WO1992011608A1 - Formation d'une image d'une empreinte digitale - Google Patents

Formation d'une image d'une empreinte digitale Download PDF

Info

Publication number
WO1992011608A1
WO1992011608A1 PCT/GB1991/002295 GB9102295W WO9211608A1 WO 1992011608 A1 WO1992011608 A1 WO 1992011608A1 GB 9102295 W GB9102295 W GB 9102295W WO 9211608 A1 WO9211608 A1 WO 9211608A1
Authority
WO
WIPO (PCT)
Prior art keywords
light
fingerprint
direct image
major surface
transmitting member
Prior art date
Application number
PCT/GB1991/002295
Other languages
English (en)
Inventor
Alastair Sibbald
Original Assignee
Thorn Emi Plc
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Thorn Emi Plc filed Critical Thorn Emi Plc
Priority to JP4502149A priority Critical patent/JPH06504637A/ja
Publication of WO1992011608A1 publication Critical patent/WO1992011608A1/fr

Links

Classifications

    • G—PHYSICS
    • G06—COMPUTING; CALCULATING OR COUNTING
    • G06V—IMAGE OR VIDEO RECOGNITION OR UNDERSTANDING
    • G06V40/00—Recognition of biometric, human-related or animal-related patterns in image or video data
    • G06V40/10—Human or animal bodies, e.g. vehicle occupants or pedestrians; Body parts, e.g. hands
    • G06V40/12—Fingerprints or palmprints
    • G06V40/13—Sensors therefor
    • G06V40/1324—Sensors therefor by using geometrical optics, e.g. using prisms

