etc., and is also capable of capturing an image of the user.

A head-up display device generates and displays a virtual image using display light reflected by a reflective translucent material, such as the vehicle's front windshield or combiner, which is superimposed on the actual scene (the scenery in front of the vehicle) that passes through the reflective translucent material. By providing the user with the information they desire through a virtual image while minimizing the movement of the driver's line of sight, the head-up display device contributes to safe and comfortable vehicle operation.

Some head-up display devices illuminate the user with infrared light, capture an image of the user, and use the captured image to understand the user's condition.

For example, the head-up display device described in Patent Document 1 forms a display image by reflecting visible light emitted from a display means toward a user using a combiner member, and includes an infrared irradiating means for irradiating infrared light toward the user, a mirror member for reflecting the visible light emitted from the display means toward the combiner member and transmitting infrared light reflected by the user and the combiner member, a plurality of imaging means for sensing the infrared light transmitted through the mirror member and capturing images of the user from different directions, and an image processing means for calculating the position of the user's eyes based on images captured by the imaging means, making it possible to accurately calculate the position of the user's eyes.

JP 2008-126984 A

However, when the imaging means is installed on the rear side of the reflector (mirror member) (the side of the reflector opposite to the user and combiner member), as in the head-up display device described in Patent Document 1, the reflector must reflect visible light and transmit infrared light, which creates the problem of high manufacturing costs.

The present invention was made in consideration of the above circumstances, and aims to provide a vehicle display device that does not require a reflector to transmit infrared light.

In order to solve the above problems, the present invention provides a display device for a vehicle that reflects display light from a display light projection means by a reflecting mirror and projects it onto a reflective light-transmitting member, generates and displays a virtual image by the display light reflected by the reflective light-transmitting member superimposed on an actual image transmitted through the reflective light-transmitting member, and irradiates a user of the vehicle with infrared light from an infrared light irradiating means and images the user with an imaging means , the display device including a housing that accommodates the display light projection means, the reflecting mirror, and the imaging means, the imaging means being provided in a position that is not on the opposite side of the reflective light-transmitting member with respect to the reflecting mirror in the housing and does not overlap with the optical path of the display light from the reflecting mirror to the reflective light-transmitting member , and further the imaging means being provided on the housing at a center side in a vehicle width direction of the vehicle .

Further, the present invention provides a display device for a vehicle that reflects display light from a display light projection means by a reflecting mirror and projects it onto a reflective light-transmitting member, generates and displays a virtual image by the display light reflected by the reflective light-transmitting member superimposed on an actual scene transmitted through the reflective light-transmitting member, and irradiates a user of the vehicle with infrared light from an infrared light irradiating means and images the user with an imaging means, the display device including a housing that accommodates the display light projection means, the infrared light irradiating means, the reflecting mirror, and the imaging means, the infrared light irradiating means being provided on a side of the housing that is not opposite the side of the reflective light-transmitting member with respect to the reflecting mirror and at a position that does not overlap with an optical path of the display light from the reflecting mirror to the reflective light-transmitting member, the imaging means being provided on one end side of the housing in a vehicle width direction of the vehicle, and the infrared light irradiating means being provided on the housing on the other end side of the housing in the vehicle width direction of the vehicle.

The intersection of the optical axis of the imaging means with the reflective light-transmitting member may be located above the reflection point of the central optical path of the display light at the reflective light-transmitting member.

The housing may be provided with a shielding member on the side of the reflective translucent member that blocks visible light and transmits infrared light relative to the imaging means.

Alternatively, the housing may be provided with a translucent member through which the display light from the display light projection means, the infrared light from the infrared light irradiating means, and the infrared light reflected by the user and received by the imaging means pass , the optical axis of the infrared light irradiating means being positioned at a location where a vertical plane perpendicular to a plate surface of the translucent member overlaps with a plane perpendicular to the vertical plane and intersecting the plate surface at a predetermined acute angle, and the imaging means may be provided in a region between the plane and the translucent member.

A light blocking member for blocking infrared light may be provided between the infrared light irradiating means and the imaging means.

The present invention has the advantage that it is not necessary for the reflector in a vehicle display device to transmit infrared light.

