Navigation trace calibrating method and related optical navigation device

• US 10,007,359 B2
• Filed: 01/27/2016
• Issued: 06/26/2018
• Est. Priority Date: 10/07/2015
• Status: Active Grant

• Current Assignee: PixArt Imaging Incorporated
• Original Assignee: PixArt Imaging Incorporated
• Inventors: Chung, Ching-Lin, Ke, Chia-Fu
• Primary Examiner(s): BALAOING, ARIEL A
• Application Number:
  US15/007,218
• Publication Number:
  US 20170102790A1
• Time in Patent Office: 881 Days
• CPC Class Codes: G06F 3/03542 Light pens for emitting or receiving light
• CPC Class Codes: G06F 3/03545 Pens or stylus
• CPC Class Codes: G06F 3/0383 Signal control means within the pointing device

Abstract

A navigation trace calibrating method and a related optical navigation device are utilized to transform a first trace line generated by the optical navigation device into a second trace line suitable for user operation. The navigation trace calibrating method includes establishing a reference coordinate system, reading and analyzing the first trace line, calculating a first offset of the first trace line relative to the reference coordinate system, defining an offset between the first trace line and the second trace line as calibration weight to acquire a second offset of the second trace line relative to the reference coordinate system, and calculating a value of the calibration weight according to the second offset and a length of the first trace line.

Claims

1. A navigation trace calibrating method of transforming a first trace line generated by an optical navigation device into a second trace line suitable for user operation, the navigation trace calibrating method comprising:

establishing a reference coordinate system;

reading and analyzing the first trace line;

calculating a first offset of the first trace line relative to the reference coordinate system;

defining an offset between the first trace line and the second trace line as calibration weight to acquire a second offset of the second trace line relative to the reference coordinate system; and

calculating a value of the calibration weight according to the second offset and a length of the first trace line.

2. The navigation trace calibrating method of claim 1, further comprising:

transforming the first trace line into the second trace line by the calibration weight; and

defining the second trace line as a navigation trace of the optical navigation device.

3. The navigation trace calibrating method of claim 1, wherein the optical navigation device utilizes a navigation chip to generate the first trace line, the navigation trace calibrating method further comprises:

rotating the navigation chip according to the calibration weight; and

setting a trace line generated by the rotated navigation chip as a navigation trace of the optical navigation device.

4. The navigation trace calibrating method of claim 1, further comprising:

utilizing an angle sensor to detect a self-rotary angle of the optical navigation device; and

adjusting the calibration weight dynamically according to variation of the self-rotary angle.

5. The navigation trace calibrating method of claim 4, wherein a step of adjusting the calibration weight dynamically according to the variation of the self-rotary angle is executed by utilizing a linear trace prediction theory to adjust the calibration weight.

6. The navigation trace calibrating method of claim 1, wherein a step of reading and analyzing the first trace line is executed by establishing a calibration circle on the reference coordinate system, and a radius of the calibration circle is equal to the first trace line.

7. The navigation trace calibrating method of claim 1, wherein a step of calculating the first offset of the first trace line relative to the reference coordinate system is executed by acquiring a projection length of the first trace line upon the reference coordinate system, and then calculating the first offset by the projection length and the length of the first trace line.

8. The navigation trace calibrating method of claim 1, wherein a step of calculating the value of the calibration weight according to the second offset and the length of the first trace line comprises:

defining a projection length of the second trace line upon the reference coordinate system by the second offset; and

utilizing the foresaid projection lengths, the lengths of the first trace line and the second trace line, and triangle side length formula to calculate the value of the calibration weight.

9. The navigation trace calibrating method of claim 1, wherein difference between the first offset and the calibration weight is equal to the second offset.

10. An optical navigation device with navigation trace calibrating function, capable of transforming a first trace line generated by the optical navigation device into a second trace line suitable for user operation, the optical navigation device comprising:

a navigation chip adapted to generate the first trace line; and

a control unit electrically connected to the navigation chip and adapted to acquire information of the first trace line, the control unit utilizing the navigation chip to establish a reference coordinate system, analyzing the first trace line and calculating a first offset of the first trace line relative to the reference coordinate system, defining calibration weight between the first trace line and the second trace line to acquire a second offset of the second trace line relative to the reference coordinate system, and calculating a value of the calibration weight according to the second offset and a length of the first trace line.

11. The optical navigation device of claim 10, wherein the control unit is integrated with the navigation chip, or is a control chip independent of the navigation chip, or is an operating processor of a computer system independent of the navigation chip.

12. The optical navigation device of claim 10, wherein the control unit transforms the first trace line into the second trace line by the calibration weight, and the second trace line is defined as a navigation trace of the optical navigation device.

13. The optical navigation device of claim 10, further comprising:

a rotary mechanism electrically connected to the control unit and adapted to hold the navigation chip, the control unit utilizing the rotary mechanism to rotate the navigation chip via the calibration weight, and setting a trace line generated by the rotated navigation chip as a navigation trace of the optical navigation device.

14. The optical navigation device of claim 13, further comprising:

an angle sensor electrically connected to the control unit, the control unit utilizing the angle sensor to detect a self-rotary angle of the optical navigation device, and dynamically adjusting the calibration weight by the rotary mechanism according to variation of the self-rotary angle.

15. The optical navigation device of claim 14, wherein the control unit utilizes a linear trace prediction theory to adjust the calibration weight.

16. The optical navigation device of claim 10, wherein the control unit analyzes the first trace line to establish a calibration circle on the reference coordinate system, and a radius of the calibration circle is equal to the first trace line.

17. The optical navigation device of claim 10, wherein the control unit acquires a projection length of the first trace line upon the reference coordinate system, and then calculates the first offset by the projection length and the length of the first trace line.

18. The optical navigation device of claim 10, wherein the control unit defines a projection length of the second trace line upon the reference coordinate system by the second offset, and utilizes the foresaid projection lengths, the lengths of the first trace line and the second trace line, and triangle side length formula to calculate the value of the calibration weight.

19. The optical navigation device of claim 10, wherein difference between the first offset and the calibration weight is equal to the second offset.