Definitions

  • the present invention relates to apparatus and a method for fingerprint imaging.
  • European Patent Application publication number 0,348,182.
  • a method for forming a direct image of a fingerprint comprising; introducing collimated light into a light transmitting member having first and second parallel major surfaces such that the light interacts with the first major surface thereof, in contact with which is a fingerprint to be imaged, the light then reflecting from the first major surface towards the second major surface, optically coupled with which is a direct image producing means, thereby to form a direct image of the fingerprint.
  • both the fingerprint and image thereof lie in parallel planes by virtue of the parallel major surfaces of the light transmitting means, there is no requirement for compensation of'kerbstone' distortion and no need for a large depth-of-field in the image detector means as is the case with prior-art non-direct image formation methods.
  • 'kerbstone' distortion (which is introduced by obliquely viewing an object) will be assumed to be understood by persons skilled in this art.
  • apparatus for forming a direct image of a fingerprint comprising a light transmitting member having a first major surface for receiving a fingerprint and a second major surface, arranged substantially parallel to the first major surface and in optical cooperation with a direct image producing means, the apparatus arranged for receiving collimated light via the second major surface and reflecting from the first major surface thereby to produce a direct image of a fingerprint.
  • the direct image producing means comprises a light. scattering surface such as a ground glass plate member or the like or a very thin layer of paint which is non-opaque, or the like.
  • the direct image producing means is optically-coupled with the light transmitting member, that is, their respective refractive indices match, or they are coupled together using known refractive index matching means, such as a suitable gel, oil or adhesive, then the image producing means is receptive to light impinging thereon and acts as a back- projection viewing screen or "secondary" light source.
  • the direct image producing means comprises fluorescent material. This may take the form of a dye-doped plastics material.
  • the collimated light is introduced into the light transmitting member via a prism means.
  • Advantageously light is reflected from the first major surface toward the second major surface by total internal reflection.
  • Figure 1 shows a schematic representation of a prior art fingerprint imaging device
  • Figure 2 shows a schematic representation of a first embodiment of the present invention
  • Figure 3 shows a schematic representation of a further embodiment of the present invention
  • Figure 4 shows a schematic illustration of yet a further embodiment of the present invention
  • Figure 5 shows a schematic illustration of yet a further embodiment of the present invention.
  • a light source 2 is effective to illuminate a transparent plate 4.
  • a fingerprint characterised by ridges 6 and recesses 8 In contact with the plate 4 is a fingerprint characterised by ridges 6 and recesses 8, the ridges 6 being in contact with the surface of plate 4 and the recesses 8 being spaced from the surface of plate 4 by a series of air gaps.
  • Light entering the plate 4 is randomly reflected by the ridges 6 and is thereby scattered in all directions, since an air gap is not formed at ridges 6.
  • Scattered light beams 10 which satisfy the total internal reflection condition, that is, have an angle of incidence greater than the critical angle, are totally reflected by the lower surface of plate 4. Such beams, only one of which is shown in Figure 1, are then totally reflected by the lower surface of plate 4 and then, following one or more further total internal reflections at upper and lower surfaces, pass through some form of optical element 12, for example a hologram or lens, to be detected by an image sensor 14 arranged outside of the transparent plate 4. This is necessary because the system does not form a direct image of the fingerprint.
  • optical element 12 for example a hologram or lens
  • FIG. 2 illustrates one embodiment of the present invention wherein relatively poor contrast images, as are obtained by such devices as shown in Figure 1, are at least alleviated.
  • the embodiment in Figure 2 comprises a light source 16 and collimating lens 18 arranged to produce a broad collimated light beam 20.
  • This light 20 is introduced into a light transmitting member 22, which is in the form of a transparent substrate such as a glass or plastics plate, via a prism means 24 such as a glass prism optically coupled to one major surface 26 of the light transmitting member 22 by a refractive index coupling medium.
  • a prism means 24 such as a glass prism optically coupled to one major surface 26 of the light transmitting member 22 by a refractive index coupling medium.
  • the prism 24 can be formed integrally with the light transmitting member 22.
  • a second major surface 28 of the light transmitting member is arranged parallel to major surface 26.
  • a finger 30 from which a fingerprint image is to be obtained.
  • fingerprint is to include all anatomical attributes characteristic of an individual which are susceptible to the present method such as thumb-prints, palm-prints and foot-prints. The finger is chosen simply as it is the most convenient by way of example.
  • the angle of incidence, q, at which the collimated light 20 strikes the upper surface 28 against which is placed the finger 30 is arranged to be greater than the critical angle for the medium from which the light transmitting member 22 is formed, such as by appropriately positioning the light source 16 relative to that area of the major surface 28 designated to receive the finger.
  • a direct image producing means 38 in the form of a transparent fluorescent plastics layer material, is in optical cooperation with the lower surface 26 of member 22.
  • the direct image producing means 38 need not be in direct contact with surface 26, in which case some form of refractive index coupling medium may be required.
  • Reflected light 36 passes through the light transmitting member 22 via lower surface 26 and impinges upon the direct image producing means 38.
  • the reflected light 36 is spatially modified as compared with the incident light 20 due to the spatially dependent absorption processes which occur where the light is internally reflected at the upper surface 28 caused by the pressure of ridges 34.
  • the fluorescent dye within the direct image producing means 38 absorbs the reflected light 36 incident thereon within a specific wavelength range (governed by the fluorescent dye) and then re-emits light 40 in a characteristic (of the dye) narrow, longer-wavelength range, as determined by the fluorescent dye.
  • the spatial modulation at this stage is unaffected, that is, the image of the light is unchanged as between that of the fingerprint on upper surface 28 and that produced by the direct image producing means 38.
  • Fluorescence of the dye in the direct image producing means 38 may be enabled not only by the wavelength characteristics of the incident light, but also by the intensity of this light.
  • the image produced will have light areas (caused by fluore ⁇ cence) corresponding to those points on the upper surface 28 underlying fingerprint recesses 32; and dark areas (caused by non-fluorescence) corresponding to those points on the upper surface 28 in contact with fingerprint ridges 34. It will be appreciated that there will be high contrast between these light and dark areas as compared with prior art devices. Because the lower surface 26 and upper surface 28 of the light transmitting member 22 are parallel, then it will be seen that if the direct image producing means 38 is planar, then the plane of emission of light 40 egressing from the direct image producing means 38 is parallel to the object plane; that is, the upper surface 28.
  • the collimated light 20 is introduced into the light transmitting member by way of a prism means in the form of a Fresnel prism strip 44.
  • a prism means in the form of a Fresnel prism strip 44.
  • Figure 3 details the image producing means being in the form of a ground glass plate 46 or thin layer of non-opaque paint applied to the surface 26. Whilst this form of image producing means does not work by fluorescence, the ground glass plate 46 scatters or diffuses the reflected light 36 incident thereon and hence also produces a direct image of the fingerprint.
  • Figure 5 illustrates a further embodiment of the present invention in which the spatially modulated light 36, 36a is permitted to undergo a further total internal reflection at surface 26 before being imaged onto the ground glass plate 46.
  • the direct image produced is viewed by video camera 42 from lower surface 26 via the light transmitting member 22.
  • This particular embodiment allows for the finger- placement surface to be laterally displaced from the imaging screen thereby providing for a compact imaging system. It will be appreciated by those skilled in this art that the present invention provides a compact, relatively slim imaging system by suitable choice of the optical components described herebefore.
  • the image plane that is the fluorescent plastics layer or ground glass or the like is accessible.
  • any optical calibration which may be required, for example alignment of video camera 42 may be achieved by simply inserting some form of reference grid or "test card" over the direct image plane.
  • the present invention requires no focussing or correction elements or the like due to the formation of a direct image. Furthermore, because the invention is relatively simple optically, alignment procedures and assembly costs are not extensive.

