OPTICAL TOUCH SCREEN USING A MIRROR IMAGE FOR DETERMINING THREE-DIMENSIONAL POSITION INFORMATION

• US 20110169782A1
• Filed: 03/23/2011
• Published: 07/14/2011
• Est. Priority Date: 12/10/2002
• Status: Active Grant

• Current Assignee: Neonode, Inc.
• Original Assignee: Neonode, Inc.
• Inventors: Eriksson, Thomas, Shain, Joseph, Goertz, Magnus, Pettersson, Robert, Sparf, Lars, Jansson, Anders, Karlsson, John, Kvist, Niklas
• Granted Patent: US 9,195,344 B2
• Time in Patent Office: Days
• US Class Current: 345/175
• CPC Class Codes: G06F 2203/04101 2.5D-digitiser, i.e. digitiser detecting the X/Y position of the input means, finger or stylus, also when it does not touch, but is proximate to the digitiser's interaction surface and also measures the distance of the input means within a short range in the Z direction, possibly with a separate measurement setup
• CPC Class Codes: G06F 2203/04104 Multi-touch detection in digitiser, i.e. details about the simultaneous detection of a plurality of touching locations, e.g. multiple fingers or pen and finger
• CPC Class Codes: G06F 2203/04808 Several contacts: gestures triggering a specific function, e.g. scrolling, zooming, right-click, when the user establishes several contacts with the surface simultaneously; e.g. using several fingers or a combination of fingers and pen
• CPC Class Codes: G06F 3/04166 Details of scanning methods, e.g. sampling time, grouping of sub areas or time sharing with display driving Synchronisation with the driving of the display or the backlighting unit to avoid interferences generated internally G06F3/04184
• CPC Class Codes: G06F 3/0418 for error correction or compensation, e.g. based on parallax, calibration or alignment
• CPC Class Codes: G06F 3/042 by opto-electronic means
• CPC Class Codes: G06F 3/0421 by interrupting or reflecting a light beam, e.g. optical touch-screen
• CPC Class Codes: G06F 3/0425 using a single imaging device like a video camera for tracking the absolute position of a single or a plurality of objects with respect to an imaged reference surface, e.g. video camera imaging a display or a projection screen, a table or a wall surface, on which a computer generated image is displayed or projected tracking a projected light spot to determine a position on a display surface G06F3/0386
• CPC Class Codes: G06F 3/04845 for image manipulation, e.g. dragging, rotation, expansion or change of colour

Abstract

A touch screen system including a reflective display surface, a camera mounted so as to capture an image of (i) the reflective display surface, (ii) a pointer approaching the reflective display surface, and (iii) a reflection of the pointer on the reflective display surface, and a processor coupled with the camera that determines a three-dimensional location of the pointer relative to the reflective display surface, based on the positions of the pointer and the reflection of the pointer in the image captured by the camera.

Claims

1. A touch screen system comprising:

a reflective display surface;

a camera mounted so as to capture an image of (i) said reflective display surface, (ii) a pointer approaching said reflective display surface, and (iii) a reflection of the pointer on said reflective display surface; and

a processor coupled with said camera that determines a three-dimensional location of the pointer relative to said reflective display surface, based on the positions of the pointer and the reflection of the pointer in the image captured by said camera.

2. The touch screen system of claim 1, wherein said processor determines the location of the pointer relative to said reflective display surface along at least one dimension, based on a mid-point between the pointer and the reflection of the pointer in the image captured by said camera.

3. The touch screen system of claim 1, wherein said processor determines the location of the pointer relative to said reflective display surface along at least one dimension, based on a line connecting the pointer and the reflection of the pointer in the image captured by said camera.

4. The touch screen system of claim 1, wherein said processor determines a distance between the pointer and said reflective display surface, based on a distance between the pointer and the reflection of the pointer in the image captured by said camera.