Classifications

• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
  • A61B5/00—Measuring for diagnostic purposes; Identification of persons
  • A61B5/117—Identification of persons
  • A61B5/1171—Identification of persons based on the shapes or appearances of their bodies or parts thereof
  • A61B5/1172—Identification of persons based on the shapes or appearances of their bodies or parts thereof using fingerprinting
• • G—PHYSICS
  • G02—OPTICS
  • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
  • G02B13/00—Optical objectives specially designed for the purposes specified below
  • G02B13/08—Anamorphotic objectives
  • G02B13/10—Anamorphotic objectives involving prisms
• • G—PHYSICS
  • G06—COMPUTING OR CALCULATING; 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
• • G—PHYSICS
  • G07—CHECKING-DEVICES
  • G07C—TIME OR ATTENDANCE REGISTERS; REGISTERING OR INDICATING THE WORKING OF MACHINES; GENERATING RANDOM NUMBERS; VOTING OR LOTTERY APPARATUS; ARRANGEMENTS, SYSTEMS OR APPARATUS FOR CHECKING NOT PROVIDED FOR ELSEWHERE
  • G07C9/00—Individual registration on entry or exit
  • G07C9/20—Individual registration on entry or exit involving the use of a pass
  • G07C9/22—Individual registration on entry or exit involving the use of a pass in combination with an identity check of the pass holder
  • G07C9/25—Individual registration on entry or exit involving the use of a pass in combination with an identity check of the pass holder using biometric data, e.g. fingerprints, iris scans or voice recognition

