JPH10963A - Display unit of vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To build the conventional expensive system displaying the vehicle information of a dashboard together with a heads-up display exclusive display unit into an inexpensive one instead. SOLUTION: This display unit uses a two-plane displaying fluorescent character display tube 10 capable of looking straight a displayed image as an actual image from both sides in place of the conventional dashboard, and a side showing a display form (positive display) that is normally readable when a driver looks straight at it is regarded as a surface image plane 11 of the display tube 10, and a side where a mirror image of the positive display comes out is as a back image plane 12, respectively. Subsequently, the mirror image being revealed on this back image plane 12 is reflected by a reflecting mirror 13, irradiating it onto a combiner 14 as a virtual image I.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle display device, and more particularly to a vehicle HUD (head-up display).

[0002]

2. Description of the Related Art HUDs used in automobiles irradiate an image of a display element illuminated by a light source onto a combiner provided on a driver side facing the lower region of the windshield glass or the windshield glass itself. A combiner or a windshield glass (hereinafter, represented by a combiner) is displayed as a screen. When the display contents of the instrument panel as shown in FIG. 8 below the driver's seat are displayed on the projection surface of the combiner using this HUD, the combiner is arranged on the upper surface of the instrument panel. You can look at the display on the instrument panel while looking forward without dropping your gaze downwards, especially for the elderly and beginners who are attentive to watching the road conditions while driving. Above is very effective.

[0003]

The HUD is used as an auxiliary display device for the instrument panel or the navigation system, etc. However, a HUD display requires a dedicated display device for the HUD. Equipped cars are very expensive.

[0004] In order to reduce the cost, it is conceivable that the display contents of the instrument panel are incorporated into the HUD and displayed only by the HUD without providing the instrument panel itself. In this case, however, a wide view of the windshield glass is considered. When the operator attempts to obtain the information, the combiner is in the way, and as shown in FIG. 9, when the projection surface 15 of the combiner 14 is turned down and the display is turned down, the driver cannot obtain information on the instrument panel at all. May be connected.

[0005] For example, if the parking brake is pulled and the HUD displays a warning on the combiner 14 and falls down to obtain a wide field of view as described above, the driver may stop the parking brake. The driver will drive without noticing the warning message.

[0006] Therefore, it is necessary to provide an instrument panel that always displays information or an indicator similar thereto. Among the display contents of the instrument panel, in particular, the above-described parking brake, charge warning, ABS abnormality warning, engine control, and the like. It is preferable that a warning display such as a unit abnormality warning is also displayed on the projection surface 15 of the combiner 14 in consideration of safety for the elderly and beginners.

[0007] However, as described above, it is very expensive to provide both the instrument panel and the display device dedicated to the HUD.

Therefore, an object of the present invention is to surely inform a driver of the contents of a warning and to transmit vehicle information on an instrument panel to H.
It is an object of the present invention to make a conventional expensive display system for displaying a display together with a display device dedicated to a UD into an inexpensive display system.

[0009]

In order to solve the above-mentioned problems, according to the present invention, the display device allows the display image to be directly viewed from the front and back, and the display image on the front side is directly visible to the driver. In this case, the display image on the back side is inverted through an optical member, and the inverted image is projected on the combiner or the windshield glass (claim 1).

With this configuration, the display can serve as both an instrument panel and a HUD display.

In the first aspect of the present invention, it is possible to employ a configuration in which a reflection mirror is used for the optical member, and switching between the projection and non-projection of the inverted image is performed by changing the reflectance of the reflection mirror. Claim 2). And
In order to change the reflectance of the reflector, a liquid crystal film may be provided on the reflection surface of the reflector, and the reflectance of the reflector may be changed by changing the light transmittance of the liquid crystal film ( Claim 3). Adjusting the light transmittance of the liquid crystal film simply involves displaying on / off
In addition to switching of non-display, the light transmittance can be set to a level between complete transmission and complete non-transmission, and the brightness of the projected image can be adjusted.

