JP2008051970A - Head-up display device for vehicle - Google Patents

Abstract

Reflection of display light from a first display device on the back surface of a half mirror is suppressed, thereby suppressing a virtual image of display information from the first display device from appearing double.
A black paint layer 41 is provided on the entire back surface 40b of the half mirror 4 except for a portion through which display light from a second display device is transmitted. Thus, when a part of the display light enters the half mirror 4 and reaches the back surface 40b of the half mirror 4 from the first display device, it is absorbed by the black paint layer 41 and again from the front surface of the half mirror 4 to the front windshield. Therefore, it is possible to prevent the virtual image of the display information displayed on the front windshield, that is, the speedometer from appearing double.
[Selection] Figure 6

Description

  The present invention relates to a vehicle head-up display device, and is suitable for use in, for example, an automobile.

As a conventional head-up display device, for example, a first display device and a second display device are disposed in the vicinity of an instrument panel in a vehicle cabin, and the display light is reflected from the first display device by a half mirror and the half mirror The display light from the second display device arranged behind is transmitted, and the reflected light and the transmitted light are respectively incident on the front windshield so that each of the first and second display devices is in front of the driver's visual field. Some display information is displayed as virtual images (see Patent Document 1).
Japanese Patent Laid-Open No. 11-91404

  In the head-up display device described in Patent Document 1, most of the display light from the first display device is reflected by the surface of the half mirror, but a part of the display light is reflected by the back surface of the half mirror. The reflected light from the front surface of the half mirror and the reflected light from the back surface of the half mirror have different optical paths depending on the thickness of the half mirror, and therefore the incident points on the front windshield of both reflected light are different. As a result, the virtual image of the display information displayed by the first display device formed on the front windshield appears double, and the appearance of the virtual image display by the head-up display device may be deteriorated.

  The present invention has been made in view of the above-described problems, and suppresses reflection of display light from the first display device on the back surface of the half mirror, so that a virtual image of display information from the first display device is doubled. An object of the present invention is to provide a vehicle head-up display device that can be prevented from being seen.

  In order to achieve the above object, the present invention employs the following technical means.

  According to a first aspect of the present invention, there is provided a vehicle head-up display device that includes first and second display devices that are disposed in the vicinity of an instrument panel in a vehicle interior and emit display information as display light, respectively. A half mirror that reflects the display light from the device and transmits the display light from the second display device so that the reflected light and the transmitted light enter the front windshield in front of the driver's field of view. A vehicle head-up display device that forms a reflected virtual image in front of a driver's field of view with reflected light and transmitted light from an incident half mirror, and display light from a second display device is transmitted to the back surface of the half mirror. It is characterized in that a reflection suppressing layer is formed over the entire area excluding the portion.

  According to the above-described configuration, the light that has entered the half mirror without being reflected by the surface of the half mirror out of the display light from the first display device is absorbed by the reflection suppression layer when it reaches the back surface of the half mirror. The light is not emitted again from the surface of the half mirror toward the front windshield. Furthermore, since the reflection suppressing layer is applied to the entire area except for the portion where the display light from the second display device is transmitted to the back surface of the half mirror, the display light from the second display device is blocked by the reflection suppressing layer. Can be transmitted through the half mirror. As a result, while the display information from the second display device is normally visually recognized, the virtual image of the display information by the first display device formed on the front windshield looks double, and the virtual image display by the head-up display device is displayed. It is possible to suppress the problem of poor appearance.

  The vehicle head-up display device according to claim 2 of the present invention is characterized in that the shape of the portion not provided with the reflection suppressing layer is the same as the shape of the display design formed by the display light from the second display device. It is said.

  According to such a configuration, the virtual image of the display information by the first display device imaged on the front windshield is doubled with the area of the portion where the antireflection layer is not provided on the back surface of the half mirror as a necessary minimum. It is possible to suppress a problem that the appearance of the virtual image display by the head-up display device is deteriorated.

  The vehicle head-up display device according to claim 3 of the present invention is characterized in that the antireflection layer is formed of a black or dark paint.

