Device and related method for converting display screen into touch panel screen

• US 20100328200A1
• Filed: 06/24/2010
• Published: 12/30/2010
• Est. Priority Date: 06/30/2009
• Status: Abandoned Application

• Current Assignee: Avisonic Technology Corporation (Elan Microelectronics Corporation)
• Original Assignee: Avisonic Technology Corporation (Elan Microelectronics Corporation)
• Inventors: Chen, Homer H., Tzeng, Chih-Yang, Chen, Hong-Cheng, Lin, Meng-Chun, Yu, Chi-Chang, Yeh, I-Hau
• Application Number:
  US12/822,187
• Publication Number:
  US 20100328200A1
• Time in Patent Office: Days
• US Class Current: 345/156
• CPC Class Codes: G06F 3/0386 for light pen

Abstract

A device for converting display screen into touch panel screen includes a projection screen; an image projection unit for projecting an image on the projection screen; a light pointer for emitting a light spot signal of a specific wavelength on the projection screen; an image detecting unit, which includes a fisheye lens for receiving the image on the projection screen to generate a fisheye distorted image; and an optical filter for filtering out the optical energy except the light spot signal of the specific wavelength; an image processing unit, coupled to the image detecting unit, for calculating a first position of the light spot on the projection screen according to the fisheye distorted image; and a message transmitting unit, coupled to the image processing unit, for outputting a touch panel signal according to the calculating result of the image processing unit.

Claims

1. A light pointing touch panel display device, which converts a display screen into a touch panel screen, comprising:

a projection screen;

an image projection unit for projecting an image on the projection screen;

a light pointer for emitting a light spot signal of a specific wavelength on the projection screen;

an image detecting unit, comprising;

a fisheye lens for receiving the image on the projection screen to generate a fisheye distorted image; and

an optical filter for filtering out the optical energy except the light spot signal of the specific wavelength;

an image processing unit, coupled to the image detecting unit, for calculating a first position of the light spot on the projection screen according to the fisheye distorted image; and

a message transmitting unit, coupled to the image processing unit, for outputting a touch panel signal according to the calculating result of the image processing unit.

2. The light pointing touch panel display device of claim 1, wherein the image processing unit further comprises:

a receiving unit for receiving the fisheye distorted image;

a recognition unit for determining the first position according to a second position having a fisheye distorted coordinate in the fisheye distorted image;

a calculating unit for calculating the fisheye corrected coordinate of the fisheye corrected image from the fisheye distorted coordinate according to a coordinate transfer function between the fisheye distorted image and the fisheye corrected image, wherein the fisheye corrected coordinate corresponds to the first position on the projection screen; and

an output unit for outputting the fisheye corrected coordinate.

3. The light pointing touch panel display device of claim 2, wherein the coordinate transfer function comprises a fisheye correction coordinate transformation, a keystone correction coordinate transformation.

4. The light pointing touch panel display device of claim 1, wherein the specific wavelength is of an infrared wavelength.

5. The light pointing touch panel display device of claim 1, wherein the maximal azimuthal angle of the fisheye lens between 120 to 160 degrees.

6. The light pointing touch panel display device of claim 2, wherein the touch panel signal comprises the fisheye corrected coordinate.

7. A light pointing touch panel detecting method, which is utilized for converting a display screen into a touch panel screen, comprising:

projecting an image on a projection screen;

emitting a light spot signal of a specific wavelength on the projection screen;

receiving the image on the projection screen to generate a fisheye distorted image;

filtering out optical energy except the light spot signal of the specific wavelength;

calculating a first position of the light spot on the projection screen according to the fisheye distorted image; and

outputting a touch panel signal according to the calculating result of the image processing unit.

8. The light pointing touch panel detecting method of claim 7, wherein calculating the first position of the light spot on the projection screen according to the fisheye distorted image comprises:

receiving the fisheye distorted image;

determining the first position according to a second position having a fisheye distorted coordinate in the fisheye distorted image;

calculating the fisheye corrected coordinate of the fisheye corrected image from the fisheye distorted coordinate according to a coordinate transfer function between the fisheye distorted image and the fisheye corrected image, wherein the fisheye corrected coordinate corresponds to the first position on the projection screen; and

outputting the fisheye corrected coordinate.

9. The light pointing touch panel detecting method of claim 8, wherein the coordinate transfer function comprises a fisheye correction coordinate transformation, a keystone correction coordinate transformation.

10. The light pointing touch panel detecting method of claim 7, wherein the maximal azimuthal angle of the fisheye lens is between 120˜

160 degrees.

11. The light pointing touch panel detecting method of claim 8, wherein the touch panel signal comprises the fisheye corrected coordinate.