SYSTEM AND METHOD FOR DIFFERENTIATING BETWEEN POINTERS USED TO CONTACT TOUCH SURFACE

• US 20090160801A1
• Filed: 12/01/2008
• Published: 06/25/2009
• Est. Priority Date: 03/11/2003
• Status: Active Grant

• Current Assignee: Smart Technologies ULC (Hon Hai Precision Industry Co., Ltd.)
• Original Assignee: Smart Technologies ULC (Hon Hai Precision Industry Co., Ltd.)
• Inventors: MORRISON, GERALD D., Holmgren, David E.
• Granted Patent: US 8,456,451 B2
• Time in Patent Office: Days
• US Class Current: 345/173
• CPC Class Codes: G06F 3/03545 Pens or stylus
• 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
• CPC Class Codes: G06F 3/0488 using a touch-screen or digitiser, e.g. input of commands through traced gestures

Abstract

A touch system comprises a touch surface and at least one camera acquiring images of the touch surface. A pointer contact data generator generates pointer position data in response to pointer contact with the touch surface, the pointer position data representing where on the touch surface pointer contact is made. A processor communicates with the at least one camera and the pointer contact data generator. The processor analyzes acquired images to determine the type of pointer used to contact the touch surface, and processes the pointer position data in accordance with the determined type of pointer. In the preferred embodiment the processor distinguishes between pointer tip touch surface contacts, pointer backend touch surface contacts and finger touch surface contacts. A writing function is invoked in response to pointer tip touch surface contacts. An erase function is invoked in response to pointer backend touch surface contacts. Mouse events are generated in response to finger touch surface contacts.

Claims

1. In a touch system including a touch surface on which an image is presented, a processor responsive to contacts made on the touch surface using a pointer and generating image data used to present said image, a method of updating said image data comprising the step of:

assessing pointer position data generated in response to contacts made on the touch surface using the pointer to determine automatically whether the pointer used to make said contacts is a pen tool or finger based on the existence of at least one three-dimensional formation on the pointer; and

updating the image data based on the type of pointer and the pointer activity on the touch surface.

2. The method of claim 1 wherein said pointer attribute is pointer shape, said pointer shape being assessed by examining an image of said pointer.

3. The method of claim 2 wherein during said assessing the pointer shape is examined to determine if said pointer is a pen tool or a finger.

4. The method of claim 3 wherein during updating an editing function is performed when said pointer is pen tool and wherein a mouse event is invoked when said pointer is a finger.

5. The method of claim 4 wherein during the assessing the orientation of the sides of said pointer is examined to determine if said pointer is a pen tool or finger.

6. The method of claim 3 wherein when said pointer is a pen tool, the pointer shape is further assessed to determine whether the pen tool is a writing tool or an erase tool, when said pen tool is a writing tool, the image data being updated so that said image includes writing corresponding to the writing tool activity on said touch surface and when said pen tool is an erase tool, the image data being updated so that writing in said image corresponding to the erase tool activity on said touch surface is removed.

7. The method of claim 3 wherein opposite ends of the pen tool constitute the writing tool and erase tool, said opposite ends having distinct shapes.

8. The method of claim 4 wherein when a writing tool is used, a unique identifier of the writing tool is examined to determine another attribute assigned to the writing tool.

9. The method of claim 3 wherein when said pointer is a finger, the image data is updated in accordance with an invoked mouse event.

10. The method of claim 1 wherein said pointer attribute is pointer position data generated in response to contacts made on the touch surface, the nature of the pointer position data generated determining the type of pointer.

11. The method of claim 1 wherein the generated pointer position data signifies whether the pointer is a pen tool or a finger.