Fingerprint image optical input apparatus

• US 20010050765A1
• Filed: 04/09/2001
• Published: 12/13/2001
• Est. Priority Date: 10/09/1998
• Status: Active Grant

• Current Assignee: Gemalto SA (Thales SA)
• Original Assignee: Geoffrey Vanderkooy, Guy Immega, Keith Antonelli, Timothy Vlaar
• Inventors: Vanderkooy, Geoffrey, Immega, Guy, Antonelli, Keith, Vlaar, Timothy
• Granted Patent: US 6,355,937 B2
• Time in Patent Office: Days
• US Class Current: 356/71
• CPC Class Codes: A61B 5/1172 using fingerprinting
• CPC Class Codes: G06V 40/1324 by using geometrical optics, e.g. using prisms G06V40/1312 takes precedence
• CPC Class Codes: G06V 40/1335 Combining adjacent partial images (e.g. slices) to create a composite input or reference pattern; Tracking a sweeping finger movement
• CPC Class Codes: H01L 2224/48091 Arched
• CPC Class Codes: H01L 2924/00014 the subject-matter covered by the group, the symbol of which is combined with the symbol of this group, being disclosed without further technical details

Abstract

A fingerprint optical input apparatus comprises a contact image sensor for viewing a moving finger and providing a high contrast image. A narrow strip of the fingerprint touching a transparent platen is illuminated by sheet of collimated light normal to or at an oblique angle to the surface. The fingerprint image is viewed at an oblique angle by partially scattered light or by frustrated total internal reflection by a GRIN rod lens array and projected onto a linear array sensor. Various embodiments of the platen provide a compact design by using TIR or mirror reflections of the fingerprint image.

Claims

1. In an imaging apparatus, having a platen (1) composed of a transparent material with an exterior surface for the skin of a finger and an opposed interior surface;

a light source (2), for directing light to or reflecting light off said interior surface of said platen adjacent to the skin of the finger;

a linear sensor array (4); and

a GRIN lens array (3), for focusing the light from the top interior surface of the platen onto the linear sensor array,

the improvement comprising;

(a) said linear sensor array (4) is stationary;

(b) said GRIN lens array (3) is stationary; and

(c) said GRIN lens array (3) is situated at an oblique angle to said platen (1).

5. Imaging apparatus of one of claims 1 through 4, further having multiple parallel linear sensor arrays.

6. Imaging apparatus of one of claims 1 through 5, further having said light from said light source redirected by a reflection on an interior surface of the platen using a mirror or total internal reflection.

7. Imaging apparatus of one of claims 1 through 6, further having the light from the light source redirected by a reflection on an interior surface of the platen which is roughened.

8. Imaging apparatus of one of claims 1 through 7, further having the light from the light source collimated by a lens molded into the platen where the light enters.

9. Imaging apparatus of one of claims 1 through 8, further having a ridge (1b) on the top of the platen, either formed from the platen material or a different optically transparent material.

10. Imaging apparatus of one of claims 1 through 9, further having the light from the platen surface reflected on an interior surface using a mirror or total internal reflection before entering the focus means.

11. Imaging apparatus of one of claims 1 through 10, further having the light from the focusing means reflected on an interior surface using a mirror or total internal reflection before arriving at the linear sensor array.

12. Imaging apparatus of one of claims 1 through 11, further having a reservoir for liquid embedded in the platen surface

13. Imaging apparatus of one of claims 1 through 12, further having blackened faces on the platen.

14. Imaging apparatus of one of claims 1 through 13 further employing a method of sensing and measuring finger motion speed and correcting for geometric errors in the electronic output image.

2. In an imaging apparatus, having a platen (1) composed of a transparent material with an exterior surface for the skin of the finger and an opposed interior surface;

a light source (2) for directing light to or reflecting light off said interior surface of said platen adjacent to the skin of the finger, a linear sensor array (4); and

a GRIN lens array (3), the improvement comprising;

(a) said light is partially scattered; and

(b) said GRIN lens array (3) is situated to focus the light scattered from the top interior surface of the platen onto the linear sensor array.

3. In an imaging apparatus, having a platen (1) composed of a transparent material with an exterior surface for the skin of a finger and an opposed interior surface;

a light source (2), for directing light to or reflecting light off said interior surface of said platen adjacent to the skin of the finger;

a linear sensor array (4); and

a relay lens array (6), for focusing the light from the top interior surface of the platen onto the linear sensor array,

the improvement comprising;

(a) said linear sensor array (4) is stationary;

(b) said relay lens array (6) is stationary; and

(c) said relay lens array (6) is situated at an oblique angle to said platen (1).

4. In an imaging apparatus, having a platen (1) composed of a transparent material with an exterior surface for the skin of the finger and an opposed interior surface;

a light source (2) for directing light to or reflecting light off said interior surface of said platen adjacent to the skin of the finger, a linear sensor array (4); and

a relay lens array (3), the improvement comprising;

(a) said light is partially scattered; and

(b) said relay lens array (6) is situated to focus the light scattered from the top interior surface of the platen onto the linear sensor array.

15. In the method of creating an image of an object with a varied surface, including the steps of:

(a) shining a light from a stationary light source (2) underneath a transparent platen (1);

(b) collecting the resulting total internal reflection and frustrated total internal reflection and partially scattered light and directing it to a linear array sensor (4) to create an electronic image of the object thereon,

the improvement comprising;

(c) moving the object along the stationary platen (1) contemporaneously with said shining.

