JPH04317827A - Vehicle indicator - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

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 disposed on an instrument panel surface, and more particularly to a vehicle display device in which a dial displaying characters, scales, etc. is composed of a hologram.

0002

2. Description of the Related Art Conventionally, as a typical analog display device for a vehicle such as a speedometer or a tachometer, the one shown in FIG. 6 has been used. FIG. 6 is a cross-sectional view of the side surface of the speedometer. A pointer 22 is placed in front of a dial 21 that displays characters and scales for speed, rotational speed, etc., and a pointer 22 is placed behind the dial 21. A driving section (not shown) for driving the pointer 22 is provided. The drive unit is activated by signals from sensors placed in various parts of the vehicle.
The pointer 22 is designed to indicate a predetermined position of characters, scales, etc. on the dial 21.

[0003] The dial 21 is made of a light-opaque material, and portions of the dial 21 such as letters and scales are transparent. Further, a light guide plate 23 is disposed in close contact with the back surface of the dial 21, and a light source 24 is installed close to the tip 23a of the light guide plate 23. When the light source 24 is turned on, the light emitted from the light source 24 travels within the light guide plate 23 by repeating reflections as shown by arrow A, and irradiates the back surface of the dial 21 with light. For this reason, from the driver's perspective, the characters and the light-transmitting part of the dial 21
Parts such as scales will shine and be visible.

[0004] Also, in FIG. 6, a meter hood 25 has an eave-like shape above the dial 21 to prevent light from outside the vehicle from directly hitting the dial 21 and washing out the display. belongs to. Further, in front of the dial 21, a front plate 26 made of transparent glass or plastic is attached in a downwardly curved manner from the tip of the meter hood 25.
This is to protect the dial 21, hands 22, etc. from dust and mechanical shock.

[0005] The reason why the front plate 26 is not arranged parallel to the surface of the dial 21 is that an object in front of the front plate 26 may be reflected on the dial 21 due to surface reflection. This is to try to prevent this.

[0006]

[Problems to be Solved by the Invention] However, as described above, the vehicle display device uses the meter hood 25 so that the dial 21 is not directly exposed to external light, and also uses the meter hood 25 so that the front plate 26 is placed above the surface of the dial 21. Because they are placed non-parallel to each other, extra space is required and the overall depth of the device becomes longer, requiring more installation space.Furthermore, the use of these devices imposes design limitations. I may receive it.

SUMMARY OF THE INVENTION An object of the present invention is to provide a meter hoodless vehicle display device that does not deteriorate display quality even when external light is incident and does not reflect objects in front of the front panel.

[0008]

[Means for Solving the Problems] A display device for a vehicle according to the present invention has a dial made of a hologram on which characters, scales, etc. are recorded, and behind the dial, light is irradiated onto the dial. At the same time, a pointer that is driven according to an input signal is arranged on the front surface of the dial, and a non-glare plate is arranged in front of the pointer, and when the light from the light source is irradiated onto the back surface of the dial. The dial is characterized in that display images such as letters and scales are formed at a position close to the back surface of the non-glare plate due to the light diffraction effect of the dial.

Further, the vehicle display device according to the present invention is characterized in that a louver having a light absorption surface in the horizontal direction is disposed adjacent to the back surface of the non-glare plate.

0010

[Operation] Based on the above-mentioned configuration, when the light source of the vehicle display device is turned on, the light hits the dial made of a hologram and is diffracted, resulting in the real images of characters, scales, etc. recorded in the hologram in advance. The image is formed close to the back of the non-glare plate. From the driver's perspective, the images of letters, scales, etc. formed by the hologram are seen through the non-glare plate, but since the images are close to the back of the non-glare plate, they can be seen with almost no blur. be done.

[0011] Furthermore, since a non-glare plate is used for the front plate that protects the dial, hands, etc., even if outside light enters, the display on the dial surface will wash out, or objects in front of the front plate may be washed out. will not be reflected on the front panel and become an eyesore.

Furthermore, in the case where a louver is placed adjacent to the back side of the non-glare plate, the zero-order light from the light source that passes through the hologram is absorbed and removed by the louver. Since the secondary light hits the non-glare surface of the non-glare plate and is diffused, the display area is not vaguely illuminated, so the display quality of display images such as letters and scales is maintained at a good level.

[0013]

Embodiments Hereinafter, embodiments of the present invention will be described based on the drawings.

FIG. 1 shows an embodiment of a vehicle display device according to the present invention, and is a cross-sectional view of the side surface of a speedometer. A hologram 2 is installed in a case 1, and a pointer 3 is placed in front of the hologram 2. The pointer 3 is rotationally driven by a drive unit (not shown), and stops at a position corresponding to a sensor signal attached to a rotating shaft such as a tire of a vehicle, and indicates a predetermined position of characters, scales, etc. to be described later. It has become.

Further, a non-glare plate 4 is disposed in front of the pointer 3 and exactly at the opening surface of the case 1. The non-glare plate 4 is made of a transparent plastic plate, and the front surface thereof is a non-glare surface 4a which has been subjected to a non-glare treatment, and the back surface is a smooth surface. Note that although this non-glare plate 4 is a plastic plate, a glass plate may be used instead.

A light source 5 for irradiating the hologram 2 with reproduction light RW is installed at the upper corner of the case 1 behind the hologram 2. When the hologram 2 is irradiated with reproduction light RW from the light source 5 in advance, the light is diffracted to form a real display image 6 of characters, scales, etc. at a position close to the back surface of the non-glare plate 4. information is recorded in. The display image 6 formed in this way is as if
At this position, a display image of characters, scales, etc. shows the same appearance as they would in reality, and a diverging light is emitted starting from this display image.

