Optical finger mouse, electronic device and physiological characteristics detection device

• US 9,301,694 B2
• Filed: 09/13/2012
• Issued: 04/05/2016
• Est. Priority Date: 09/21/2011
• Status: Active Grant

• Current Assignee: PixArt Imaging Incorporated
• Original Assignee: PixArt Imaging Incorporated
• Inventors: Gu, Ren Hau, Kao, Ming Tsan, Huang, Sen Huang
• Primary Examiner(s): WINAKUR, ERIC FRANK
• Application Number:
  US13/614,999
• Publication Number:
  US 20130072771A1
• Time in Patent Office: 1,300 Days
• US Class Current: 1/1
• CPC Class Codes: A61B 5/0205 Simultaneously evaluating both cardiovascular conditions and different types of body conditions, e.g. heart and respiratory condition
• CPC Class Codes: A61B 5/02433 for infrared radiation
• CPC Class Codes: A61B 5/14551 for measuring blood gases
• CPC Class Codes: A61B 5/6826 Finger
• CPC Class Codes: A61B 5/6897 Computer input devices, e.g. mice or keyboards
• CPC Class Codes: A61B 5/7207 of noise induced by motion artifacts
• CPC Class Codes: A61B 5/7214 using signal cancellation, e.g. based on input of two identical physiological sensors spaced apart, or based on two signals derived from the same sensor, for different optical wavelengths
• CPC Class Codes: G06F 3/0304 Detection arrangements using opto-electronic means constructional details of pointing devices not related to the detection arrangement using opto-electronic means G06F3/033; optical digitisers G06F3/042
• CPC Class Codes: G06F 3/0354 with detection of 2D relative movements between the device, or an operating part thereof, and a plane or surface, e.g. 2D mice, trackballs, pens or pucks
• CPC Class Codes: G06F 3/0421 by interrupting or reflecting a light beam, e.g. optical touch-screen
• CPC Class Codes: G06F 3/0425 using a single imaging device like a video camera for tracking the absolute position of a single or a plurality of objects with respect to an imaged reference surface, e.g. video camera imaging a display or a projection screen, a table or a wall surface, on which a computer generated image is displayed or projected tracking a projected light spot to determine a position on a display surface G06F3/0386

Abstract

There is provided an optical finger mouse including two light sources, an image sensor and a processing unit. The two light sources emit light of different wavelengths to illuminate a finger surface. The image sensor receives reflected light from the finger surface to generate a plurality of image frames. The processing unit detects a displacement and a contact status of the finger surface and a physiological characteristic of a user according to the plurality of image frames. There is further provided an electronic device and a physiological characteristic detection device.

Claims

1. An optical finger mouse configured to detect a displacement of a finger of a user and a physiological characteristic of the user, the optical finger mouse comprising:

a first light source configured to emit light of a first wavelength to the finger;

a second light source configured to emit light of a second wavelength to the finger;

a light control unit configured to control an on-state and an off-state of the first light source and the second light source;

an image sensor configured to capture reflected light from the finger with a sampling frequency to generate a plurality of first image frames corresponding to the on-state of the first light source and a plurality of second image frames corresponding to the on-state of the second light source; and

a processing unit configured to calculate both of the displacement of the finger for controlling a cursor and the physiological characteristic according to the first image frames and the second image frames captured by the image sensor,

wherein in calculating the physiological characteristic, the processing unit is configured to

divide each of the first image frames into at least two parts and calculate an average brightness of each part,

analyze the average brightness of the each part of the first image frames to obtain a first intensity variation,

divide each of the second image frames into at least two parts and calculate an average brightness of each part,

analyze the average brightness of the each part of the second image frames to obtain a second intensity variation, and

calculate the physiological characteristic according to the first intensity variation and the second intensity variation.

2. The optical finger mouse as claimed in claim 1, wherein the physiological characteristic comprises a blood oxygenation and a heart rate.

3. The optical finger mouse as claimed in claim 1, wherein the processing unit is further configured to calculate a heart rate according to a comparison of at least one pulse threshold with at least one of the first intensity variation and the second intensity variation.

4. The optical finger mouse as claimed in claim 1, wherein the processing unit is further configured to calculate a sum of M image frames for denoising, and normalize the sum or an average of the M image frames with a sampling parameter, wherein M is a positive integer.

5. The optical finger mouse as claimed in claim 1, wherein

the light control unit is configured to enable the off-state of the first light source and the second light source in predetermined time intervals such that the image sensor captures a plurality of bright first image frames, a plurality of bright second image frames and a plurality of dark image frames;

and

the processing unit is configured to calculate the displacement and the physiological characteristic according to a difference between the bright first image frames and the dark image frames and according to a difference between the bright second image frames and the dark image frames.

