VIRTUAL PROJECTING INPUT SYSTEM AND INPUT DETECTING METHOD THEREOF

• US 20130162598A1
• Filed: 03/02/2012
• Published: 06/27/2013
• Est. Priority Date: 12/22/2011
• Status: Active Grant

• Current Assignee: Lite-On Technology Corporation
• Original Assignee: Lite-On It Corporation (Lite-On Technology Corporation)
• Inventors: Lin, Wei-Chih
• Granted Patent: US 8,723,800 B2
• Time in Patent Office: Days
• US Class Current: 345/175
• CPC Class Codes: G06F 3/0423 using sweeping light beams, e.g. using rotating or vibrating mirror
• CPC Class Codes: G06F 3/0426 tracking fingers with respect to a virtual keyboard projected or printed on the surface virtual keyboards on touch screens G06F3/04886
• CPC Class Codes: H04N 9/3129 scanning a light beam on the display screen scanning a light beam on a screen in displays other than projection devices G09G3/02; scanning systems in general G02B26/10; projectors using laser light sources in general H04N9/3161
• CPC Class Codes: H04N 9/3173 wherein the projection device is specially adapted for enhanced portability
• CPC Class Codes: H04N 9/3194 including sensor feedback

Abstract

An input detecting method used for a virtual projecting input system includes: emitting an image light beam through a reflecting mirror, and the image light beam forming a projecting point on a projecting plane; enabling the reflecting mirror to swing, so as to enable the image light beam to swing, and the projecting point scanning back and forth on the projecting plane, and generating an input image; detecting a swing frequency of the reflecting mirror, and generating a frequency signal; judging whether an input action occurs, and if yes, generating a detecting signal; and analyzing a phase difference between the frequency signal and the detecting signal, and calculating an input position of the input action according to the phase difference.

Claims

1. An input detecting method, used for input detection of a virtual projecting input system, comprising:

emitting an image light beam through a reflecting mirror, and the image light beam forming a projecting point on a projecting plane;

enabling the reflecting mirror to swing, so as to enable the image light beam to swing, and the projecting point scanning back and forth on the projecting plane to generate an input image;

detecting a swing frequency of the reflecting mirror to generate a frequency signal;

judging whether or not an input action occurs, and if yes, generating a detecting signal; and

analyzing a phase difference between the frequency signal and the detecting signal, and calculating an input position of the input action according to the phase difference.

2. The input detecting method according to claim 1, wherein the frequency signal and the detecting signal are at a same frequency or have a fixed proportional frequency relation.

3. The input detecting method according to claim 1, wherein the step of judging whether the input action occurs comprises:

detecting whether or not a reflected light is received; and

if yes, judging that the input action occurs, and triggering a frequency signal generator to generate the detecting signal.

4. The input detecting method according to claim 1, wherein the step of judging whether or not the input action occurs comprises:

in a first time of complete scanning, when receiving a reflected light beam, judging a first swing angle of the image light beam in a first direction;

in the first time of complete scanning, detecting whether the reflected light beam is received when the image light beam is located at a second swing angle of the first direction, and then setting as a first detecting result;

in a second time of complete scanning, detecting whether the reflected light beam is received when the image light beam is located at the first swing angle of the first direction, and then setting as a second detecting result;

in the second time of complete scanning, detecting whether the reflected light beam is received when the image light beam is located at the second swing angle of the first direction, and then setting as a third detecting result; and

judging whether the keying input action occurs according to the first detecting result, the second detecting result, and the third detecting result.

5. The input detecting method according to claim 4, further comprising:

in the first time of complete scanning, when receiving the reflected light beam, generating a first detecting signal, and

when judging that the keying input action occurs, setting the first detecting signal as the detecting signal.

6. The input detecting method according to claim 4, wherein the complete scanning is that the projecting point completely scans a scope of the input image at a single time.

