OPTICAL FINGER MOUSE, ELECTRONIC DEVICE AND PHYSIOLOGICAL CHARACTERISTICS DETECTION DEVICE

• US 20130072771A1
• Filed: 09/13/2012
• Published: 03/21/2013
• 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
• Granted Patent: US 9,301,694 B2
• Time in Patent Office: Days
• US Class Current: 600/324
• 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 and a physiological characteristic of a finger, the optical finger mouse comprising:

a first light source emitting light of a first wavelength to the finger;

a second light source emitting 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 the displacement and the physiological characteristic according to the first image frames and the second image frames.

2. The optical finger mouse as claimed in claim 1, wherein the processing unit divides each of the first image frames into at least two parts and calculates an average brightness of each part, and analyzes the average brightness of the each part of the first image frames using independent component analysis to obtain a first intensity variation;

divides each of the second image frames into at least two parts and calculates an average brightness of each part, and analyzes the average brightness of the each part of the second image frames using independent component analysis to obtain a second intensity variation; and

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

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

4. The optical finger mouse as claimed in claim 2, wherein the processing unit further calculates a heart rate according to a comparison result of comparing at least one pulse threshold with at least one of the first intensity variation and the second intensity variation.

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

6. The optical finger mouse as claimed in claim 1, wherein the light control unit enables 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 calculates 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.

7. The optical finger mouse as claimed in claim 1, which enters a sleep mode after idling for a predetermined time period.

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

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

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

11. The optical finger mouse as claimed in claim 1, wherein the processing unit calculates 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 alternatively enables 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 simultaneously enables 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 a displacement and a physiological characteristic of a finger, the electronic device comprising:

an optical finger mouse comprising;

two light sources respectively emitting 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 and output the displacement and the physiological characteristic according to the first image frames and the second image frames;

a controller receiving the displacement and the physiological characteristic; and

a response device controlled by the controller to respond 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 divides each of the first image frames into at least two parts and calculates an average brightness of each part, and analyzes the average brightness of the each part of the first image frames using independent component analysis to obtain a first intensity variation;

divides each of the second image frames into at least two parts and calculates an average brightness of each part, and analyzes the average brightness of the each part of the second image frames using independent component analysis to obtain a second intensity variation; and

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

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

18. The electronic device as claimed in claim 13, wherein the processing unit further compares a brightness value of the first image frames and the second image frames with a brightness threshold to identify a contact status.

19. A physiological characteristic detection device for calculating a physiological characteristic by means of detecting a part of the human body, the physiological characteristic detection device comprising:

two light sources respectively emitting 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, and analyze the average brightness of the each part of the first image frames using independent component analysis to obtain a first intensity variation;

to divide each of the second image frames into at least two parts and calculate an average brightness of each part, and analyze the average brightness of the each part of the second image frames using independent component analysis to obtain a second intensity variation; and

to 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.