JP3747098B2 - Head-up display - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a head-up display suitable for being mounted on a vehicle such as a vehicle or a ship.
[0002]
[Prior art]
For example, a head-up display that provides navigation information to a vehicle driver includes a combiner disposed in front of the observer, an image display that emits image display light, and a housing that has an exit opening that opens upward. Is used. By changing the optical path of the image display light emitted from the housing through the emission port by the combiner, a virtual image to be observed is formed in front of the combiner. In addition, the scenery in front of the combiner can be visually recognized by the light transmitted through the combiner.
[0003]
[Problems to be solved by the invention]
It is desirable that the emission port be covered with a transparent cover in order to protect the image display and the like inside the housing from dust and the like.
[0004]
When the optical path of the image display light emitted from the image display is directly changed by the combiner, the optical path length of the image display light from the image display to the observer's pupil is shortened, and the distance from the observer to the virtual image formation position is reduced. Shorter. If it does so, time will be required until it recognizes a virtual image from the state which is gazing at the actual scenery ahead of a vehicle, and it is not desirable on driving. Further, if the distance between the image display and the combiner is increased in order to increase the optical path length, the head-up display becomes larger. Therefore, an optical path changing means such as a mirror for changing the optical path of the image display light may be provided below the transparent cover so that the image display light travels obliquely forward and upward after being emitted from the exit. desired.
[0005]
However, when the exit port is covered with a transparent cover and an optical path changing means is provided below the transparent cover, a virtual image called a ghost may be generated in addition to the virtual image to be observed. That is, when the image display light emitted from the image display device is directly changed in optical path by the optical path changing means below the transparent cover, the original observation is performed by changing the optical path of the image display light whose optical path has been changed by the combiner. A virtual image of the object is formed. However, as shown in FIG. 5, after a part of the image display light L emitted from the image display 101 is reflected by the lower surface side of the transparent cover 102, the optical path is changed by the optical path changing means 103, and the optical path is changed. When the displayed image display light is changed in optical path by the combiner 104 and reaches the pupil of the observer E, there is a problem that a ghost is formed and the visual recognition of clear display is hindered. There is also a problem that external light such as sunlight reflected by the upper surface side of the transparent cover 102 after passing through the combiner 104 reaches the observer E's pupil.
[0006]
[Means for Solving the Problems]
The present invention comprises a combiner disposed in front of the observer, an image display that emits image display light toward the rear, a housing having an exit opening that opens upward, and a transparent cover that covers the exit opening. The optical path of the image display light emitted from the housing through the emission port is changed by the combiner, so that the present invention is applied to a head-up display capable of forming a virtual image to be observed in front of the combiner.
[0007]
The present invention provides an optical path changing means for changing the optical path of the image display light emitted backward from the image display so that the image display light advances obliquely upward and forward after the image display light is emitted from the emission port. The image display light that is provided below the transparent cover and is reflected on the lower surface side of the transparent cover and then changed in the optical path by the combiner through the optical path changing means reaches below the front visual field range of the observer. In addition, the relative arrangement of the transparent cover with respect to the image display and the optical path changing means is defined.
Thereby, since the image display light reflected on the lower surface side of the transparent cover does not reach the front visual field range of the observer, it is possible to reliably prevent the ghost from being visually recognized by the observer .
[0008]
Further, the present invention provides an optical path changing means for changing an optical path of the image display light emitted backward from the image display so that the image display light advances obliquely upward and forward after the image display light is emitted from the emission port. Is provided below the transparent cover, and is reflected so that the image display light whose optical path is changed by the optical path changing means after being reflected on the lower surface side of the transparent cover reaches below the transparent cover. The second feature is that the relative arrangement of the image display and the optical path changing means is determined.
Thereby, since the image display light reflected on the lower surface side of the transparent cover does not reach the combiner, it is possible to reliably prevent the ghost from being formed.
[0009]
It is preferable that a cover capable of blocking outside light reflected by the upper surface side of the transparent cover after passing through the combiner so as not to reach the observer's pupil is preferably provided.
Thereby, it is possible to prevent external light reflected on the upper surface side of the transparent cover from reaching the observer's pupil.