Further, in the first aspect of the present invention, a liquid crystal shutter may be provided on a display surface of the display, and switching between display and non-display may be performed by the liquid crystal shutter. ). According to the liquid crystal shutter, partial display / non-display of the display screen can be switched.

[0013] The liquid crystal shutter may be a light scattering type liquid crystal shutter. The light scattering type liquid crystal shutter has no loss due to the absorption of light by the polarizing plate as compared with the one having the polarizing plate.

In the above configuration, a warning display may be incorporated in the display image.
By doing so, a warning is also displayed on the combiner or the windshield glass, so that the driver can know the contents of the warning while facing the front.

Further, in the above configuration, it is possible to provide a configuration having a function of changing the luminance of a part or the whole of the display content. Under such a configuration, if the difference between the luminances is increased, the on / off state can be relatively realized when the luminance is high and when the luminance is low.

Further, in the above configuration, it is possible to provide a configuration having a function of blinking a part or the whole of the display content (claim 8). This blinking operation can be realized by periodically changing the luminance, so that the driving vehicle can be further alerted.

Further, in order to surely inform the driver of the warning content as one of the above-mentioned problems, the present invention provides the warning content on a combiner or windshield glass arranged on the driver side facing the windshield glass. This is displayed (claim 9). By doing so, the projected image on the combiner or the windshield glass becomes an enlarged image, so that the recognition is high and the warning effect is enhanced.

[0018]

Embodiments of the present invention will be described below with reference to the drawings. In this embodiment, a case where the display conventionally performed on an instrument panel is performed by a fluorescent display tube of front and back display on two sides will be described as an example, but another display such as a liquid crystal display device may be used.

As shown in FIG. 1, a general fluorescent display tube heats a phosphor 53 in a grid 52 by a filament 51 disposed inside the display tube, and the phosphor 53
The character / symbol (segment 54) is drawn by the light emission of.

As shown in FIG. 2, the two-display fluorescent display tube used in this embodiment has, as shown in FIG. 2, a grid 2 in which a fluorescent substance 3 is sealed and arranged on both front and back surfaces of the display tube to form a segment 4 for forming a display image. Can be directly viewed from outside the fluorescent display tube 10. When the front and rear segments 4 are directly viewed from the respective directions, they are in a mirror image relationship with each other. Therefore, if the display image formed by one segment 4 is inverted by the reflection mirror, the other display image can be obtained. 1 in the figure
Is a filament, 5 is a glass substrate, and 6 is a lead wire.

In this embodiment, the above principle is used, and FIG.
As shown in FIG. 4 and FIG. 4, the side displaying the display form (hereinafter referred to as “normal display”) whose contents can be read normally when the driver looks directly at the front screen 11 of the fluorescent display tube 10,
The side on which the mirror image of the normal display appears is the rear screen 12. Then, the mirror image displayed on the back screen 12 is inverted by the reflection mirror 13 and the lens 16, and the image which has become the normal display is projected onto the projection surface 15 of the combiner 14. In this way, the normal display can be directly viewed on both the virtual image I illuminated on the projection surface 15 of the combiner 14 and the real image on the front screen 11 of the fluorescent display tube 10.

Further, as shown in FIG.
The display image of the front screen 11 is also
By using 3 to see the virtual image, the image can be magnified and viewed, and the focal point can be set at a distant place.

The WG shown in FIGS. 3, 4 and 5
Is a windshield glass, B is a car body, and P is an instrument panel.

As described above, in this embodiment, the conventional system using an expensive HUD-dedicated display device and an instrument panel is replaced by a generally-used inexpensive fluorescent display tube 10 and reflecting mirror 13. As a result, it is possible to construct an extremely inexpensive HUD system while having the same function as the conventional one.

To switch between display and non-display on the combiner 14, the reflectance of the reflection mirror 13 may be changed. In this embodiment, as shown in FIGS. A liquid crystal film 17 is attached to one surface of the reflection mirror 13, and the reflectance of the reflection mirror 13 can be adjusted by changing the light transmittance of the liquid crystal film 17.

