Apparatus for contactlessly recording biometry data from regions of skin

Abstract

The present disclosure relates to an apparatus 1000 for contactlessly recording biometry data from regions of skin. In the process, a sensor optics arrangement 120 of the image recording unit 100 or an emitter optics arrangement 220 of the illumination unit 200, for example, is offset such that the focal planes 135, 235 of the image recording unit 100 and illumination unit 200 overlap substantially in full. Due to this, it is possible to maximally exploit the area of the optical sensor 115 of the image recording unit 100 or the area of the light emitter 215 of the illumination unit 200, for example, and there can be a detection of the biometric features of a hand, in particular of the fingers, with a significantly improved quality as a result. Moreover, the compactness of the apparatus 1000 can be increased further, for example by beam folding by means of reflective optical elements 700.

Description

[0001] DEVICE FOR CONTACTLESS RECORDING OF BIOMETRIC DATA FROM

[0002] SKIN AREAS

[0003] Description

[0004] The present disclosure relates to a device for contactless recording of biometric data from skin areas.

[0005] background

[0006] In the wake of pandemics and rapidly spreading infections, it is becoming increasingly important to capture people's biometric data using contactless methods, for example, fingerprints without touching surfaces.

[0007] Several so-called fingerprint scanners are already known from the prior art, for example from US 2009 / 046 331 A1 or from US 2012 / 076 369 A1, which are designed for the contactless recording of fingerprints by using, for example, a camera as an image recording unit and one or more light sources or projectors as an illumination unit.

[0008] A problem that such systems often have is the combination of the requirement for compactness of such systems and, at the same time, high quality of the captured fingerprints, especially if these systems are to be used for official purposes, for example, since the requirements here are noticeably higher than, for example, in the private or business sector.

[0009] To ensure compact systems, attempts are often made to position the camera and projector as close to each other as possible within the device, thereby resolving the overlap between the camera's depth of field and the projector's depth of field by means of a Scheimpflug arrangement of the camera and projector. However, this configuration leads to image distortion and thus to a partial deterioration in the quality of the captured fingerprints within the image. In view of the disadvantages described above, and based on the prior art described above, it is an object of the present application to provide an improved device for the contactless recording of biometric data from skin areas with improved quality of the captured fingerprints while maintaining a compact design.

[0010] Summary

[0011] The present disclosure relates to a device for contactless recording of biometric data from skin areas.

[0012] In particular, to achieve the above-mentioned object, a device for contactless recording of biometric data from skin regions according to claim 1 is proposed. The dependent claims relate to some exemplary preferred embodiments.

[0013] According to one aspect, in some embodiments, a device for contactless recording of biometric data from skin regions is proposed, comprising: at least one image recording unit comprising an optical sensor and a sensor optics arrangement arranged upstream in the beam path and configured for contactless recording of image data from illuminated skin regions, and at least one illumination unit comprising a light emitter and an emitter optics arrangement arranged downstream in the beam path and configured for illuminating the skin regions to be recorded by the image recording unit, wherein the sensor optics arrangement is arranged offset relative to the optical sensor along the main optical planes of the sensor optics arrangement, or the emitter optics arrangement is arranged offset relative to the light emitter along the main optical planes of the emitter optics arrangement,so that the focal plane section of the image recording unit and the focal plane section of the illumination unit have the greatest possible overlap with each other.

[0014] It was advantageously recognized that by providing an offset of a sensor optics arrangement and / or an offset of an emitter optics arrangement in a device for contactless recording of biometric data, the quantity as well as the quality of the recorded biometric features can be increased, since both the focal plane of the image recording unit can be significantly better superimposed / overlapped with the focal plane of the illumination unit, and no distortion is caused when recording the biometric features by the image recording unit, since a Scheimpflug arrangement can be dispensed with.

[0015] In addition, it was advantageously recognized that when using structured light for illuminating the skin areas, 3D data of the skin areas, in particular the biometric characteristics of the hand or fingers such as the papillary / papillary ridges or the valleys of the valley structure of the skin areas, can be advantageously generated.

[0016] Furthermore, it has been advantageously recognized that an offset of the sensor optics arrangement and / or an offset of the emitter optics arrangement can lead to the provision of reflective optics elements within the device, since the image recording unit and the illumination unit can be moved further apart.

