Device having touch sensitivity functionality

• US 6,816,537 B2
• Filed: 10/04/2002
• Issued: 11/09/2004
• Est. Priority Date: 10/09/2001
• Status: Expired due to Fees

• Current Assignee: Koninklijke Philips Electronics N.V. (Koninklijke Philips N.V.)
• Original Assignee: Koninklijke Philips Electronics N.V. (Koninklijke Philips N.V.)
• Inventors: Liess, Martin Dieter
• Primary Examiner(s): Wong, Don
• Assistant Examiner(s): AL NAZER, LEITH A
• Application Number:
  US10/264,897
• Publication Number:
  US 20030160155A1
• Time in Patent Office: 767 Days
• Field of Search: 372/109, 345/156, 345/173, 345/175, 250/221
• US Class Current: 372/109
• CPC Class Codes: G06F 3/0423 using sweeping light beams, e.g. using rotating or vibrating mirror

Abstract

The invention relates to a device having touch sensitivity functionality, comprising a surface (2), touch-sensitive means (5) for detecting the presence of a touch input member (6) being in contact with or close to the surface (2) generating a distance sensor signal. Since conventional resistive or capacitive touch-sensitive layers have a limited transparency, they significantly reduce the screen quality. According to the invention, a display device having touch sensitivity functionality is provided without adding a layer to the display, and is characterized in that the touch-sensitive means (5) comprises means (51) for emitting a laser beam (4, 8) in a plane parallel and close to the surface (2), said laser beam being periodically deflected across the entire surface (2), and means (51, 60) for receiving the light reflected or scattered from the touch input member (6) generating said distance sensor signal therefrom.

Claims

1. A device having touch sensitivity functionality, comprising:

a surface,

a touch-sensing component that includes;

a laser emitter that is configured to emit a laser beam,

a deflector that is configured to deflect the laser beam across the surface in a plane parallel to the surface,

a detector that is configured to detect light from the laser beam that is reflected from a touch input member, and

a signal generator that is configured to generate a distance sensor signal that is dependent upon a distance between the detector and the touch input member.

2. The device of claim 1, further including

a signal processor that is configured to determine a position of the touch input member relative to the surface, based on the distance sensor signal.

3. The device of claim 2, wherein

the distance sensor signal is also dependent upon it deflection angle of the laser beam across the surface, and

the signal processor determines the position based on the deflection angle and the distance between the detector and the touch input member.

4. The device of claim 1, wherein

the laser emitter includes a laser diode, and

the detector includes a photodiode.

5. The device of claim 4, wherein

the light front the laser beam that is reflected from the touch input member is scattered back to the laser diode, thereby modulating the emitted laser beam.

6. The device of claim 1, wherein

the touch-sensitive component is mounted at a corner of a frame that encloses the surface.

7. The device of claim 1, wherein

the laser emitter is configured to emit the laser beam in a plane directly above the surface.

8. The device of claim 1, wherein

the detector is further configured to receive light reflected from a frame of the surface, and

the signal generator is further configured to generate the distance sensor signal that is dependent upon a distance between the emitter and the frame as well as the distance from the emitter to the touch input member.

9. The device of claim 1, wherein

a frame of the surface includes laser reflectors positioned to reflect the laser beam to the detector.

10. The device of claim 1, wherein

the touch-sensing component includes:

an oscillator that is configured to reflect the laser beam periodically across the entire surface by periodically changing an orientation of a mirror that deflects the laser beam.

11. The device of claim 1, wherein

the oscillator includes an electronically driven mechanical oscillator.

12. The device of claim 1, wherein

the surface corresponds to a display screen.

13. The device of claim 1, wherein

the surface corresponds to a keyboard, and includes alphanumeric markings.

14. A method of sensing touch of a surface by a touch input member, comprising:

emitting a laser beam

deflecting the laser beam across the surface in a plane parallel to the surface,

detecting light from the laser beam that is reflected from the touch input member, and

generating a distance sensor signal that is dependent upon a distance between the detector and the touch input member.