1 is an explanatory diagram showing a vehicle provided with a head-up display device according to an embodiment of the present invention; FIG. 2 is an explanatory diagram showing a plan view of the head-up display device of FIG. 1 . 3 is a cross-sectional view taken along line AA in FIG. 2. 2 is an explanatory diagram showing an area in which a camera is provided in the head-up display device of FIG. 1 . 3A is a cross-sectional view taken along line BB in FIG. 2, and FIG. 3B is an explanatory diagram showing a configuration in which the position of the camera in FIG. FIG. 11 is an explanatory diagram showing, in a plan view, another example of a head-up display device according to an embodiment of the present invention. 7A is a cross-sectional view taken along line CC in FIG. 6, and FIG. 7B is an explanatory diagram showing a configuration in which the position of the camera in FIG. FIG. 11 is an explanatory diagram showing, in a plan view, still another example of a head-up display device according to an embodiment of the present invention. 9 is a cross-sectional view taken along line EE in FIG. 8. 6 is a cross-sectional view showing a configuration in which a light shielding plate is provided between the infrared light irradiation unit and the camera in FIG. 5( a ). FIG. 8 is a cross-sectional view showing a configuration in which a light shielding plate is provided between the infrared light irradiation unit and the camera in FIG. 10 is a cross-sectional view showing a configuration in which a light shielding plate is provided between the infrared light irradiation unit and the camera in FIG. 9 . FIG. 11 is a cross-sectional view showing a configuration in which the light blocking plate is short.

The embodiment of the present invention will be explained with reference to the drawings.

1, a head-up display device (HUD) 1 as a vehicle display device according to this embodiment is provided inside an instrument panel 4 below a windshield 3 of a vehicle 2, and projects display light _L1 , which is visible light, onto a part of the windshield 3. The display light _L1 is reflected by the windshield 3 to generate a virtual image V, which is superimposed on an actual scene transmitted through the windshield 3 and is visually recognized by a driver D sitting in a driver's seat (not shown) behind a steering wheel 5.

The HUD 1 also has a function of a DMS (driver monitoring system) that monitors the state of the driver D, and projects infrared light _L2 onto the driver D to capture an image of the driver D.

In detail, the HUD 1 is enclosed in a housing 6 molded from a black ABS resin or the like to prevent the intrusion of external light, separating it from the outside, and the housing 6 has an opening 8 formed therein to which is attached a transparent cover glass (transparent member) 7 made of polycarbonate or the like. Inside the housing 6, a display unit 9, a plane mirror 10, a concave mirror 11, an infrared light irradiation unit 12, a camera 13, and a shielding piece 14 as an invisible part are held and housed.

The display unit 9 is provided with a display 15 consisting of a light source, a liquid crystal panel, etc., and projects and displays image light (display light _L1 ) which is visible light from the display 15. The plane mirror 10 is made of glass molded to have a flat surface and has a metal such as aluminum or a dielectric multilayer film deposited thereon, and simply reflects visible light. The concave mirror 11 is made of resin such as polycarbonate molded to have a concave surface and has a metal such as aluminum deposited thereon, and magnifies and reflects visible light.

As shown in Figures 2 and 3, the infrared light irradiation unit 12 is provided in the housing 6 below the cover glass 7 at the center of the vehicle 2 in the vehicle width direction, and irradiates infrared light (near-infrared light) emitted by a light source consisting of a light-emitting diode through the shielding piece 14 and the cover glass 7 toward the front windshield 3.

On the other hand, the camera 13 is provided in the housing 6 below the cover glass 7, toward the center of the vehicle 2 in the vehicle width direction, and in front of the infrared light irradiation unit 12, and is equipped with an image sensor that is sensitive to the infrared light in the wavelength band irradiated from the infrared irradiation unit 12, and a lens that can transmit the infrared light and form an image on the image sensor, thereby capturing near-infrared images.

Both the infrared light irradiation unit 12 and the camera 13 are provided not on the back side of the plane mirror 10 (the side opposite the windshield 3 with respect to the plane mirror 10) and in a position not overlapping with the optical path _P1 of the display light _L1 from the plane mirror 10 to the windshield 3, and the intersection point x of the optical axis _O3 of the camera 13 (the central optical path of the camera 13, and a point on this optical path is imaged at the center of the camera's angle of view. Note that the optical axis _O3 is installed so as to face the center of the eye point determined by design, and its orientation is not limited as long as the entire eye box (the range in which the virtual image is viewed) is within the camera's angle of view) with the windshield 3 is located above the reflection point y on the windshield ₃ of the center _O1 of the optical path _P1 of the display light _L1 (the central optical path of the display light L1, and the light passing through this optical path generates the center of the virtual image V).

