KR20010099911A - Device for identifying a person - Google Patents

Abstract

The present invention relates to an apparatus for identifying an individual while using at least one fingerprint. The apparatus includes at least one light source for illuminating and / or seeing the front part of the finger while using a light pulse, and at least one optical fiber finger support surface for acquiring an optical image of the fingerprint. Using the finger support surface, the optical image may be transmitted to at least one sensor unit, and the optical image may be converted into an electrical signal in the sensor unit. At least one light source is disposed on one side of the finger support surface, and the light can be radiated by the light source in the lateral direction of the finger support surface, which serves to support the front face of the finger while being directed in the opposite direction from the sensor unit. have. The duration and / or intensity of the light pulses emitted by the at least one light source can be adjusted depending on the ambient light conditions.

Description

Personal Identification Device {DEVICE FOR IDENTIFYING A PERSON}

The present invention provides a device for personal identification using at least one fingerprint,

Using at least one light source to illuminate and / or view the front part of the finger using light pulses, and

At least one optical fiber finger support surface for receiving an optical image of a fingerprint, through which the optical image can be transmitted to at least one sensor unit, wherein the optical image is an electrical signal. Switchable,

At the same time, at least one light source is arranged on the side of the finger support surface, and the light of the light source is directed in the opposite direction of the sensor unit, and is capable of being radiated on the side of the finger support surface provided to support the front part of the finger. It relates to an identification device.

The devices serve to read and process fingerprints and can be used in all areas where personal identification is required.

The above areas may be, for example, computer technology, licensing systems, crime prevention, medicine, general protection systems, and banking and finance.

Conventionally, in the area of the personal identification device using at least one fingerprint, it includes a light source disposed above the finger to be viewed, whereby the light source and the finger support surface are supported when the finger is supported on the finger support surface. Systems which are located in between are known (compare International Publication WO 98/27509). The light emitted from the light source passes through the front part of the finger, and after receiving the information related to the fingerprint, reaches the sensor unit disposed below the finger support surface through the optical fiber of the finger support surface, and then the rear of the sensor unit. It is analyzed using an evaluation unit that is placed in the.

However, with regard to such a so-called direct optical method, it has been proved as an obvious problem that an individual to be identified using his fingerprint must insert the corresponding finger in the cavity or opening between the light source and the finger support surface.

The above is clearly unsuitable from the psychological aspect of the user and in a significant way according to the invention raises the escape threshold using a general device, because the individual to be identified is, say, the front of the finger. As long as it is exposed in form, it is necessary to insert the body part into a cavity that cannot be visually recognized because this causes an increase in anxiety.

The above-mentioned problem of psychological coping is not addressed in the case of a general device for the input of non-uniform specimens (DE 44 04 918 A1). The device comprises one optical-fiber bundle, each having one incident face and one emitting face formed at both ends of the bundle. The illumination device is configured to emit radiation light in such a way that a light sample is formed in contact with the incident surface corresponding to the blocked portion of the object and correspondingly to the concave portion of the object without contacting the incident surface. Emits. If the angle of incidence of the emission light is adjusted to be greater than the critical angle at the interface between the core part of each optical fiber of the fiber bundle and the air, then total reflection at the entrance plane where there is no contact with the concave portion of the object reflection, and total reflection cannot be achieved at the plane of incidence where it contacts the convex part of the object. This point results in reflecting light with a light sample corresponding to the non-uniform sample. The generated photosamples are input into a photoelectric conversion device through the radiation plane and are converted into electrical information by the conversion device.

However, the device known from DE 44 04 918 A1 proves to be disadvantageous only in that the device operates with a constant intensity of light and is based on the principle of disturbed total reflection. This makes the light conduction as well as the light type inflexible, non-refractive, since the photoelectric converter supersaturates too quickly when the ambient light is approximately 3,000 Lux, which is why This is because no more reliable results can be achieved.

The object of the present invention to solve the above problems is to enable the illumination of the front face of the finger with a reliable and sufficient result, and also to recover the personal identification process for the individual to be identified, as well as being fully identifiable by the personal identification device. It can be as easy as possible, and finally based on continuing to provide in one way a general personal identification device capable of achieving a consistently good and reliable result at all times, regardless of each ambient light condition.

This object is solved in the opening paragraph of the representative claim, in which the duration and / or intensity of the light pulses emitted from the at least one light source is controlled in dependence upon the ambient light conditions in accordance with the inventive arrangements.

Therefore, for the expert, adaptive light control (= ALR or ALC = "adaptive light control"), that is, a kind of "intelligent light control", is provided in an unpredictable manner, which is roughly modified by the control. While the deficiency of changing ambient light conditions, such as indoor lighting being changed or the amount of solar radiation being changed, is adjustable, the device according to the invention or the algorithm controlling the device is adapted to the respective light conditions.

In this connection, in the device according to the invention, at least one control means for adjusting the duration and / or intensity of the light pulses is provided. While using the control device, continuous or temporary measuring methods are feasible, permanently good image quality can be measured using the measuring method and optimally adjusted to contrast and focal depth if necessary. The saturated saturation can be achieved through a short time light pulse, while at the same time the light time pulse is precisely adjusted to the amount of light actually needed in its period and / or its intensity.

According to a preferred embodiment of the invention the control device is:

At least one detecting modul for detecting ambient light conditions, which can be formed integrally with the sensor unit and / or as part of the sensor unit;

An optical pulse, adapted to the ambient light conditions detected from the detection module, which can preferably be formed integrally with at least one evaluation unit arranged behind the sensor unit and / or as part of at least one evaluation unit At least one evaluation module for determining a duration and / or intensity of the; And

Preferably determined for controlling the duration and / or intensity of the light pulses, which may be formed integrally with at least one storage unit arranged behind the sensor unit and / or as part of at least one storage unit. At least one storage module for storing the threshold value is included.

In this regard, the operating method and function of the control device is, for example, that the detection module detects respective ambient light conditions, the conditions are evaluated and analyzed in the evaluation module, and the dictionary stored in the storage module in the evaluation module. The comparison is made with a set threshold.

Subsequent to the result of the comparison, the control device reacts to the control device, and in particular in this case to the light source connected to the evaluation module, at the same time the duration and / or intensity of the light pulses emitted from the light source It is adapted to ambient light conditions.

In this way, the light pulse is not only in its duration but also in its intensity, all types of ambient light (e.g. strong, weak, subdued light, diffused light, incandescent gas light, moonlight, artificial light, It can be formed dynamically and adaptively so that the incident light radiation required for ...) can be obtained while the image of the high contrast and the depth of focus of the fingerprint can be obtained.

In particular, it is possible to realize illuminance from zero Lux to approximately 40,000 Lux while using adaptive light control, and at the same time the maximum illuminance value is approximately direct solar radiation. The results achievable using the adaptive light control have an elevation of contrast and depth of focus of up to approximately 80% compared to conventional lighting systems with steady light, while at the same time light control of the type according to the invention. When the lighting conditions are changed, it is possible to supply the required amount of light in a time zone less than 100 milliseconds, freely using, thereby achieving an image quality that remains nearly uniform for all conceivable light conditions. Has the advantage.

So the practical advantage of the device according to the invention is found in "intelligent control". The intelligent control reliably adjusts the amount of light emitted by itself as needed, and freely calculates the amount of light separately for each area around the object to be illuminated, i.e. approximately around the front of the finger. Thus, overexposure or underexposure with a probability limited to safety is excluded.

In this association, certain lighting units, such as those provided in conventional devices for personal identification using at least one fingerprint, have the disadvantage that the amount of light supplied from them cannot be emitted in relation to the object, ie 5 millimeters. By illuminating a 10-millimeter-thick object with the same amount of light as the object of thickness, there is a disadvantage in that it is not clear, but partial overexposure is realized.

In contrast, the present invention allows for uniform illumination of one object, ie approximately the front of the finger, and, precisely, regardless of the thickness of the object, which may typically include rather strong light conductivity or rather strong reflectivity as a whole, and Enables uniform illumination regardless of whether the object is illuminated by unwanted light at the front, side and / or back. As a result, in the case of the present invention, whether or not light is emitted to an object to be illuminated from which angle and from which position does not play any role; Only additionally necessary light duration and / or intensity should be adjusted individually for each region.

Finally, as an advantage of the adaptive light control of the present invention, the finger image can be measured with the contrast and the depth of focus acquired over the entire range without actually changing the illumination time.

Suitably for the purpose the adaptive light control controller is at least one logic element and / or at least one logic circuit, in particular at least one standard logic element or at least one programmable It is formed as a logic circuit (FPGA = field programmable gate array). The control device may also be configured as at least one digital signal processing unit (DSP = digital signal processor) and / or as at least one microcontroller in an alternative way or in addition to the above.

As in the above-described embodiment, the control device provided for performing the adaptive light control includes at least one detection module, at least one evaluation module and at least one storage module according to a formation example suitable for the purpose. If the detection module is formed integrally with the sensor unit and / or as part of the sensor unit in a preferred manner, the photosensitive surface and / or photosensitive layer of the sensor unit will certainly be required by itself using adaptive light control. Can be. To be precise, for each own area, the required amount of light may be required. This is an immediate function, especially when the evaluation module of the control device is formed integrally with the evaluation unit and / or as part of the evaluation unit.

Conventional devices for personal identification using at least one fingerprint are incapable of performing the above, since the known devices are usually inflexible to adjust the light emitted over the entire area of the sensor unit without refraction. Because; In contrast, only adaptive light control relates to the optimum saturation within the evaluation module for all areas of the surface and / or layer of the sensor unit, taking into account the duration and / or the intensity of the required light, depending on the ambient light conditions. Can be supplied immediately.

