JPS62173336A - Head-up display device for vehicle mount - Google Patents

Abstract

PURPOSE:To obtain a clear, high quality display image by arranging an optical device for reflecting a virtual image of a display image to a driver thereby correcting parallax of the virtual image incident on the right and left eyes of the driver. CONSTITUTION:A prism 30 is of a cross section with its upper surface only sloped, thicker toward the vehicle front side, and its vertical angle made varied greater on the left side. Using this prism 30, a light beam coming out of an optical device 12 and tending through a windshield to a left eye is corrected: the light beam KL' tending to the left eye is refracted by an angle of theta to be corrected, reflected at a point B' of a same height with a reflection point A where a light to the right eye is reflected, and tends of the left eye. This makes vertical parallax eliminated and makes a driver recognize a clear, high quality display image without his field of view through the windshield being obstructed.

Description

[Detailed Description of the Invention] [Summary of the Invention] In an in-vehicle head amplifier display device that uses the windshield of an automobile as a reflective optical system and projects a display image in front of the windshield, a head amplifier display device that is placed between the optical system and the windshield is used. By providing an optical means for correcting the parallax between the virtual images facing the left and right eyes of the driver, the binocular parallax is corrected when the virtual image of the displayed image is reflected by the windshield, so that the driver does not have to worry about his or her eyes. without forcing you to adjust the
To visually recognize a clear and high-quality display image.

[Industrial application field]

The present invention relates to an in-vehicle handpiece display device,
More specifically, the present invention relates to an in-vehicle doorknob display device that utilizes the windshield of an automobile to display various information using a virtual image optical system.

[Conventional technology]

2. Description of the Related Art Devices have been proposed that display information such as the speed, time, and engine speed of a vehicle by forming a virtual image in front of the windshield using internal reflections of the windshield. Such a device is called an in-vehicle head-up display device (hereinafter referred to as HUD).

FIGS. 5 and 6 show the basic structure of a HUD that has been proposed in the past. As shown in FIG. 5, the apparatus is comprised of a display device 11 incorporated in the center of the dash board, a (refractive) optical system 12 such as a lens, and a reflective optical system using a windshield 13. The display device is LED,
Using an LCD or the like, a small image on a display is magnified by a virtual image optical system consisting of an optical system 12 and a windshield 13 and formed as a virtual image in front of the windshield 13.

Therefore, as shown in FIG. 6, the driver perceives the virtual image display (displaying speed in this case) on the display device 11 of the HUD as if it were present at a predetermined distance in front of the vehicle 14.

[Problem that the invention seeks to solve]

2. Description of the Related Art Techniques for forming image information such as display information using LEDs, LCDs, etc., and image information such as field frames within a predetermined optical field of view have long been used in camera finders and the like. HUD
This technology is basically the same as this display technology, but in the case of a HUD, there is a problem to be solved in that a windshield is used for the reflective optical system.

This is a problem of binocular parallax caused by the direction of reflection from the windshield.

That is, as shown in FIG. 7, when the HUD unit 1 consisting of a display device and an optical system is placed at the center of the dash board and a virtual image is reflected toward the driver seated on the right seat of the automobile, As shown in FIG. 8, the reflection points 19 and 19 on the windshield of the same virtual image that reach the driver's right eye 16R and left eye 16L end up at different positions due to the parallax between the left and right eyes.

Figure 9 shows driver's eyes 16R, 16L, HUD unit (
Object point 1') and the position of the reflection point on the windshield are shown from above.

Here, for ease of explanation, the fronton 5'' lath is assumed to be a flat glass, and problems in setting the following conditions will be described.

゛For example, in Figure 9, the average distance between the left and right eyes L
1 is about 70 fins, and the distance 81' along the longitudinal direction of the car from the center position of the eyes 16L and 16R to the midpoint 19' of the reflection points of the left and right eyes on the windshield is about 850 m. Also,
As shown in FIG. 10, the virtual image is incident on the HUD unit 1 from below the eye, and the height difference H between the midpoint 19' of the reflection point and the eye is approximately 30u+. Furthermore, the distance L2 from the line passing through the midpoint 19' of the reflection point along the longitudinal direction of the car to the center of the eye is approximately 2104 m. Further, it is assumed that the windshield has an inclination of 28 degrees with respect to the horizontal plane at the midpoint 19' of the reflection point.

That is, the HUD unit allows light to enter the windshield from the lower left front (in the case of a right-hand drive vehicle), and the reflected light travels from the reflection point to the upper right eye.

Under these conditions, the reflection point 19L of the left eye is the reflection point 1 of the right eye with respect to the plane formed by the y-axis along the vertical direction and the Z-axis along the left-right direction of the car, as shown in FIG.
The position is shifted to the lower left from 9R. Under the above conditions,
When reflecting points 19L and 19R are projected onto the yz plane, the height difference is 7.51 m, and the left-right difference is 66.5 fins.