[0017] In addition, it was advantageously recognized that the reflective optical elements, which can fold the beam path of the image recording unit and / or the illumination unit, allow the device to be designed more compactly and yet still be able to maintain the working distance advantageous for capturing the biometric features by means of the image recording unit and illumination unit, even if this distance is longer than the external dimensions of the device itself.

[0018] In summary, the identified advantages can lead to the provision of a more compact device with significantly improved image quality or data quality of the captured biometric data for the contactless capture of biometric characteristics.

[0019] In some preferred embodiments, the offset of the sensor optics arrangement relative to the optical sensor or the offset of the emitter optics arrangement relative to the light emitter can be selected such that the overlap of the focal plane sections of the image recording unit and the illumination unit relative to the maximum possible overlap of the focal plane sections of the image recording unit and the illumination unit is at least 80%, in particular greater than 95%.

[0020] In some preferred embodiments, the offset of the sensor optics arrangement relative to the optical sensor can have an offset between <150% and >50%, in particular an offset between <110% and >90%, or the offset of the emitter optics arrangement relative to the light emitter can have an offset between <60% and >40%. In some preferred embodiments, the sensor optics arrangement can be arranged offset relative to the optical sensor along the main planes of the sensor optics arrangement, and the emitter optics arrangement can be arranged offset relative to the light emitter along the main planes of the emitter optics arrangement.

[0021] In some preferred embodiments, the offset of the sensor optics arrangement relative to the optical sensor and the offset of the emitter optics arrangement relative to the light emitter may each have an offset > 25%.

[0022] In some preferred embodiments, the device may further comprise a system area in which the units of the device are provided, and a recording area for the contactless recording of image data of the skin areas to be recorded, wherein the system area and the recording area are separated from one another by a common boundary surface.

[0023] In some preferred embodiments, the focal plane section of the image recording unit and / or the illumination unit can be arranged in the recording area, wherein the beam path of the image recording unit and / or the beam path of the illumination unit is folded by means of reflective optical elements for contactless recording of the skin areas in the focal plane section, so that the working distance of the sensor optical arrangement and / or the emitter optical arrangement to the respective focal plane section is greater than one of the external dimensions in depth, width and height of the system area of ​​the device.

[0024] In some preferred embodiments, the reflective optical elements may comprise mirrors and / or prisms.

[0025] In some preferred embodiments, the recording area comprising the focal plane sections of the image recording unit and the illumination unit can be designed such that the skin areas to be recorded can be positioned within the depth of field of the focal plane sections of the image recording unit and the illumination unit.

[0026] In some preferred embodiments, the skin areas to be recorded may include areas of the human hand, in particular the palm and fingers, and the recording area may be configured such that multiple fingers can be recorded simultaneously by the image recording unit. In some preferred embodiments, the recording area may be configured such that four fingers, in particular the index, middle, ring, and little fingers, or two thumbs, or the entire palm, or the entire inner side of the hand, can be recorded simultaneously by the image recording unit.

[0027] In some preferred embodiments, the illumination unit may illuminate the skin areas with structured light.

[0028] In some preferred embodiments, the device can further be configured to generate 3D data of the skin regions, in particular as a 3D point cloud, based on the image data of the skin regions that were illuminated by means of structured light and that were acquired by the at least one image recording unit.

[0029] In some preferred embodiments, the light emitter can emit light at a wavelength between 400 nm and 550 nm, more preferably between 450 nm and 500 nm.

[0030] In some preferred embodiments, the system area of ​​the device can have external dimensions in depth, width and height of at most 8", preferably < 180 mm, particularly preferably < 160 mm.

[0031] In some preferred embodiments, the device including the system area and the receiving area can have external dimensions in depth, width and height of at most 8", preferably < 180 mm, particularly preferably < 160 mm.

[0032] Further aspects and their advantages as well as advantages and more specific embodiments of the aspects and features described above are described in the following, but in no way limiting, descriptions and explanations of the attached figures.

