JP2003043449A - Liquid crystal display element - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a liquid crystal display element, with which a three dimensional and distinctive-looking information display can be obtained. SOLUTION: The information display screen is constructed as a double layer structure by arranging a passive driven liquid crystal display panel 3 on the front surface side of an active driven liquid crystal display panel 2 with a backlight arranged on the rear side, holding a gap between the panels 3 and 2.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid crystal display device suitable for an on-vehicle display, and more particularly to a liquid crystal display device having a structure in which liquid crystal display panels are arranged in two layers.

[0002]

2. Description of the Related Art Conventionally, liquid crystal display devices have been used as in-vehicle displays such as TN (Twisted Nematic) and ST.
A liquid crystal display device of a passive drive system such as N (Super Twisted Nematic) is used for display of an instrument panel (hereinafter, instrument panel), car audio, etc.
A so-called active drive type liquid crystal display element by an active element such as an in film transistor) is used for display in a navigation system, an information display system and the like.

As described above, in general, the liquid crystal display element as a vehicle-mounted display is
The passive drive type liquid crystal display element and the active drive type liquid crystal display element are used separately.

[0004]

By the way, in recent years, the information density of the vehicle-mounted instrument panel has been increasing. For this reason, liquid crystal display elements of active drive type such as TFT are often used instead of passive drive type elements.

However, even when an active drive type liquid crystal display element is adopted as an instrument panel of an automobile, there is a design problem that the display becomes flat and individual.

[0006] Therefore, an object of the present invention is to provide a liquid crystal display device capable of obtaining information display of a three-dimensional and individual appearance.

[0007]

In order to achieve the above-mentioned object, the liquid crystal display element according to claim 1 of the present invention is characterized in that an active drive type liquid crystal display panel in which a backlight is provided on the back side is provided. A passive drive type liquid crystal display panel is arranged on the front side with a gap, and the information display screen has a two-layer structure.

In the liquid crystal display element having such a structure, the gap is provided between the two liquid crystal display panels,
It is possible to obtain a three-dimensional display, and it is possible to obtain a variety of unique information displays by combining the display utilizing the characteristics of the passive drive system and the display utilizing the characteristics of the active drive system. It will be possible.

The liquid crystal display element according to a second aspect is characterized in that, in the liquid crystal display element according to the first aspect, the gap dimension is 1 to 10 mm.

In the liquid crystal display device having such a structure, since the gap between the two liquid crystal display panels is not too wide, it may be difficult to use the peripheral pixels of the active drive type liquid crystal display panel due to the effect of parallax. In addition, since it is neither too narrow nor too narrow, it is always possible to obtain a stereoscopic effect above a certain level.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION The liquid crystal display element of this embodiment has a structure in which two liquid crystal display panels are laminated in two layers, as shown in FIG.

The liquid crystal display element 1 of the present embodiment has, as an active drive type liquid crystal display panel 2, a transmissive TFT driven liquid crystal display panel 2 provided with a backlight (not shown) on the back side. The structure of the TFT-driven liquid crystal display panel 2 itself is the same as a known one, and the description thereof is omitted.

Further, on the front side of the active drive type liquid crystal display panel 2 of the liquid crystal display element 1 of the present embodiment,
A polarization control type normally white mode display liquid crystal display panel is arranged as the passive drive type liquid crystal display panel 3. This passive drive type liquid crystal display panel 3
For example, a normally white mode liquid crystal display panel such as a TN type or an STN type can be applied. In this embodiment, a normally white mode TN type liquid crystal display panel in which the luminance when an off voltage is applied is higher than the luminance when an on voltage is applied is used. However, the configuration of this TN type liquid crystal display panel itself is known. The same as those described above, and the description thereof is omitted.

The liquid crystal display element 1 of this embodiment is
A TN type passive drive type liquid crystal display panel 3 is arranged on the front side of the active drive type liquid crystal display panel 2 of the TFT having the backlight with a gap.

