Hand dimension verification

• US 4,720,869 A
• Filed: 02/18/1986
• Issued: 01/19/1988
• Est. Priority Date: 02/18/1986
• Status: Expired due to Fees

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Wadia, Aspi B.
• Primary Examiner(s): Boudreau, Leo H.
• Assistant Examiner(s): Couso, Jose L.
• Application Number:
  US06/830,772
• Time in Patent Office: 700 Days
• Field of Search: 382/2, 382/4, 382/21, 382/22, 382/23, 382/24, 382/25, 382/58, 382/62, 382/65, 340/825.31, 340/825.34, 250/560, 250/561, 356/2, 356/71, 356/376, 358/199, 358/200, 358/202-207
• US Class Current: 382/115
• CPC Class Codes: G06V 40/10 Human or animal bodies, e.g. vehicle occupants or pedestrians; Body parts, e.g. hands
• CPC Class Codes: G06V 40/11 Hand-related biometrics; Hand pose recognition
• CPC Class Codes: G07C 9/37 using biometric data, e.g. fingerprints, iris scans or voice recognition

Abstract

Improved method and apparatus are provided for hand dimension verification. A two dimensional scanner provides image data from top and angled scans to an image processor which processes this data to develop invariable hand measurements using reference points located from contour sequences generated from the image scan data. The reference points are located so as to be immune from variations introduced by fingernail length, hand pressure and finger spread. Finger width measurements are made using certain reference points and finger width variations are used to determine the presence of abnormalities which could be natural or introduced by wearing of jewelry. The finger width variations are in effect removed by locating finger contour points at the beginning and ending of the variations and using finger slope data for trimming and thereby provide invariable finger width measurements together with finger thickness, finger length and hand area measurements for hand dimension verification.

Claims

1. An improved hand dimension verification system comprising:

a scanner for scanning a hand positioned in a horizontal plane with the fingers thereof spaced apart first at one angle and second at another angle to provide two sets of hand image data, each set being a contour sequence of the entire hand and image processing means for processing said two sets of hand image data to provide hand verification measurements including finger width, finger length, finger thickness and hand area.

2. The improved hand dimension verification system of claim 1 where said first angle is substantially at 90 degrees to the hand and said second angle is substantially at 45 degrees thereto.

3. The improved hand dimension verification system of claim 1 where said finger thickness measurement is a thickness measurement at substantially 45 degrees angle to said horizontal plane.

4. The improved hand dimension verification system of claim 1 wherein said scanner comprises:

an illumination section including a point light source, a lens for converting light from said light source to a bundle of parallel light rays, a first mirror set at an angle for reflecting a portion of light from said light source passed by said lens as a bundle of parallel light rays to illuminate the hand being scanned at one angle and passing another portion of the light, a second mirror set at an angle for reflecting light passed by said first mirror to illuminate the hand being scanned at another angle, and,

a scanning section including a first lens system and a first corresponding parabolic mirror, said first lens system passing light illuminating said hand being scanned at one angle to said first corresponding parabolic mirror, a second lens system and a second corresponding parabolic mirror, said second lens system passing light illuminating said hand being scanned at another angle to said second corresponding mirror, a linear photosensitive array positioned at the focal points of said first and second parabolic mirrors, and a rotating scanning drum encircling said linear photosensitive array and having a slot for first passing light reflected by said first parabolic mirror to said linear photosensitive array and for secondly passing light reflected by said second parabolic mirror to said linear photosensitive array.

5. The improved hand dimension verification system of claim 4 wherein said first mirror is a half silvered mirror.

6. The improved hand dimension verification system of claim 4 wherein said first mirror is set at approximately 45 degree angle.

7. The improved hand dimension verification system of claim 4 wherein said second mirror is set at approximately 67.5 degree angle.

8. The improved hand dimension verification system of claim 4 wherein said linear photosensitive array is in registration with and faces said slot and rotates with said drum.