Definitions

• the invention relates to a device for distortion-free imaging of objects aligned with the imaging plane using a reflecting body which is acted upon by a light source and is associated with the object to be imaged, in particular for detecting, examining and identifying fingerprints.
• the object of the invention is to provide a generic device which allows the imaging, viewing, documentation and direct automatic evaluation of objects arranged at an oblique angle to the imaging plane, an identical undistorted impression image being generated without the use of mirrors or mirror-like elements.
• the object is achieved in that the reflecting body is generally designed as a glass body, in particular as a reflection prism, between the reflection prism and the end section on the image side Means an arrangement of deflecting prisms or Ablenkkeilen the field flatness of the object to be imaged, as well as to compensate for the astigmatism and a first and possibly second anamorphic optical lens array is formed '.Hier notebook is achieved the effect that the flatness of field located by the first deflection prism through the second to the lens Deflection prism is lifted less than the compensation of the astigmatism, whereby both deflection prisms in combination enable a flattening of the image field without the occurrence of astigmatism at a close image and object level.
• the very high contrast and the smudge-free and stain-free image enable automatic evaluation.
• the finger strips enables a more secure evaluation of different types of finger strip features. Due to the simple handling, errors in taking impressions are eliminated.
• the simple design of the optical system is very robust and insensitive to mechanical influences such as vibrations and can also be made relatively small and light.
• the device according to the invention is easy to transport. Since only a few optical components are required, the manufacturing costs are relatively low.
• a further advantage is the possibility of being able to connect commercially available or specific imaging or recording devices. With a concavely curved contact surface on the reflection prism, it is also possible to be able to detect curved objects with one receptacle.
• Fig. 1 shows the device according to the invention in a perspective view from above
• FIG. 2 shows the device according to FIG. 1 in a diagrammatic view of the housing section having the reflection prism
• FIG. 3 d optical device of the device of FIG. 1 in a schematic perspective view
• FIGS. 1 and 2 shows the optical device of the device according to FIGS. 1 and 2 in a schematic side view
• Fig. 4c shows an embodiment of the device
• FIG. 5a shows a further embodiment of the device according to FIG. 1 with a fiberboard for flattening the image in a schematic side view
• the device 25 has a housing 24 with an object-side end section 22 and an imaging-side end section 23 (FIGS. 1 and 2).
• the bearing surface 6 of the reflection prism 4 is formed on the object-side end section 22.
• a connection means 19 is provided on the imaging-side end section 23 in order to be able to connect a connection member 20 such as an extension part, an optical reproduction device or an optical evaluation device.
• the optical arrangement of the device 25 consists of a reflection prism 3, a deflection prism 8 for leveling the image field, which is also known conceptually as an anamorphic magnification, a deflection prism 13 for eliminating the astigmatism, and an optical lens 17 (FIG. 4a ).
• An illumination device 1 is arranged in front of the light incidence surface 4 of the reflection prism 3. There is a diffusing screen 2 between the lighting device 1 and the light incidence surface 4 to make the light rays more uniform.
• the base of the reflection prism 3 is designed as a support surface 6 on which the object 7 to be imaged, such as. B. a finger must be placed.
• the deflection prism 8 for flattening the field of view is arranged in relation to the reflection prism 3 in such a way that the light incidence surface 9 and the light emission surface 10 of the deflection prism 8 are arranged at an acute angle to one another and obliquely to the light emission surface 5 of the reflection prism 3.
• the prism base 11 of the deflection prism 8 is oriented away from the outer beam path 12 at an obtuse angle to the light-emitting surface 5 of the reflection prism 3.
• the light incident surface 14 and light incident surface 15 of the deflecting prism 13 is oriented obliquely to the light incident surface 10 of the deflecting prism 8 such that the prism base 16 is at a greater distance from the light incident surface 10 than the tip section of the deflecting prism 13-
• an effective housing 18 is indicated, on which a connecting means 19 for connecting members 20 is formed.
• the deflection prism 8 at a certain prism angle and corresponding position of this deflection prism 8 relative to the reflection prism 3 and to the lens 17 cancels out the perspective distortion that occurs when, as required, at an angle looks at the reflecting hypotenuse surface from about 45 ° through one of the two sides of the catheter.
• the deflection prism 8 thus brings about a flattening of the image field, which counteracts or eliminates the perspective distortion. This process is shown schematically in Fig. 4b.
• this deflection prism 8 can at the same time compensate for a difference in depth of focus that arises from such a perspective view.
• the field of view is flattened.
• the deflecting prism 13 > which is at a distance from the light-emitting surface 10 of the deflecting prism 8 and which has a considerably smaller prism angle than the first deflecting prism 8 serves primarily for that indicated by the outer one during the passage of rays
• the parameters of the optical system are also determined by the length of the objective tube adjoining the lens 17 or a device with a similar function and the focal length of the lens 17.
• the device 25 thus makes it possible to switch off or compensate for the astigmatism in the near object plane and near image plane. There are no differences in the meridional and sagittal focal lengths.
• the Device have a concavely curved support surface 6 on the reflection prism 3.
• the lens arrangement 37 can consist of an optical lens 17 and an optical lens 38.
• FIG. 4c shows the light-optical beam path 27 of an experimentally designed embodiment of the device 25.
• the intermediate beams 29 are guided on the output side through a lens arrangement 37, which consists of the optical lenses 17, 38, 39.
• This device 30 consists of a reflection prism 3 with a concave support surface 6, which is thus designed as a support prism.
• This reflection prism 3 is followed by two deflection prisms 8, 13, behind which the anamorphic lens arrangement 36 consisting of the anamorphic lenses 32, 33, 34 is formed.
• the anamorphic lens arrangement 37 consists of the light-optical anamorphic lenses 17, 38, 39.
• the optical rays 29 emerging from the lens 39 are fed through an opening 41 in the housing 21 to a cylindrical lens 40, behind which there are light-optical properties having fiberboard 35 is arranged. It is also possible to use this fiberboard 35 or another fiberboard 35 within the
• a fiberboard 35 can also be provided behind the reflection prism 3. It is also possible to use only phaser plates 35 instead of the anamorphic Lisen arrangements 36, 37. By appropriately inserting an upstream, intermediate or downstream special optical system with at least one fiberboard 35, either the entire image field leveling or only a remaining image leveling that is still required can be effected.
• the bearing surface 6 of the reflection prism 3 can be made differently concave, depending on which object such. B. fingers are placed on the support surface 6. It is also possible to provide a plurality of contact surfaces 6 with different concave curvature on the object-side end section 22 of the device 25, 30. As indicated in Fig. 2 by dashed lines
• Support surface 6 are also formed by appropriately trained convex, concave or flat surface sections so that a whole hand on the Support surface 6 can be placed.
• the lighting device 1 is designed such that the support surface 6 can be illuminated uniformly.

Landscapes

• Physics & Mathematics (AREA)
• Engineering & Computer Science (AREA)
• Health & Medical Sciences (AREA)
• General Physics & Mathematics (AREA)
• Life Sciences & Earth Sciences (AREA)
• Human Computer Interaction (AREA)
• Optics & Photonics (AREA)
• Pathology (AREA)
• Molecular Biology (AREA)
• Biophysics (AREA)
• Multimedia (AREA)
• Biomedical Technology (AREA)
• Heart & Thoracic Surgery (AREA)
• Medical Informatics (AREA)
• Theoretical Computer Science (AREA)
• Surgery (AREA)
• Animal Behavior & Ethology (AREA)
• General Health & Medical Sciences (AREA)
• Public Health (AREA)
• Veterinary Medicine (AREA)
• Lenses (AREA)
• Facsimile Scanning Arrangements (AREA)
• Optical Elements Other Than Lenses (AREA)

Applications Claiming Priority (2)

Publications (1)

Family

ID=6237845

Family Applications (1)

Country Status (3)

Families Citing this family (10)

Family Cites Families (3)

• 1984
  • 1984-06-07 DE DE19843421220 patent/DE3421220A1/de active Granted
• 1985
  • 1985-05-29 EP EP85902474A patent/EP0182827A1/de not_active Withdrawn
  • 1985-05-29 WO PCT/DE1985/000183 patent/WO1986000009A1/de unknown

Non-Patent Citations (1)

Also Published As

Similar Documents

Legal Events