As is well known, when an image is viewed through a transparent plastic plate or the like that has been treated with non-glare, the distance d between the position of the image 10 and the non-glare treated surface 11 is as shown in FIG. If it is long, the image 10 will be difficult to see, Figure 3
As shown in FIG. 2, the image 10 is clearly visible when the distance d between the position of the image 10 and the non-glare surface 11 is short. This is because if part of the image 10 is considered as point light sources P1 and P2, if the distance d is long, the light emitted from the point light sources P1 and P2 will diverge, and the wavefront of the diverging light will reach the non-glare surface 11. When the light is incident, it is scattered by each minute unevenness of the non-glare surface 11, and the scattered light waves interfere with each other, so that the image cannot be clearly seen from the viewpoint 7. On the other hand, when the distance d is short, the light emitted from the point light sources P1, P2 enters the non-glare surface 11 before diverging, so when viewed from the viewpoint 7, the light emitted from the point light sources P1, P2 is almost seen as diverging. Therefore, the image 10 can be seen clearly.

For this reason, in this speedometer, as shown in FIG. 1, the position of the display image formed by the dial 2 irradiated with reproduction light from the light source 5 is set to a position close to the back surface of the non-glare plate 4. There is.

Next, another embodiment will be explained. The same members as those shown in the previous embodiment are denoted by the same reference numerals, and explanations thereof will be omitted.

As shown in FIG. 4, this vehicle display device includes a louver 12 having a new horizontal light absorbing surface adjacent to the back surface of the non-glare plate 4 of the speedometer shown in the previous embodiment. is arranged. The louver 12 is made of a transparent thin plastic film, and between the front and back sides of the film, dark-colored layers are formed at regular intervals and with a constant width, and the surface of the layer is a light-absorbing surface. , the louver 1
Of the light that attempts to pass through from the back surface to the front surface of 2, the light that has an incident angle greater than a certain angle hits the dark layer and is absorbed and cannot be transmitted.

The reason for arranging the louver 12 in this way is as follows.
As shown in FIG. 5, reproduction light R is transmitted from the light source 5 to the hologram 2.
When W is irradiated, a display image is formed close to the back surface of the non-glare plate 4 based on the information recorded in advance on the hologram 2, as explained in the previous embodiment. In addition to the first-order diffracted light that forms an image, the existence of zero-order light that passes through the hologram 2 as it is is recognized. Since the zero-order light that passes through the hologram 2 as it is hits the non-glare surface 4a of the non-glare plate 4 and is diffused, the non-glare surface 4a becomes dimly bright, which may deteriorate the display quality of the displayed image. In order to cut this 0th order light, a non-glare plate 4
A louver 12 having a light absorbing surface in the horizontal direction is arranged on the back surface of the louver.

Note that when the upper meter hood is removed as in the vehicle display device shown in FIG. 1 or 4, the images of the dial 2, hands 4, etc. on the display portion of the vehicle display device are , it is reflected on the windshield, which is usually arranged obliquely above the vehicle display device, and is reflected as a virtual image, resulting in so-called window reflection, which may obstruct the forward view. This tendency is particularly noticeable at night. In this case, if this louver 12 is arranged, the light directed upward toward the windshield out of the light emitted from the display image 6 formed by the hologram 2 will be absorbed by the dark portion of the louver 12 and will not reach the windshield. Therefore, window reflection of the displayed image can be prevented.

[0023]

[Effects of the Invention] As explained above, according to the present invention,
A non-glare plate is used as the top plate of a vehicle display device, and a hologram is used to form a display image of characters, scales, etc. in a position close to the back of the non-glare plate, so that the display image is blurred. The meter hood for anti-glare can be omitted, and there is no need to place the anti-glare plate as a top plate diagonally, so the overall depth of the device can be shortened and the installation space is reduced, so it can be applied to a wide range of applications. spreads. Furthermore, restrictions on the design of the display device can be reduced. Further, in the case where the louver is arranged adjacent to the back surface of the non-glare plate, the display quality of the displayed image is further improved, and the displayed image is not reflected in the window and obstructs the forward view.

[Brief explanation of drawings]

FIG. 1 is a side view of a vehicle display device according to an embodiment of the present invention.

FIG. 2 is a diagram illustrating how light travels when the distance between a non-glare surface and an image is large.

FIG. 3 is a diagram illustrating how light travels when the distance between the non-glare surface and the image is short.

FIG. 4 is a side view of a vehicle display device according to another embodiment of the present invention.

FIG. 5 is a side view of the vehicle display device for explaining the state of zero-order light passing through the hologram.

FIG. 6 is a side view of a conventional vehicle display device.

[Explanation of symbols]

2 Dial (hologram) 3
Pointer 4 Non-glare plate 5 Light source

Claims (2)

[Claims] [Claim 1] It has a dial made of a hologram on which characters, scales, etc. are recorded, a light source that irradiates the dial with light is provided behind the dial, and an input device is provided in front of the dial. A pointer that is driven in accordance with a signal is arranged, and a non-glare plate is arranged in front of the pointer, and when the light from the light source is irradiated onto the back of the dial, the light diffraction effect of the dial causes the non-glare plate to Letters and text near the back
A display device for a vehicle, characterized in that a display image such as a scale is formed. 2. The display device for a vehicle according to claim 1, further comprising a louver having a horizontal light absorbing surface arranged adjacent to the back surface of the non-glare plate.