  According to such a configuration, the reflection suppressing layer can be applied to the back surface of the half mirror by an easy and inexpensive means.

  According to a fourth aspect of the present invention, there is provided a head-up display device that is disposed in the vicinity of an instrument panel in a vehicle interior and that emits display information as display light, and reflects display light from the display device. A half mirror that makes this reflected light incident on the front windshield in front of the driver's field of view, a light emitting device that is placed behind the half mirror so that light can be incident on the half mirror, and the half mirror partly emits light from the light emitting device Display light forming means that emits display light of a predetermined shape as transmitted light by blocking, and reflected from the half mirror of the display light of the display device incident on the front windshield and from the half mirror of the light of the light emitting device The vehicle head-up display device forms a reflected virtual image in front of the driver's field of view with transmitted light of Light forming means is a reflection suppression layer, antireflection layer is characterized in that applied to the entire region except for the transmissive portion of the light transmitted through the back surface of the half mirror.

  Even with the above-described configuration, while the display information formed by the display light forming means is normally visually recognized, the virtual image of the display information formed by the display device formed on the front windshield appears double, and the head-up display device A problem that the appearance of the virtual image display is deteriorated can be suppressed.

  Hereinafter, an embodiment of a vehicle head-up display device according to the present invention will be described with reference to the drawings, taking as an example a case where the vehicle is applied to a head-up display device 1 mounted in an automobile.

  The head-up display device 1 according to an embodiment of the present invention includes a digital speedometer S that indicates the running speed of the automobile by numbers, and a master warning W. Here, the master warning W is displayed in order to call the driver's attention only when some abnormality occurs in the vehicle. As shown in FIG. 4, a figure composed of an equilateral triangle and an exclamation mark. Is displayed.

  The head-up display device 1 according to the embodiment of the present invention mainly includes a first display device 2, a second display device 3, and a half mirror 4. As shown in FIG. 1, the first display device 2, the second display device 3, and the half mirror 4 are housed and fixed in the casing 5. The casing 5 is disposed on the back side of the instrument panel 8 that extends forward of the driver's seat of the vehicle and from the lower edge of the front windshield 7 of the vehicle to the lower part of the vehicle interior.

  The 1st display apparatus 2 comprises the speedometer S, and is provided with the transmissive liquid crystal panel 2a and the light source 2b. On the transmissive liquid crystal panel 2a, numbers and letters representing the traveling speed of the vehicle are formed as display information. When the transmissive liquid crystal panel 2a is irradiated with light from the light source 2b disposed behind, the first display device 2 emits numbers and characters representing the traveling speed of the vehicle as display light.

  The second display device 3 constitutes a master warning W, and includes a display pattern screen 3a and a light source 3b. When the display pattern screen 3a is transmitted and illuminated by the light from the light source 3b, a master warning display X as display information is emitted from the second display device 3 as display light. The display pattern screen 3a forms a master warning W figure shown in FIG. 3 by printing or the like on, for example, a translucent resin film or thin plate. In the head-up display device 1 according to the embodiment of the present invention, the master warning W figure is formed of a translucent orange color, and the periphery of the master warning W figure is formed of a light-shielding black color. The light source 3b is a so-called surface light source that is composed of a light emitter, for example, a white light emitting diode (not shown) and a light diffusing plate (not shown), and an area including the master warning W figure emits light in a planar shape. When the display pattern screen 3a is transmitted and illuminated by the light from the light source 3b, the master warning W figure, that is, the equilateral triangle and the exclamation mark in FIG.

  As shown in FIG. 4, the half mirror 4 has, for example, a dielectric material on the surface of the substrate 40 formed by forming a thin sheet of glass, for example, a curved curved surface, specifically, the surface 40a on the side where the concave surface is formed. It is formed by coating a body multilayer film (not shown). For this reason, the half mirror 4 has a property of reflecting a part of light incident on the surface 40a from the outside as a concave mirror and transmitting the remainder of the incident light. That is, the half mirror 4 functions as a concave mirror for light incident on the surface 40a from the right side in FIG. 4, that is, display light emitted from the first display device 2, and has a certain degree of light transmittance. is doing. Therefore, in FIG. 4, part of the light incident on the back surface 40 b of the half mirror 4 from the left side can pass through the half mirror 4.