[0010]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[0011]
FIGS. 1, 2 (1), 2, and 3 show the vehicle head-up display 1 according to the first embodiment, which includes a combiner 2, an image display 3, and the image display 3. A housing 5 having an emission port 5a that opens upward and a transparent cover 9 that covers the emission port 5a are provided. The upper and lower surfaces of the transparent cover 9 are inclined so as to go upward as it goes forward.
[0012]
The combiner 2 is provided on the front side of the upper portion of the housing 5 (left side in (1) and (2) of FIG. 2) so as to be rotatable about the left and right rotation shaft 6a via a hinge 6. By attaching the housing 5 to the upper surface of the dashboard, for example, the combiner 2 and the image display 3 are arranged in front of the driver (observer).
[0013]
As the combiner 2, for example, a plate-shaped half mirror, a hologram element, or the like can be used. When a half mirror is used, the optical path of light is changed by reflection, and when a hologram element is used, the optical path of light is changed by diffraction.
[0014]
The image display 3 emits image display light L corresponding to, for example, navigation information. As this image display 3, for example, a liquid crystal display having a backlight as a light source can be used, and a display that displays an image with a fluorescent display tube, LED, CRT, etc. that does not require a backlight is used. You can also.
[0015]
The image display 3 emits image display light L backward, and a mirror 8 that changes the optical path by totally reflecting the image display light L is built in the housing 5 below the transparent cover 9. The front reflecting surface of the mirror 8 is inclined so as to go backward as it goes upward. By changing the optical path of the image display light L by the reflection by the mirror 8, the image display light L is emitted from the emission port 5a so as to travel obliquely upward and forward.
[0016]
The combiner 2 rotates about the left and right rotation shaft 6a, thereby changing the optical path of the image display light L emitted from the emission port 5a as shown in FIG. As shown in (2) of FIG. 2, it is possible to displace between the use position leading to the storage position and the storage position for closing the front side of the emission port 5a. In the present embodiment, the position of the observer E is indicated by the position of the pupil.
[0017]
By changing the optical path of the image display light L by the combiner 2, a virtual image to be observed is formed in front of the combiner 2. As a result, the driver can visually recognize both the virtual image and the object actually present in front. The optical path changing surface 2a of the combiner 2 has a function of condensing the image display light L, and is a curved surface capable of forming the virtual image farther forward than simple reflection.
[0018]
The image display 3 and the mirror of the transparent cover 9 so that the image display light L whose optical path is changed by the mirror 8 after being reflected on the lower surface side of the transparent cover 9 travels downward from the transparent cover 9. The relative arrangement with respect to 8 is determined. That is, as shown in FIG. 3, the image display light L is reflected on the lower surface side of the transparent cover 8, and then the optical path is changed by the mirror 8, thereby proceeding downward from the transparent cover 9.
[0019]
A movable cover 12 is provided on the upper rear side of the housing 5 between the combiner 2 and the observer E. The movable cover 12 has a plate-like upper surface portion 12a, a back surface portion 12b extending downward from the rear edge of the upper surface portion 12a, and a side surface portion 12c extending downward from the rear side of the left and right side edges of the upper surface portion 12a. And it is attached to the housing 5 through the side surface portion 12c so as to be rotatable about the left and right rotation shaft 12d. The movable cover 12 rotates about the rotation axis 12d, and as shown in (1) of FIG. 2, the open position that does not block the image display light L toward the pupil of the observer E and ( As shown in 2), it is displaced between the position where the rear side of the exit port 5a is closed so as to block a part of the image display light L toward the pupil of the observer E.
[0020]
The movable cover 12 in the open position, as shown by a one-dot chain line in FIG. 3, transmits external light R such as sunlight reflected by the upper surface side of the transparent cover 9 after passing through the combiner 2 to the pupil of the observer E. It can be blocked so that it does not reach. The external light R that is not blocked by the movable cover 12 has a large incident angle on the upper surface of the transparent cover 9 and therefore has a large reflection angle. To the observer E's eyes.
[0021]
According to the above configuration, since the image display light L reflected on the lower surface side of the transparent cover 9 that prevents dust and the like from entering the housing 5 from the emission port 5a does not reach the combiner 2, a ghost is generated. It is possible to reliably prevent the formation. Further, it is possible to prevent the external light R reflected on the upper surface side of the transparent cover 9 from reaching the observer E's pupil. Thereby, in the small head-up display 1 that can display a virtual image to be observed at an appropriate front-and-rear position and prevent internal entry of dust or the like, the visual recognition of a clear display virtual image is hindered by the occurrence of ghost or external light. Can be prevented.