According to a particularly preferred embodiment of the invention part of the adaptive light control (= ALR or ALC = "adaptive light control"), in other words "intelligent light control" means an optical image in the sensor unit and / or in the evaluation unit. It is possible to varyably form amplification of the electrical signal for different regions of.

The background of this particularly preferred embodiment is that the intensity distribution of the light controlled inside the front part of the finger and the resulting contrast are not uniform or constant over the entire width of the optical image, but rather in the middle of the optical image than in the edge region of the optical image. It is a fact that it is smaller in the area, and this is, among other things, at least one light source disposed on the side beside the finger support surface, and the light of the light source is directed in the opposite direction of the sensor unit, with the front part of the finger It is associated with the fact that it can be radiated in the direction of the side of the finger support surface, which is provided for supporting. This results in less light reaching into the central area covered by the front portion of the finger on the side of the finger support surface facing away from the direction of the sensor unit, rather than reaching into the side area, whereby the controlled light The intensity and (in direct proportional) of is weaker in the central region than in the lateral region.

Amplification of the electrical signal in the central region of the optical image, in this case, for example, by a factor of 2-3, is more than amplification of the electrical signal in the edge region of the optical image in accordance with a preferred embodiment of the present invention to eliminate the defect. Can be large. As described above, the electronic modulation using the variable amplification coefficient can be performed in every row of the optical image.

This makes it possible to compensate for the weaker light intensity and contrast that is controlled into the central area rather than into the side area in a smart way that is carried out electronically, while amplification is selectively spread over different areas of the optical image, with each scattered light The output signal, which is directly proportional to the intensity / contrast and the result of each amplification factor, is chosen so that the intensity can be approximately constant; Through such technical measures, the quality of the results obtainable using the device of the present invention can be decisively improved.

According to the practical formation of the device according to the invention, the device is designed for use in transition to a rest state. This is an advantage in the category of using the device of the device, for example in a mobile phone or in an automotive part such as a steering wheel, gearshift grip or door lock, because such an application category The electrical voltage required to operate the device at is usually obtained from the battery, using a solar collector, optionally supplemented, so that the savings associated with this are highly desirable by providing a stationary state of the device.

In this connection there may be provided at least one capacitive circuit suitably for the purpose and preferably integrated into the control device, by which the device of the invention is stopped after a predetermined non-use time. State (= so-called " sleep " mode), and with this circuit the device of the present invention "wakes up" again upon placing the front part of the finger on the finger support surface. In other words, it switches back to the ready state. As described above, in the device of the present invention for personal identification, a "weather" function as well as a "weather" function may be implemented.

As already stated above, in the scope of the present invention, for adaptive light control at least one light source fulfills an important function. In this respect, in most practical applications it is possible to be arranged symmetrically with one or more light sources, eg mutually, for the purpose of uniformly illuminating the front part of the finger and / or in the form of rings, in particular in particular here. It is contemplated that there are provided two light sources or in particular four light sources which can be evenly distributed and arranged around the finger support surface.

In particular in the practical formation of the device according to the invention each period and / or each intensity of the light pulses emitted from each light source is adapted to the ambient light conditions and is optionally adjustable; In other words, this means that the respective periods and / or respective intensities of the light pulses emitted from the respective light sources are mutually independent, and here they are controllable, in particular depending on a preset threshold. Therefore all light sources can be controlled independent of each other, and at the same time each period and / or each intensity is preferably calculated for each light source separately in the evaluation module.

In addition to controlling the light source and the number of light sources, another arrangement also plays a practical role in the present invention in accordance with the present invention. The light source is disposed on the side beside the finger support surface, and the light of the light source can be radiated to the side of the finger support surface provided to support the front part of the finger while being directed in the opposite direction of the sensor unit, Illumination of the front of the finger allows for reliable results.

At this point the light incidence on the front face of the finger is actually from the side, while at least a part of the light is transmitted into the interior of the front of the finger and scattered there, at the same time the scattering is actually in all directions, above all In the direction of the finger support surface of the optical fiber; The present invention is therefore clearly based on transmitted light, that is, the optical image of the fingerprint is treated as a transmitted light image.

Then, in the process of personal identification, the surface of the front face of the finger supporting the skin strips or the protrusions is placed on the finger support surface, while the skin strips or the protrusions are the input portion of the optical fiber of the finger support surface. So-called "through-light", so that any part of the so-called through-light scattered inside the front part of the finger in the areas of the optical fiber finger support surface closed by the skin strip or the protrusions as described above is finger It does not reach within the support surface or only minimally.

In the region of the groove between the skin strips or the projections, more scattered light reaches the optical fiber of the finger support surface, as a result of which preferably at least one photosensitive surface and / or at least one through the finger support surface. And a sensor unit comprising a photosensitive layer of the device, whereby a particularly sensitive device for the identification of the individual, depending on the fingerprint, in particular according to the area of the skin strip or protrusions and between the area of the skin strip or the protrusions Is provided.

The optical image of the fingerprint thus received passes through the optical fiber of the finger support surface and reaches within the sensor unit arranged behind the finger support surface, which is then analyzed and processed using an evaluation unit arranged in a preferred manner behind the sensor unit. In this regard, data and information obtained during analysis and processing may be collected and stored in at least one storage device arranged behind the sensor unit in a preferred manner.

In this association it is important that not only the device according to the invention can be fully identified, but also that the process of personal identification for the individual to be identified can be restored, since the individual is in a psychologically desirable manner. This is because they only need to be placed on the finger support surface. However, there is no need to insert the finger into the cavity or opening.

An optional practical feature of the device according to the invention is also the layout for life identification (so-called "life support"). In other words, an object that is also illuminated using the present invention based on the brightness difference between the areas of the skin strip or the protrusions and between the areas of the skin strip or the protrusions, approximately the front part of the finger It is possible to observe or investigate whether it is alive, that is to say whether the subject is for example perfused with blood and / or has a pulse. In this connection the device according to the invention may be designed to measure the oxygen saturation in the blood of the front of the finger, for example by comparing the results obtained for two different wavelengths.

In addition, using the present invention, for example, an individual may be identified as applied or authorized if only his actual pulse frequency does not deviate in the up / down direction by less than 10% of the stored pulse frequency. ; Therefore, pulse frequency is another criterion for personal identification.

As such, additional biological data relating to, for example, pulses, reduce the probability of error in the identification process, because the data makes it possible to distinguish the living finger of the individual to be identified from the fingerprint of the previously acquired finger of the individual. to be. Existing data on changes in the transparency of the front of the finger may measure the pulse of the individual to be identified, preferably in a computational manner within the evaluation unit, and use the obtained transparency curve similar to medical electrocardiogram (EKG). Allow.

It is also possible to measure an optical image using the device according to the invention, wherein the depth of focus of the image can be clearly and clearly discernible even if the individual glands of different positions are located within the front part of the finger. As high as possible, there is also the possibility of considering the glands in the scope of operation of the device and also for personal identification.

According to a preferred embodiment of the invention, the light source is arranged on the side of the finger support surface facing in the direction of the sensor unit. The above is a sufficient prerequisite for the point that the light from the light source can be directed in the direction of the side of the finger support surface provided for supporting the front part of the finger while being directed in the opposite direction of the sensor unit. In other words, the front part of the finger of the individual to be identified is floodlighted from the downward side of the side.

In addition, the light source may be disposed to be spaced apart from the sensor unit to the side to suit the purpose. Such structural separation of the light source and the sensor unit should only be recommended in that the point of arrival of the light source directly from the light source into the sensor unit should be avoided in order to achieve the orderly operation of the device. Rather it is only previously scattered inside the front part of the finger, so that the light having the information on the skin strip or protrusions, in other words on the fingerprint, preferably operates on the basis of semiconductors, in particular on silicon. You must reach within the unit.

According to a practical formation of the device for personal identification according to the invention, the light from the light source is directed laterally from the sensor unit, radiating laterally on the side of the finger support surface provided for supporting the front part of the finger. It is possible. This formation is particularly contemplated when the light source is arranged next to or approximately on the side of the finger support surface facing in the opposite direction from the sensor unit in a preferred form; The light sources may also be laid down so to speak in the above formation, and light is emitted “in plane” on the front of the finger.

Optionally, the light source may be formed as a pulsed light source. The pulsed light source is designed for the divergence of pulsed light, so that the device according to the invention can be operated, for example, completely by battery, as a result of pulsed light which can be supplied accurately. In any case, a significant reduction in the current required to operate the device according to the invention is achievable, since ambient light can be used and additionally the necessary light can be supplied correctly using adaptive light control. . The impulse duration of the light pulses emitted at this point is preferably between about zero milliseconds and about 90 milliseconds, in order of magnitude.

Correspondingly, the device according to the invention may comprise at least one pulse generating unit for controlling the light source, while at the same time the pulse generating unit is suitable for the purpose of the light source and at least one sensor unit. It is arrange | positioned between control elements.

At least one display device is provided for indicating different modes of operation of the device in accordance with a preferred embodiment of the present invention for signaling and indicating to each individual operating state of the device to be identified. In this case the display device comprises at least one color or several colors of indicators, suitably for the purpose, which indicators signal and indicate different modes of operation of the apparatus (eg green light: “The device is ready for personal identification. Status "or" Device has identified individuals in sequence "; Red light:" Device is not ready for identification "or" Device has not identified individuals in sequence ").