[0033] Short description of the characters

[0034] Fig. 1 shows an exemplary arrangement of an image recording unit and an illumination unit, whose focal planes can be superimposed,

[0035] Fig. 2 shows an example of an image recording unit and an illumination unit with crossed focal planes (see illustration (a)) and in Scheimpflug arrangement (see illustration (b)), where the depth of field planes / focal planes can overlap, for example,

[0036] Fig. 3 shows an embodiment of a device for contactless recording of biometric data of skin areas, in which, for example, the sensor optics arrangement is shifted / offset relative to the camera and the emitter optics arrangement relative to the projector along their respective optical main planes,

[0037] Fig. 4 shows, by way of example, the offset of the illuminated section of the focal plane of the illumination unit caused by the offset of the emitter optics arrangement of the projector. Fig. 5 shows, by way of example, the difference between an image captured by means of the Scheimpflug arrangement (see illustration (b)) and an image captured by means of an offset of the sensor optics arrangement of the image recording unit (see illustration (c)) compared to an image captured by means of a sensor optics arrangement and / or emitter optics arrangement arranged symmetrically with respect to the optical sensor and / or light emitter (see illustration (a)).

[0038] Fig. 6 now shows an example of an embodiment of a device with image recording unit, illumination unit and computing unit, wherein the beam paths are folded by means of reflective optics / reflective optical elements,

[0039] Fig. 7 shows an example of a further advantage of offsetting the sensor optics arrangement relative to the camera and / or the emitter optics arrangement relative to the projector in terms of the required installation space,

[0040] Fig. 8 shows an example of a further advantage of offsetting the sensor optics arrangement relative to the camera and / or the emitter optics arrangement relative to the projector in terms of user comfort.

[0041] Detailed description of the figures and preferred embodiments

[0042] Examples and exemplary embodiments of the present disclosure are described in detail below with reference to the accompanying figures. Identical or similar elements in the figures may be designated by the same reference numerals, although sometimes also by different reference numerals. It should be emphasized that the subject matter of the present disclosure is in no way limited or restricted to the exemplary embodiments and their design features described below, but rather further comprises modifications of the exemplary embodiments, in particular those encompassed by modifications of the features of the described examples or by combinations of one or more of the features of the described examples within the scope of protection of the independent claims.

[0043] Fig. 1 shows an exemplary arrangement of an image recording unit 100 and an illumination unit 200, whose sharpness planes / focal planes 135, 235 can overlap for example.

[0044] This shows by way of example how the beam path 130 of the image recording unit 100 applied by the camera 110 and the sensor optics arrangement 120 (for example as the lens of the camera 110) can overlap with the beam path 230 formed by the projector 210 and the emitter optics arrangement 220 (for example as the lens of the projector 210) in the region of the respective focal planes 135 and 235 (see the cross-hatched area).

[0045] In this case, the beam path 130 (with the optical axis 132) of the image recording unit 100 can be applied by means of an optical system, for example comprising the optical sensor 115 of the camera 110 and the lens / lens system 125 (with corresponding optical main planes 125a) of the sensor optics arrangement 120.

[0046] A similar situation can apply to the beam path 230 (with the optical axis 232) of the illumination unit 200, wherein the beam path 230 can be formed by means of an optical system, for example comprising the light emitter 215 of the projector 210 and the lens / lens system 225 (with corresponding optical main planes 225a) of the emitter optics arrangement 220.

[0047] In this case, for example, the sharpness plane / focal plane 135 of the image recording unit 100 and the sharpness plane / focal plane of the illumination unit 235 can be limited to a respective section 137, 237 due to the respective beam path 130, 230, which can each be influenced essentially by the optical sensor 115 and the sensor optics arrangement 120 and / or by the light emitter 215 and the emitter optics arrangement 220, and focal planes 135, 235 limited to these sections 137, 237 can now, for example, superimpose or overlap in certain areas. In addition, each focal plane 135, 235 has a corresponding depth of field 135a, 235a (see arrows in the diagonally hatched areas of the focal planes 135, 235), within which, for example, objects can be captured essentially sharply by the camera 110 or the structure projected by the projector 210 (for example in the case of structured light) can be sharply imaged on the object.

[0048] In the representation of an exemplary interaction of camera 110 and projector 210 shown in Fig. 1, it can be seen by way of example that some of the focal planes 135, 235 overlap (shown with cross-hatching), but also a considerable part of these focal planes 135, 235 do not overlap and thus represent dead zones for possible recordings / captures of fingerprints of a hand, since in these dead zones either only the projector 210 illuminates or only the camera 110 captures images.

