Liquid crystal display device

• US 20090115743A1
• Filed: 11/06/2008
• Published: 05/07/2009
• Est. Priority Date: 11/07/2007
• Status: Active Grant

• Current Assignee: Paneltouch Technologies LLC (Touch Display LLC)
• Original Assignee: Hitachi Displays Limited (Japan Display Incorporated)
• Inventors: Oowaki, Yoshio
• Granted Patent: US 8,194,048 B2
• Time in Patent Office: Days
• US Class Current: 345/174
• CPC Class Codes: G06F 3/0412 Digitisers structurally integrated in a display
• CPC Class Codes: G06F 3/04164 Connections between sensors and controllers, e.g. routing lines between electrodes and connection pads
• CPC Class Codes: G06F 3/044 by capacitive means
• CPC Class Codes: G06F 3/0444 using a single conductive element covering the whole sensing surface, e.g. by sensing the electrical current flowing at the corners

Abstract

To realize an increase in an image quality of a liquid crystal display device having a capacitive touch screen, and an increase in a reliability of a contact surface and a connection portion.

A capacitive touch screen 50 and a liquid crystal display panel 30 are connected, by the same flexible wiring substrate 70, on an interior side when the touch screen 50 and the liquid crystal display panel 30 are laid one on top of the other. By so doing, a terminal is protected from an exterior, and an increase in a number of components is suppressed. Also, by installing the capacitive touch screen 50 on a color filter substrate 20 side of the liquid crystal display panel 30, a reduction of a contrast is prevented. Furthermore, a capacitive touch screen substrate 51 side is made a contact surface for an input. By so doing, a conductive layer 52 of the capacitive touch screen 50 is prevented from tearing due to an abrasion caused by a contact.

Claims

1. A liquid crystal display device in which a capacitive touch screen is placed on a liquid crystal display panel in which a liquid crystal layer is sandwiched by a TFT substrate, on which pixel electrodes and thin film transistors are formed in a matrix form, and a color filter substrate on which a color filter is formed, and which has a backlight, wherein

the capacitive touch screen is placed on the color filter substrate, the capacitive touch screen and the TFT substrate are connected by the same flexible wiring substrate, and the backlight is installed at a rear of the TFT substrate, and wherein

a connection portion of the flexible wiring substrate and the TFT substrate is formed on an interior side of the TFT substrate, and a connection portion of the flexible wiring substrate and the capacitive touch screen is formed on an interior side of the capacitive touch screen.

2. The liquid crystal display device according to claim 1, wherein

a substrate of the capacitive touch screen exists on an exterior side.

3. A liquid crystal display device in which a capacitive touch screen is placed on a liquid crystal display panel in which a liquid crystal layer is sandwiched by a TFT substrate, on which pixel electrodes and thin film transistors are formed in a matrix form, and a color filter substrate on which a color filter is formed, and which has a backlight, wherein

the capacitive touch screen is placed on the color filter substrate, the capacitive touch screen and the TFT substrate are connected by the same flexible wiring substrate, and the backlight is installed at a rear of the TFT substrate, wherein

a connection portion of the flexible wiring substrate and the TFT substrate is formed on an interior side of the TFT substrate, and a connection portion of the flexible wiring substrate and the capacitive touch screen is formed on an interior side of the capacitive touch screen, and wherein

there exists a portion in the flexible wiring substrate in which is formed wiring connected only to the capacitive touch screen, and the flexible wiring substrate is folded at the portion in which is formed the wiring connected only to the capacitive touch screen.

4. The liquid crystal display device according to claim 3, wherein

the flexible wiring substrate is folded to a rear surface of the liquid crystal display panel.

5. A liquid crystal display device in which a capacitive touch screen is placed on a liquid crystal display panel in which a liquid crystal layer is sandwiched by a TFT substrate, on which pixel electrodes and thin film transistors are formed in a matrix form, and a color filter substrate on which a color filter is formed, and which has a backlight, wherein

the capacitive touch screen is placed on the color filter substrate, the capacitive touch screen and the TFT substrate are connected by the same flexible wiring substrate, and the backlight is installed at a rear of the TFT substrate, wherein

a connection portion of the flexible wiring substrate and the TFT substrate is formed on an interior side of the TFT substrate, and a connection portion of the flexible wiring substrate and the capacitive touch screen is formed on an interior side of the capacitive touch screen, wherein

there exist portions in the flexible wiring substrate segregated into a portion in which is formed wiring connected only to the capacitive touch screen, and a portion in which is formed wiring connected only to the liquid crystal display panel, and wherein

the flexible wiring substrate is folded at each of the portions segregated into the portion in which is formed the wiring connected only to the capacitive touch screen, and the portion in which is formed the wiring connected only to the liquid crystal display panel.