Display device having multi-touch recognizing function and driving method thereof

• US 9,552,105 B2
• Filed: 05/10/2007
• Issued: 01/24/2017
• Est. Priority Date: 12/13/2006
• Status: Active Grant

• Current Assignee: LG Display Co., Ltd.
• Original Assignee: LG Display Co., Ltd.
• Inventors: Shim, Yeon Shim, Jang, Hyung Uk, Bae, Sang Hyuck
• Primary Examiner(s): Okebato, Sahlu
• Application Number:
  US11/798,125
• Publication Number:
  US 20080143682A1
• Time in Patent Office: 3,547 Days
• Field of Search: 345/175, 178/18.01, 178/18.09
• US Class Current: 1/1
• CPC Class Codes: G06F 3/0428 by sensing at the edges of the touch surface the interruption of optical paths, e.g. an illumination plane, parallel to the touch surface which may be virtual sensing beam interruptions in a planar beam grid of an optical touch-screen G06F3/0421

Abstract

A display device having a multi-touch recognition function includes an integration module having a plurality of cameras integrated at an edge of a display panel; and a processor that detects a touch area using at least first and second images captured by the plurality of cameras, respectively.

Claims

1. A display device having a multi-touch recognition function, comprising:

a display panel for displaying display data representative of a display image;

a plurality of cameras disposed at an edge of the display panel;

a processor that detects a touch area using at least first and second images captured by two cameras of the plurality of cameras, respectively, the touch area being located on a touchable side of the display panel;

a controller synchronized with the processor to control the displaying of a background image on the display panel and the capture of the first and second images by the processor,

at least one non-reflective member in such a spatial relationship with a corresponding each of the plurality of cameras as to prevent an optical interference from an incident light; and

a bracket for receiving the display panel, the plurality of cameras and the at least one non-reflective member,

wherein a first camera of two cameras captures the first image of the display panel and a second camera of two cameras captures the second image of the display panel, respectively, and the processor compares each of the first and second captured images with a displayed image to detect the touch area, and

wherein the controller synchronizes the first and second cameras to capture the first and second images substantially simultaneously,

wherein the at least one non-reflective member includes one of a black layer, an anti-reflector, and first and second polarizing filters which are deposited, the optical absorption axes of which cross each other, and

wherein the at least one non-reflective member is substantially in front of the corresponding each of the plurality of cameras and is lifted upward as much as a designated height from a surface of the display panel, and

wherein the bracket has protrusions at an inner side facing the edges of the display panel, and

wherein the plurality of cameras are disposed on the protrusions and the at least one non-reflective member is overlapped with the edge of the display panel,

wherein the protrusions are parallel to the display panel, and

wherein a bending portion of the bracket covers a top of the at least one non-reflective member.

2. The display device of claim 1, wherein a viewing angle of each of the first and second cameras is in a range of about 80 to about 90 degrees.

3. The display device of claim 1, wherein the height of the at least one non-reflective member above the touchable side of the display panel is proportional to a distance between the touchable side of the display panel and the corresponding one of the cameras.

4. The display device of claim 1, wherein the plurality of cameras further includes third and fourth cameras capturing third and fourth images of the display panel, respectively, and the processor verifies the touch area detected by the first and second cameras with the touch area detected by the third and fourth cameras.

10. The display device according to claim 1, wherein the non-reflective member is located at the edge of the display panel.

11. The display device of claim 1, wherein the plurality of cameras further includes third and fourth cameras capturing third and fourth images of the display panel, respectively, the display device thereby being configured to detect two touch areas, and

when there are two touch points, the processor compares a triangulation result of four pairs of the cameras that are adjacent to each other for each of the two touch points, and if an error value resulting from the comparison of an adjacent camera pair is greater than a threshold, the processor does not take the triangulation result of the adjacent camera pair as either of the touch areas.

5. A display device, comprising:

a display panel for displaying display data representative of a display image;

first and second capture devices assembled with the display panel, each of the first and second capture devices substantially simultaneously capturing first and second captured images of the display panel;

a processor that compares the display data with each of the first and second captured images to detect a touch area on the display panel, the touch area being located on a touchable side of the display panel;

third and fourth capture devices assembled with the display panel, each of the third and fourth capture devices capturing third and fourth captured images of the display panel;

at least one non-reflective member in such a spatial relationship with a corresponding each of the first to the fourth capture devices as to prevent an optical interference from an incident light; and

a bracket for receiving the display panel, the first to fourth capture devices and the at least one non-reflective member,

wherein the processor compares the display data with each of the third and fourth captured images to detect the touch area on the display panel,

wherein the at least one non-reflective member includes one of a black layer, an anti-reflector, and first and second polarizing filters which are deposited, the optical absorption axes of which cross each other, and

wherein the at least one non-reflective member is substantially in front of the corresponding each of the first to the fourth capture devices and is lifted upward as much as a designated height from a surface of the display panel,

wherein the bracket has protrusions at an inner side facing the edges of the display panel, and

wherein the first to fourth capture devices are disposed on the protrusions and the at least one non-reflective member is overlapped with the edge of the display panel,

wherein the protrusions are parallel to the display panel, and

wherein a bending portion of the bracket covers a top of the at least one non-reflective member.

6. The display device of claim 5, wherein the height of the at least one non-reflective member above the touchable side of the display panel is proportional to a distance between the touchable side of the display panel and the corresponding one of the capture devices.

7. The display device of claim 5, wherein a viewing angle of each of the first and second capture devices is small enough to prevent a capture of an unwanted portion of the display panel but large enough to reduce a shade area excluded from the first captured image.

8. The display device of claim 7, wherein the viewing angle of each of the first and second capture devices is in a range of about 80 to about 90 degrees.

9. The display device of claim 5, wherein the processor verifies the touch area detected by the first and second capture devices with the touch area detected by the third and fourth capture devices.

12. The display device of claim 5, wherein the display device includes a multi-touch recognition function, the display device thereby being configured to detect two touch areas, and when there are two touch points, the processor compares a triangulation result of four pairs of the capture devices that are adjacent to each other for each of the two touch points, and if an error value resulting from the comparison of an adjacent pair of capture devices is greater than a threshold, the processor does not take the triangulation result of the adjacent pair of capture devices as either of the touch areas.