Landscapes

  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Optics & Photonics (AREA)
  • Human Computer Interaction (AREA)
  • General Physics & Mathematics (AREA)
  • Multimedia (AREA)
  • Theoretical Computer Science (AREA)
  • Measurement Of The Respiration, Hearing Ability, Form, And Blood Characteristics Of Living Organisms (AREA)
  • Image Input (AREA)

Abstract

On peut former une image directe d'une empreinte digitale en éclairant une surface (26) d'un substrat planaire transparent (22) avec de la lumière collimatée, l'empreinte digitale d'un doigt (30) étant appuyée contre l'autre surface (28) du substrat (22). La lumière incidente sur la surface (26) avec laquelle se trouvent en contact les crêtes de l'empreinte digitale (30) subit une réflexion totale à l'intérieur du substrat (22) et provoque la formation d'une image directe de l'empreinte digitale par la production de lumière fluorescente à l'intérieur d'un élément fluorescent planaire (38).
PCT/GB1991/002295 1990-12-20 1991-12-20 Formation d'une image d'une empreinte digitale WO1992011608A1 (fr)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP4502149A JPH06504637A (ja) 1990-12-20 1991-12-20 指紋描画

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
GB909027718A GB9027718D0 (en) 1990-12-20 1990-12-20 Fingerprint imaging
GB9027718.7 1990-12-20

Publications (1)

Publication Number Publication Date
WO1992011608A1 true WO1992011608A1 (fr) 1992-07-09

Family

ID=10687380

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/GB1991/002295 WO1992011608A1 (fr) 1990-12-20 1991-12-20 Formation d'une image d'une empreinte digitale

Country Status (5)

Country Link
EP (1) EP0563178A1 (fr)
JP (1) JPH06504637A (fr)
CA (1) CA2094599A1 (fr)
GB (1) GB9027718D0 (fr)
WO (1) WO1992011608A1 (fr)

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0609812A1 (fr) * 1993-02-01 1994-08-10 Matsushita Electric Industrial Co., Ltd. Dispositif de transmission d'image à guide d'ondes et dispositif d'identification d'impreintes digitales
WO1996039925A1 (fr) * 1995-06-07 1996-12-19 University Of Arkansas Procede et dispositif pour detecter une reflexion electromagnetique provenant de tissu biologique
US5900993A (en) * 1997-05-09 1999-05-04 Cross Check Corporation Lens systems for use in fingerprint detection
US6111977A (en) * 1997-04-17 2000-08-29 Cross Match Technologies, Inc. Hand-held fingerprint recognition and transmission device
US6178255B1 (en) 1998-04-28 2001-01-23 Cross Match Technologies, Inc. Individualized fingerprint scanner
US6263090B1 (en) 1997-05-19 2001-07-17 Cross Match Technologies, Inc. Code reader fingerprint scanner
US6272562B1 (en) 1999-05-28 2001-08-07 Cross Match Technologies, Inc. Access control unit interface
US8073209B2 (en) 2002-01-17 2011-12-06 Cross Match Technologies, Inc Biometric imaging system and method

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN109959981A (zh) * 2017-12-23 2019-07-02 苏州迈瑞微电子有限公司 光学传感器载片

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE2846190A1 (de) * 1977-10-25 1979-05-03 Michael Schiller Vorrichtung zum verarbeiten einer fingerabdruck betreffenden information
US4340300A (en) * 1980-08-11 1982-07-20 Siemens Corporation Input sensor unit for a fingerprint identification system
EP0308162A2 (fr) * 1987-09-15 1989-03-22 Identix Incorporated Système optique pour imaginer l'empreinte
EP0359554A2 (fr) * 1988-09-16 1990-03-21 Fujitsu Limited Système d'objets biologiques et système de comparaison d'empreintes digitales utilisant ce système

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE2846190A1 (de) * 1977-10-25 1979-05-03 Michael Schiller Vorrichtung zum verarbeiten einer fingerabdruck betreffenden information
US4340300A (en) * 1980-08-11 1982-07-20 Siemens Corporation Input sensor unit for a fingerprint identification system
EP0308162A2 (fr) * 1987-09-15 1989-03-22 Identix Incorporated Système optique pour imaginer l'empreinte
EP0359554A2 (fr) * 1988-09-16 1990-03-21 Fujitsu Limited Système d'objets biologiques et système de comparaison d'empreintes digitales utilisant ce système