[0049] This may, for example, result in certain areas of the optical sensor 115 of the camera 110 not being able to be used for capturing the fingerprints. At the same time, it may result in the used area of ​​the optical sensor 115 requiring a correspondingly high resolution (correspondingly large number of pixels of the optical sensor 115) to ensure the highest possible quality (with a correspondingly high level of detail) of the captured fingerprints (particularly, for example, for official purposes), since only a comparatively small portion of the total area of ​​the optical sensor 115 can be used for capturing the biometric features.

[0050] In addition, for example, the area of ​​the light emitter 215 of the projector 210 cannot be fully utilized, so that the potential for simultaneously capturing the largest possible area of ​​the hand or fingers for capturing biometric data cannot be utilized due to the limited available illumination area, and this can cause a deficit in the efficiency of capturing the biometric data.

[0051] Based on this problem, which is shown by way of example, with the superposition of the focal planes 135, 235, contactless fingerprint capture systems (fingerprint scanners) can, for example, have a Scheimpflug arrangement of image recording unit 100 and illumination unit 200, which is illustrated and described below in Fig. 2. Fig. 2 shows, by way of example, an image recording unit 100 and an illumination unit 200 with crossed focal planes 135, 235 (see illustration (a)) and in a Scheimpflug arrangement (see illustration (b)), wherein the depth of field planes / focal planes 135, 235 can, for example, overlap.

[0052] In contrast to the exemplary arrangement of image recording unit 100 and illumination unit 200 as shown in Fig. 1, the Scheimpflug arrangement (see illustration (b) of Fig. 2) can now be used to try to maximize the area of ​​superposition / overlap of the (sections 137, 237 of the) focal planes 135, 235.

[0053] In this case, the image acquisition unit 100 and the illumination unit 200 are initially aligned convergently to the measurement area / measurement volume. However, this leads to the circumstance that the focal planes 135, 235 initially cross / intersect at a certain angle (see illustration (a) of Fig. 2), so that the possible measurement area for recording fingerprints is initially even smaller (see the cross-hatched area here).

[0054] To counteract this, the sensor optics arrangement 120 and the emitter optics arrangement 220 are now tilted according to the "Scheimpflug" method, thereby creating coplanarity between the two focal planes 135, 235 (see illustration (b) of Fig. 2). This allows, for example, the superposition / overlap of the sections 137, 237 of the focal planes 135, 235 to be increased compared to the exemplary arrangement according to Fig. 1.

[0055] In addition, the Scheimpflug arrangement could potentially make better use of the surfaces of the optical sensor 115 and light emitter 215.

[0056] A significant problem that the Scheimpflug arrangement can pose, however, is perspective distortion of the image of the depth of field in the image acquisition unit 100; this can result in converging lines in the recorded / captured image (see illustration (b) of Fig. 5). In this case, the measuring area in the camera can be displayed in a geometrically distorted manner. For example, a higher resolution of the optical sensor 115 (higher number of pixels of the optical sensor 115) can be used to compensate for this disadvantage in order to achieve a minimum resolution in all image areas that is specified for the respective application (e.g., private or business areas or, with significantly higher requirements, in the government sector).However, the illumination by the illumination unit 200 can also experience negative influences for the same reasons, so that, for example, the measuring area / volume is illuminated unevenly, for example, an illumination of the measuring object coming too much from the side (shadow formation at certain points of the object surface to be detected) and, for example in the case of structured light projected onto the finger / hand, a distortion of this projected structure.

[0057] In order to counteract this problem and thereby advantageously maximize both the overlap of the sections 137, 237 of the focal planes 135, 235 and the use of the area of ​​the optical sensor 115 of the image recording unit 100 and the use of the area of ​​the light emitter 215 of the illumination unit 200, the device 1000 for contactless recording of biometric data of skin areas is to be provided as an example and will be explained below by way of example.

[0058] Fig. 3 shows an embodiment of a device 1000 for contactless recording of biometric data of skin areas, in which, for example, the sensor optics arrangement 120 is shifted / offset relative to the camera 110 and the emitter optics arrangement 220 is shifted / offset relative to the projector 210 along their respective optical main planes 125a, 225a.