  As shown in FIGS. 1 and 4, the half mirror 4 is disposed with the surface 40 a, that is, the side on which the concave mirror is formed facing the first display device 2. As shown in FIGS. 1 and 4, the second display device 3 is disposed behind the half mirror 4, that is, on the side opposite to the first display device. As a result, the display light emitted from the first display device 2 is reflected by the surface 40 a of the half mirror 4, is simultaneously enlarged, and enters the front windshield 7. On the other hand, the display light emitted from the second display device 3 enters the back surface 40 b of the half mirror 4, passes through the half mirror 4, and enters the front windshield 7.

  Here, the positional relationship between the half mirror 4 and the first display device 2 and the second display device 3 will be described.

  The first display device 2 is arranged to face the surface 40a of the half mirror 4 so that display light can enter the surface 40a. The second display device 3 is arranged to face the back surface 40b of the half mirror 4 so that display light can enter the back surface 40b. Further, as shown in FIG. 5, the first display device 2 and the second display device 3 are displaced so that the optical axes of the respective display lights do not cross each other, in other words, do not face each other. Are arranged in a relationship. As a result, as shown in FIG. 5, the display light from the first display device 2 enters the region A on the surface 40a of the half mirror 4, is reflected there and travels toward the front windshield 7, As shown in FIG. 5, the display light from the display device 3 is incident on the back surface 40b of the half mirror 4, and travels from the region B on the front surface 40a toward the front windshield 7.

  On the back surface of the half mirror 4, that is, the back surface 40b of the substrate 40, a black paint layer 41 is provided as a reflection suppressing layer. The black paint layer 41 has a matte and light shielding property. The black paint layer 41 is applied to the entire area of the back surface 40 b of the substrate 40 except for the part through which the display light from the second display device 3 is transmitted. That is, as shown in FIG. 6, the black paint layer 41 is applied so as to completely cover the area A of the front surface 40 a on the back surface 40 b of the substrate 40, that is, the area where the light emitted from the first display device 2 is incident. In addition, the display light emitted from the second display device 3 actually enters the region B of the front surface 40a on the back surface 40b of the substrate 40, that is, the region where the light emitted from the second display device 3 is emitted. It is given to the part except the part.

  Here, the portion where the display light emitted from the second display device 3 is actually incident on the back surface 40b of the substrate 40 has the same shape as the master warning W figure as shown in FIG.

  The display operations of the first display device 2 and the second display device 3 described above are controlled by a controller 6 (not shown). The controller 6 is composed of, for example, a microcomputer. The controller 6 drives the transmissive liquid crystal display 2a of the first display device 2 to control the turning on / off of the light source 2b. The controller 6 controls turning on / off of the light source 3 b of the second display device 3. The controller 6 is mounted on a circuit board or the like in a combination meter (not shown).

  The first display device 2, the second display device 3, and the half mirror 4 described above are accommodated and held in the casing 5, as shown in FIG. The casing 5 is made by molding a resin material, for example. As shown in FIG. 1, the casing 5 causes the display light from the first display device 2 reflected by the half mirror 4 and the display light from the second display device 3 transmitted through the half mirror 4 to enter the front windshield 7. For this purpose, an opening 5a is provided. The casing 5 is arrange | positioned at the back side of the instrument panel 8, as shown in FIG. The instrument panel 8 is also provided with an opening 8 a corresponding to the opening 5 a of the casing 5.

  Next, the electric circuit configuration and operation of the head-up display device 1 according to the embodiment of the present invention will be described with reference to FIG.

  As shown in FIG. 8, power is constantly supplied from the battery 11 to the controller 6. Moreover, the controller 6 is connected so that the ignition switch 10 can detect the operation state (ON or OFF).