7. The input detecting method according to claim 4, wherein when the image light beam is located at the first swing angle of the first direction, the projecting point and the virtual projecting input system comprise a first distance, and when the image light beam is located at the second swing angle of the first direction, the projecting point and the virtual projecting input system comprise a second distance, wherein the first distance is smaller than the second distance.

8. The input detecting method according to claim 7, wherein when the first detecting result and the third detecting result are that the reflected light is received, and the second detecting result is that the reflected light is not received, occurring of the keying input action is judged.

9. An input detecting method, used for input detection of a virtual projecting input system, comprising:

emitting an image light beam through a reflecting mirror, and the image light beam forming a projecting point on a projecting plane;

enabling the reflecting mirror to swing, so as to enable the image light beam to swing, and the projecting point scanning back and forth on the projecting plane, and generating an input image;

in a first time of complete scanning, when receiving a reflected light beam, judging a first swing angle of the image light beam in a first direction;

in the first time of complete scanning, detecting whether the reflected light beam is received when the image light beam is located at a second swing angle of the first direction, and then setting as a first detecting result;

in a second time of complete scanning, detecting whether the reflected light beam is received when the image light beam is located at the first swing angle of the first direction, and then setting as a second detecting result;

in the second time of complete scanning, detecting whether the reflected light beam is received when the image light beam is located at the second swing angle of the first direction, and then setting as a third detecting result; and

judging whether a keying input action occurs according to the first detecting result, the second detecting result, and the third detecting result.

10. The input detecting method according to claim 9, further comprising:

detecting a swing frequency of the reflecting mirror, and generating a frequency signal;

if judging that the keying input action occurs, generating a detecting signal; and

analyzing a phase difference between the frequency signal and the detecting signal, and calculating an input position of the input action according to the phase difference.

11. The input detecting method according to claim 10, wherein the frequency signal and the detecting signal comprise the same frequency or form a fixed frequency proportion relation.

12. The input detecting method according to claim 10, wherein in the first time of complete scanning, when receiving the reflected light beam, generating a first detecting signal, and when judging that the keying input action occurs, setting the first detecting signal as the detecting signal.

13. The input detecting method according to claim 9, wherein the complete scanning is that the projecting point completely scans a scope of the input image at a single time.

14. The input detecting method according to claim 9, wherein when the image light beam is located at the first swing angle of the first direction, the projecting point and the virtual projecting input system comprise a first distance, and when the image light beam is located at the second swing angle of the first direction, the projecting point and the virtual projecting input system comprise a second distance, wherein the first distance is smaller than the second distance.

15. The input detecting method according to claim 14, wherein when the first detecting result and the third detecting result are that the reflected light is received, and the second detecting result is that the reflected light is not received, occurring of the keying input action is judged.

16. A virtual projecting input system, comprising:

a projecting device, comprising a reflecting mirror module, used to emit and swing an image light beam, so that the image light beam forms a projecting point on a projecting plane, and the projecting point scans back and forth on the projecting plane, so as to generate an input image, wherein the reflecting mirror module comprises a frequency signal corresponding to a swing frequency of the reflecting mirror module;

a light detector, used to detect a reflected light of the image light beam to a touch object, and generate a triggering signal;

a frequency signal generating unit, used to generate a detecting signal according to the triggering signal; and

a phase analyzer, used to analyze a phase difference between the detecting signal and the frequency signal, and calculate an input position of the touch object according to the phase difference.

17. The virtual projecting input system according to claim 16, wherein the frequency signal and the detecting signal comprise the same frequency or form a fixed frequency proportion relation.

18. The virtual projecting input system according to claim 16, further comprising a frequency detecting device, used to detect the swing frequency of the reflecting mirror module.

19. The virtual projecting input system according to claim 18, wherein the frequency detecting device is a capacitance electrode, and form a capacitor with the reflecting mirror module, for detecting the swing frequency of the reflecting mirror module.

20. The virtual projecting input system according to claim 18, wherein the frequency detecting device is an optical detector, used to detect the swing frequency of the reflecting mirror module.