[0022]
FIG. 4 shows a second embodiment of the present invention. The difference from the first embodiment is that the upper and lower surfaces of the transparent cover 9 slightly move downward as they move forward. Further, the image display 3 and the transparent cover 9 are close to each other as compared with the first embodiment. In this case, the image display light L is reflected on the lower surface side of the transparent cover 9 and then the optical path is changed by the mirror 8, thereby reaching the combiner 2 through the transparent cover 9 and the optical path being changed by the combiner 2. It goes backwards. A part of the image display light L traveling rearward is blocked by the movable cover 12, and the remaining part travels rearward and reaches below the observer E's front visual field range. In this case, a ghost is formed, but the image display light L reflected on the lower surface side of the transparent cover 9 does not reach the pupil of the observer E, so that the ghost is prevented from being visually recognized by the observer E. it can. Furthermore, the head-up display 1 can be miniaturized by shortening the distance between the image display 3 and the transparent cover 9 as compared with the first embodiment. In the second embodiment, external light such as sunlight that has passed through the combiner 2 and is reflected by the upper surface side of the transparent cover 9 reaches the pupil of the observer E without being blocked by the movable cover 12. It is suitable for use at night without the influence of outside light. Others are the same as in the first embodiment, and the same parts are denoted by the same reference numerals.
[0023]
In addition, this invention is not limited to the said embodiment. For example, the head-up display according to the present invention may be mounted on a vehicle other than a vehicle, and the content of the display image is not limited to navigation information.
[0024]
【The invention's effect】
According to the present invention, in a small head-up display that can display a virtual image of an observation target at an appropriate position and prevent internal entry of dust or the like, the visibility of a clear display virtual image is hindered by the occurrence of ghost or external light. Can be prevented.
[Brief description of the drawings]
FIG. 1 is a perspective view of a head-up display according to a first embodiment of the present invention. FIG. 2 is an explanatory diagram of use of the head-up display according to the first embodiment of the present invention, and FIG. FIG. 3 is a diagram showing an optical path of image display light of the head-up display of the first embodiment of the present invention. FIG. 4 is an optical path of image display light of the head-up display of the second embodiment of the present invention. FIG. 5 is a diagram showing an optical path of image display light of a head-up display of a comparative example.
2 Combiner 3 Image display 5 Housing 5a Outlet 8 Mirror 12 Movable cover E Observer L Image display light

Claims (3)

A combiner placed in front of the observer;
An image display that emits image display light toward the rear ;
A housing having an exit opening that opens upward;
With a transparent cover covering the exit,
In the head-up display capable of forming a virtual image of the observation object in front of the combiner by changing the optical path of the image display light emitted from the housing through the emission port by the combiner.
An optical path changing means for changing an optical path of the image display light emitted backward from the image display so that the image display light travels obliquely upward and forward after the image display light is emitted from the emission port. Provided below,
An image display device for the transparent cover so that the image display light that is reflected on the lower surface side of the transparent cover and then the optical path is changed by the combiner through the optical path changing means reaches below the observer's front visual field range . A head-up display characterized in that a relative arrangement with respect to the optical path changing means is determined. A combiner placed in front of the observer;
An image display that emits image display light toward the rear;
A housing having an exit opening that opens upward;
With a transparent cover covering the exit,
In the head-up display capable of forming a virtual image of the observation object in front of the combiner by changing the optical path of the image display light emitted from the housing through the emission port by the combiner.
An optical path changing means for changing an optical path of the image display light emitted backward from the image display so that the image display light travels obliquely upward and forward after the image display light is emitted from the emission port. Provided below,
Image display light to be changed more optical path to the optical path changing hands stage after being reflected at the lower surface side of the transparent cover, so as to reach below the its transparent cover, an image display device and the optical path changing means of the transparent cover A head-up display characterized in that a relative arrangement with respect to is defined. The head-up display according to claim 1 or 2, further comprising a cover capable of blocking outside light reflected by the upper surface side of the transparent cover after passing through the combiner so as not to reach the observer's pupil .

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