In connection with the above, it is recommended to integrate the display device into the light source and / or to form the display device and the light source in one piece, in particular in a smart and / or compact manner.

For example, in order to enable individuals who are lacking in color to understand the respective operating modes of the device, the display device may also be configured to at least one blinking and / or pulsating different operating modes of the device according to the preferred alternative or supplementary configuration. It may be indicated by signaling through an light signal.

In particular, at least one optical system is arranged at the rear of the light source according to the formation of the invention. The optical system, on the one hand, performs a reliable protection function, that is, the optical system prevents the individual to be identified using his fingerprint from touching the light source which is sensitive and fragile when placing the front face of the finger.

In a particularly preferred manner, however, the optical system deflects the light emitted from the light source on the side of the finger support surface facing away from the sensor unit, and / or the light emitted from the light source is directed away from the sensor unit. It is designed to distribute evenly and / or spread on the side of the finger support surface.

Doing so ensures uniform illumination of the front face of the finger, thereby producing an informative optical image of the fingerprint obtained from the front face of the finger. This is important for ensuring the functioning of the device according to the invention.

In a preferred method the optical system is at least one filter, at least one lens, at least one prism, at least one optical fiber light guide, at least one light guide member and / or at least one It is formed as a mirror, and at the same time the above-mentioned optical members are used alone or in combination depending on, for example, the available space or the required illuminance.

In addition to meeting the above-mentioned protective functions, it is proposed to select plastic as the material of the optical system in terms of light distribution. Plastics are inexpensive, rugged materials, and certainly have optical properties, especially in transparency designs.

Where it may also be suitable for the purpose to fulfill the above-mentioned protective functions, at least one material, in particular infrared and / or visible light, through which at least the side of the optical system facing away from the light source passes the light of the light source When coated with the material to pass through. The optical system, which is frequently sensitive, is thereby protected from damage, such as scratching and / or contamination by damage, and at the same time, the cleaning of the optical system is also facilitated by coating with a light transmissive material.

In particular, according to an embodiment of the device according to the invention, at least one finger guide (preferably ergonomically shaped) is provided on the side of the finger support surface provided for supporting the front part of the finger while facing away from the sensor unit. finger guides are provided. For the user of the device, for example the individual to be identified, by means of the finger guide, which may be formed, for example, in the form of a "finger shoe", the operation of the device is essentially used from a psychological point of view and from a practical point of view. This becomes easy. Because the individual to be identified is instinctively positioned due to the placement of the finger guides, at which and at what places the front face of the finger should be placed on the side of the finger support surface facing away from the sensor unit, so as to detect the fingerprint, Because I grasp.

If the device according to the invention is to be formed in a particularly skilled manner, it is recommended to form the optical system as a finger guide. The advantage of the finger guide in this way, that is, first of all ensuring the optimal positioning of the front part of the finger for the detection of a fingerprint, is the advantage of the optics in a way that is suitable for the purpose, above all the deflection component for the generated light. Function as a function and guarantees a clean and uniform illumination of the front face of the finger to be illuminated.

Of particular note in this association is that adaptive light control allows for easy control and uniform transitions to be achieved for different regions of the overall image configurable in a particularly desirable manner. Thus, the interaction of finger guides and adaptive light control, optionally implemented within the optics, ensures a uniform distribution of light to the object to be illuminated when the contrast is uniform.

In view of coating the optical system with a light transmissive material, the above-mentioned conditions also apply to the preferred embodiment of the present invention, in which the side of the finger support surface facing away from the sensor unit is at least the light of the light source. It is coated with at least one material which passes, in particular with a transparent material for infrared and / or visible light. In this respect, the coating of the finger support surface is practically important to the present invention, provided that a clean finger support surface that is intact, that is, above all scratch-free, is essential for the orderly function of the device for personal identification. Can have.

In the case of the optical system as well as in the case of the finger support surface, the transmissive material for the light of the light source is varnished according to a preferred embodiment.

It may be advantageous in the context of the present invention when the light source is a light emitting diode (LED). At the same time the advantage of the light emitting diodes is that they are also used in the devices according to the invention, which in particular are very small and consequently require little space with a series of miniaturizations. Further advantages include the light weight of the light emitting diodes, the robust shape, low operating voltage and high lifetime.

According to a preferred embodiment of the present invention, the light source emits infrared light, while at the same time the infrared light can comprise a wavelength of, for example, approximately 900 nanometers. In a form suitable for the purpose, a light source capable of emitting infrared rays of two different wavelengths may also be used, for example, in the case of an output of approximately 0.1 milliwatts to approximately 5 watts, in particular cases, to avoid heating the device to extremely high temperatures. It should contain an output from approximately 2 milliwatts to approximately 100 milliwatts.

The sensor unit is arranged on at least one support unit in a manner suitable for the purpose in order to give a reliable stability to the device for personal identification of the present invention. The support unit may again be disposed on at least one printed circuit board unit.

In order to ensure that light with an optical image of the fingerprint originating from the front of the finger passes through the finger support surface in order to be transmitted to the sensor unit, the optical fibers in the finger support surface are actually fingers according to the practical formation of the invention. It is oriented perpendicular to the incident and / or radial plane of the support surface.

For this purpose, the optical fibers in the finger support surface are actually arranged parallel to each other according to the preferred embodiment of the present invention. As an alternative in this regard, the optical fibers in the finger support surface may have bidirectional directions which are arranged at substantially some angle to each other in the practical formation of the invention. In this case, in a preferred embodiment, the optical fibers in the finger supporting surface are arranged in layers, while the optical fibers are substantially parallel to each other in one layer and the optical fibers of the layers adjacent to each other have a certain angle to each other. Are arranged.

In the preferred embodiment described above, the optical fibers of the finger support surface disposed in one direction angled with respect to the other direction are suitably provided for transmitting light on the side of the finger support surface facing away from the sensor unit. On the contrary, the optical fibers of the finger support surface disposed in the other direction are provided for transmitting the optical image of the fingerprint to the sensor unit suitably for the purpose.

Of particular note in connection with the above, the arrangement of the optics by means of the preferred embodiment described above using two preferred directions for the optical fibers is such that uniform illumination of the front part of the finger is angled relative to the other direction. The contents are out of date as long as they are guaranteed by the optical fibers of the finger supporting surface disposed in one direction.

In particular according to an embodiment of the device for personal identification according to the invention at least a part of the optical fibers in the finger support surface is enclosed at least in part in the form of a coating and / or in the form of a wrapping by a (light) absorbing material. Are stacked. Thereby the light incident from the outside through the sides of the optical fibers and / or the light incident from the adjacent optical fibers is absorbed, so that light entering all the optical fibers into the finger support surface in a given area passes through the finger support surface. It continues to be directed to its radial plane. In this way a change in the light sample obtained at the incident surface of the finger support surface is avoided in an acceptable manner.

In an alternative or supplementary manner in connection with the above, likewise in particular by means of a material in which at least one part of the optical fibers in the finger-supporting surface is fractionally (light) reflective, in particular according to the formation of a device for personal identification according to the invention. It is enclosed in the form of a coating and / or in the form of a wrapping. The coating re-reflects light in each optical fiber in a preferred manner again into the interior of the same optical fiber at the wall of the optical fiber. The transmission of the optical image through the finger support surface to the sensor unit is therefore only provided that all the optical fiber continues to direct light entering the finger support surface through the finger support surface to its radiation plane in a defined area. It becomes good. In this way a change in the light sample obtained at the incident surface of the finger support surface is avoided in an acceptable manner.

Regardless of the point of departure from the optical system, the finger support surface is provided with an expansion that extends into the area beyond the light source, thereby covering the light source and protecting it from hand interference.

The sensor unit should only touch light which naturally has information relating to the optical image of the fingerprint, ie it is scattered by the front of the finger, so it is recommended that at least one light non-transmissive barrier layer is provided inside the finger support surface. Is provided. This is because, by using the light non-transmissive blocking layer, the light emitted from the light source is prevented from reaching the sensor unit directly without being scattered at the front part of the finger. In this respect, the blocking layer can be realized in the form of a closed optical fiber, for example.

At least one light impermeable barrier layer that can be provided between the light source and the sensor unit to serve the same purpose as the barrier layer in the finger support surface. In this connection the material of the blocking layer which does not transmit light of the light source can be, for example, a varnish.

If the device for personal identification is to be formed in the practical manner of the present invention, at least one filter is preferably provided that is formed as a linear filter, which absorbs disturbances and excess ambient light and consequently It is for reliably excluding supersaturation of a sensor unit.

In other words, the adaptive light control means that the sensor unit exhibits its optimum efficiency when it is surely "saturated" by, for example, normal day light. At the same time the saturation can be prevented in a way that is suitable for the purpose by the placement of the filter directly, because the device for personal identification by the filter can also be operated when the ambient light is approximately 3,00 Lux or more. At the same time, the maximum limit must be present when the ambient light illuminance is approximately 40,000 Lux. In this regard the filter comprises an absorption of approximately 99% in a manner suitable for the purpose. In other words, the light absorbing filter does not provide any efficient protection against saturation, which is disclosed from the "dark room" (approximately in German publication DE 44 04 918 A1, and also cannot accept the function of the "dark room"). In contrast to a filter with ").