16. The method of

claim 15

further comprising the step of:

(c) measuring object motion speed and correcting for geometric errors in said electronic image.

17. In the method of creating an image of an object with a varied surface, including the steps of:

(a) shining a light from a stationary light source (2) underneath the platen (1) at an oblique angle to the platen (1);

(b) collecting the resulting light from the platen (1) and directing it to a linear array sensor (4) to create an electronic image of the object thereon

the improvement comprising;

(c) moving the object along the stationary transparent platen (1) contemporaneously with said shining.

18. In an imaging apparatus, including a platen (1) composed of a transparent material with an exterior surface for the skin of a finger and an opposed interior surface;

a light source (2), for directing light to or reflecting light off said interior surface of said platen adjacent to the skin of the finger;

a linear sensor array (4); and

a GRIN lens array (3), for focusing the light from the top interior surface of the platen onto the linear sensor array;

the improvement comprising;

(a) said exterior surface of said platen (1) having one and only one raised portion (1b); and

(b) said GRIN lens array (3) situated at an oblique angle with respect to said platen (1).

20. Imaging apparatus of one of claims 18 or 19, further having multiple parallel linear sensor arrays.

21. Imaging apparatus of one of claims 18 through 20, further having said light from said light source redirected by a reflection on an interior surface of the platen using a mirror or total internal reflection.

22. Imaging apparatus of one of claims 18 through 21, further having the light from the light source redirected by a reflection on an interior surface of the platen which is roughened.

23. Imaging apparatus of one of claims 18 through 22, further having the light from the light source collimated by a lens molded into the platen where the light enters.

24. Imaging apparatus of one of claims 18 through 23, further having a ridge on the top of the platen, either formed from the platen material or a different optically transparent material.

25. Imaging apparatus of one of claims 18 through 24, further having the light from the platen surface reflected on an interior surface using a mirror or total internal reflection before entering the focus means.

26. Imaging apparatus of one of claims 18 through 25, further having the light from the focusing means reflected on an interior surface using a mirror or total internal reflection before arriving at the linear sensor array.

27. Imaging apparatus of one of claims 18 through 26, further having a reservoir for liquid embedded in the platen surface.

28. Imaging apparatus of one of claims 18 through 27, further having blackened faces on the platen.

29. Imaging apparatus of one of claims 18 through 28 further employing a method of sensing and measuring finger motion speed and correcting for geometric errors in the electronic output image.

19. In an imaging apparatus, including a platen (1) composed of a transparent material with an exterior surface for the skin of a finger and an opposed interior surface;

a light source (2), for directing light to or reflecting light off said interior surface of said platen adjacent to the skin of the finger;

a linear sensor array (4); and

a relay lens array (3), for focusing the light from the top interior surface of the platen onto the linear sensor array;

the improvement comprising;

(a) said exterior surface of said platen (1) having one and only one raised portion (1b); and

(b) said relay lens array (3) situated at an oblique angle with respect to said platen (1).

30. In an imaging apparatus, including a platen (1) composed of a transparent material with an exterior surface for the skin of a finger and an opposed interior surface;

a light source (2), for directing light to or reflecting light off said interior surface of said platen (1) adjacent to the skin of the finger;

a linear sensor array (4); and

a GRIN lens array (3) for focusing the light from the top interior surface of the platen (1) onto the linear sensor array (4);

the invention comprising;

(a) said GRIN lens array (3) positioned at least partially within said platen (1).

32. Imaging apparatus of one of claims 30 or 31, further having multiple parallel linear sensor arrays.

33. Imaging apparatus of one of claims 30 through 32, further having said light from said light source redirected by a reflection on an interior surface of the platen using a mirror or total internal reflection.

34. Imaging apparatus of one of claims 30 through 33, further having the light from the light source redirected by a reflection on an interior surface of the platen which is roughened

35. Imaging apparatus of one of claims 30 through 34, further having the light from the light source collimated by a lens molded into the platen where the light enters.

36. Imaging apparatus of one of claims 30 through 35, further having a ridge (1b) on the top of the platen, either formed from the platen material or a different optically transparent material.

37. Imaging apparatus of one of claims 30 through 36, further having the light from the platen surface reflected on an interior surface using a mirror or total internal reflection before entering the focus means.

38. Imaging apparatus of one of claims 30 through 37, further having the light from the focusing means reflected on an interior surface using a mirror or total internal reflection before arriving at the linear sensor array.

39. Imaging apparatus of one of claims 30 through 38, further having a reservoir for liquid embedded in the platen surface.

40. Imaging apparatus of one of claims 30 through 39, further having blackened faces on the platen.

41. Imaging apparatus of one of claims 30 through 40 further employing a method of sensing and measuring finger motion speed and correcting for geometric errors in the electronic output image.

31. In an imaging apparatus, including a platen (1) composed of a transparent material with an exterior surface for the skin of a finger and an opposed interior surface;

a light source (2), for directing light to or reflecting light off said interior surface of said platen (1) adjacent to the skin of the finger;

a linear sensor array (4); and

a relay lens array (3) for focusing the light from the top interior surface of the platen (1) onto the linear sensor array (4);

the invention comprising;

(a) said relay lens array (3) positioned at least partially within said platen (1).