In this embodiment, as shown in FIGS. 4 and 5, a liquid crystal shutter 18 can be provided on the display surfaces 11 and 12 of the fluorescent display tube 10.
According to this method, partial display / non-display switching of the display screen can be performed.

[0027] Thus, by hiding a display having a small necessity and displaying only a high necessity, it is possible to improve the recognition and warning of the display contents having a high necessity. Can be. When the non-displayed one becomes necessary, it can be immediately switched to the display state. With a conventional mechanical pointer, such display screen cannot be partially switched between display and non-display.

The liquid crystal shutter 18 is of a TN (Twisted Nematic) type using a polarizing plate, and a polymer is dispersed in liquid crystal molecules, and light transmittance of the liquid crystal is increased by utilizing light scattering of the liquid crystal by the polymer. There is a light scattering type that changes. A light scattering type liquid crystal shutter 18 having a small loss is preferable because a polarizing plate using a polarizing plate has a large loss at the time of transmission due to light absorption of the polarizing plate. By the way, T
In the N type, there is usually a loss of about 50%, and in the light scattering type liquid crystal shutter 18, it is about 20%.

In the adjustment of the light transmittance of the liquid crystal film 17, not only the on / off display / non-display switching as in the liquid crystal shutter 18 but also the light transmittance of the liquid crystal film 17 is determined. It can be set to a level between completely non-transparent and the brightness of the projected image can be adjusted, so make the difference in the brightness of the projected image day and night so that you can see the image with the brightness suitable for each situation be able to.

Conventionally, the contents displayed on the combiner 14 have been limited to speedometers, fuel gauges, and the like which are frequently seen during traveling. However, in this embodiment, not only these measured values but also conventional values are used. The content of the warning display displayed on the instrument panel (see FIG. 8) shown in the example is also incorporated. Table 1 below shows all of the display contents including the warning display.
To list.

[0031]

[Table 1]

As described above, the warning display content is also displayed on the combiner 14, so that warning information is issued on both the fluorescent display tube 10 and the combiner 14, so that the projection of the combiner 14 is performed to secure a wide field of view. Even if the surface 15 is turned down, the warning display is also performed on the front screen 11 side of the fluorescent display tube 10, so that the driver can always see the warning display.

Further, as an operation of the display, the display at the time of the warning is forcibly made as shown in FIG.
If only the virtual image I on the projection plane 15 of FIG. 4 is used, the driver can be alerted more. For that purpose, the brightness of the front screen 11 of the fluorescent display tube 10 is reduced, and the brightness of the rear screen 12 is increased. If you do this,
Back screen 12 displayed on projection surface 15 of combiner 14
Is brighter than the brightness of the front screen 11 of the fluorescent display tube 10, so that only the virtual image I on the projection surface 15 of the combiner 14 is relatively displayed. It is in the same state as the above.

At this time, as shown in FIG.
In the display contents displayed on the projection surface 15 of FIG. 4, if the brightness of the warning portion is made brighter than the surroundings to make it stand out, the warning portion and the surroundings are turned on and off relatively, further increasing the warning effect. . Then, by periodically changing the luminance, a blinking operation can be realized. The warning contents marked with * in the above Table 1 are particularly important warning contents. Therefore, at the time of the warning, the part may be flashed to draw the driver's attention.

The display on the front screen 11 of the fluorescent display tube 10 for real image display is also performed by periodically changing the luminance.
In addition, the period can be changed to draw the driver's attention.

It should be noted that the warning display is performed only on the projection surface 15 of the combiner 14 located above the instrument panel P, because the instrument panel and the H
The present invention can also be applied to the case of a system using a UD-dedicated display device, in which case the warning display content is incorporated in the HUD-dedicated display device.

Up to now, the display has been performed by the combiner 14.
Has been discussed in the form of performing on the projection surface 15 of the above, but if the combiner 14 is abolished and displayed directly on the windshield glass WG, the reflection of the window of the combiner 14 on the windshield glass WG, The complicated wiring of the combiner 14 on the instrument panel P can be prevented from having a poor appearance.