Cited By (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0609812A1 (fr) * 1993-02-01 1994-08-10 Matsushita Electric Industrial Co., Ltd. Dispositif de transmission d'image à guide d'ondes et dispositif d'identification d'impreintes digitales
US5448659A (en) * 1993-02-01 1995-09-05 Matsushita Electric Industrial Co., Ltd. Waveguide-type image transmission device and fingerprint identification device
WO1996039925A1 (fr) * 1995-06-07 1996-12-19 University Of Arkansas Procede et dispositif pour detecter une reflexion electromagnetique provenant de tissu biologique
AU706419B2 (en) * 1995-06-07 1999-06-17 University Of Arkansas, The Apparatus for detecting electro-magnetic reflection from biological tissue
US6032070A (en) * 1995-06-07 2000-02-29 University Of Arkansas Method and apparatus for detecting electro-magnetic reflection from biological tissue
US7006861B2 (en) 1995-06-07 2006-02-28 Board Of Trustees Of The University Of Arkansas Method and apparatus for detecting electro-magnetic reflection from biological tissue
US6111977A (en) * 1997-04-17 2000-08-29 Cross Match Technologies, Inc. Hand-held fingerprint recognition and transmission device
US5900993A (en) * 1997-05-09 1999-05-04 Cross Check Corporation Lens systems for use in fingerprint detection
US6263090B1 (en) 1997-05-19 2001-07-17 Cross Match Technologies, Inc. Code reader fingerprint scanner
US6178255B1 (en) 1998-04-28 2001-01-23 Cross Match Technologies, Inc. Individualized fingerprint scanner
US6272562B1 (en) 1999-05-28 2001-08-07 Cross Match Technologies, Inc. Access control unit interface
US8073209B2 (en) 2002-01-17 2011-12-06 Cross Match Technologies, Inc Biometric imaging system and method

Also Published As

Publication number Publication date
EP0563178A1 (fr) 1993-10-06
JPH06504637A (ja) 1994-05-26
CA2094599A1 (fr) 1992-06-21
GB9027718D0 (en) 1991-02-13

Similar Documents

Publication Publication Date Title
US5619586A (en) Method and apparatus for producing a directly viewable image of a fingerprint
US6292576B1 (en) Method and apparatus for distinguishing a human finger from a reproduction of a fingerprint
US4924085A (en) Uneven-surface data detection apparatus
US5187748A (en) Optical apparatus for fingerprint identification system
KR900006061B1 (ko) 요철면 정보 검출장치
US6231200B1 (en) Surface light source device, elements therefor and apparatus using the same
US3527535A (en) Fingerprint observation and recording apparatus
US5822445A (en) Apparatus for identifying fingerprints
KR0155034B1 (ko) 요철면 판독장치
US5629764A (en) Prism fingerprint sensor using a holographic optical element
DE60023156T2 (de) Verfahren und gerät zur verminderung der trapezverzerrung und verbesserung der bildschärfe in einem optischen bilderfassungssystem
JPH10289304A (ja) 指紋画像入力装置
KR101595581B1 (ko) 반사 특성을 가진 물체의 밀리미터 또는 밀리미터 이하의 상세 구조를 관측하기 위한 광학 장치
WO1992011608A1 (fr) Formation d'une image d'une empreinte digitale
CN212084164U (zh) 指纹模组以及电子设备
US6399938B1 (en) Optical device, and imaging unit, imaging apparatus, radiation image sensor, and fingerprint identifying apparatus using the same
EP0098607A2 (fr) Image d'une empreinte digitale
WO1999009514A1 (fr) Capteur dactyloscopique miniature comportant un prisme trapezoidal et un element optique holographique
US4586076A (en) Scanner optics for containing scattered light
JPH03117161A (ja) 光学式原稿走査装置
CN100449566C (zh) 光学指纹输入装置
EP0045917B1 (fr) Détecteur d'empreintes digitales délivrant un signal électrique
JPH11250231A (ja) 凹凸面接触パッドおよび凹凸パターン採取装置
US4968139A (en) Illuminating system for the visual inspection of objects
EP0949577A2 (fr) Medium d'enregistrement d'information et système de lecture d'information

Legal Events

Date Code Title Description
AK Designated states

Kind code of ref document: A1

Designated state(s): CA JP US

AL Designated countries for regional patents

Kind code of ref document: A1

Designated state(s): AT BE CH DE DK ES FR GB GR IT LU MC NL SE

WWE Wipo information: entry into national phase

Ref document number: 1992901705

Country of ref document: EP

WWE Wipo information: entry into national phase

Ref document number: 2094599

Country of ref document: CA

WWP Wipo information: published in national office

Ref document number: 1992901705

Country of ref document: EP

WWW Wipo information: withdrawn in national office

Ref document number: 1992901705

Country of ref document: EP