In this embodiment, the size of the gap 4 between the two liquid crystal display panels 2 and 3 is set to 1 to 10 mm. If the size of the gap 4 between the two liquid crystal display panels 2 and 3 is widened, the stereoscopic effect of the displayed screen is emphasized, but the peripheral pixels of the active drive type liquid crystal display panel 2 are affected by parallax. It becomes difficult to use. On the contrary, if this interval is narrowed, the stereoscopic effect is lost and the display becomes flat. Then, both the liquid crystal display panels 2,
By maintaining 3 with an appropriate gap size and arranging them separately, a stereoscopic effect can be obtained as a visual effect as the information display screen.

Further, the segment type display can have a smooth pattern outer shape, and a fine pattern having a free shape can be used. Therefore, a variety of screen displays can be produced by combining the full dot matrix display displayed on the active drive type liquid crystal display panel 2 and the segment type display displayed on the passive drive type liquid crystal display panel 3. It will be possible.

A more specific example will be described below.

As described above, the liquid crystal display element 1 of this embodiment has a structure in which two liquid crystal display panels 2 and 3 are laminated in two layers. FIG. The screen displayed on the liquid crystal display panel 2 of the active drive system using the TFT installed on the back surface side is shown among the two liquid crystal display panels 2 and 3 constituting the above.

As shown in this figure, as the information to be displayed on the screen of the liquid crystal display panel 2 of the active drive type, information that requires high definition display such as navigation is suitable. In the present embodiment, on the screen of the liquid crystal display panel 2, it is possible to select and display information such as background display, tachometer, trip meter, temperature / air conditioner status in addition to the navigation described above. A mode that can complete the display only by the screen display of the TFT will be prepared.

On the other hand, the liquid crystal display panel 2 can be made to simply function as the backlight of the liquid crystal display panel 3 of the passive drive system. In that case, the brightness and chromaticity can be adjusted, and the visual confirmation of day and night is possible. It is configured so that it is possible to secure the property.

FIG. 3 shows a screen displayed on the normally white mode TN type passive drive type liquid crystal display panel 3 installed on the front side. The liquid crystal display panel 3 includes a segment display type display, and is also configured to display a speedometer, a turn signal, a warning display, etc., in which the number of patterns is limited.

In the present embodiment, the active drive type liquid crystal display panel 2 uses a glass substrate having a thickness of 0.7 mm, and its panel size is slightly larger than that of the passive drive type liquid crystal display panel 3. Form large. Specifically, as the active drive type liquid crystal display panel 2, a diagonally 7-inch horizontally long screen 800 ×
A TN type as a passive drive type liquid crystal display panel 3 in which a full color TFT liquid crystal display panel of 400 dots is arranged, and an effective screen size is 6.5 inches with a 5 mm gap on the front side. Install a positive display liquid crystal display panel. The glass heat of the liquid crystal display panel 3 was 0.7 mm.

As described above, by forming the active drive type liquid crystal display panel 2 arranged on the rear surface side to a slightly larger size, a background screen is displayed on the liquid crystal display panel arranged on the rear surface side. It is possible to prevent the influence of parallax due to the provision of the gap.

The TN normally white mode liquid crystal display panel is preferably driven at 1/4 duty or less from the viewpoint of response speed for vehicle display.

Further, in the present embodiment, the drive system of each liquid crystal display panel 2, 3 is a system separate from the active drive type liquid crystal display panel 2 and the passive drive type liquid crystal display panel 3. With this configuration, for example, in the case of the present embodiment, the display of the passive drive type liquid crystal display panel 3 can function even when the drive system of the active drive type liquid crystal display panel 2 is turned off. Can be