4, the camera 13 is provided in a region R between a plane S2 that includes the optical axis _O2 of the infrared light emitting unit 12 and is perpendicular to a vertical plane _S1 perpendicular to the cover glass ₇ , and the cover glass 7. In general, the optical axis _O2 of the infrared light emitting unit 12 extends rearward and upward from the infrared light emitting unit 12, so that the angle θ at which the plane _S2 intersects with the cover glass 7 is 90° or less, and the range of this angle θ defines the region R.

In addition, in this example, although detailed illustration is omitted here, the housing 6 has a pair of peripheral walls that are generally perpendicular (intersecting) to the vehicle width direction, and the infrared light irradiation unit 12 and the camera 13 are provided in a space in the housing 6 that is slightly inside one of the pair of peripheral walls (one of the peripheral walls) that is located closer to the imaginary center line that divides the vehicle into two equal parts left and right. Note that the housing 6 here has four peripheral walls, and the two peripheral walls that are generally aligned in the vehicle width direction shown in FIG. 1 are configured as upright walls that connect the ends of the pair of peripheral walls.

The shielding piece 14 blocks visible light and transmits infrared light, and is provided in the housing 5 above the infrared light emitting unit 12 and the camera 13, i.e., on the front windshield 3 side of the infrared light emitting unit 12 and the camera 13.

In the HUD 1, the display light _L1 from the display unit 9 is reflected by a plane mirror 10, then is magnified and reflected by a concave mirror 11, passes through the cover glass 7, and is projected onto the windshield 3. The display light _L1 projected onto the windshield 3 is magnified and reflected toward the driver D, generating a virtual image V, which is displayed to the driver D superimposed on the real view transmitted through the windshield 3.

On the other hand, the infrared light _L2 from the infrared light irradiation unit 12 passes through the shielding piece 14 and the cover glass 7 to be projected onto the windshield 3, and is reflected by the windshield 3 toward the driver D to irradiate the driver D. Then, when reflected by the driver D, part of the infrared light _L2 follows the reverse path, passes through the cover glass 7 and the shielding piece 14, and is incident on the camera ₁₃ , whereby the driver D is imaged. This imaging is performed periodically or irregularly while the virtual image V is being displayed, and the driver D is monitored based on the captured image.

The HUD 1 according to this embodiment reflects display light _L1 from a display unit 9 by a plane mirror 10 and projects it onto the windshield 3, generates and displays a virtual image V by the display light _{L1 reflected by the windshield 3 superimposed on the actual image transmitted through the windshield 3, and also irradiates infrared light L2 from an infrared light irradiation unit 12 to a driver D of a vehicle 2 and captures an image of the driver D with a camera 13. The HUD 1 includes} a display unit 9, a plane mirror 10, and a camera 13, as well as a housing 6 that accommodates the display unit 9, the plane mirror 10, and the camera 13. The camera 13 is provided on a side of the housing 6 that is not opposite the windshield 3 side with respect to the plane mirror 10 and at a position that does not overlap with the optical path P of the display light _L1 from the plane mirror ₁₀ to the windshield 3. Therefore, the plane mirror 10, which is not on the optical path P2 (see FIG. 3) of the infrared light _L2 received by the camera 13, does not need to transmit the infrared light _L2 , and the manufacturing costs can be reduced.

Here, the camera 13 is provided in the housing 6 at the center of the vehicle 2 in the vehicle width direction, so that external light is less likely to enter from the side windows of the vehicle 2, and the possibility of strong external light entering the camera 13 and interfering with the driver D's monitoring can be reduced.

Furthermore, the intersection point x of the optical axis _O3 of the camera 13 with the windshield 3 is located above the reflection point y (which is generally located at a position where the driver D looks down) of the center _O1 of the optical path _P1 of the display light _L1 on the windshield 3, so the optical path _P2 of the infrared light _L2 received by the camera 13 is not blocked by the instrument panel 4 and the steering wheel 5, and the camera 13 can capture an image of the face of the driver D from an angle close to the front.