  As shown in FIG. 4, the controller 6 is connected to the first display device 2 and the second display device 3. Further, the controller 6 includes a speed sensor 9 for detecting the traveling speed of the automobile, a fuel sender 12 for detecting the fuel level in the fuel tank, a temperature sensor 13 for detecting the engine coolant temperature, and an engine lubricating oil pressure. Each of the pressure sensors 14 is connected so that a detection signal can be input.

  When the ignition switch 10 is switched to the ON state by the driver's operation, the controller 6 detects it and starts the operation of the speedometer S. That is, the traveling speed of the vehicle is calculated based on the detection signal from the speed sensor 9, the transmission type liquid crystal display 2a of the first display device 2 is driven, and a number indicating the calculated speed is displayed. The light source 2b of the display device 2 is turned on. As a result, the first display device 2 emits display light for instructing the traveling speed of the automobile. The display light is reflected by the half mirror 4 and incident on the front windshield 7 and further reflected by the front windshield 7. Then, as shown in FIG. Thereby, as shown in FIG. 1, a virtual image K1 is formed in front of the front windshield 7, and the speedometer S is visually recognized.

  Here, the controller 6 also receives detection signals from the sensors 12, 13, and 14. When those signal levels are within the normal operating range, the controller 6 turns off the light source 3b of the second display device 3, and therefore the master warning W is not displayed. That is, the virtual image K2 is not formed in FIG. On the other hand, when the level of the detection signal from at least one of the sensors 12, 13, and 14 falls outside the normal operating range, the controller 6 turns on the light source 3b of the second display device 3, thereby causing a virtual image. K2 is imaged and a master warning W is displayed.

  Next, the function and effect obtained by providing the black paint layer 41 on the back surface 40b of the half mirror 4, which is a feature of the head-up display device 1 according to the embodiment of the present invention, will be described.

  First, in the conventional head-up display device, part of the display light enters the half mirror from the first display device, is reflected by the back surface of the half mirror, and is emitted from the half mirror again. The reflected light from the front surface of the half mirror and the reflected light from the back surface of the half mirror have different optical paths depending on the thickness of the half mirror, and therefore the incident points on the front windshield of both reflected light are different. As a result, the virtual image of the display information displayed by the first display device formed on the front windshield appears double, and the appearance of the virtual image display by the head-up display device may be deteriorated.

  On the other hand, in the head-up display device 1 according to the embodiment of the present invention, the black paint layer 41 is provided on the entire back surface 40b of the half mirror 4 except for the portion through which the display light from the second display device 3 is transmitted. Is provided. As a result, when a part of the display light enters the half mirror 4 from the first display device 2 and reaches the back surface 40b of the half mirror 4, it is absorbed by the black paint layer 41 and again from the front surface 40a of the half mirror 4 to the front. Since it does not radiate | emit toward the windshield 7, the virtual image K1 of the display information by the 1st display apparatus 2 imaged on the front windshield 7, ie, the speedometer S, does not look double. Therefore, the appearance of the virtual image display by the head-up display device 1 can be improved. On the other hand, the portion of the back surface 40b of the half mirror 4 through which the display light from the second display device 3 is transmitted, that is, the master warning W figure portion, is not provided with the black paint layer 41 and the translucency is maintained. Therefore, the virtual image K2 of the display information by the second display device 3, that is, the master warning W is clearly visually recognized as before.

  As described above, the virtual image K2 of the display information displayed by the second display device 3, that is, the master warning W is clearly visible as before, while the virtual image K1 of the display information displayed by the first display device 2, that is, the speedometer S is doubled. It is possible to improve the appearance of the virtual image display by the head-up display device 1 by suppressing the visibility.