[0059] The device 1000 shown here by way of example comprises, as described in Fig. 1, an image recording unit 100 comprising a camera 110 with an optical sensor 115 (for example a CMOS sensor, but can also comprise an optical sensor of a different type) and a sensor optics arrangement 120 with a lens / lens system 125 having the main optical plane 125a, as well as an illumination unit 200 comprising a projector 210 with a light emitter 215 (for example for emitting structured light) and an emitter optics arrangement 220 with a lens / lens system 225 having the main optical plane 225a.

[0060] For example, the sensor optics arrangement 120 (measured along its optical axis 132) can be offset relative to the line of symmetry perpendicular to the optically effective surface of the optical sensor 115 of the camera 110 and arranged essentially in the center of the optically effective surface of the optical sensor 115, and can therefore have an offset (for explanations of the offset, see Fig. 4 and the associated description). This can result in the beam path 130 usable by the optical sensor 115 of the camera 110, and in particular the section 137 of the focal plane 135 of the image recording unit 100, being offset / shifted (shifted / offset along its respective main optical plane 125a) towards the section 237 of the focal plane 235 of the illumination unit 200.

[0061] Conversely, alternatively or in addition to the offset of the sensor optics arrangement 120 of the image recording unit 100, for example, the emitter optics arrangement 220 (measured at its optical axis 232) can be arranged offset from the symmetry line perpendicular to the optically effective surface of the light emitter 215 of the projector 210 and arranged substantially in the center of the optically effective surface of the light emitter 215, and thus also have an offset (for explanations of the offset, see Fig. 4 and the associated description).This can, comparable to the image recording unit 100, result in the beam path 230 (of the projected light) usable by the light emitter 215 of the projector 210, and in particular the section 237 of the focal plane 235 of the illumination unit 200, being offset / shifted (shifted / offset along their respective main optical planes 225a) towards the section 137 of the focal plane 135 of the image recording unit 100.

[0062] Advantageously, the embodiment explained by way of example makes it possible to dispense with any tilting of the lens / lens system 125, 225 of the sensor optics arrangement 120 or the emitter optics arrangement 220 (as in the Scheimpflug arrangement described in illustration (b) in Fig. 2), and yet the overlap of the two sections 137, 237 of the two focal planes 135, 235 (focus planes 135, 235), which are also aligned substantially parallel to one another, can be maximized, in some cases even up to an overlap of more than 95% (where 100% overlap means that at least one section 137, 237 of the focal planes 135, 235 is completely overlaid / overlapped by the respective other section 137, 237 of the focal planes 135, 235).

[0063] In particular, the overlap of the two sections 137, 237 of the focal planes 135, 235 can, for example, be at least 80%, preferably at least 85% and particularly preferably at least 90% of the maximum possible overlap, so that the maximum usable area of ​​the optical sensor 115 of the camera 110 and / or the maximum usable area of ​​the light emitter 215 of the projector 210 can be utilized to the greatest possible extent in order to capture / record the biometric features such as fingerprints and / or the features of an entire palm with the largest possible illumination area (due to the improved utilization of the optically effective surface of the light emitter 215) and the highest possible resolution (number of pixels) of the optical sensor 115 within the largest possible illumination area.Due to the offset of the sensor optics arrangement 120 and the emitter optics arrangement 220 described as an example, the focal planes 135, 235 can be aligned substantially congruently with one another while maintaining their substantially parallelism to one another, which in particular enables a sharp 3D capture of the biometric features such as fingerprints, etc., for example as a 3D point cloud, with a high level of detail in all areas of the sections 137, 37 of the focal planes 135, 235.

[0064] The exemplary embodiment described with the offset of the sensor optics arrangement 120 and the emitter optics arrangement 220 can provide an optimal overlap of the section 237 as the illumination zone and the section 137 as the observation zone of the measurement area / measurement volume. The optical sensor 115 of the camera 110 and the light emitter 215 of the projector 210 thus, for example, do not require more pixels (resolution) than absolutely necessary, since, in the optimal case, no dead zones arise when the sections 137, 237 overlap / cover.

[0065] For an exemplary embodiment of the illumination unit 200, the light emitter 215 of the projector 210 can, for example, emit light at a wavelength between 400 nm and 550 nm, particularly preferably between 450 nm and 500 nm, and project it onto the skin areas to be detected (such as fingers or palm).