The housing 6 is provided with a shielding piece 14 on the windshield 3 side of the camera 13 that blocks visible light and transmits infrared light. Therefore, the camera 13, which would be visible through the cover glass 7 in terms of the appearance of the HUD 1, is concealed by the shielding piece 14, improving the marketability of the HUD 1.

Furthermore, the housing 6 is provided with a cover glass 7 through which the display light _L1 from the display unit 9, the infrared light _L2 from the infrared light irradiation unit 12, and the infrared light _L2 reflected by the driver D and received by the camera 13 pass, and the camera 13 is provided in the housing 6 in a region R between the cover glass ₇ and a plane S2 that includes the optical axis _O2 of the infrared light irradiation unit 12 and is perpendicular to the vertical plane _S1 . As a result, as shown in FIG. 5(a), the angle at which the infrared light _L2 emitted from the infrared light irradiation unit 12 and reflected by the cover glass 7 is unlikely to enter the camera 13, and the occurrence of stray light due to the illumination light in the captured image can be suppressed (in FIG. 5 and FIGS. 7, 9 to 13 described later, α indicates the irradiation range of the infrared light irradiation unit 12, and β indicates the angle of view of the camera 13. If the camera 13 is not in the region R, the infrared light _L2 emitted from the infrared light irradiation unit 12 and reflected by the cover glass 7 is likely to enter the camera 13, as shown in FIG. 5(b).

6 shows an example in which the infrared light irradiation unit 12 and the camera 13 are arranged (side by side) on the left and right sides, not on the front and rear sides, in the housing ₆ at the center side in the vehicle width direction of the vehicle 2. As shown in FIG. 7(a), the camera 13 is provided in the region R between the cover glass 7 and a plane that includes the optical axis O2 of the infrared light irradiation unit 12 and is perpendicular to the vertical plane, so that the angle at which the infrared light _L2 emitted from the infrared light irradiation unit 12 and reflected by the cover glass 7 is unlikely to enter the camera 13, and the occurrence of stray light due to the illumination light in the captured image can also be suppressed (if the camera 13 is not in the region R, the infrared light _L2 emitted from the infrared light irradiation unit 12 and reflected by the cover glass 7 is likely to enter the camera 13, as shown in FIG. 7(b).).

8 shows an example in which the camera 13 is provided on one end (center side) of the housing 6 in the vehicle width direction of the vehicle 2, and the infrared light irradiation unit 12 is provided on the other end (outside) of the housing 6 in the vehicle width direction of the vehicle 2. Since the camera 13 is provided away from the infrared light irradiation unit 12 as shown in Fig. 9, the infrared light _L2 emitted from the infrared light irradiation unit 12 and reflected by the cover glass 7 is unlikely to enter the camera 13, and the occurrence of stray light due to the illumination light in the captured image can be suppressed.

10 to 12, a light shielding plate 16 for shielding the infrared light _L2 may be provided between the infrared light irradiation unit 12 and the camera 13. Here, Fig. 10 corresponds to Fig. 5(a) and Fig. 11 corresponds to Fig. 7(a), but if the infrared light _L2 emitted from the infrared light irradiation unit 12 and reflected by the cover glass 7 is blocked by the light shielding plate 16 and is less likely to enter the camera 13, the arrangement of the infrared light irradiation unit 12 and the camera 13 may be as shown in Fig. 5(b) or Fig. 7(b).

On the other hand, FIG. 12 corresponds to FIG. 9 , and light shielding plates 16 are provided adjacent to the infrared light irradiation unit 12 and the camera 13, which are originally located apart from each other, so that the risk of infrared light _L2 emitted from the infrared light irradiation unit 12 and reflected by the cover glass 7 entering the camera 13 can be further reduced.

The light shielding plate 16 does not necessarily have to be in contact with the cover glass 7, but if the light shielding plate 16 is short, as shown in Fig. 13, the infrared light _L2 emitted from the infrared light irradiation unit 12 and reflected by the cover glass 7 easily enters the camera 13, so it is preferable that the light shielding plate 16 extends farther than the emission surface (emission surface of the infrared light _L2 ) of the infrared light irradiation unit 12 as viewed from the cover glass 7, and it is preferable that the light shielding plate 16 extends farther than the incidence surface (incidence surface of the infrared light _L2 ) of the camera 13. In other words, it is preferable that the light shielding plate 16 extends from the cover glass 7 to the rear side of the infrared light irradiation unit 12 and the camera 13 so as to form a standing wall shape.