9. The improved hand dimension verification system of claim 4 wherein said first lens system comprises a first cylindrical lens for converging parallel light rays and a second cylindrical lens for diverging converging light rays to a bundle of parallel light rays having a width corresponding to the width of said linear photosensitive array and said second lens system comprises a first cylindrical lens for converging parallel light rays and a second cylindrical lens for diverging converging light rays into a bundle of parallel light rays having a width corresponding to the width of said linear photosensitive array.

10. The improved hand dimension verification system of claim 1 wherein said scanner comprises:

an illumination section including a point light source, a lens for converting the light from said point light source to a bundle of parallel light rays, a first mirror set at an angle for reflecting a portion of light rays passed by said lens as a bundle of light rays to illuminate the hand being scanned at one angle and passing another portion of the bundle of light rays, a second mirror set at an angle for reflecting light passed by said first mirror to illuminate the hand being scanned at another angle, and

a scanning section including a first lens system and a first parabolic mirror, said first lens system passing light illuminating said hand being scanned at one angle to said first parabolic mirror, a second lens system for passing light illuminating said hand being scanned at another angle, a second mirror positioned in the path of light passed by said second lens system so as to reflect that light to said first parabolic mirror, a linear array of photosensitive elements and a rotating scanning drum encircling said linear array of photosensitive elements and having first and second longitudinal peripheral slots diametrically opposed from each other and having predetermined lengths whereby one slot passes light to said linear array of photosensitive elements passed by said first lens system and reflected by said first parabolic mirror and the other slot passes light to said linear array of photosensitive elements passed by said second lens system and reflected in sequence by said second mirror and said first parabolic mirror.

11. The improved hand dimension verification system of claim 10 wherein said first lens system comprises a first cylindrical lens for converging parallel light rays and a second cylindrical lens for diverging converging light rays into a bundle of parallel light rays having a width corresponding to the width of said linear array of photosensitive elements and said second lens system comprises a first cylindrical lens for converging parallel light rays and a second cylindrical lens for diverging converging light rays into a bundle of parallel light rays having a width corresponding to the width of said linear array of photosensitive elements.

12. The improved hand dimension verification system of claim 10 wherein said first lens system is in a horizontal plane.

13. The improved hand dimension verification system of claim 10 wherein said second lens system is positioned at approximately 45 degree angle.

14. The improved hand dimension verification system of claim 10 wherein said second mirror is in a vertical plane.

15. An improved hand dimension verification system comprising:

a scanner for scanning a hand positioned in a horizontal plane with the fingers thereof spaced apart, first at one angle and second at another angle to provide two sets of hand image data each set being a contour sequence of the entire hand, and,

image processing means for processing said two sets of hand image data in a manner to develop invariant hand measurements.

16. The improved hand dimension verification systems of claim 15 wherein one of said invariant hand measurements is finger length, said finger length being equal to the distance from a first reference point inward of the distal finger end to a second reference point at the interdigit depth adjacent to the proximal finger end.

17. The improved hand dimension verification system of claim 15 wherein one of said invariant hand measurements is finger width, said finger width being equal to the distance from a reference point located inward of the distal finger end and at the base of a line extending parallel to the bisector of an angle formed by a first line extending across the finger and being the perpendicular bisector of a line extending between two points inward of said distal finger end along one edge thereof and a second line extending from a point where said first line intersects the other edge of said finger to said one edge of the finger, said second line being perpendicular to a straight line between said point where said first line intersects the other edge and a point located along said other edge a predetermined distance away. wherein one of said invariant hand measurements is finger thickness at an angle.

18. The improved hand dimension verification system of claim 15 wherein one of said invariant hand measurements is finger thickness at an angle to said horizontal plane.

19. The improved hand dimension verification system of claim 18 wherein said angle is approximately 45 degrees.

20. The improved hand dimension verification system of claim 18 wherein said finger thickness is measured by using image data derived by scanning at said another angle.

21. The improved hand dimension verification system of claim 15 wherein one of said invariant hand measurements is hand area, said hand area being an area bounded by a continuous line having a point of origin located at the base of the hand along the outer contour thereof and continuing along the contour thereof and along the contour of each finger and thumb and then along the base of the hand to said point of origin, the tip of each finger and thumb being truncated by a line joining opposite points inward of the distal end.