Touch panels with dynamic zooming and low profile bezels

• US 10,019,112 B2
• Filed: 09/26/2012
• Issued: 07/10/2018
• Est. Priority Date: 10/25/2011
• Status: Expired due to Fees

• Current Assignee: Semiconductor Components Industries LLC (ON Semiconductor Corporation)
• Original Assignee: Semiconductor Components Industries LLC (ON Semiconductor Corporation)
• Inventors: Bakin, Dmitry, Salsman, Kenneth Edward
• Primary Examiner(s): Sitta, Grant
• Application Number:
  US13/627,920
• Publication Number:
  US 20130100082A1
• Time in Patent Office: 2,113 Days
• Field of Search: 345156-175, 245156-175
• CPC Class Codes: G06F 3/042 by opto-electronic means

Abstract

An electronic device may have a touch panel. The touch panel may detect touch events using one or more cameras. The touch panel may include a planar exterior surface, such as a cover glass, that extends over an active region of a display and an inactive peripheral region. The cameras may be located underneath the inactive peripheral region. The cameras may include a light turning element to allow the cameras to detect touch events, without being raised above the exterior surface of the active region of the display (e.g., without having a raised profile). The touch panel may detect touch events using dynamic zooming techniques. As an example, the touch panel may divide the active region into sections, search for touch events in each section, zoom into sections in which touch events are found, and further search the sections in which touch events were found.

Claims

1. A method of using an image sensor in a touch panel to detect at least one touch event, wherein the image sensor comprises an array of image sensor pixels arranged in rows and columns, wherein each of the at least one touch events comprises a touch event selected from the group consisting of:

an object touching a surface of the touch panel in an active region of the touch panel and the object coming within a threshold distance the surface of the touch panel in the active region of the touch panel, and wherein the image sensor is non-overlapping with the active region of the touch panel, the method comprising;

dividing the active region of the touch panel into a first plurality of sections;

receiving light at the image sensor;

detecting, using the image sensor, the touch event in a given one of the sections of the first plurality of sections, based on the received light;

dividing the given one of the sections of the first plurality of sections into a second plurality of sections;

detecting, using the image sensor, the touch event in a given one of the sections of the second plurality of sections, based on the received light;

dividing the given one of the sections of the second plurality of sections into a third plurality of sections; and

detecting, using the image sensor, the touch event in a given one of the sections of the third plurality of sections.

2. The method defined in claim 1 wherein the touch panel includes an array of light emitting elements in the active region of the touch panel and wherein detecting, using the image sensor, the touch event in the given one of the sections of the first plurality of sections comprises:

activating the light emitting elements in the given one of the sections of the first plurality of sections, while the light emitting elements in the other sections of the first plurality of sections are deactivated; and

receiving light with the image sensor that was emitted by the activated light emitting elements in the given one of the sections of the first plurality of sections and that was scattered off of the object.

3. The method defined in claim 1 wherein the touch panel includes an array of light emitting elements in the active region of the touch panel and wherein detecting, using the image sensor, the touch event in the given one of the sections of the first plurality of sections comprises searching for the touch event in each of the sections of the first plurality of sections.

4. The method defined in claim 3 wherein searching for the touch event in each of the sections of the first plurality of sections comprises:

for each of the sections of the first plurality of sections, activating the light emitting elements of that section while deactivating the rest of the light emitting elements in the touch panel; and

for each of the sections of the first plurality of sections, searching, with the image sensor, for light emitted by the activated light emitting elements of that section and scattered off of the object.

5. The method defined in claim 4 wherein detecting, using the image sensor, the touch event in the given one of the sections of the second plurality of sections comprises searching for the touch event in each of the sections of the second plurality of sections.

6. The method defined in claim 5 wherein searching for the touch event in each of the sections of the second plurality of sections comprises:

for each of the sections of the second plurality of sections, activating the light emitting elements of that section while deactivating the rest of the light emitting elements in the touch panel; and

for each of the sections of the second plurality of sections, searching, with the image sensor, for light emitted by the activated light emitting elements of that section and scattered off of the object.

