JPH0213214Y2 - - Google Patents

Description

[Detailed Description of the Invention] This invention relates to, for example, a display instrument panel mounted on an automobile.

A conventional device of this type is shown in FIG.

In the figure, 1 is the steering wheel, 2 is the driver, 3 is the roof, 4 is the windshield, 5 is the bonnet, 6 is the hood, 7 is the eye spot, 8 is the eye spot area, 9 is the eye line, 10 is the instrument panel, 11 is a front cover.

Today, pointer (mechanical) type meters as shown in Figure 1 are mainly used as instrument panels for automobiles. The display surface of a pointer-type meter defined by the rotating surface of the pointer is:
As shown in the figure, it is mounted in an area visible from the eye spot 7 through the inside of the steering wheel loop so as to be almost directly facing the driver's 2 face.

On the other hand, there have been many attempts to apply liquid crystal display technology to automobile instrument displays in place of pointer-type meters.

Even when a proposed LCD instrument panel is installed in a car, the display surface, which is defined by the element board surface, is mounted at an angle that almost directly faces the driver's face. The display surface was usually located at the back of the hood 6.

By the way, mechanical instrument panels generally have scales and symbols drawn in bright colors such as white on a background colored in a dark color, typically black. The needles were rotating in bright colors such as yellow or white, and the dark color mentioned above was coated with a so-called black non-reflective coating, so even if the driver faced the display screen directly, it would be difficult to see. In particular, there were no faces or hands visible.
However, in automobile instrument panels that use display elements that are partially made of glass, such as liquid crystal display elements, plasma display elements, and fluorescent display tubes, Since there is considerable surface reflection on the glass surface and the surface of the display surface is flat, the driver's own face and hands, the steering wheel, or the ceiling near the driver's head may be reflected on the instrument display surface. Something happened. For this reason, attempts have been made to make the front panel so-called non-glare in order to prevent this, but although this makes the projected image blurry, the result is that the dark areas of the background become brighter on average. It was bringing. Others have attempted to reduce surface reflection by lowering the surface reflectance of glass etc. by using multiple thin film coatings, etc., but in devices using liquid crystal display elements, reflections on the surface of polarizing plates, etc. However, a sufficient surface antireflection effect has not yet been obtained. Another method is to apply this method to a liquid crystal display element (guest host type LCD) that does not require a front polarizing plate, but this type of liquid crystal display element is sufficient in itself. It has not yet reached a level of reliability. In this way, conventional displays that attempted to apply new display elements such as liquid crystal display elements to automobile instrument panels were constructed with display surface angles that were almost the same as mechanical meters. Images of your face, hands, steering wheel ceiling, etc. may be overlaid on the instrument display, which is the intended purpose, due to surface reflections, or you may not be able to obtain a display with a high contrast ratio due to poor signal-to-noise ratio, or the instrument display may be difficult to read. This increases the number of reading errors, which is undesirable for drivers and may even lead to accidents, so it has not yet been put into practical use.

This invention was made to eliminate the drawbacks of the conventional ones as described above, and it is by tilting the LCD display surface by an angle determined by the relationship with the length of the hood that protrudes from the side and front of the display surface. Therefore, in other words, the object is to provide a display instrument panel that has the shortest hood length when tilted at a certain angle and eliminates the adverse effect on visibility due to surface reflection on the display surface.

An embodiment of this invention will be described below.
In FIG. 2, numerals 1 to 9 are the same as those of the conventional device, so the explanation will be omitted. 10 is a liquid crystal display instrument panel, and 12 is a perpendicular line drawn to the lower end of the display surface of the liquid crystal display instrument panel 10. Note that the display surface of the liquid crystal display instrument panel 10 is tilted only from a line perpendicular to the eyeline 9, and this angle is such that the amount of light emitted from the tip of the hood 6 that is reflected at the lower end of the display surface for necessary display is It is set so that it passes over the eye spot area 8. The optical system of the liquid crystal display instrument panel 10 is composed of at least a surface light source for illumination, a liquid crystal display element, and a front housing panel (also called an escutcheon panel) that are arranged in parallel at least, and the surface of the front housing panel and the liquid crystal display element are parallel to each other. At least one surface (which may be the surface of a polarizing plate) is sometimes treated with a non-glare treatment.

In such a configuration, the display light emitted from the display surface of the instrument panel reaches the driver's eyes as before, but
The driver's own face, hands, steering wheel, or ceiling are not reflected on the display surface. At least most of what is reflected there is the inner wall surface of the hood 6, and since the hood 6 has a dark hue and is treated with a non-light-selective treatment agent, the light intensity level of the visible image is extremely small. A state almost equivalent to seeing nothing reflected has been achieved.

That is, when looking at the necessary display surface of the liquid crystal display instrument panel 10 from the eye spot area 8, which is defined as the area where 95% of the driver's 2 eyes are located, the hood 6
It is when you look at the bottom edge of the display screen from the eye spot area 8 that you can almost see anything other than the inner wall surface.
Even in this case, the instrument panel is set so that it does not reflect anything other than the inner wall of the hood, so whenever you view the display surface from the eye spot area 8, you will always see the original display, resulting in a good display. The above S/N ratio was obtained.

Note that if the angle is made too large, the contrast ratio will rapidly decrease due to the viewing angle characteristics of the liquid crystal display element, which in turn will reduce visibility, so in the end there is an optimal range, and experiments have shown that the angle is between 15° and 60°. It was confirmed that this range falls within this range.

In addition, it was similarly confirmed that in order to reduce the volume occupied by the entire instrument panel, it is better to divide the display surface into multiple stages and attach a short hood to each stage.

Although the above-mentioned embodiment was related to an automobile instrument panel, the present invention is applicable to an instrument panel provided in the driver's seat of an airplane, a ship, a train, etc., where the driver's seat is almost constant. The same effects as those of the above embodiments can be obtained.

As described above, according to the present invention, the display surface of the display instrument panel is configured to be mounted at a predetermined angle determined from the protruding length of the hood and the relationship with the eyeline, so that the display contrast due to surface reflection is Visibility was greatly improved, and for example, liquid crystal display devices were put into practical use, and their economic effects were greatly improved. Extremely large.

[Brief explanation of drawings]

FIG. 1 is a sectional view showing a conventional device, and FIG. 2 is a sectional view showing an embodiment of the present invention. In the figure, 1 is the steering wheel, 2 is the driver,
3 is the roof, 4 is the windshield, 5 is the bonnet,
6 is a hood, 7 is an eye spot, 8 is an eye spot area, 9 is an eye line, 10 is a liquid crystal display instrument panel, and 12 is a normal line to the lower end of the display surface. Note that the same reference numerals in each figure indicate the same or corresponding parts.

Claims (1)

[Scope of Claim for Utility Model Registration] (1) A vehicle comprising a flat display surface attached to the front of the driving position and displaying information to the driver, and a hood protruding above the display surface. , the wall surface of the hood is arranged at a position that intersects a straight line symmetrical to a straight line connecting the driver's eye point area and the display surface with respect to a plane perpendicular to the display surface, and the size of the wall surface of the hood is A display instrument panel characterized in that, when the display surface is viewed from the eye point area, almost only the entire wall surface of the hood is reflected on the display surface. (2) A claim for utility model registration characterized in that the display surface is arranged at an angle of 15° or more and 60° or less with respect to a line perpendicular to the eyeline connecting the display surface and the eyepoint area. The display instrument panel described in paragraph 1.