Method and system for optical imaging using patterned illumination

• US 10,115,000 B2
• Filed: 12/11/2015
• Issued: 10/30/2018
• Est. Priority Date: 12/11/2015
• Status: Active Grant

• Current Assignee: Fingerprint Cards AB
• Original Assignee: Synaptics Incorporated
• Inventors: Mackey, Bob Lee, Fomani, Arash Akhavan, Lau, Francis
• Primary Examiner(s): Alavi, Amir
• Application Number:
  US14/966,806
• Publication Number:
  US 20170169275A1
• Time in Patent Office: 1,054 Days
• CPC Class Codes: G06V 40/1318 using electro-optical elements or layers, e.g. electroluminescent sensing
• CPC Class Codes: G09G 2360/145 the light originating from the display screen
• CPC Class Codes: G09G 3/3406 Control of illumination source illumination devices structurally associated with liquid crystal cells G02F1/1336
• CPC Class Codes: G09G 3/3426 the different display panel areas being distributed in two dimensions, e.g. matrix

Abstract

Systems and methods for optical imaging are disclosed. An electronic device for imaging an input object includes a display comprising a sensing surface and an array of display pixels. The electronic device also includes a processing system communicatively coupled to the display, the processing system configured to: selectively illuminate one or more of the display pixels according to a pattern; acquire image data, from one or more detector pixels of the display, of the input object in contact with the sensing surface, wherein the image data corresponds to light from the illuminated display pixels that is reflected at the sensing surface of the display; and process an image of the input object from the image data based upon the pattern.

Claims

1. An electronic device for imaging an input object, comprising:

a display comprising a sensing surface and an array of display pixels;

a processing system communicatively coupled to the display, the processing system configured to;

selectively illuminate one or more of the display pixels according to a pattern;

acquire image data, from one or more detector pixels of the display, of the input object in contact with the sensing surface, wherein the image data corresponds to light from the illuminated display pixels that is reflected at the sensing surface of the display; and

process an image of the input object from the image data based upon the pattern,

wherein the processing system is configured to select the one or more detector pixels from a region surrounding the illuminated display pixels, the region being inside of an outer boundary that is defined by a first critical angle resulting from an interface between a surface of the input object and the sensing surface.

2. The electronic device of claim 1, wherein the input object is a biometric object.

3. The electronic device of claim 1, wherein the processing system is further configured to:

illuminate a portion of the display which at least partially surrounds the object in contact with the sensing surface such that the illuminated portion is visually perceptible.

4. The electronic device of claim 1, wherein the processing system is further configured to detect a condition of the input object by detecting a position of a high contrast region.

5. The electronic device of claim 1, wherein the processing system is further configured to detect presence of the input object and initiate the illumination of the display pixels based on the detected presence.

6. An electronic device for imaging an input object, comprising:

a display comprising a sensing surface and an array of display pixels;

a processing system communicatively coupled to the display, the processing system configured to;

selectively illuminate one or more of the display pixels according to a pattern;

acquire image data, from one or more detector pixels of the display, of the input object in contact with the sensing surface, wherein the image data corresponds to light from the illuminated display pixels that is reflected at the sensing surface of the display; and

process an image of the input object from the image data based upon the pattern,

wherein the processing system is configured to select the one or more detector pixels from a region surrounding the illuminated display pixels, the region being outside of an inner boundary that is defined by a second critical angle resulting from an interface between air and the sensing surface.

7. An electronic device for imaging an input object, comprising:

a display comprising a sensing surface and an array of display pixels;

a processing system communicatively coupled to the display, the processing system configured to;

selectively illuminate one or more of the display pixels according to a pattern;

acquire image data, from one or more detector pixels of the display, of the input object in contact with the sensing surface, wherein the image data corresponds to light from the illuminated display pixels that is reflected at the sensing surface of the display; and

process an image of the input object from the image data based upon the pattern,

wherein the processing system is configured to select the one or more detector pixels from a high contrast annular region surrounding the illuminated display pixels, the high contrast annular region being between an outer boundary and an inner boundary, the outer boundary defined by a first critical angle resulting from an interface between a surface of the input object and the sensing surface and the inner boundary being defined by a second critical angle resulting from an interface between air and the sensing surface.