The placement of filters inside the device for personal identification is determined by the configuration, dimensioning and purpose of use of the device. However, as suitable for the purpose,

Placing a filter between the finger support surface and the sensor unit; And / or

Arranging the filter on the side of the finger support surface facing away from the sensor unit; And / or

Arranging the filter on the side of the finger support surface facing in the direction of the sensor unit; And / or

To provide a filter inside the finger support surface.

According to a particularly preferred embodiment of the invention part of the adaptive light control (= ALR or ALC = "adaptive light control"), that is, "intelligent light control", changes the absorbance of the filter over different areas of the optical image. It can be formed possibly.

In the background of this particularly preferred embodiment, the intensity distribution of the light scattered inside the front part of the finger and consequently the contrast is not uniform or constant over the entire width of the optical image, but rather optical in the edge region of the optical image. It becomes smaller within the center area of the image. This is, among other things, at least one light source disposed on the side beside the finger support surface, and the light of the light source is directed in the opposite direction from the sensor unit, with the side of the finger support surface provided for supporting the front part of the finger. Is associated with points that can be radiated onto the phase. The result is that less light reaches into the areas of the side which are covered by the front part of the finger on the side of the finger support surface facing away from the sensor unit rather than into the areas of the side, whereby The intensity and contrast (in direct proportion to this) of light scattered into the central region becomes weaker.

According to a preferred embodiment of the present invention to eliminate such defects, the absorption of the filter in the edge regions of the optical image is greater than the absorption of the filter in the central regions of the optical image, and in this respect for example the coefficient of About 2 to 3 and / or about 6 decibels to about 10 decibels.

So the problem is the practical selection technical measures of the invention, in which case the density of the optical filter over different regions of the optical image is less than the density of the filter in the central region of the optical image, Is formed to a greater degree, and in this respect, for example, about 2 to 3 coefficients and / or about 6 decibels to about 10 decibels.

This can be compensated for in a smart way implemented using optical modulation, in that the intensity and contrast of the light scattered in the central region is weaker than in the lateral region. At the same time, the absorptivity may be chosen over different regions of the optical image, such that the output signal is approximately constant, which is directly proportional to the ratio of each scattered light intensity / contrast and each absorptivity; Through these technical measures, the quality of the results obtainable with the device can be decisively improved.

In this connection, the above-mentioned selection of technical modulation of optical modulation also shows that, compared to the above-mentioned selection of electronic modulation using electronic amplification factor, amplification of disturbances, such as electronic noise, is particularly effective in optical modulation. Has the advantage of being excluded within the central area; Rather, such undesirable disturbances can be further reduced by optical modulation.

In order to enable detection by the sensor unit of a direct iso-optical signal which is not modulated by disturbing action, an embodiment in which the sensor unit is directly adjacent the finger support surface and / or the sensor unit is installed on the radiation surface of the finger support surface is preferred. Do.

The sensor unit may comprise at least one structural member based on CMOS technology or at least one circuit based on CMOS technology in a manner suitable for the purpose (CMOS = complementary MOS).

In the alternative replaced or supplemented in this regard, at least one charge coupled structural member or at least one charge coupled circuit (CCD = charge coupled device) may be provided. In this case it may be at least one single region CCD, which in particular acts as a photosensitive unit and does not contain any regions which are protected from isolated light.

The expert will know that in this connection it is desirable to have a semiconductor surface that corresponds to only half of the surface required by a conventional method in a CCD sensor unit. Because in the case of CCD sensor units the acquired image can be read directly in the dark phase, and as in the case of conventional sensor units, it takes up almost 50% of the sensor surface and finally the read-out. This is because it does not have to be transferred into the non-photosensitive region where out) takes place.

In this respect, the image formation and the readout of the charge are integrated within the photosensitive unit, and at the same time the process of the image formation and the charge readout are separated into two area CCDs in time, but they are separated from each other in space. It doesn't work. In this respect, single-area CCDs are characterized, above all, by being clearly simpler and less expensive to manufacture than two-area CCDs, since for single-area CCDs the quantity of components is actually the same in the dimensions of the photosensitive unit. This is because the case is only about half that of the two region CCDs.

The only consideration in this association is that single-area CCDs cannot be used to illuminate objects to be illuminated continuously or invariably, because they occur during simultaneous image formation and readout. This is because undesired mixing of images may occur.

For the same reason as described above, the light source may be formed as a pulsed light source designed for the purpose of emitting pulsed light, as already performed previously. Correspondingly, the device according to the invention may comprise at least one pulse generating unit for controlling the light source. At the same time, the pulse generating unit is disposed between the light source and the control member for at least one sensor unit, suitably for the purpose.

Experts believe that in this association, instability and nonuniformity are also significantly reduced in the optical image of the fingerprint obtained by using light pulses to illuminate the front of the finger and in the resulting electrical signal. You will find that fact is particularly desirable.

This effect is a direct result of the light pulses for a short period of time, preferably approximately one (1) millisecond period, and at the same time ignores the effect of blood flow in the front of the finger to be viewed on the quality of the optical image of the fingerprint obtained. Become a variable.

In addition, by reducing the image formation time, the influence of ambient light conditions on the high relief optical image is critically reduced.

As a result, by using the device for personal identification according to the present invention, instead of blurring optical images that occur when using illumination time corresponding to invariant illumination and image delay time, The possibility of acquiring distinct, sharp optical images of the fingerprint contained at the time when the entire information is determined is provided.

The improvement of the quality of the images obtained as above allows to reduce the error rate and probability in the individual identification in a significant way. Further, from now on, the continuous processing of the images results in the acquisition of additional biological data of the individual to be identified, such as the characteristics of the pulse, which increases the information content of the images under the fingerprinting method, thereby continuing to improve the stability of the personal identification.

The use of a pulsed light source not only improves image quality as described above, but also allows the use of at least one camera with single area CCDs as the photosensitive unit. The use of single area CCDs makes it possible to obtain high quality images of larger surfaces. This magnification of the surface, along with the improvement of the stability of the optical images, continues to reduce the probability of error in personal identification.

In this regard, the manufacture of single-area CCDs with one diagonal photosensitive region and optical fiber inputs, for example from about 16 millimeters to about 24 millimeters, is a technically rather complex problem, whereby a relatively simple and inexpensive personal identification device is thereby provided. It can be prepared. In addition, in the devices using single area CCDs according to the present invention, information distortion occurs lower than in devices using other types of charge transfer.

It is not possible to use single area CCDs in devices operating with continuous or constant illumination, because continuous or constant light is incident on the CCDs during the readout phase as well as during the image forming step. This may result in a mixture of charges that would render it impossible to obtain a clear optical image of the high relief of the front of the finger.

Further embodiments, features and advantages of the invention are described in the following according to FIGS. 1 to 4C in the drawings, through which three embodiments of a device for personal identification according to the invention by way of example are shown. It is.

1 shows a first embodiment of a device for personal identification according to the invention;

2 shows a second embodiment of a device for personal identification according to the invention;

3A shows a third embodiment of a device for personal identification according to the present invention;

3B is a cutaway view of the finger support surface of the device for personal identification according to FIG. 3A;

3C is a cutaway view of the finger support surface according to FIG. 3B in a partial front view;

4A is a diagram in which contrast of light scattered inside the front portion of a finger is schematically depicted over the width of the optical image;

4B is a diagram in which the amplification of a selected electrical signal in the device for personal identification of FIG. 1 is schematically depicted over the width of the optical image;

4C is a diagram in which the amount of absorption selected in the device for personal identification of FIG. 2 is schematically shown over the width of the optical image.

1 to 4C, the same or similar components or features of the present invention are denoted by the same reference numerals.

Three embodiments of an apparatus for identifying an individual using at least one fingerprint, shown in FIGS. 1 through 3A, serve to accept and process fingerprints, and within all areas where personal identification is required. Can be used. By way of example, in the above-mentioned relations, the domains include computer technology, permitting system, crime prevention science, medicine, general protection system, and banking / finance.

In this respect, three embodiments of the device for personal identification using one fingerprint shown in FIGS. 1 to 3A are possible on the one hand, but with the illumination of the front of the finger, which produces a sufficient and reliable result, but the other On the other hand, it is not only completely identifiable by the device itself for personal identification, but also characterized in that the personal identification process for the individual to be identified is reproducible and easy.

In this regard, the three embodiments of the personal identification device using one fingerprint shown in Figs. 1 to 3A are four for illuminating the front part of the finger, which are each arranged symmetrically with respect to the sensor unit 40. One optical fiber finger support for receiving an optical image of a fingerprint and a light source 10 (only two of the four light sources 10 are shown in FIGS. 1 to 3A for general purposes) It includes the face 30.

The optical image of the fingerprint is transmitted to the sensor unit 40 through the finger support surface 30, and the optical image of the fingerprint is converted into an electrical signal in the sensor unit. The sensor unit 40 is disposed on the support unit 50, and the support unit is again disposed on the printed circuit board unit 60.

As a result, the light sources 10 are disposed on the side of the finger support surface 30, and the light of the light sources 10 is directed from the sensor unit 40 in the opposite direction to support the front part of the finger. Is radiated on the side of the finger support surface 30 provided for the purpose.

In this respect the light incidence on the front face of the finger is actually from the side, at the same time at least a part of the light is transmitted and scattered therein into the front of the finger, at the same time the scattering is actually in all directions, above all the fingers of the optical fiber In the direction of the support surface 30; Thus the invention shown according to FIGS. 1 to 4C is reliably based on transmitted light technology. In other words, the optical image of the fingerprint is treated as a transmission image.

