Coating processes – Body member printing
Patent
1998-09-18
2000-12-19
Beck, Shrive
Coating processes
Body member printing
427428, 118 315, A61B 5117
Patent
active
061624861
DESCRIPTION:
BRIEF SUMMARY
The invention relates to a process for acquiring fingerprints and to a device for implementing this process.
This invention therefore relates to the field of fingerprint acquisition. It makes it possible to acquire one or more prints simultaneously.
This method makes it possible to acquire prints with reproducibility of print acquisition.
Within the field, there are conventionally two types of fingerprint acquisition devices: applies it to a sheet of paper so as to transfer the image of the ridges and furrows. frustrated total internal reflection of a light wave illuminating an optical dioptre lens (see references 1 and 2 at the end of the description). The person applies his finger to an optical prism consisting of a block of glass. The points of the finger in contact with the prisms (the ridges of the print) perturb the coefficient of reflection by perturbing the index in the vicinity of the interface dioptre lens. The image of the dioptre lens is transmitted to a camera (generally a CCD video camera) which thus records the fingerprint.
The main drawbacks of these devices are the quality, and especially the reproducibility of the acquisition. This second point would appear to be a major problem if it is desired to automate the operations of identification (population monitoring) and authentication (access control) (see references 3, 4 and 5 at the end of the description).
Another drawback of the second device is the cost of the system.
The present patent application proposes to improve the quality of the image (uniform distribution of ink over the finger) and especially the reproducibility of acquisition without a corresponding significant increase in the costs or acquisition time as compared with the conventional method of acquisition with an inking pad. This new process for acquiring fingerprints is based on the passivity of the candidate while the print is being taken in order to solve the acquisition repeatability problem. The flexibility of the plastic which is used makes it possible to carry out an equivalent acquisition in terms of area acquired when the finger is "rolled" over an inking pad, while also ensuring the passivity of the candidate. The device is described below in detail.
The invention therefore relates to a process for acquiring fingerprints, characterized in that it comprises the following steps: whose prints are to be acquired;
The invention also relates to a device for acquiring fingerprints, characterized in that it comprises: or hand whose print it is desired to acquire, or alternatively a recording support;
The various subjects and characteristics of the invention will emerge more clearly from the description which follows and the appended Figures, in which: invention; invention.
The process for acquiring prints according to the invention will be described while referring to FIGS. 1a to 1d.
In general, this process provides for the following main steps: ink; applied against the faces of the fingers. The surface of the pad is made of a material capable of taking up the ink deposited on the fingers; in place of the hand (FIG. 1b); the image of the fingerprints onto the sheet of paper; to use it for a subsequent acquisition.
This cleaning can be done, for example, by spraying a solvent.
In this process, the finger or fingers whose prints are acquired have to be wedged. A support is therefore provided which, for example, takes the form of a plate 1. The face 10 of this plate possesses means for wedging the fingers.
According to FIGS. 2a to 2c, the face 10 possesses a stop 11 which limits the axial displacement of the fingers, and stops such as 12 which are designed to be located on either side of the fingers and which limit the lateral displacement of the fingers. As represented in FIG. 2a, a hand is brought near to the support 1, the back of the hand being on the face 10. The fingers are placed between the stops 12, and the middle finger abuts against the stop 11 (FIG. 2b). An ink coating device, such an ink roller 3, is passed over the faces of the fingers whose prints are to be a
REFERENCES:
patent: 3804524 (1974-04-01), Jocoy et al.
patent: 3824951 (1974-07-01), Le Vantine et al.
patent: 4706600 (1987-11-01), Mason, Jr. et al.
patent: 5599391 (1997-02-01), Lee
"How things work", Granada Publishing Limited, St. Albans and London (GB) , vol.1, (1980), XP002033261, pp. 418-419.
Bricot Claude
Rajbenbach Henri
Samouilhan Stephane
"Thomson-CSF"
Beck Shrive
Crockford Kirsten A.
LandOfFree
Process for acquiring fingerprints and device for implementing t does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Process for acquiring fingerprints and device for implementing t, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Process for acquiring fingerprints and device for implementing t will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-269302