8. An electronic device for imaging an input object, comprising:

a display comprising a sensing surface and an array of display pixels;

a processing system communicatively coupled to the display, the processing system configured to;

selectively illuminate one or more of the display pixels according to a pattern;

acquire image data, from one or more detector pixels of the display, of the input object in contact with the sensing surface, wherein the image data corresponds to light from the illuminated display pixels that is reflected at the sensing surface of the display; and

process an image of the input object from the image data based upon the pattern,

wherein the pattern is time varying such that illumination of a first set of one or more display pixels is temporally spaced from illumination of a second set of one or more display pixels.

9. An electronic device for imaging an input object, comprising:

a display comprising a sensing surface and an array of display pixels;

a processing system communicatively coupled to the display, the processing system configured to;

selectively illuminate one or more of the display pixels according to a pattern;

acquire image data, from one or more detector pixels of the display, of the input object in contact with the sensing surface, wherein the image data corresponds to light from the illuminated display pixels that is reflected at the sensing surface of the display; and

process an image of the input object from the image data based upon the pattern,

wherein the pattern is spatial and wherein the illuminate one or more display pixels further comprises;

illuminate a first set of one or more display pixels; and

simultaneously illuminate a second set of one or more display pixels, wherein the first set of one or more display pixels is physically spaced apart from the second set of one or more display pixels.

10. An electronic device for imaging an input object, comprising:

a display comprising a sensing surface and an array of display pixels;

a processing system communicatively coupled to the display, the processing system configured to;

selectively illuminate one or more of the display pixels according to a pattern;

acquire image data, from one or more detector pixels of the display, of the input object in contact with the sensing surface, wherein the image data corresponds to light from the illuminated display pixels that is reflected at the sensing surface of the display; and

process an image of the input object from the image data based upon the pattern,

wherein the illuminate one or more of the display pixels further comprises;

illuminate a first set of one or more display pixels; and

illuminate a second set of one or more display pixels, wherein the first set of one or more display pixels is physically spaced apart from the second set of one or more display pixels;

wherein the acquire the image data further comprises;

acquire partial image data from a first set of detector pixels during illumination of the first set of one or more display pixels; and

acquire partial image data from a second set of detector pixels during illumination of the second set of one or more display pixels; and

wherein the process the image comprises;

combine the partial image data from the first set of detector pixels and the partial image data from the second set of detector pixels into composite image data.

11. The electronic device of claim 10, wherein the processing system is further configured to:

compare the composite image data to an enrolled fingerprint template to determine a biometric match.

12. An electronic device for imaging an input object, comprising:

a display comprising a sensing surface and an array of display pixels;

a processing system communicatively coupled to the display, the processing system configured to;

selectively illuminate one or more of the display pixels according to a pattern;

acquire image data, from one or more detector pixels of the display, of the input object in contact with the sensing surface wherein the image data corresponds to light from the illuminated display pixels that is reflected at the sensing surface of the display; and

process an image of the input object from the image data based upon the pattern,

wherein the illuminate one or more of the display pixels further comprises;

illuminate a first set of one or more display pixels; and

illuminate a second set of one or more display pixels, wherein the first set of one or more display pixels is physically spaced apart from the second set of one or more display pixels;

wherein the acquire the image data further comprises;

acquire partial image data from a first set of detector pixels during illumination of the first set of one or more display pixels; and

acquire partial image data from a second set of detector pixels during illumination of the second set of one or more display pixels; and

wherein the process the image comprises;

combine the partial image data from the first set of detector pixels and the partial image data from the second set of detector pixels into composite image data,

wherein the combine the partial image data further comprises;

determine an alignment between the partial image data from the first set of detector pixels and the partial image data from the second set of detector pixels based on a known spatial relationship between the first set of one or more display pixels and the second set of one or more display pixels.