  In the head-up display device 1 according to the embodiment of the present invention described above, a surface light emitting device as a light emitting device may be used instead of the second display device 3. In this case, if the irradiation range of the light from the surface light emitting device is the region B in FIG. 6, the light from the surface light emitting device is a translucent portion on the back surface 40 b of the half mirror 4, that is, the master warning W in FIG. By passing through the graphic portion, a virtual image K2 as the master warning W can be formed in front of the front windshield 7. According to such a configuration, the virtual image K <b> 2 as the master warning W can be formed with a simpler configuration than the second display device 3.

  In the head-up display device 1 according to the embodiment of the present invention, the speedometer S is formed by the first display device 2 and the master warning W is formed by the second display device 3. Other instruments such as a tachometer that displays the engine speed may be substituted. Further, the master warning W may be replaced with another display, for example, various warning displays.

  In the head-up display device 1 according to the embodiment of the present invention, the black paint layer 41 is used as the reflection suppression layer. However, the black paint layer 41 is not necessarily limited, and has a property of hardly reflecting incident light. Other materials may be used. For example, a dark blue paint layer may be used.

  Moreover, although the said embodiment demonstrated the example in which this invention was applied to the head-up display apparatus 1 for motor vehicles, generally, this invention is applied to the head-up display apparatus for various vehicles, without restricting to this. You may implement.

It is sectional drawing in the motor vehicle mounting state of the head-up display apparatus 1 by one Embodiment of this invention. It is II arrow directional view in FIG. It is a III arrow directional view in FIG. It is an external view of the half mirror 4 of the head-up display apparatus 1 by one Embodiment of this invention. It is a V arrow directional view in FIG. It is VI arrow directional view in FIG. It is the VII-VII sectional view taken on the line in FIG. It is a mimetic diagram explaining the electric circuit composition of head up display device 1 by one embodiment of the present invention.

Explanation of symbols

1. Head-up display device (vehicle head-up display device)
2 First display device 2a Transmission type liquid crystal display 2b Light source 3 Second display device 3a Display pattern screen 3a
3b Light source 4 Half mirror 40 Substrate 40a Front surface 40b Back surface 41 Black paint layer (reflection suppression layer)
DESCRIPTION OF SYMBOLS 5 Casing 5a Opening part 6 Controller 7 Front window shield 8 Instrument panel 8a Opening part 9 Speed sensor 10 Ignition switch 11 Battery 12 Fuel sender 13 Temperature sensor 14 Pressure sensor A, B area | region E Eye K1, K2 Virtual image S Speedometer W Master Warning

Claims (4)

First and second display devices that are arranged in the vicinity of an instrument panel in a vehicle interior and emit display information as display light, respectively;
A half mirror that reflects the display light from the first display device, transmits the display light from the second display device, and makes the reflected light and transmitted light enter the front windshield in front of the driver's field of view. ,
A vehicle head-up display device that forms a reflected virtual image in front of the driver's visual field by the reflected light and the transmitted light from the half mirror incident on the front windshield,
A head-up display device for a vehicle, wherein a reflection suppression layer is formed on the entire back surface of the half mirror except for a portion through which display light from the second display device is transmitted.   2. The vehicle head-up display device according to claim 1, wherein the shape of the portion not provided with the antireflection layer is the same as the shape of a display design formed by display light from the second display device.   3. The vehicle head-up display device according to claim 1, wherein the antireflection layer is formed of a black or dark paint. A display device arranged near the instrument panel in the interior of the vehicle and emitting display information as display light respectively;
A half mirror that reflects display light from the display device and causes the reflected light to enter the front windshield in front of the driver's field of view;
A light emitting device disposed behind the half mirror so that light can be incident on the half mirror;
The half mirror includes display light forming means for emitting display light having a predetermined shape as transmitted light by partially blocking light from the light emitting device,
A reflected virtual image is formed in front of the driver's visual field by the reflected light from the half mirror of the display light incident on the front windshield and the transmitted light from the half mirror of the light from the light emitting device. A head-up display device for a vehicle,
The display light forming means is a reflection suppressing layer,
The vehicle head-up display device, wherein the reflection suppression layer is applied to the entire area of the back surface of the half mirror except the transmitted light transmitting portion.

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