JPH05313144A - Display module - Google Patents

Abstract

PURPOSE:To constitute the module wherein a liquid crystal cell and coordinate input are effectively and electromagnetically separated. CONSTITUTION:The liquid crystal cell 1 is stored in a metallic frame body 5 which has a display window having a step part 51 at its periphery. A position sensor substrate 2 which is used for a position sensor means is arranged above the frame body 5, a conductive thin film 21 is formed on the substrate top surface of the liquid crystal cell 1 or the reverse surface of the position sensor substrate 2, and the substrate which has the conductive thin film 21 is fixed so as to electrically contact the frame body 5. Consequently, the conductive thin film 21 which is connected to a specific potential can be arranged between the position sensor substrate 2 and liquid crystal cell 1.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a display module with a so-called coordinate input device.

[0002]

2. Description of the Related Art Conventionally, JP-A-62-100827, JP-A-63-53595, and JP-A-3-156.
As shown in Japanese Patent Publication No. 489, a display module has been proposed and partially implemented, in which a liquid crystal cell and a position sensor means are stacked and coordinate input (including key input) is performed while viewing the display. In this case, a touch panel having a matrix contact or a position sensor means using electrostatic capacitance has a position sensor substrate laminated on the upper side of a liquid crystal cell, and a proximity sensor or an electromagnetic transfer type position sensor means is a liquid crystal cell. A position sensor substrate is arranged above or below the device, and when the display surface is pointed by an indicator or the like, the coordinates thereof are detected.

[0003]

In any of the display modules having such a coordinate input, the coordinate detection becomes unstable when the liquid crystal is driven or due to electromagnetic waves emitted from the outside. Due to mutual interference with the liquid crystal display, inconvenience such as deterioration of display quality occurs. In addition, when a large number of substrates are stacked in such a display module, not only the contour of the display is blurred and the contrast is lowered, but also the modules are thickened to support each substrate, which is inconvenient.

[0004]

The present invention has been made in consideration of the above points, and a specific potential is provided between the position sensor substrate used for the position sensor means arranged above the liquid crystal cell and the liquid crystal cell. And a conductive thin film connected to. Further, according to the present invention, the liquid crystal cell is housed, the liquid crystal cell is housed in a metal frame body having a display window having a stepped portion in the periphery, and the position sensor substrate used for the position sensor means is arranged above the frame body. Then, the substrate having the conductive thin film is fixed so as to be in electrical contact with the frame.

[0005]

By arranging the conductive thin film between the liquid crystal cell and the sensor substrate, it is possible to electromagnetically separate the two without affecting display quality. Further, by fixing the substrate having the conductive thin film to the liquid crystal cell housing frame, the substrate can be effectively fixed and the electromagnetic shield can be performed without increasing the thickness.

[0006]

1 is a side sectional view of a display module according to an embodiment of the present invention. In the figure, reference numeral 1 denotes an electrolytic effect type liquid crystal cell, for example, a so-called super twist nematic liquid crystal display in which liquid crystal molecules are twisted by 220 degrees, and polarizing plates are attached to both surfaces of the substrate so as to sandwich the liquid crystal layer. .. Reference numeral 2 denotes a position sensor substrate used for position sensor means arranged above the liquid crystal cell 1, which is composed of a touch panel having a matrix contact, a capacitance detection substrate utilizing electrostatic capacitance, an electromagnetic transfer action type coil integrated substrate, and the like. The position sensor substrate is composed of a single substrate or a laminated substrate, but both use a plate glass or a hard transparent plate using an acrylic resin plate having a sufficient thickness, and more preferably the liquid crystal cell 1 and the position sensor substrate. A certain space is secured between the two so that optical interference fringes and the like do not appear on the display.
The conductive thin film 21 is provided on the back surface of the single substrate when it is made of a single substrate, and at least the back surface of the sensor surface and the exposed surface around the sensor when it is made of a laminated substrate.

Reference numeral 3 denotes a light guide plate laminated below the liquid crystal cell 1, which is made of acrylic resin or the like, has a light source 4 arranged on one side, and a white paint is applied to the back surface or white glossy paper if necessary. A reflection sheet made of aluminum foil or the like is attached, and a light diffusion sheet is attached to the surface. The liquid crystal cell 1 and the light guide plate 3 are housed in a metal frame 5 having a display window 52 having a step portion 51 on the periphery.

The position sensor substrate 2 is fitted in the step portion 51 of the frame body 5, and at that time, a conductive thin film is formed so that the thin film conductive film 21 of the position sensor substrate 2 is in electrical contact with the frame body 5. By fixing the substrate to be held and further fixing the frame body 5 to the ground potential, a conductive thin film regulated to a specific potential is arranged between the position sensor substrate and the liquid crystal cell, and both are electromagnetically coupled. Is separated into

In such a structure, the position sensor substrate 2 is laminated on the liquid crystal cell 1 via a spacer when the metal frame 5 is not used, and is connected to a specific potential by the spacer or the support of the position sensor substrate 2. Just do it. However, in such a configuration, a member for fixing the position sensor substrate 2 and the liquid crystal cell 1 is separately required, and the module becomes thick. Therefore, as described above, the gap between the liquid crystal cell 1 and the position sensor substrate 2 is kept constant by utilizing the step of the metal frame 5, and the module is thinned to securely hold and fix the position sensor substrate 2. be able to.

Further, although the conductive thin film 21 is provided on the back surface of the position sensor substrate 2 in the above description, the invention is not limited to this, and it is sufficient if it is located between the liquid crystal cell and the sensor surface. For example, it may be provided on the surface of the upper substrate of the liquid crystal cell 1, or when the position sensor substrate 2 is a thin substrate or sheet, it may be provided on a transparent hard plate for lining it. Even with such a configuration, since the conductive thin film is thin, it does not bleed the display, but the substrate having the conductive thin film is fixed with a metal frame body, and the conductive thin film is fixed through the frame body. Connecting to a specific potential is preferable because the structure is simple and robust.

[0011]

As described above, according to the present invention, since the conductive thin film is arranged between the liquid crystal cell and the position sensor substrate as described above, there is little blurring of the display position due to bleeding of the display contour and parallax, and the deterioration of the contrast is small. It is possible to electromagnetically separate the two without affecting the quality.

By fixing a substrate having a conductive thin film (a position sensor substrate or a backing hard substrate in the above example) to the liquid crystal cell housing frame, the substrate can be effectively fixed and the electromagnetic shield can be performed without increasing the thickness.

[Brief description of drawings]

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

[Explanation of symbols]

 1 Liquid crystal cell 2 Position sensor substrate 21 Conductive thin film 3 Light guide plate 4 Light source 5 Frame 51 Stepped portion

Claims (2)

[Claims] 1. A display module with a coordinate input device having a liquid crystal cell and a position sensor substrate used for position sensor means arranged above the liquid crystal cell, wherein a specific potential is provided between the position sensor substrate and the liquid crystal cell. And a conductive thin film connected to the display module. 2. A position sensor used for a liquid crystal cell, a metal frame housing the liquid crystal cell and having a display window having a stepped portion in the periphery, and position sensor means arranged above the frame. A display module with a coordinate input device having a substrate, wherein the substrate having a conductive thin film is fixed so as to be in electrical contact with the frame body.