Then, in the process of personal identification, the surfaces of the front face of the finger supporting the skin strip or the protrusions are placed on the finger support surface 30, and the skin strip or the protrusions are formed on the finger support surface 30 by area. Scattering inside the front part of the finger in the areas of the optical fiber finger support surface 30 that seal the input of the optical fibers 310 (compare FIG. 3B with FIG. 3C), thereby being sealed by the skin strip or protrusions. None of the so-called so-called penetrating light reaches within the finger support surface 30 or only slightly reaches it.

In contrast, in the groove region between the skin strip or the projection lines, more scattered light reaches the optical fibers 310 of the finger support surface 30, and as a result, passes through the finger support surface 30 and passes through the sensor unit 40. Leads to Thereby a particularly sensitive mechanism for identifying an individual is provided, depending on the fingerprint, in particular according to the area of the skin strip or the projections, and according to the area between the skin strip or the projections.

The optical fibers 310 in the finger support surface 30 are covered with a (light) reflective material in the form of a coating, the coating having the same light in each of the optical fibers 310 again at the wall of the optical fibers 310. Re-reflects into the optical fibers 30. In so doing, the transmission of the optical image through the finger support surface 30 to the sensor unit 40 is such that all of the optical fibers 310 only enter light into the finger support surface 30 in the designated area. It is satisfactory only in that it continuously guides through 30) to the radial surface of the support surface. In this way a change in the light sample obtained at the incident surface of the finger support surface 30 is avoided.

Thus, the optical image of the fingerprint received as described above passes through the optical fibers 310 of the finger support surface 30 to reach the sensor unit 40 disposed behind the finger support surface 30, and then the sensor unit. It is analyzed and processed using an evaluation unit disposed behind 40.

In this respect the object, also the front part of the finger, which is also illuminated using the invention shown in FIGS. 1 to 4C based on the difference in brightness between the areas of the skin strip or the projections and the areas between the skin strip or the projections It is still possible to observe or investigate whether there is, in other words, whether blood flows through the subject, and / or whether it has a pulse (so-called "life sustaining").

Therefore, using the invention shown in Figs. 1 to 4C, if an individual's pulse frequency deviates by about 10% or less above / below the stored pulse frequency, the individual may be authorized or identified as authorized; Therefore, the pulse frequency is one additional criterion for personal identification.

Such additional biological data relating to the pulse reduces the probability of error in the identification process, since the data makes it possible to distinguish the living finger of the individual to be identified from the fingerprint of the previously acquired finger. Existing data on the change in the projection of the finger front part allow the calculation of the pulse of the individual to be identified by calculation, and similarly use the obtained projection curve to the electrocardiogram (EKG) for medical use.

Optical images can also be measured using the device according to FIGS. 1 to 3A. The depth of focus of the image is as high as it is clearly and clearly recognizable to the differently placed individual glands present in the front of the finger, thereby operating the device shown according to FIGS. 1 to 3A. In the category, there is also the possibility of considering the glands for personal identification.

In this respect the device according to the invention shown by way of example in FIGS. 1 to 3A is completely identifiable, and the process of personal identification is reproducible and easy for the individual to be identified. This is because the individual only needs to place his finger front face on the finger support surface 30 in a psychologically good manner. However, it is not necessary to insert the finger into the cavity or opening.

The invention shown in accordance with the three embodiments shown in FIGS. 1 to 3A shows that the duration and intensity of the light pulses emitted by the light sources 10 are adjustable depending on the ambient light conditions, that is, Adaptive light control (= ALR or ALC = "adaptive light control"), thereby providing a kind of "intelligent light control". Through the adaptive light control, the deficiencies of changing ambient steel conditions such as approximately altered room lighting or altered solar radiation can be balanced, while embodiments of the three devices shown in FIGS. An algorithm that controls the device is adapted to the respective light conditions.

In this regard, in the case of the three devices for personal identification according to the examples shown in FIGS. 1 to 3A, there is provided one control device 40 and 70 for controlling the duration and intensity of the light pulse. A continuous or temporary measuring method can be executed using the control devices 40 and 70 formed as a digital signal processing unit (DSP = digital signal processor) including a microcontroller, and permanently using the measuring method. Good image quality is measurable and, if necessary, optimal saturation, adjusted for contrast and depth of focus, can be achieved using short pulses of light, while short pulses of light It is supplied with exactly the amount of light actually required in intensity.

The control device 40, 70 comprises one detection module 40 for detecting ambient light conditions, while at the same time the detection module 940 is a sensor unit in three embodiments in FIGS. 1 to 3A. It is formed integrally with the 40.

At the rear of the detection module 40, one evaluation module 70a is always arranged to determine the duration and intensity of the light pulses by adapting to the ambient light conditions detected from the detection module 40. The evaluation module 70a is formed integrally with the evaluation unit 70a, which is arranged behind the sensor unit 40 and subsequently enters detailed information.

Similarly, one storage module 70 for storing the threshold value determined for controlling the duration and intensity of the light pulse is always arranged behind the detection module 40, and at the same time, the storage module 70b is a sensor unit ( 40) It is formed integrally with at least one storage unit 70b, which is disposed at the rear side and is then inputted with detailed information.

If the detection module 40 has detected respective ambient light conditions, the conditions are evaluated and analyzed in the evaluation module 70a and at the same time in the evaluation module 70a the preset thresholds stored in the storage module 70b. Comparison is made.

Depending on the result of the comparison, the control device 40, 70, in this case, in particular in this case, the control device 40, 70 reacts to the light sources 10 connected to the evaluation module 70a and at the same time the light sources ( The duration and intensity of the light pulse measured by 10) is adapted to the measured ambient light conditions.

This allows the light pulse to generate the incident light emission required for all types of ambient light (e.g. strong, weak, calm, incandescent, moonlight, artificial light, ...) not only in its period but also in its intensity. In use, it can be formed dynamically and adaptively, thereby enabling to obtain fingerprint images of high contrast and depth of focus.

In particular, with adaptive light control, illuminances from zero Lux to approximately 40,000 Lux can be achieved, while at the same time the maximum illuminance is approximately direct solar radiation. The results achievable using the adaptive light control described above have an elevation of contrast and depth of focus by approximately 80% compared to conventional lighting systems using invariant light, and at the same time specified according to an example according to FIGS. 1 to 3A. This type of light control is free to use when the lighting conditions are changed, providing the required amount of light in less than 100 milliseconds of time, thereby maintaining an image quality that remains nearly uniform for all conceivable light conditions. Has the advantage of being obtained.

Thus, the decisive advantage of the device shown by way of example in accordance with the three embodiments in FIGS. 1 to 3A is obtained in the context of "intelligent control". The intelligent control explicitly adjusts the amount of light emitted by itself as needed and freely utilizes the calculated amount of light in the periphery of the object to be illuminated, i.e. around the front of the finger, separately for all areas, thereby calculating it. In the device for personal identification according to Figs. 1 to 3A having a probability limited to safety, the over or under exposure is excluded.

The invention shown in FIGS. 1 to 4C also allows for uniform illumination of the object, approximately the front of the finger, and, more precisely, may include some strong light conductivity or rather strong reflection capability throughout. This allows for uniform illumination regardless of the thickness of the object present and whether the object is illuminated by unnecessary light at the front, side and / or back.

As a result, at what angle and from which position the light is emitted to the object to be illuminated does not play an important role; Only additionally necessary light duration and intensity should be controlled individually for each area. Finally, as an advantage of the adaptive light control of the present invention, the finger image can be measured with the contrast and the depth of focus acquired over the entire range without actually changing the illumination time.

As stated above, the control devices 40, 70 provided in FIGS. 1 to 3A for implementing adaptive light control are one detection module 40, one evaluation module 70a and one storage module. 70b is included. If the detection module 40 is integrally formed with the sensor unit 40 (compare FIG. 1 to FIG. 3A), the photosensitive surface of the sensor unit 40 is clearly itself by using adaptive light control. It is possible to request the required amount of light (in detail, for all areas of its own), which functions in a preferred way, since the evaluation module 70a of the control device 40, 70 is integrated with the evaluation unit 70a. Because it is formed.

The adaptive light control thus calculates the amount of light required for all areas of the surface of the sensor unit 40 in accordance with the ambient light conditions, with regard to the optimal saturation in the evaluation module 70a, taking into account the duration and intensity, And it can be supplied reliably.

In connection with the operation of the adaptive light control, in the three embodiments of the invention shown in Figs. 1 to 3A, the disturbances and the excess ambient light are absorbed and, consequently, the supersaturation of the sensor unit 40 It is of practical importance that one filter 90 is provided which is always formed as a linear filter so that it can be excluded.

In other words, the above-mentioned point is that the adaptive light control is in the range of FIGS. 1 to 3A if the sensor unit 40 is not clearly "saturated" by itself, for example by normal daylight. It means that they will work their best. At the same time the supersaturation state is immediately prevented by the placement of the filter 90, since the device for personal identification illustrated by the filter 90 in accordance with FIGS. 1 to 3A also has an illuminance of ambient light of approximately 3,000 Lux. Can also work, but at the same time the actual maximum limit should be present when the ambient light is approximately 40,000 Lux. In this regard the filter 90 comprises approximately 99% absorption, ie the light absorbing filter 90 acts as a result in the "darkroom".

The placement of the filter 90 in each personal identification device is determined by the configuration, dimensioning and purpose of use of the device. therefore

For the first embodiment (compare FIG. 1), the filter 90 is arranged between the finger support surface 30 and the sensor unit 40;

In the case of the second embodiment (compare FIG. 2), the filter 90 is on the side of the finger support surface 30 facing in the direction of the sensor unit 40 and in this respect the interior of the finger support surface 30. Is placed in; And

In the case of the third embodiment (compare FIG. 3), the filter 90 is arranged on the side of the finger support surface 30 which faces away from the sensor unit 40.

