Screen-input image display device

• US 20090128518A1
• Filed: 11/12/2008
• Published: 05/21/2009
• Est. Priority Date: 11/15/2007
• Status: Active Grant

• Current Assignee: Paneltouch Technologies LLC (Touch Display LLC)
• Original Assignee: Hitachi Displays Limited (Japan Display Incorporated)
• Inventors: Sato, Takeshi, Kinoshita, Masayoshi
• Granted Patent: US 8,077,161 B2
• Time in Patent Office: Days
• US Class Current: 345/174
• CPC Class Codes: G06F 3/0443 using a single layer of sensing electrodes

Abstract

The screen-input image display device has a touch panel for outputting touched locations of a finger or the like in contact with a display panel screen; and a sensing circuit for sensing coordinates of the touched locations based on the output of the touch panel. The touch panel has a transparent conductor film which is single layer on a transparent substrate, the transparent conductor film being patterned into numerous electrode pads arranged in rows and columns of a two-dimensional matrix, and surface areas of the electrode pads vary depending on the location of the touch areas. Coordinates of the touch locations are sensed based on the proportion of charge signals of the touch locations due to differences in surface areas of the electrode pads.

Claims

1. A screen-input image display device comprising:

a touch panel for outputting signals of touched locations of a finger or the like of a user in contact with a display panel screen, the panel being superimposed via touch areas on the screen; and

a sensing circuit for sensing coordinates of the touched locations based on the output of the touch panel, wherein

the touch panel has a transparent conductor film which is single layer on a transparent substrate, the transparent conductor film being patterned into numerous electrode pads arranged in rows and columns of a two-dimensional matrix,

surface areas of the electrode pads vary depending on the location of the touch area, and

coordinates of the touch locations are sensed based on proportion of charge signals of the touch locations due to differences in the surface areas of the electrode pads.

2. The screen-input image display device of claim 1, wherein:

the electrode pads arranged in a row direction and a column direction of the matrix of the touch panel comprise three groups that are repeating every three rows parallel in the row direction, and, viewing the matrix planarly,

surface areas of a first row of electrode pads corresponding to one of the three groups decrease from the left to the right in the row direction and decrease from the bottom to the top in the column direction;

surface areas of a second row of electrode pads corresponding to another one of the three groups are constant going laterally in the column direction and decrease from the top to the bottom of the rows; and

surface areas of a third row of electrode pads corresponding to another one of the three groups increase from the left to the right in the column direction and increase from the top to the bottom in the row direction.

3. The screen-input image display device of claim 1, wherein:

the electrode pads arranged in a row direction and a column direction of the matrix of the touch panel comprise two groups that are repeating every two columns parallel in the row direction, and, viewing the matrix planarly,

surface areas of a first row of electrode pads corresponding to one of the two groups decrease from the left to the right in the row direction and decrease from the bottom to the top in the column direction; and

surface areas of a second row of electrode pads corresponding to the other of the two groups decrease from the left to the right in the row direction and decrease from the top to the bottom in the column direction.

4. The screen-input image display device of claim 1, the sensing circuit comprising:

a comparator in which one input is an output of a current source for providing current to each of groups of the electrode pad, and the other input is a standard voltage;

a timer circuit for counting output magnitude of the comparator as a number of pulses; and

a computing circuit for computing coordinate data of the touch locations based on output of the timer circuit.

5. The screen-input image display device of claim 2, the sensing circuit comprising:

a comparator in which one input is an output of a current source for providing current to each of groups of the electrode pad, and the other input is a standard voltage;

a timer circuit for counting output magnitude of the comparator as a number of pulses; and

a computing circuit for computing coordinate data of the touch locations based on output of the timer circuit.

6. The screen-input image display device of claim 3, the sensing circuit comprising:

a comparator in which one input is an output of a current source for providing current to each of groups of the electrode pad, and the other input is a standard voltage;

a timer circuit for counting output magnitude of the comparator as a number of pulses; and

a computing circuit for computing coordinate data of the touch locations based on output of the timer circuit.

7. The screen-input image display device of claim 1, wherein:

the display panel is a liquid crystal display panel; and

the touch panel has the electrode pads patterned on a transparent substrate superposed on a transparent substrate on a side from which the liquid crystal display panel is viewed.

8. The screen-input image display device of claim 1, wherein:

the display panel is a liquid crystal display panel; and

the touch panel has the electrode pads directly formed into a film and patterned on a transparent substrate on a side from which the liquid crystal display panel is viewed.

9. The screen-input image display device of claim 1, wherein:

the display panel is an organic EL display panel; and

the touch panel has the electrode pads patterned on a transparent substrate superposed on a sealed substrate on a side from which the organic EL display panel is viewed.

10. The screen-input image display device of claim 1, wherein:

the display panel is an organic EL display panel; and

the touch panel has the electrode pads patterned directly on a sealed substrate on a side from which the organic EL display panel is viewed.