[0038]

As described above, according to the present invention, instead of the conventional instrument panel, a display device in which the display image can be viewed directly from the front and back as a real image is used, and can be read normally when the driver looks directly at the display device. The side showing the display form (normal display) is the front screen of the display, the side on which the mirror image of the normal display is displayed is the back screen, and the mirror image appearing on the back screen is reflected by the reflecting mirror to be on the combiner or windshield glass. , It is possible to construct a much cheaper HUD system while satisfying the same function as the conventional one, in which the normal display can be directly viewed both on the combiner or windshield glass and on the front screen of the display. .

By displaying important display contents such as a warning display on the combiner or the windshield glass, there is no change in the field of view and no change in the focus, so that the safety during traveling is enhanced.

[Brief description of the drawings]

FIG. 1A is a perspective view of a main part including a partial cross section,
FIG. 2B shows a general fluorescent display tube showing a cross section taken along line AA in FIG.

FIG. 2 is a cross-sectional view of a dual display fluorescent display tube used in the embodiment.

FIG. 3 is a diagram showing the principle of the embodiment.

FIG. 4 is a diagram showing the operation of the embodiment;

FIG. 5 is a diagram showing the operation of the embodiment;

FIG. 6 is a diagram showing the operation of the embodiment;

FIG. 7 is a diagram showing the operation of the embodiment;

FIG. 8 is a diagram showing an example of an instrument panel of an automobile.

FIG. 9 is a schematic diagram showing a defect of the conventional example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Filament 2 Grid 3 Phosphor 4 Segment 10 Fluorescent display tube 11 Front screen 12 Back screen 13 Reflection mirror 14 Combiner 15 Projection surface 16 Lens 17 Liquid crystal film 18 Liquid crystal shutter

 ──────────────────────────────────────────────────続 き Continuing from the front page (72) Inventor Yasue Matsumoto 1-7-10 Kikuzumi, Minami-ku, Nagoya City Inside Harness Research Institute, Inc. (72) Inventor Yozo Nishiura 1-7-7 Kikuzumi, Minami-ku, Nagoya City 10 Harness Research Institute, Inc. (72) Inventor Kensaku Takada 1-7-10 Kikuzumi, Minami-ku, Nagoya-shi Harness Research Institute, Inc.

Claims (9)

[Claims] 1. A display device of a vehicle for projecting a display image displayed on a display device onto a combiner or a windshield glass disposed on a driver side facing a windshield glass, wherein the display device displays the display image. Is directly visible from the front and back, the display image on the front side is directly visible to the driver, the display image on the back side is inverted via an optical member, and the inverted image is displayed on the combiner or windshield glass. A display device for a vehicle, wherein the display device performs projection. 2. The method according to claim 1, wherein a reflection mirror is used as the optical member, and switching between the projection and non-projection of the inverted image is performed by changing the reflectance of the reflection mirror. Vehicle display device. 3. The reflection mirror according to claim 2, wherein a liquid crystal film is provided on the reflection surface of the reflection mirror, and the reflectance of the reflection mirror is changed by changing the light transmittance of the liquid crystal film. The display device for a vehicle according to any one of the preceding claims. 4. The liquid crystal shutter according to claim 1, wherein a liquid crystal shutter is provided on a display surface of the display, and switching between display and non-display is performed by the liquid crystal shutter. Display device of vehicle. 5. The display device according to claim 4, wherein said liquid crystal shutter is a light scattering type liquid crystal shutter. 6. The vehicle display device according to claim 1, wherein a warning display is incorporated in the display image. 7. The vehicle display device according to claim 1, further comprising a function of changing a luminance of a part or the whole of the display content. 8. The vehicle display device according to claim 1, further comprising a function of blinking part or all of the display content. 9. A display device for a vehicle, wherein a warning display is displayed on a combiner or windshield glass arranged on the driver side facing the windshield glass.