13. An electronic device for imaging an input object, comprising:

a display comprising a sensing surface and an array of display pixels;

a processing system communicatively coupled to the display, the processing system configured to;

selectively illuminate one or more of the display pixels according to a pattern;

acquire image data, from one or more detector pixels of the display, of the input object in contact with the sensing surface wherein the image data corresponds to light from the illuminated display pixels that is reflected at the sensing surface of the display; and

process an image of the input object from the image data based upon the pattern,

wherein the processing system is further configured to detect a condition of the input object by detecting a position of a high contrast region, and

wherein the condition is a moisture condition.

14. An electronic device for imaging an input object, comprising:

a display comprising a sensing surface and an array of display pixels;

a processing system communicatively coupled to the display, the processing system configured to;

selectively illuminate one or more of the display pixels according to a pattern;

acquire image data, from one or more detector pixels of the display, of the input object in contact with the sensing surface, wherein the image data corresponds to light from the illuminated display pixels that is reflected at the sensing surface of the display; and

process an image of the input object from the image data based upon the pattern,

wherein the processing system is further configured to determine a thickness of a cover layer by detecting an inner edge of a high contrast region.

15. An electronic device for imaging an input object, comprising:

a display comprising a sensing surface and an array of display pixels;

a processing system communicatively coupled to the display, the processing system configured to;

selectively illuminate one or more of the display pixels according to a pattern;

acquire image data, from one or more detector pixels of the display, of the input object in contact with the sensing surface, wherein the image data corresponds to light from the illuminated display pixels that is reflected at the sensing surface of the display; and

process an image of the input object from the image data based upon the pattern,

wherein the display further comprises an array of detector pixels distinct from the array of display pixels.

16. An electronic device for imaging an input object, comprising:

a display comprising a sensing surface and an array of display pixels;

a processing system communicatively coupled to the display, the processing system configured to;

selectively illuminate one or more of the display pixels according to a pattern;

acquire image data, from one or more detector pixels of the display, of the input object in contact with the sensing surface, wherein the image data corresponds to light from the illuminated display pixels that is reflected at the sensing surface of the display; and

process an image of the input object from the image data based upon the pattern,

wherein the one or more detector pixels are one or more reverse-biased display pixels from the array of display pixels.

17. An electronic device for imaging an input object, comprising:

a processing system configured to be communicatively coupled to a display, wherein the processing system is further configured to;

selectively illuminate one or more display pixels of the display according to a pattern;

acquire image data, from one or more detector pixels of the display, of the input object in contact with a sensing surface of the display, wherein the image data corresponds to light from the illuminated display pixels that is reflected at the sensing surface of the display; and

process an image of the input object from the image data based upon the pattern,

wherein the processing system is configured to select the one or more detector pixels from a high contrast annular region surrounding the illuminated display pixels, the high contrast annular region being between an outer boundary and an inner boundary, the outer boundary defined by a first critical angle resulting from an interface between a surface of the input object and the sensing surface and the inner boundary being defined by a second critical angle resulting from an interface between air and the sensing surface.

18. An electronic device for imaging an input object, comprising:

a processing system configured to be communicatively coupled to a display, wherein the processing system is further configured to;

selectively illuminate one or more display pixels of the display according to a pattern;

acquire image data, from one or more detector pixels of the display, of the input object in contact with a sensing surface of the display, wherein the image data corresponds to light from the illuminated display pixels that is reflected at the sensing surface of the display; and

process an image of the input object from the image data based upon the pattern,

wherein the illuminate one or more of the display pixels further comprises;

illuminate a first set of one or more display pixels; and

illuminate a second set of one or more display pixels, wherein the first set of one or more display pixels is physically spaced apart from the second set of one or more display pixels;

wherein the acquiring the image data further comprises;

acquire partial image data from a first set of detector pixels during illumination of the first set of one or more display pixels; and

acquire partial image data from a second set of detector pixels during illumination of the second set of one or more display pixels; and

wherein the process the image comprises;

combine the partial image data from the first set of detector pixels and the partial image data from the second set of detector pixels into composite image data.