The above describes examples of embodiments of the present invention, but the embodiments of the present invention are not limited to those described above and may be modified as appropriate without departing from the spirit of the invention.

For example, in the above embodiment, the display light is projected onto the vehicle's front windshield as a reflective, light-transmitting member, but a combiner may be used instead of the front windshield.

The arrangement of the infrared light irradiation unit and the camera is not limited to the above, and as long as the camera is housed in the housing, the infrared light irradiation unit may be provided outside the housing (for example, on the steering column behind the steering wheel of the vehicle). Furthermore, the cover glass may be made of a dark (semi-transparent) material rather than a transparent one.

1. Head-up display device (vehicle display device)
2 Vehicle 3 Front windshield (reflective translucent member)
6. Housing
7 Cover glass (light-transmitting member)
9. Display light projection means (display unit)
10 Plane mirror (reflector)
12 Infrared light irradiation unit (infrared light irradiation means)
13 Camera (imaging means)
14 Shielding piece (shielding member)
16 Light shielding plate (light shielding member)
D Driver (user)
_L1 display light _L2 infrared light _O2 optical axis (optical axis of infrared light irradiation means)
O ₃ Optical axis (optical axis of the imaging means)
P ₁ Light path R Area S ₁ Vertical surface S ₂ Plane V Virtual image x Intersection y Reflection point

Claims (6)

A display device for a vehicle, which reflects display light from a display light projection means by a reflecting mirror and projects it on a reflective light-transmitting member, generates and displays a virtual image by the display light reflected by the reflective light-transmitting member in a manner superimposed on an actual scene transmitted through the reflective light-transmitting member, and also irradiates a user of the vehicle with infrared light from an infrared light irradiating means and images the user by an imaging means ,
a housing that houses the display light projection means, the reflecting mirror, and the imaging means;
the imaging means is provided at a position on the housing that is not on an opposite side of the reflecting mirror from the reflective light-transmitting member and does not overlap with an optical path of display light from the reflecting mirror to the reflective light-transmitting member ,
The display device for a vehicle is further characterized in that the imaging means is provided on the housing at a center side in a width direction of the vehicle . A display device for a vehicle, which reflects display light from a display light projection means by a reflecting mirror and projects it on a reflective light-transmitting member, generates and displays a virtual image by the display light reflected by the reflective light-transmitting member in a manner superimposed on an actual scene transmitted through the reflective light-transmitting member, and also irradiates a user of the vehicle with infrared light from an infrared light irradiating means and images the user by an imaging means,
a housing that houses the display light projection means, the infrared light irradiation means, the reflecting mirror, and the imaging means,
the infrared light irradiating means is provided at a position on the housing that is not on the opposite side of the reflecting mirror from the side of the reflective light-transmitting member and does not overlap with an optical path of the display light from the reflecting mirror to the reflective light-transmitting member,
The imaging means is provided on one end side of the housing in a vehicle width direction of the vehicle, and the infrared light irradiation means is provided on the other end side of the housing in the vehicle width direction of the vehicle . The vehicle display device according to claim 1 or 2, characterized in that the intersection point of the optical axis of the imaging means with the reflective translucent member is located above the reflection point of the central optical path of the display light at the reflective translucent member. The vehicle display device according to any one of claims 1 to 3, characterized in that the housing is provided with a shielding member on the side of the reflective translucent member relative to the imaging means that blocks visible light and transmits infrared light. the housing is provided with a translucent member through which the display light from the display light projection means, the infrared light from the infrared light irradiation means, and the infrared light reflected by the user and received by the imaging means pass;
A vehicle display device as described in any one of claims 1, 3, and 4, characterized in that the optical axis of the infrared light irradiation means is located at a location where a vertical plane perpendicular to the plate surface of the translucent member overlaps with a plane perpendicular to the vertical plane and intersecting the plate surface at a predetermined acute angle, and the imaging means is provided in an area between the plane and the translucent member. 3. The display device for a vehicle according to claim 2 , further comprising a light blocking member for blocking infrared light, which is provided between the infrared light emitting means and the image capturing means.

Images