7. The method defined in claim 1 wherein the touch panel comprises an array of visible light emitting elements that are together operable to display at least one image in the active region of the touch panel, wherein the touch panel comprises an array of infrared light emitting elements in the active region of the touch panel, and wherein detecting, using the image sensor, the touch event comprises using the image sensor to detect infrared light emitted by at least some of the infrared light emitting elements.

8. The method defined in claim 1 further comprising:

dividing the given one of the sections of the second plurality of sections into a third plurality of sections; and

detecting, using the image sensor, the touch event in a given one of the sections of the third plurality of sections.

9. A touch panel comprising:

a display module comprising a plurality of pixels arranged in an array, wherein the plurality of pixels comprise infrared light emitting pixels that selectively emit infrared light, wherein the infrared light emitting pixels comprise a plurality of infrared light emitting pixel groups, wherein selected groups of the plurality of infrared light emitting pixel groups are activated while remaining groups of the plurality of infrared light emitting pixel groups are deactivated at a first time, wherein a first set of additional selected groups of the plurality of infrared light emitting pixel groups that are a subset of the selected groups are activated while remaining groups of the plurality of infrared light emitting pixel groups are deactivated at a second time that is after the first time, and wherein a second set of additional selected groups of the plurality of infrared light emitting pixel groups that are a subset of the first set of additional selected groups of the infrared light emitting pixel groups are activated while remaining groups of the plurality of infrared light emitting pixel groups are deactivated at a third time that is after the second time;

at least one camera operable to detect touch events, wherein the at least one camera has an array of image sensor pixels arranged in rows and columns; and

a planar cover member over both the display module and the at least one camera.

10. The touch panel defined in claim 9 wherein the at least one camera is located adjacent to the display module and wherein the at least one camera comprises a light turning element.

11. The touch panel defined in claim 10 wherein the light turning element comprises a light turning film having a lenticular prism array.

12. The touch panel defined in claim 11 further comprising:

wherein at least a portion of the planar cover member comprises light blocking material, wherein the light blocking material obscures inactive peripheral regions of the touch panel and at least a portion of the camera from the view of users of the touch panel.

13. The touch panel defined in claim 9 wherein the display module comprises:

visible light emitting elements operable to display images for users of the touch panel; and

infrared light emitting elements operable to selectively emit infrared light, wherein the camera comprise a camera operable to receive infrared light emitted by the infrared light emitting elements and scattered off one or more objects touching the touch panel.

14. A system, comprising:

a central processing unit;

memory;

input-output circuitry; and

a touch panel, wherein the touch panel comprises;

a display module, comprising;

visible light emitting pixels that display images for users of the touch panel; and

infrared light emitting pixels that selectively emit infrared light, wherein at least a portion of the infrared light emitting pixels are interposed between the visible light emitting pixels, wherein the visible and infrared light emitting elements of the display module are located in an active region of the display module, wherein the active region of the display module is divided into a first plurality of sections, wherein each of the sections of the first plurality of sections is divided into a second plurality of sections, wherein each of the sections of the second plurality of sections is divided into a third plurality of sections; and

circuitry that, at a first time, activates the infrared pixels in a given one of the sections of the first plurality of sections while deactivating the rest of the light emitting elements in the touch panel, at a second time, activates the infrared pixels in a given one of the sections of the second plurality of sections while deactivating the rest of the light emitting elements in the touch panel, and at a third time, activates the infrared pixels in a given one of the sections of the third plurality of sections while deactivating the rest of the light emitting elements in the touch panel; and

a plurality of CMOS cameras together operable to detect when one or more objects are touching the touch panel, wherein each camera is operable to receive infrared light emitted by the infrared light emitting elements and scattered off the one or more objects.

15. The system defined in claim 14 wherein the touch panel further comprises a planar cover member over both the display module and at least one CMOS camera of the plurality of CMOS cameras.

16. The system defined in claim 15 wherein the planar cover member comprises a cover glass member.

17. The system defined in claim 16 wherein the cover glass member comprises a flat surface that extends over both the display module and the at least one CMOS camera.