19. The electronic device of claim 18, wherein the combine the partial image data further comprises:

determine an alignment between the partial image data from the first set of detector pixels and the partial image data from the second set of one or more detector pixels based on a known spatial relationship between the first set of one or more display pixels and the second set of one or more display pixels.

20. A method for imaging an input object comprising:

selectively illuminating one or more display pixels of a display according to a pattern;

acquiring image data, at one or more detector pixels of the display, of the object in contact with a sensing surface of the display, wherein the image data corresponds to light from the illuminated display pixels that is reflected at the sensing surface of the display; and

processing an image of the object from the image data based on the pattern,

wherein the one or more detector pixels are selected from a high contrast annular region surrounding the illuminated display pixels, the high contrast annular region being between an outer boundary and an inner boundary, the outer boundary defined by a first critical angle resulting from an interface between a surface of the input object and the sensing surface and the inner boundary being defined by a second critical angle resulting from an interface between air and the sensing surface.

21. A method for imaging an input object comprising:

selectively illuminating one or more display pixels of a display according to a pattern;

acquiring image data, at one or more detector pixels of the display, of the object in contact with a sensing surface of the display, wherein the image data corresponds to light from the illuminated display pixels that is reflected at the sensing surface of the display; and

processing an image of the object from the image data based on the pattern,

wherein the illuminating one or more of the display pixels further comprises;

illuminating a first set of one or more display pixels; and

illuminating a second set of one or more display pixels, wherein the first set of one or more display pixels is physically spaced apart from the second set of one or more display pixels;

wherein the acquiring the image data further comprises;

acquiring partial image data from a first set of detector pixels during illumination of the first set of one or more display pixels; and

acquiring partial image data from a second set of detector pixels during illumination of the second set of one or more display pixels; and

wherein the processing the image comprises;

combining the partial image data from the first set of detector pixels and the partial image data from the second set of detector pixels into composite image data.

22. The method of claim 21, wherein the combining the partial image data further comprises:

determining an alignment between the partial image data from the first set of detector pixels and the partial image data from the second set of one or more detector pixels based on a known spatial relationship between the first set of one or more display pixels and the second set of one or more display pixels.

23. The method of claim 21, further comprising:

comparing the composite image data to an enrolled fingerprint template to determine a biometric match.

24. An electronic device for imaging a fingerprint, comprising:

a display comprising a sensing surface, an array of display pixels and an array of detector pixels;

a processing system communicatively coupled to the display, the processing system configured to;

illuminate a first set of one or more of the display pixels and illuminate a second set of one or more of the display pixels;

acquire partial image data from a first set of the detector pixels during illumination of the first set of one or more display pixels and acquire partial image data from a second set of the detector pixels during illumination of the second set of one or more display pixels, wherein the first set of detector pixels is selected from a first region surrounding the first set of one or more display pixels, wherein the second set of detector pixels is selected from a second region surrounding the second set of one or more display pixels;

combine the partial image data from the first set of detector pixels and the partial image data from the second set of detector pixels into composite fingerprint image data; and

compare the composite fingerprint image data to an enrolled fingerprint template to determine a biometric match.

25. The electronic device of claim 24, wherein the first region and the second region each have an outer boundary based on a first critical angle resulting from an interface between a ridge of the fingerprint and the sensing surface and an inner boundary based on a second critical angle resulting from an interface between a valley of the fingerprint and the sensing surface.

26. A method for imaging a fingerprint, the method comprising:

illuminating a first set of one or more display pixels of a display and illuminating a second set of one or more display pixels of the display;

acquiring partial image data from a first set of detector pixels of the display during illumination of the first set of one or more display pixels and acquiring partial image data from a second set of detector pixels of the display during illumination of the second set of one or more display pixels, wherein the first set of detector pixels is selected from a first region surrounding the first set of one or more display pixels, wherein the second set of detector pixels is selected from a second region surrounding the second set of one or more display pixels;

combining the partial image data from the first set of detector pixels and the partial image data from the second set of detector pixels into composite fingerprint image data; and

comparing the composite fingerprint image data to an enrolled fingerprint template to determine a biometric match.