In the liquid crystal display element 1 thus constructed, the gap between the active drive type liquid crystal display panel 2 and the passive drive type liquid crystal display panel 3 is 1 to 1.
By providing 0 mm, a stereoscopic effect can be obtained as a visual effect as the information display screen. Specifically, in the present embodiment, the visual distance is different between the information displayed on the screen of the active drive type liquid crystal display panel 2 and the information displayed on the screen of the passive drive type liquid crystal display panel 3. Therefore, the above-mentioned three-dimensional effect can be obtained. In particular, as shown in FIG. 1, the liquid crystal display panel 2
The screen of the liquid crystal display element 1 is displayed by overlapping the background screen area (hatched area in FIGS. 1 and 2) displayed on the screen of FIG. A navigation map area (see FIG. 1) which is configured to be displayed on the screen as one image or is displayed on the screen of the liquid crystal display panel 2.
2) and a turn signal displayed on the liquid crystal display panel 3 of the passive drive system is displayed so as to be overlapped with a region indicated by a mesh line in FIG. 2 and displayed as one display screen on the display screen of the liquid crystal display element 1. By doing so, it is possible to obtain a display having a stereoscopic effect, which cannot be obtained by the conventional liquid crystal display element 1 including a single-layer liquid crystal display panel. Further, for example, it is possible to improve the visibility by displaying a spot of a desired color on the screen of the liquid crystal display panel 2 as a background of a necessary portion of the monochrome liquid crystal display panel 3.

Further, the segment type display can have a smooth pattern outer shape, and a fine pattern having a free shape can be used. Therefore, by combining the full dot matrix display displayed on the active drive type liquid crystal display panel 2 and the segment type display displayed on the passive drive type liquid crystal display panel 3, various types of liquid crystal display elements 1 can be obtained. It is also possible to produce a screen display.

Furthermore, since the pattern to be displayed on the screen of the liquid crystal display panel 2 can be freely selected, a unique design, background color, tone, etc. can be selected. In some cases, a desired photograph, illustration, or the like can be arranged by linking with a control device such as a personal computer as a display of the active drive type liquid crystal display panel 2.

The present invention is not limited to the above-described embodiment, but various modifications can be made if necessary. For example, in the liquid crystal display element 1 having the above-described configuration, the polarizing plate on the back surface side provided in the liquid crystal display panel 3 of the passive drive system is the polarization plate provided on the front surface side of the display panel 2 of the active drive system. It can also be used as a plate.

[0030]

As described above, according to the present invention,
By utilizing the screen display in two layers of the active drive type liquid crystal display panel and the passive drive type liquid crystal display panel, it is possible to obtain a three-dimensional and individual appearance display. In addition, by making the drive system of the passive drive type liquid crystal display panel independent of the drive system of the active drive type liquid crystal display panel, fail-safe can be achieved.

[Brief description of drawings]

FIG. 1 is a perspective view showing a structure in which two liquid crystal display panels of a liquid crystal display element of the present invention are laminated.

FIG. 2 is a plan view showing a screen displayed on an active drive type liquid crystal display panel installed on the back surface side of the two liquid crystal display panels constituting the liquid crystal display element.

FIG. 3 is a plan view showing a screen displayed on a passive drive type liquid crystal display panel installed on the front surface side of the two liquid crystal display panels constituting the liquid crystal display element.

[Explanation of symbols]

1 Liquid crystal display element 2 (Active drive type) liquid crystal display panel 3 (passive drive type) liquid crystal display panel

Continued front page    F term (reference) 2H088 EA02 EA23 HA08 HA28 JA05                       JA13 MA20                 2H089 HA22 HA31 QA16 RA05 RA10                       TA09 TA18 UA09                 2H091 FA41Z GA13 HA07 HA10                       JA10 LA30 MA03                 3D044 BA21 BA27 BD02

Claims (2)

[Claims] 1. A passive drive type liquid crystal display panel is arranged with a gap on the front side of an active drive type liquid crystal display panel having a backlight on the back side.
A liquid crystal display device having an information display screen having a two-layer structure. 2. The liquid crystal display element according to claim 1, wherein the gap size is formed to be 1 to 10 mm.