As already stated above, the light sources 10 (compare FIG. 1 to FIG. 3A) fulfill an important function in the scope of the present invention in the case of adaptive light control. Consideration in this regard is that in the three embodiments specified according to FIGS. 1 to 3A for the purpose of uniform illumination of the front of the finger, in the form of a ring, while being arranged symmetrically with each other, in this case In particular, one or more light sources are provided that are actually evenly distributed and arranged around the finger support surface 30 (four light sources in all three embodiments from FIGS. 1 to 3A).

Each period and each intensity of the light pulses emitted from the respective light sources 10 can be selectively controlled to adapt to the ambient light conditions in three embodiments from FIGS. 1 to 3A; In other words, this means that each period and each intensity of the light pulses emitted from the respective light sources 10 are independent of each other, in this case being controlled in particular in dependence upon a preset threshold. Thus all light sources 10 can be controlled independent of each other; At the same time each period and each intensity are respectively calculated in the evaluation module 70a for all light sources 10.

The evaluation unit 70a and the storage unit 70b have already been mentioned above. The units,

In the case of the first embodiment (compare FIG. 1), it is provided as a control unit 70 in a structurally integrated manner, which, together with the light sources 10, supports the support unit 50 and the printed circuit board unit 60. It is connected with the sensor unit 40 through;

In the case of the second embodiment (compare FIG. 2), it is structurally separated and provided as a control device 70, which is provided via a printed circuit board unit 60 with light sources 10 and a support unit ( 50) and the printed circuit board unit 60 are connected to the sensor unit 40; And

In the case of the third embodiment (compare FIG. 3), it is structurally and functionally integrated into the printed circuit board unit 60.

As a result, as shown in FIGS. 1 to 3A, the evaluation unit 70a is disposed behind the sensor unit 40, and supports the finger through the optical fibers 310 of the finger support surface 30. It has a function of analyzing and processing the optical image of the received fingerprint that reaches within the sensor unit 40 disposed behind the face 30. In this regard, data and information obtained during analysis and processing can be stored vertically and in the storage unit 70b which is similarly disposed behind the sensor unit 40.

The data and information, in particular the fingerprint data and fingerprint information of the individual to be identified, are also stored in the storage unit 70b and at the same time the data calculated in the evaluation unit 70a from the optical image of the actual fingerprint in the identification process. And information related to data and information stored in the storage unit 70b and can be compared and adjusted.

If a match is found to be matched in the comparison, the individual using the device is identified as being identified, authorized or authenticated, thereby allowing access, for example. On the other hand, if there is a mismatch, the individual using the device is considered unidentified and is not authorized or certified, thereby denying access, for example.

In the first and second embodiments of the present invention shown in FIGS. 1 and 2, one optical system 20 made of plastic, which is always formed as a lens, is arranged behind the light sources 10. The optical system 20 performs a reliable protection function on the one hand, that is, by the optical system 20, light sources that are sensitive and easily damaged when an individual to be identified using his fingerprint puts the front part of a finger. The point of contact with (10) is prevented.

In particular, however, the optical system 20 deflects the light emitted from the light sources 10 to the side of the finger support surface 30 facing away from the sensor unit 40 and radiates from the light sources 10. It is designed to diffuse and distribute the light to the side of the finger support surface 30 in the opposite direction from the sensor unit 40.

This ensures uniform illumination of the front face of the finger, thereby producing an optical image of the informative fingerprint resulting from the front of the finger. This is important for ensuring the functioning of the device according to the invention.

The first and second embodiments of the invention shown in FIGS. 1 and 2 are characterized in that in the above connection, in particular, the optical system 20 is formed as a ergonomically shaped finger guide. It is thus formed in the form of a finger receiver on the side of the finger support surface 30 which is provided to support the finger front part while facing away from the sensor unit 40 and allows the user of the device, for example an individual to be identified, to One finger guide is provided that facilitates the use essentially from a psychological point of view as well as from a practical point of view. Because the individual to be identified should place the finger guide, the finger front part must be placed at a certain position and at a certain position so that the fingerprint can be detected on the side of the finger supporting surface 30 facing away from the sensor unit 40. It is because it grasps instinctively (in comparison with FIG. 1 and FIG. 2).

The advantages of the finger guides in the first and second embodiments of the invention shown in FIGS. 1 and 2 in this manner are, above all, that ensure optimal positioning of the front of the finger so that the fingerprint can be detected. This is in conjunction with the advantages of the optical system 20, ie functioning as a deflection component for light generated above all, as well as ensuring clean and uniform illumination of the front of the finger to be illuminated.

It is particularly important to note in this connection that a uniform transition can be achieved while being easy to control for different areas of the overall image that can be constructed by adaptive light control. Thus, by the interaction of the finger guide and the adaptive light control implemented in the optical system 20 (compare FIG. 1 and FIG. 2), uniform light distribution is ensured for the object to be illuminated when the contrast is as maximum as possible.

In the case of the first embodiment of the invention shown in FIG. 1, the side of the optical system 20 facing away from the light sources 10 is one transmissive material 80 to the light of the light sources 10, in other words, It is coated with a transparent material 80 for infrared light. As a result, the optical system 20 which reacts frequently and sensitively is prevented from damage, such as scratching and / or contamination by damage, and at the same time, the coating of the light transmitting material with the light transmitting material also facilitates the cleaning of the optical system 20.

In the same way, in the first embodiment of the present invention shown in FIG. 1, the side of the finger support surface 30 facing away from the sensor unit 40 is a transparent material for the light of the light sources 10. In other words, it is coated with a transparent material 10 for infrared rays. In this regard, the coating of the finger support surface 30 as described above, the clean finger support surface 30, which is not damaged, that is, not scratched, functions in accordance with the order of the device for personal identification shown in FIG. Intrinsic importance, but only for the purpose.

Not only in the case of the optical system 20, but also in the case of the finger support surface 30, the transparent material 80 for the light of the light sources 10 becomes varnish.

It should also be mentioned in particular when considering the first embodiment of the invention shown in FIG. 1 that part of the adaptive light control (= ALR or ALC = "adaptive light control"), ie "intelligent light control" Within unit 40 or evaluation unit 70a it is possible to varyably form the amplification of the electrical signal over different areas x of the optical image (compare FIGS. 4A and 4B).

In the background above, the intensity distribution of light scattered inside the front of the finger and the resulting contrast are not uniform or constant over the entire width x of the optical image, but rather the center of the optical image than in the edge regions of the optical image. The fact that it is smaller within the regions (compare the chart in FIG. 4A where the contrast of light scattered inside the front of the finger is schematically shown over the width x of the optical image); This point is above all, the light sources 10 are arranged on the side of the finger support surface 30, and the light emitted from the light sources 10 is directed in the opposite direction from the sensor unit 40, the front of the finger. It is associated with the radiation on the side of the finger support surface 30 which is provided for the support of the part. This results in less light reaching the central areas covered by the finger fronts on the side of the finger support surface 30 facing away from the sensor unit 40 than the areas of the side surfaces, whereby scattered light The intensity and (in this regard directly proportional) the contrast is weaker in the central regions than in the lateral regions.

For the first embodiment of the invention, which is specified according to FIG. 1 to eliminate the deficiency, the amplification of the electrical signal in the central regions of the optical image is approximately greater than the amplification of the electrical signal in the edge regions of the optical image. Coefficients are made as large as 2 to 3 (compare the diagram in FIG. 4B where the amplification of the selected electrical signal in the device for personal identification of FIG. 1 is schematically shown over the width x of the optical image).

In this case, such electronic modulation using a variable amplification coefficient is performed in every column of the optical image.

Thereby, in an electronically implemented manner, the fact that the intensity and contrast of the scattered light is weaker in the central regions than in the lateral regions can be compensated (compare FIG. 4A), while at the same time amplification is a different area of the optical image. Optionally, the output signal directly proportional to the result of each scattered light intensity / control (compare FIG. 4A) and each amplification coefficient (compare FIG. 4B) can be selected to be approximately constant intensity; By this technical measure the quality of the results obtained using the first embodiment shown in FIG. 1 is decisively improved.

The first embodiment shown in FIG. 2 is not only provided on the optical system 20 but also on the finger support surface 30 in that no transmissive material for the light of the light sources 10 is provided, but above all, the light source. The field 10 is disposed on the side of the finger support surface 30 facing in the direction of the sensor unit 40, that is, in FIG. 2 is located below the finger support surface 30, It is distinguished from the first embodiment shown in FIG.

The above is directed to the point where the light from the light sources 10 is radiated in the opposite direction from the sensor unit 40 while radiating in the direction of the side of the finger support surface 30 provided for supporting the finger front part. It is a precondition. In other words, the front face of the individual's finger to be identified is illuminated from the side down.

Considering the second embodiment of the present invention shown in FIG. 2, it should also be mentioned in particular that part of the adaptive light control (= ALR or ALC = "adaptive light control"), in other words "intelligent light control". Is that the absorptivity of the filter 90 can be variably formed over different regions x of the optical image (compare FIGS. 4A and 4C).