6. The optical finger mouse as claimed in claim 1, wherein the optical finger mouse is configured to enter a sleep mode after idling for a predetermined time period.

7. The optical finger mouse as claimed in claim 1, wherein the processing unit is configured to not calculate or is configured to ignore the physiological characteristic when the displacement is larger than a predetermined value.

8. The optical finger mouse as claimed in claim 1, further comprising a memory unit configured to store a system frequency calibration parameter.

9. The optical finger mouse as claimed in claim 1, wherein the processing unit is further configured to compare a brightness value of the first image frames and the second image frames with a brightness threshold to identify a contact status of the finger with the optical finger mouse.

10. The optical finger mouse as claimed in claim 9, wherein the displacement and the physiological characteristic are calculated when the contact status is identified as a touch state.

11. The optical finger mouse as claimed in claim 1, wherein the processing unit is configured to calculate the displacement according to two of the first image frames, one of the first image frames and one of the second image frames, and two of the second image frames.

12. The optical finger mouse as claimed in claim 1, wherein

the light control unit is configured to alternatively enable the on-state of the first light source and the second light source such that the image sensor receives the reflected light associated with the first light source and the second light source alternatively;

or

the light control unit is configured to simultaneously enable the on-state of the first light source and the second light source such that the image sensor receives the reflected light associated with the first light source and the second light source simultaneously, and the image sensor comprises an optical filter covering at least a part of a sensing surface thereof.

13. An electronic device configured to calculate and respond to a displacement of a finger of a user and a physiological characteristic of the user, the electronic device comprising:

an optical finger mouse comprising;

two light sources respectively configured to emit light of different wavelengths to the finger;

a light control unit configured to control an on-state and an off-state of the two light sources;

an image sensor configured to capture reflected light from the finger with a sampling frequency to generate a plurality of first image frames and a plurality of second image frames respectively corresponding to the on-state of the two light sources; and

a processing unit configured to calculate both of the displacement of the finger for controlling a cursor and the physiological characteristic according to the first image frames and the second image frames captured by the image sensor, and output the displacement and the physiological characteristic,

wherein in calculating the physiological characteristic, the processing unit is configured to

divide each of the first image frames into at least two parts and calculate an average brightness of each part,

analyze the average brightness of the each part of the first image frames to obtain a first intensity variation,

divide each of the second image frames into at least two parts and calculate an average brightness of each part,

analyze the average brightness of the each part of the second image frames to obtain a second intensity variation, and

calculate the physiological characteristic according to the first intensity variation and the second intensity variation;

a controller configured to receive the displacement and the physiological characteristic; and

a response device controlled by the controller to respond to at least one of the displacement and the physiological characteristic.

14. The electronic device as claimed in claim 13, wherein

the response device is a display device, a lamp device, a seven-segment display or a sound device;

and

the controller is a remote controller, a mouse, a keyboard or an optical distance measuring device.

15. The electronic device as claimed in claim 13, wherein the physiological characteristic comprises a blood oxygenation and a heart rate.

16. The electronic device as claimed in claim 13, wherein the processing unit is further configured to calculate a heart rate according to a comparison of at least one pulse threshold with at least one of the first intensity variation and the second intensity variation.

17. The electronic device as claimed in claim 13, wherein the processing unit is further configured to compare a brightness value of the first image frames and the second image frames with a brightness threshold to identify a contact status of the finger with the optical finger mouse.

18. The electronic device as claimed in claim 17, wherein the displacement and the physiological characteristic are calculated when the contact status is identified as a touch state.

19. A physiological characteristic detection device configured to calculate a physiological characteristic by detecting a part of a human body, the physiological characteristic detection device comprising:

two light sources configured to respectively emit light of different wavelengths to the part of the human body;

a light control unit configured to control an on-state and an off-state of the two light sources;

an image sensor configured to capture reflected light from the part of the human body with a sampling frequency to generate a plurality of first image frames and a plurality of second image frames respectively corresponding to the on-state of the two light sources; and

a processing unit configured to

divide each of the first image frames into at least two parts and calculate an average brightness of each part,

analyze the average brightness of the each part of the first image frames using independent component analysis to obtain a first intensity variation,

divide each of the second image frames into at least two parts and calculate an average brightness of each part,

analyze the average brightness of the each part of the second image frames using independent component analysis to obtain a second intensity variation, and

calculate the physiological characteristic according to the first intensity variation and the second intensity variation.

20. The physiological characteristic detection device as claimed in claim 19, wherein the physiological characteristic comprises a blood oxygenation and a heart rate.