In Figure 9, the distance 31' (850 mm) from the center of the eye to the reflection point measured in the longitudinal direction of the car, the height difference H (301 m) between the eye and the center 19' of the reflection point, and the center of the eye and the reflection point. From the condition of distance L2 (210 m) of a line passing through the center of The binocular disparity θ (= jan−'
(7,5/876)) becomes 0.49'.

Therefore, depending on the size of the image in the horizontal direction, the image reflected by the windshield becomes a double image due to the binocular parallax as described above. Basically, the human eye is not good at adjusting the left and right eyes in the vertical direction, and if the same image is incident on the left and right eyes for a long time with the above parallax, it can cause eye strain. This is a big problem from the standpoint of preventing danger. Regarding the above binocular parallax, the top and bottom of the windshield,
Although we did not consider the curvature in the left-right direction, if the curvature is taken into account, the deviation of the virtual image will become larger.

As mentioned above, when using a windshield as a reflective means, there is a problem of parallax, and unless this problem is solved,
It is not possible for a driver to view a clear display image without causing eye strain.

[Means for solving problems]

In order to solve the above problems, the present invention uses the windshield of an automobile as a reflective optical system and provides a display for displaying various information in an in-vehicle head amplifier display device that projects a display image in front of the windshield. means, an optical system for causing a virtual image of the display image of the display means to enter the windshield and reflecting it toward the driver; and an optical system disposed between the optical system and the windshield to direct the virtual image to the right and left eyes of the driver. A configuration including optical means for correcting parallax was adopted.

[For production]

According to the above configuration, when the virtual image of the display image is reflected by the windshield, binocular parallax is corrected, so a clear and high-quality display image can be displayed without forcing the driver to make forced eye adjustments. It can be visually recognized.

〔Example〕

Hereinafter, the present invention will be described in detail based on embodiments shown in the drawings.

Regarding windshields, we will explain the technology to prevent binocular parallax.

In the conventional example section, under the condition settings shown in relation to FIGS. 8 and 9, the deviation of the reflection point of the HUD light image incident on the left and right eyes on the windshield is 66.5 in the left-right direction.
It has been stated that the vertical direction of the dragon is approximately 7.51, and the vertical parallax θ at that time is 0.496.

As can be seen from the fact that stereoscopic vision is obtained by the horizontal parallax between the left and right eyes, the difference in the left-right direction among the above differences does not pose much of a problem even without correction. Therefore, by correcting only the vertical parallax between the left and right eyes, a satisfactory display image can be obtained even when reflection is performed diagonally.

Therefore, in FIGS. 8 and 9, if the reflection point for the left eye, which is 7.5 mm lower than that for the right eye, is moved upward, the vertical parallax will be eliminated and the displayed image should become considerably easier to see.

To this end, in this embodiment, as shown in FIG. 1, a prism 30 is used to correct the movement of the light beam that exits the optical system 12 of the HUD unit and travels to the left eye via the windshield. In Figure 1, the HU in the height direction of the dash board
In order to reduce the size of the D unit, the image on the display 11 is reflected once by the mirror 1a before entering the optical system 12.

FIG. 2 shows the action of the prism 300 in detail. In the figure, the symbol KL is the light beam heading toward the left eye before correction, and the light beam KR heading toward the right eye is reflected at a reflection point B lower than the reflection point A, and is reflected back to the left eye. Head towards.

The angle θ between the two light beams after reflection is the vertical parallax.

As shown in FIG. 3, the prism 30 has a cross-sectional shape in which only the upper surface is inclined, and is thicker on the front side of the vehicle body. Further, the apex angle of the prism is varied so that it is large on the left side, where the light beam heading toward the left eye passes, and becomes small on the right side, where the light flux heading toward the right eye passes, so that the upper surface of the prism has a curved shape.

When a virtual image of a display image is projected through such a prism with the settings shown in connection with FIGS. 8 and 9, the light beam heading toward the left eye is moved as indicated by the symbol KL'.

That is, the prism cross section shown in FIG. 2 is a cross section through which the light beam KL heading toward the left eye passes, and the light beam KLl heading toward the right eye passes through a cross section corresponding to the back of the figure (to the right of the vehicle body) from this cross section. In the cross section through which the light beam KR passes, the apex angle of the prism 30 is smaller, and the light beam KR passes through substantially the same position as in the case without prism correction. On the other hand, the light beam KL' passes through a cross section with a larger apex angle, is refracted by the angle θ to be corrected, is reflected at a point B' having the same height as the reflection point A of the right eye, and heads toward the left eye.