As a background of the above, the intensity distribution of light scattered inside the front of the finger and the resulting contrast are not uniform or constant over the entire width (x) of the optical image, but rather the central region of the optical image rather than the edge regions of the optical image. Are greater within the field of view (compare the chart in FIG. 4A where the contrast of light scattered inside the front of the finger is schematically shown over the width x of the optical image); This is because above all, the light sources 10 are arranged on the side of the finger support surface 30, and the light of the light sources 10 is directed in the opposite direction from the sensor unit 40, supporting the front of the finger. It is associated with the radiation on the side of the finger support surface 30 which is provided for. This results in less light reaching the central regions covered by the finger fronts on the side of the finger support surface 30 facing away from the sensor unit 40 than in the side regions, whereby scattered light The intensity and (in this regard, directly proportional) contrast is weaker in the central regions than in the lateral regions.

For the second embodiment of the invention, which is specified according to FIG. 2 to eliminate the above deficiency, the density of the optical filter 90 and thus the absorption in the edge regions of the optical image is determined by the filter in the central regions of the optical image. Approximately 90 decibels or about 6 decibels higher than the absorptance of 90 (the absorbance of the selected filter 90 in the device for personal identification of FIG. 2 is approximately the width x of the optical image. Comparison of the diagrams in FIG. 4C, shown across).

Thereby it can be compensated that the intensity and contrast of the scattered light is weaker in the central areas than in the lateral area (compare FIG. 4A), in the manner carried out using optical modulation, while at the same time the absorption is optionally Over different areas x of the optical image, an output signal proportional to the ratio consisting of each scattered light intensity / contrast (compare FIG. 4A) and each absorbance (compare FIG. 4C) can be selected such that it is approximately constant in intensity. do ; By this technical measure the quality of the results obtainable using the second embodiment shown in FIG. 2 is decisively improved.

In addition, in the three embodiments of the present invention shown in FIGS. 1 to 3A, the light sources 10 are disposed laterally spaced from the sensor unit 40. This separation of the structural light sources 10 and the sensor unit 40 avoids the fact that light arrives directly from the light sources 10 into the sensor unit 40 in order to achieve an orderly operation of the device. It has advantages only; Rather, only light having previously been scattered inside the front face of the finger and having information relating to the skin strip or protrusions, i.e. information relating to the fingerprint, must reach within the sensor unit 40.

The first and second embodiments shown in FIGS. 1 and 2 are, in fact, originating from the front face of the finger and passing light having an optical image of the fingerprint through the finger support surface 30 to the sensor unit 40. It is distinguished from the third embodiment shown in FIG. 3 in that the optical fibers in the finger surface 30 are actually arranged in parallel with each other so as to ensure transmission in order.

As an alternative method in this regard, the optical fibers 310 in the finger support surface 30 of the third embodiment (compare FIGS. 3A, 3B and 3C) are actually bidirectional, arranged at an angle of approximately 45 degrees to each other. Have In this regard, the optical fibers 310 and 320 in the finger support surface 30 are arranged layer by layer. In other words, the optical fibers 310 and 320 in one layer are actually arranged parallel to each other, and the optical fibers 310 and 320 of the layers adjacent to each other are disposed at an angle of approximately 45 degrees to each other.

In this regard, in the case of the third embodiment (compare FIGS. 3A, 3B and 3C), the optical fibers 320 of the finger support surface 30 disposed in one direction at an angle of approximately 45 degrees with respect to the other direction are used as the light source. Optical fibers of the finger support surface 30 which are provided for transmitting the light of the field 10 on the side of the finger support surface 3 facing in the opposite direction of the sensor unit 40, while being disposed in the other direction. 310 is provided for transmitting an optical image of the fingerprint to the sensor unit 40.

Of particular relevance to this association is the use of two preferred orientations for the optical fibers 310 and 320, shown in FIGS. 3A, 3B and 3C, in FIGS. 1 and 2. The arrangement of the optical system 20 is according to the point that the uniform illumination of the front face of the finger is ensured by the optical fibers 320 of the finger support surface 30 which are arranged in one direction which consists of an approximately 45 degree angle to the other direction. It may be out of date.

In this regard, irrespective of the view out of the optical system 20, an inflation portion is provided that extends to the area beyond the light sources 10 with respect to the finger support surface 30. The light sources are thereby covered and protected from interference by hand (compare FIGS. 2 and 3).

In the second embodiment of the invention shown in FIG. 2, since the sensor unit 40 only has to reach the light scattering from the front face of the finger, which naturally has information relating to the optical image of the fingerprint, the finger support surface 30 Inside) two blocking layers 130 are provided. The blocking layers prevent transmission of light of the light sources 10. By using the blocking layers 130, the light measured from the light sources 10 is prevented from reaching the sensor unit 40 directly without being scattered in the finger front part.

For the same purpose as the blocking layers 130 in the finger support surface 30 (compare FIG. 2), two blocking layers 140 are used. The blocking layers are always provided between the light sources 10 and the sensor unit 40 in the three embodiments of the invention shown in FIGS. 1 to 3A, and likewise the light of the light sources 10. This does not allow transmission.

It should also be noted that in the third embodiment of the invention shown in FIG. 3A (comparable to the first embodiment of the invention shown in FIG. 1) it is also directed in the opposite direction from the light sources 10. The finger support surface 30 is coated with a substantially commercial varnish with a transmissive material 80 for the light of the light sources 10, ie the transmissive material 80 for infrared. The finger support surface 30, which is thus often responsive, is thus protected from damage, such as scratching and / or contamination by damage, while at the same time cleaning the finger support surface 30 by coating with a light transmissive material 80 It becomes easy.

The third embodiment of the present invention, also shown in FIG. 3A, includes one display device 65 to indicate different modes of operation of the device. An indicator is provided on the display device 65 to signal and direct each mode of operation of the device to the individual to be identified, which also uses a correspondingly blinking light signal to individuals who lack color. Making it possible to determine the respective operating mode of the device.

Finally, the device according to the third embodiment of FIG. 3A is also designed to be able to be switched to a stationary state (= so-called "sleep" mode). This offers potential savings in terms of power consumption of the device. In this connection, there is provided a capacitive circuit 75 integrated in the control device 40, 70, which uses the device according to FIG. 3A when placing the front face of the finger on the finger support surface 30. Again "weather". In other words, it is ready for operation again; In this regard, not only "sleep" but also "wake-up" functions are implemented in the device for personal identification.

Claims (83)

