STYLUS INPUT SYSTEM

• US 20110205244A1
• Filed: 02/25/2010
• Published: 08/25/2011
• Est. Priority Date: 02/25/2010
• Status: Active Grant

• Current Assignee: Hewlett-Packard Development Company, L.P. (HP Inc.)
• Original Assignee: Hewlett-Packard Development Company, L.P. (HP Inc.)
• Inventors: Myers, Bob
• Granted Patent: US 8,436,837 B2
• Time in Patent Office: Days
• US Class Current: 345/634
• CPC Class Codes: G06F 3/0321 by optically sensing the absolute position with respect to a regularly patterned surface forming a passive digitiser, e.g. pen optically detecting position indicative tags printed on a paper sheet constructional details of pen-shaped pointing devices G06F3/03545, G06F3/03542, G06F3/037
• CPC Class Codes: G06F 3/0386 for light pen

Abstract

Embodiments of the present invention enable stylus input on a display device coupled to a processor. According to one embodiment, a stylus control unit detects the presence of a stylus within a display area of a display device and then displays a pair of frames including luminescent images on the display device. Furthermore, luminescent measurement data is transmitted from the stylus to the stylus control unit, and stylus position information is sent to a computer processor based on the received luminescent measurement data.

Claims

1. A method for enabling stylus input on a display device coupled to a computer processor, the method comprising:

detecting, via a stylus control unit, the presence of a stylus within a display area of a display device;

displaying, via a stylus control unit, a pair of image frames on the display device, wherein the pair of image frames comprises of a first image frame including a first luminescent image and a second image frame including a second luminescent image;

receiving, at the stylus control unit, luminescent measurement data transmitted from the stylus; and

transmitting, via a stylus control unit, stylus position information to the processor based on the received luminescent measurement data.

2. The method of claim 1, wherein at least one luminescent image includes a different luminance level at different regions of the display device.

3. The method of claim 2, wherein the stylus includes a sensor configured to measure varying levels of luminance within the at least one luminescent image.

4. The method of claim 3, wherein the sensor is a CMOS active pixel sensor that does not detect color.

5. The method of claim 1, wherein prior to transmitting the stylus position information:

determining, via the stylus control unit, if a predetermined accuracy threshold has been reached.

6. The method of claim 5, wherein if the predetermined accuracy threshold has not been reached:

repeatedly displaying, via the stylus control unit, a subsequent pair of image frames that are smaller than the previously displayed image frames up until the accuracy threshold is reached.

7. The method of claim 6, wherein based on the luminescent data received from the stylus, a y coordinate of the stylus with respect to the display screen is determined by the first luminescent image in the pair of image frames, and an x coordinate of the stylus with respect to the display screen is determined by the second luminescent image in the pair of image frames.

8. The method of claim 7, wherein a central area of each successive pair of image frames is aligned with the determined x coordinate and the determined y coordinate of the stylus associated with the previous pair of image frames.

9. A system comprising:

a display;

a processor coupled to the display;

a stylus control unit coupled to the display and processor; and

a stylus wirelessly connected to the stylus control unit,

wherein the stylus control unit is configured to display a pair of image frames upon detection of the presence of the stylus within a display area of the display; and

wherein the pair of image frames comprises of a first image frame including a first luminescent image and a second image frame including a second luminescent image.

10. The system of claim 9, wherein at least one luminescent image includes different luminance levels at different regions of the display screen.

11. The system of claim 10, wherein the stylus includes a sensor configured to measure varying levels of luminance within the at least one luminescent image.

12. The system of claim 11, wherein the sensor is a CMOS active pixel sensor that does not detect color.

13. The system of claim 9, wherein prior to transmitting the stylus position information, the stylus control unit determines if a predetermined accuracy threshold has been reached.

14. The system of claim 13, wherein if the predetermined accuracy threshold has not been reached, then the stylus control unit repeatedly displays a subsequent pair of image frames that are smaller than the previously displayed image frames up until the accuracy threshold is reached.

15. The system of claim 14, wherein based on the luminescent data received from the stylus, a y coordinate of the stylus with respect to the display screen is determined by the first luminescent image in the pair of image frames, and an x coordinate with respect to the display screen is determined by the second luminescent image in the pair of image frames.

16. The system of claim 15, wherein a central position of each successive pair of image frames is aligned with the determined x coordinate of the stylus and the determined y coordinate of the stylus associated with the previous pair of image frames.

17. A computer readable storage medium containing an executable program that, when executed by a processor, causes the processor to:

detect the presence of a stylus within a display area of a display device;

display a pair of image frames on the display device, wherein the pair of image frames comprises of a first image frame including a first luminescent image and a second image frame including a second luminescent image;

receive luminescent measurement data transmitted from the stylus; and

transmit stylus position information to a computer processor based on the received luminescent measurement data.

18. The computer readable storage medium of claim 17, wherein at least one luminescent image includes a different luminance level at different regions of the display device.

19. The computer readable storage medium of claim 17, further comprising the software causing the processor to:

determine if a predetermined accuracy threshold has been reached, and

repeatedly display a subsequent pair of image frames that are smaller than the previously displayed image frames up until the accuracy threshold is reached.

20. The computer readable storage medium of claim 19, wherein based on the luminescent data received from the stylus, a y coordinate of the stylus with respect to the display screen is determined by the first luminescent image in the pair of image frames, and an x coordinate of the stylus with respect to the display screen is determined by the second luminescent image in the pair of image frames;

and

wherein a central area of each successive pair of image frames is aligned with the determined x coordinate and the determined y coordinate of the stylus associated with the previous pair of image frames.