As mentioned above, due to the action of the prism, the windshield 1
Both light beams KL'+KR heading from 3 to the eyes pass 1 jrl through the horizontal plane including the left and right eyes, eliminating parallax in the vertical direction, making it possible to obtain an easy-to-see image without vertical binocular parallax. However, in the above action G, since the angle of inclination of the light beam KL'KR before being reflected by the windshield is different, the directions of the perpendiculars Bv and AV at the reflection point B' and AJ are naturally different.

Here, an example of a prism shape for eliminating the binocular parallax of 0.496 will be specifically explained using FIG. 3. First, the effective diameter of the lens of the optical system (Φ120), the horizontal distance G of the reflection point A (!:B) is 66°5*1.
When magnified by 80 times, the width bL of the prism 30 is required to be about 130 mm, and the depth a is 53 mm from the aspect ratio of the displayed image.
It will be about. Further, the prism 30 has a bottom surface perpendicular to the optical axis of the optical system 12, and its thickness L is 1.0 mm. The refractive index n of the power glass used in the prism is 1.49.
Set it to 2.

In FIG. 3, the maximum apex angle θ on the X axis. The required refraction angle for the refractive index n is θ=5in-' (n sin θ.)-θ. (-0,
49°)... (1) and the angle change θ in the long side direction of the prism 30.

is θt-1,80θ. Then, by transforming equation (1), 5in0.49°1.492-coso,49' Therefore, θ. −1.0°, θt =1.8° is obtained.

Since the height and thickness (Z) of the prism 30 are shown as As can be seen from the figure, the prism 30 has a curved upper surface so that it is thicker at the front left side and thinner at the front right side.

As described above, it is possible to eliminate the vertical binocular parallax that occurs when the driver's eyes and the driver's eyes are diagonally reflected from the HUD to the windshield. The displayed image can be visually recognized. Although the curved shape of the windshield was not considered in Figures 3 and 4, if the windshield is curved, especially if it has a large curved surface in the left and right direction, it is possible to reflect the curvature in the prism shape. Display images without parallax can be obtained.

In the above embodiment, the mirror 1a is provided between the display 11 and the optical system 12, but this may be omitted so that the display 11 can be placed on the optical axis of the optical system 12. .

〔Effect of the invention〕

As is clear from the above description, according to the present invention, in an in-vehicle head-up display device that uses the windshield of an automobile as a reflective optical system and projects a display image in front of the windshield, a display for displaying various information is provided. means, an optical system for causing a virtual image of the display image of the display means to enter the windshield and reflecting it toward the driver; and an optical system disposed between the optical system and the windshield to direct the virtual image to the right and left eyes of the driver. The structure is equipped with optical means to correct parallax, so the driver can see a clear, high-quality display image without impairing the visibility of the windshield, and it also reduces eye strain for the driver. It is possible to provide an excellent in-vehicle head-up display device that can impart high driving performance and safety to the vehicle in which it is installed without causing any problems.

[Brief explanation of drawings]

1 to 4 show an embodiment of the HOD according to the present invention. Fig. 3 is a perspective view of the prism shown in Fig. 1, Fig. 4 is a line diagram explaining the shape of the prism shown in Fig. 1, and Fig. 5 and subsequent figures show the conventional structure. Fig. 5 is an explanatory diagram showing the basic structure of the HUD, Fig. 6 is an explanatory diagram showing the projection of the displayed image, and Figs. 7 to 11 are explanatory diagrams showing the binocular parallax in the HUD. It is a diagram. 1...HOD unit, 11...display device, 12.
...optical system, 13...windshield, 16...eye, 30...prism. Patent Applicant: Yazaki Sogyo Co., Ltd. ■、Indication of the case 1985 Patent Application No. 011123 2゜2、Name of the invention
3. Relationship with the case of the person making the amendment Patent applicant address: 1-4-28-3, Mita, Minato-ku, Tokyo Name (689) Yazaki Sogyo Co., Ltd. 4, Agent 8, Amendment Contents of heavy industry (Japanese Patent Application No. 1981-011123) The formula on page 12, line 4 of the specification is corrected as follows. The formula on page 12, line 11 of Librarian is corrected as follows: +1.0
(3) Replace Figure 4 with the attached drawing.

Claims (1)

[Claims] 1) Using an automobile windshield as a reflective optical system,
An in-vehicle head-up display device that projects a display image in front of the windshield includes a display means for displaying various information, and an optical system that causes a virtual image of the display image of the display means to be incident on the windshield and reflected toward the driver. An in-vehicle head-up display device comprising: a head-up display system; and an optical means disposed between the optical system and a windshield to correct parallax of the virtual image facing the left and right eyes of a driver. 2) The in-vehicle head according to claim 1, wherein the correction optical means comprises a prism and corrects the height of a reflection point of a reflected light beam of a virtual image directed toward the left and right eyes of the driver. up display device.