Method for adjusting operating frequency of an optical input device according to reference frame changes

• US 7,729,544 B2
• Filed: 06/07/2006
• Issued: 06/01/2010
• Est. Priority Date: 07/01/2005
• Status: Active Grant

• Current Assignee: PixArt Imaging Incorporated
• Original Assignee: PixArt Imaging Incorporated
• Inventors: Lin, Chun-Huang
• Primary Examiner(s): Ahmed; Samir A
• Assistant Examiner(s): HU, FRED H.
• Application Number:
  US11/422,600
• Publication Number:
  US 20070002021A1
• Time in Patent Office: 1,455 Days
• Field of Search: 382/209, 345/166
• US Class Current: 382/209
• CPC Class Codes: G06F 3/0317 in co-operation with a patterned surface, e.g. absolute position or relative movement detection for an optical mouse or pen positioned with respect to a coded surface

Abstract

A method for adjusting an operation frequency of an optical input device is introduced. The method includes capturing and setting a first image as a reference frame of the optical input device; capturing and setting a plurality of frames as a plurality of sample frames of the optical input device; analyzing the plurality of sample frames according to the reference frame; capturing a second image according to a predetermined rule and setting the second image as the reference frame of the optical input device instead of the first image; and adjusting an operation frequency of the optical input device according to a time interval between setting the first image as the reference frame of the optical input device and setting the second image as the reference frame of the optical input device.

Claims

1. A method for adjusting an operation frequency of an optical input device according to a change of a reference frame, the method comprising the following steps:

(a) capturing and setting a first image as a reference frame of the optical input device;

(b) capturing and setting an image as a sample frame of the optical input device;

(c) analyzing the sample frame according to a correlation between the sample frame and the reference frame;

(d) when the correlation between the reference frame and the sample frame is less than a critical value, capturing a second image and setting the second image as the reference frame of the optical input device instead of the first image; and

(e) adjusting number of images captured per second by the optical input device according to a time interval between setting the first image as the reference frame of the optical input device and setting the second image as the reference frame of the optical input device;

wherein the optical input device comprises an image capturing unit;

wherein step (a) and step (b) utilize the image capturing unit to capture images, and step (e) comprises adjusting a capturing frequency of the image capturing unit according to the time interval between setting the first image as the reference frame of the optical input device and setting the second image as the reference frame of the optical input device.

2. The method of claim 1 wherein step (e) comprises decreasing the number of images captured per second by the optical input device when the time interval between setting the first image as the reference frame of the optical input device and setting the second image as the reference frame of the optical input device is longer than a predetermined value.

3. The method of claim 1 wherein step (e) comprises increasing the number of images captured per second by the optical input device when the time interval between setting the first image as the reference frame of the optical input device and setting the second image as the reference frame of the optical input device is shorter than a predetermined value.

4. The method of claim 1 wherein the optical input device comprises a light source for providing light to capture frames;

wherein step (e) comprises adjusting an on/off frequency of the light source according to the time interval between setting the first image as the reference frame of the optical input device and setting the second image as the reference frame of the optical input device.

5. The method of claim 1 wherein the optical input device comprises a radio unit for transmitting signals, wherein step (e) comprises adjusting a signal transmitting frequency of the radio unit according to the time interval between setting the first image as the reference frame of the optical input device and setting the second image as the reference frame of the optical input device.

6. A method for adjusting an operation frequency of an optical input device according to a change of a reference frame, the method comprising the following steps:

(a) capturing and setting a first image as a reference frame of the optical input device;

(b) capturing and setting a plurality of images as a plurality of sample frames of the optical input device;

(c) analyzing the plurality of sample frames according to a correlation between the plurality of sample frames and the reference frame;

(d) when the correlation between the reference frame and the plurality of sample frames is less than a critical value, capturing a second image and setting the second image as the reference frame of the optical input device instead of the first image; and

(e) adjusting number of images captured per second by the optical input device according to number of the sample frames being analyzed during a period of the first image being set as the reference frame of the optical input device;

wherein the optical input device comprises a image capturing unit, wherein step (a) and step (b) utilize the image capturing unit to capturing images, and step (e) comprises adjusting a capturing frequency of the image capturing unit according to the number of the sample frames being analyzed during the period of the first image being set as the reference frame of the optical input device.

7. The method of claim 6 wherein step (e) comprises increasing the number of images captured per second by the optical input device when the number of the sample frames being analyzed during the period of the first image being set as the reference frame of the optical input device is less than a predetermined value.

8. The method of claim 6 wherein step (e) comprises decreasing the number of images captured per second by the optical input device when the number of the sample frames being analyzed during the period of the first image being set as the reference frame of the optical input device is greater than a predetermined value.

9. The method of claim 6 wherein the optical input device comprises a light source for providing light to capture frames, wherein step (e) comprises adjusting an on/off frequency of the light source according to the number of the sample frames being analyzed during the period of the first image being set as the reference frame of the optical input device.

10. The method of claim 6 wherein the optical input device comprises a radio unit for transmitting signals;

wherein step (e) comprises adjusting a signal transmitting frequency of the radio unit according to the number of the sample frames being analyzed during the period of the first image being set as the reference frame of the optical input device.