An apparatus for personal identification using at least one fingerprint, At least one light source 10 for illuminating and / or seeing the front of the finger while using light pulses; And At least one optical fiber finger support surface 30 for receiving an optical image of a fingerprint, through which the optical image can be transmitted to at least one sensor unit 40, Within the sensor unit an optical image is convertible into an electrical signal; At the same time at least one light source 10 is disposed on the side of the finger support surface, and at the same time the light of the light source 10 is provided to support the finger front part while being directed in the opposite direction from the sensor unit 40. In the personal identification device which can be radiated on the side of the finger supporting surface 30 Light pulses emitted from at least one light source (10) can be controlled depending on the ambient light conditions. An apparatus according to claim 1, wherein at least one evaluation unit (70a) is arranged behind the sensor unit (40). Apparatus according to claim 1 or 2, characterized in that the amplification of the electrical signal in the sensor unit (40) and / or the evaluation unit (70a) is variable over different areas of the optical image. 4. The apparatus of claim 3, wherein the amplification of the electrical signal in the central regions of the optical image is greater than the amplification of the electrical signal in the edge regions of the optical image. 5. An apparatus according to claim 4, wherein the amplification of the electrical signal in the central regions of the optical image in the central regions of the optical image is about 2 to 3 orders of magnitude larger than the amplification of the electrical signal in the edge regions of the optical image. . 6. The device according to any one of the preceding claims, characterized in that at least one storage unit (70b) is arranged behind the sensor unit (40). Device according to one of the preceding claims, characterized in that at least one control device (40, 70) is provided for controlling the duration and / or intensity of the light pulses. 8. The control device according to claim 7, wherein the control devices (40, 70) At least one evaluation module for adapting the ambient light conditions detected by the detection module to determine the duration and / or intensity of the light pulses; And At least one storage module for storage of a determined threshold for control of the duration and / or intensity of the light pulses. 10. The device according to claim 8, wherein the detection module is formed integrally with the sensor unit (40) and / or as part of the sensor unit (40). 10. Apparatus according to claim 2 and 8 or 9, characterized in that the evaluation module is formed integrally with the evaluation unit (70a) and / or as part of the evaluation unit (70a). Device according to one of the claims 6 and 8 to 10, characterized in that the storage module is formed integrally with the storage unit (70b) and / or as part of the storage unit (70b). Apparatus according to any one of claims 7 to 11, characterized in that the control device (40, 70) is formed as at least one logic member and / or as at least one logic circuit. 13. An apparatus according to claim 12, wherein at least one standard logic member or one programmable logic circuit (FPGA = field programmable gate array) is provided as control device (40, 70). 14. A control device according to any one of claims 7 to 13, wherein the control devices 40, 70 are formed as at least one digital signal processing unit (DSP = digital signal processor) and / or as at least one microcontroller. Device characterized in that. 15. An apparatus according to any one of the preceding claims, wherein an apparatus for transitioning to a stationary state is provided. 16. An apparatus according to claim 15, wherein at least one capacitive circuit (75) is provided, wherein the apparatus is brought to a standstill after a preset period of nonuse. Device according to one of the claims 7 to 14, characterized in that the capacitive circuit (75) is integrated into the control device (40, 70). 18. The device according to any one of the preceding claims, wherein one or more light sources (10) are provided. Device according to claim 18, characterized in that four light sources (10) are provided. 20. The device according to claim 18, wherein the light sources are arranged in a symmetrical fashion. 21. The device according to at least one of claims 18 to 20, characterized in that the light sources (10) are arranged around the finger support surface (30) laterally or in the form of a ring. 22. The device according to any one of claims 18 to 21, characterized in that the light sources (10) are evenly distributed and arranged around the finger support surface (30). 23. The method according to any one of claims 18 to 22, wherein each period and / or each intensity of the light pulses emitted from the respective light sources 10 can be selectively controlled adapted to the ambient light conditions. Device characterized in that. 24. The method according to any one of claims 18 to 23, characterized in that each period and / or each intensity of the light pulses emitted from the respective light sources 10 can be controlled independent of each other. Device. The method according to any one of claims 18 to 24, wherein each period and / or each intensity of the light pulses emitted from the respective light sources 10 can be controlled in dependence on a preset threshold. Characterized in that the device. 26. The device according to any one of the preceding claims, characterized in that the light sources (10) are arranged on the side of the finger support surface (30) facing in the direction of the sensor unit (40). 27. A device according to any one of the preceding claims, characterized in that the light sources (10) are arranged laterally spaced from the sensor unit (40). 28. The finger support surface 30 according to any one of claims 1 to 27, wherein the light of the light source 10 is directed in the opposite direction of the sensor unit 40 and is provided for supporting the finger front part. A device which can be radiated from a side on a side. 29. The device according to any one of the preceding claims, wherein the light source (10) is formed as a pulsed light source. 30. An apparatus according to claim 29, wherein the light source (10) is designed to emit light pulses having an impulse period of approximately zero milliseconds to approximately 90 milliseconds. 31. An apparatus according to claim 29 or 30, wherein at least one pulse generating unit is provided for controlling the light source (10). 32. An apparatus according to at least one of the preceding claims, characterized in that at least one display device (65) is provided for indicating different modes of operation of the apparatus. 33. The device according to claim 32, wherein the display device (65) comprises at least one monochromatic or multicolor indicator, which indicator signals and indicates different modes of operation of the apparatus. 34. An apparatus according to claim 32 or 33, characterized in that the display device (65) is integrated into the light source (10) and / or the display device (65) and the light source (10) are integrally formed. 35. Apparatus according to any one of claims 32 to 34, characterized in that the display device 65 signals and instructs different modes of operation of the device with at least one flashing and / or pulsating light signal. . 36. Apparatus according to any one of the preceding claims, characterized in that at least one optical system (20) is arranged behind the light source (10). 37. The optical system of claim 36, wherein the optical system 20 deflects the light emitted from the light source 10 on the side of the finger support surface facing away from the sensor unit 40, and / or the optical system 20 10. An apparatus characterized by distributing light emitted from (10) evenly and / or diffusely on the side of the finger support surface (30) facing away from the sensor unit (40). 38. The optical system of claim 36 or 37, wherein the optical system 20 is at least one filter, at least one lens, at least one prism, at least one optical fiber light guide, at least one optical guide member, and And / or formed as at least one mirror. 39. An apparatus according to any one of claims 36 to 38, wherein the optical system (20) is made of plastic. 40. The side of an optical system 20 at least facing away from the light source 10 is coated with a transmissive material for infrared and / or visible light. Characterized in that the device. 41. At least one finger guide according to any one of claims 1 to 40 on the side of the finger support surface 30 provided for supporting the finger front part while facing away from the sensor unit 40. Device is provided. 42. The device of claim 41, wherein the finger guide is ergonomically shaped. 43. An apparatus according to at least one of claims 36 to 40, wherein the optical system (20) is formed as a finger guide. The side of the finger support surface 30 facing at least in the opposite direction from the sensor unit 40 is coated with a transmissive material for infrared and / or visible light. The device characterized in that. 45. A device according to claim 40 or 44, characterized in that it is a varnish if it is a transparent material for infrared and / or visible light. 46. An apparatus according to any one of the preceding claims, wherein the light source (10) is a light emitting diode (LED). 47. An apparatus according to at least one of the preceding claims, characterized in that the light source (10) emits infrared radiation. 48. The apparatus of claim 47, wherein the infrared light has a wavelength of approximately 900 nanometers. 49. An apparatus according to at least one of the preceding claims, characterized in that the light source (10) emits infrared rays of two different wavelengths. 50. An apparatus according to at least one of the preceding claims, wherein the light source (10) has an output from approximately 0.1 milliwatts to approximately 5 watts. 51. The device of claim 50, wherein the light source (10) has an output from approximately 2 milliwatts to approximately 100 milliwatts. 52. An apparatus according to any one of the preceding claims, characterized in that the sensor unit (40) is arranged on at least one support unit (50). 53. The apparatus according to claim 52, wherein the support unit (50) is disposed on at least one printed circuit board unit (60). 54. The optical fiber according to any one of claims 1 to 53, wherein the optical fibers 310 in the finger support surface 30 are actually oriented perpendicular to the incidence and / or radiation planes of the finger support surface 30. The device characterized in that. 55. An apparatus according to any one of the preceding claims, characterized in that the optical fibers (310) in the finger support surface (30) are actually arranged parallel to one another. 55. The optical fiber (310, 320) of the finger support surface (30), in fact, comprises in both directions, said directions being arranged at an angle (α) to each other. The device characterized in that. 57. The optical fiber according to claim 56, wherein the optical fibers 310, 320 in the finger support surface 30 are arranged in layers, and at the same time the optical fibers 310, 320 in one layer are actually arranged parallel to each other, And the optical fibers (310, 320) of layers adjacent to each other are arranged at an angle (α) to each other. The optical fibers 320 of the finger support surface 30 disposed in one direction at an angle α with respect to the other direction are directed from the sensor unit 40 in the opposite direction. Optical fibers 310 of the finger support surface 30 disposed in the other direction are provided for transmitting light on the side of the finger support surface, which is to transmit an optical image of the fingerprint to the sensor unit 40. Apparatus, characterized in that provided. The at least one portion of the optical fibers 310, 320 in the finger support surface 30 is at least partially absorbent in the form of a coating and / or in the form of a wrapping. A device characterized by being surrounded by materials. 60. The at least one portion of the optical fibers 310, 320 in the finger support surface 30 is at least in part in the form of a coating and / or in the form of a wrap in the reflective material. The device characterized by being surrounded by. 61. The device according to claim 1, wherein the finger support surface (30) comprises one inflation portion extending into the area beyond the light source (10). 63. The device according to any one of the preceding claims, wherein at least one light impermeable barrier layer (130) is provided inside the finger support surface (30). 63. The apparatus of claim 62, wherein the blocking layer (130) is realized in the form of a sealed optical fiber (310). 64. An apparatus according to any one of the preceding claims, characterized in that at least one light impermeable blocking layer (140) is provided between the light source (10) and the sensor unit (40). 65. The device of claim 62 or 64, wherein the material of the light impermeable barrier layer (130, 140) is a varnish. 66. An apparatus according to any one of the preceding claims, wherein at least one filter (90) is provided. 67. The apparatus of claim 66, wherein the filter (90) is a linear filter. 68. The device according to claim 66 or 67, wherein a filter (90) is arranged between the finger support surface (30) and the sensor unit (40). 70. The filter unit according to any one of claims 66 to 68, wherein the filter (90) is on the side of the finger support surface (30) facing away from the sensor unit (40) and / or of the sensor unit (40). Device on the side of the finger support surface (30) facing in the direction. 70. An apparatus according to any one of claims 66 to 69, wherein a filter (90) is provided in the finger support surface (30). 71. An apparatus according to any one of claims 66 to 70 wherein the filter (90) has an absorption of approximately 99%. 72. The apparatus according to any one of claims 66 to 71, wherein the absorptivity of the filter (90) is variable over different regions of the optical image. 73. The apparatus of claim 72, wherein an absorption of the filter (90) in the edge regions of the optical image is greater than an absorption of the filter (90) in the central regions of the optical image. 74. The method of claim 73, wherein the absorption of filter 90 in the edge regions of the optical image is approximately two to three orders of magnitude greater than the absorption of filter 90 in the central regions of the optical image, and / or at approximately 6 decibels. Approx. 10 decibels greater. 75. The sensor unit 40 according to any one of the preceding claims, wherein the sensor unit 40 is directly adjacent the finger support surface 30, and / or the sensor unit 40 is located in the room of the finger support surface 30. A device characterized by being bordered on a slope. 76. The device according to any one of the preceding claims, wherein the sensor unit (40) comprises at least one photosensitive surface and / or at least one photosensitive layer. 77. An apparatus according to any one of the preceding claims, wherein the sensor unit (40) operates based on a semiconductor. 78. The apparatus of claim 77, wherein the sensor unit (40) operates based on silicon. 79. An apparatus as claimed in any preceding claim, wherein the sensor unit (40) comprises at least one component based on CMOS technology or at least one circuit based on CMOS technology. 80. An apparatus according to any one of the preceding claims, wherein the sensor unit 40 comprises at least one charge coupling component or at least one charge coupling circuit (CCD = charge coupling device). . 81. An apparatus according to at least one of the preceding claims, wherein the apparatus is designed for life identification (so-called "life sustaining"). 83. An apparatus according to claim 49 and 81, wherein the apparatus is designed to determine oxygen saturation in the blood of the finger shear surface by comparing the results obtained for two different wavelengths. 83. An apparatus according to at least one of the preceding claims, which is operated by a battery.