[0066] In addition, the light projected by the projector 210 can be designed as structured light, so that a predetermined pattern / structure is projected onto the biometric features to be recorded, for example in order to make the biometric features of the hand or fingers, such as the papillary ridges or the valleys of the valley structure of the skin areas, more efficiently recognizable for the image recording unit 100 and to make it easier to generate 3D data therefrom (for example as a 3D point cloud).

[0067] For an exemplary embodiment of the image recording unit 100, the optical sensor 115 can be designed as a CMOS sensor (or APS) or as a CCD sensor and can have a resolution of 0.3 megapixels (for example, for very small objects to be captured, such as a fingertip) to 50 megapixels (for example, for very large objects, such as the entire hand).

[0068] It should be noted at this point that the lens 125, 225 or the lens system 125, 225 shown in Fig. 3 is only an example and should not be considered a limiting embodiment. The lens 125, 225 / the lens system 125, 225 can be a variety of lens types, for example, converging or diverging lenses, or a combination thereof. Furthermore, for example, a diaphragm may be included or no diaphragm may be included, as well as certain filters or no filters may be included.

[0069] It should also be noted at this point that the beam paths 132, 232 shown in the figures are only examples and should not be considered limiting. Depending on the specific design of the sensor optics arrangement 120 or the emitter optics arrangement 220, the beam paths 132, 232 can have different paths.

[0070] Fig. 4 shows, by way of example, the offset of the illuminated section 237 of the focal plane 235 of the illumination unit 200 caused by the offset of the emitter optics arrangement 220 of the projector 210.

[0071] Therein, the offset is defined in percent as the relative displacement of the illumination area (section 237) generated by the illumination unit 200 with reference to the area size, which in the present example is shown by the dimensions LI and L2.

[0072] If, for example, an offset of ±50% is made along the extent L2 of the originally projected illumination area, as shown by way of example in Fig. 4, the section 237 is offset by half (±50%) of its extent L2 along its extent L2.

[0073] Of course, an offset can also be made along the extension LI (as shown for example with the ±25% of the extension LI along the extension LI) or a superimposed offset of both extensions LI and L2.

[0074] The example shown here concerns the offset of the illumination unit 200, whereby this offset can also be applied analogously to the image acquisition unit 100.

[0075] Furthermore, the offset can also be defined as the ratio of the lateral displacement of the respective optical arrangement (sensor optical arrangement 120 or emitter optical arrangement 220) to the respective chip length of the optical sensor 115 or light emitter 215 in the displacement direction (for example, along the main optical planes 125a of the sensor optical arrangement 120 or along the main optical planes 225a of the emitter optical arrangement 220).

[0076] For example, in device 1000, the offset of sensor optics arrangement 120 relative to optical sensor 115 can have an offset between <150% and >50%, preferably <130% and >70%, particularly preferably <110% and >90%. Alternatively or additionally, for example, in device 1000, the offset of emitter optics arrangement 220 relative to light emitter 215 can have an offset between <60% and >40%, preferably approximately 50%.

[0077] In addition, for example, the offset of the sensor optics arrangement 120 relative to the optical sensor 115 and the offset of the emitter optics arrangement 220 relative to the light emitter 215 can each have an offset > 25%.

[0078] All of these exemplary configurations of the offset of the sensor optics arrangement 120 relative to the optical sensor 115 or of the emitter optics arrangement 220 relative to the light emitter 215 can lead to an optimized or optimal overlap of the illumination area (section 237) of the illumination unit 200 with the measurement area (section 137) that can be captured by the image recording unit 100 within their respective depth of field 135a, 235a.

[0079] Fig. 5 shows, by way of example, the difference between an image captured by means of the Scheimpflug arrangement and an image captured by means of an offset of the sensor optics arrangement 120 of the image recording unit 100 in comparison to an image captured by means of a sensor optics arrangement 120 and / or emitter optics arrangement 220 arranged symmetrically with respect to the optical sensor 115 and / or light emitter 215.

[0080] In illustration (a) of Fig. 5, a hatched area can be seen as an example image, as it would be recorded by the camera if neither a Scheimpflug arrangement nor an offset of the sensor optics arrangement 120 and / or emitter optics arrangement 220 were present, but instead the sensor optics arrangement 120 and / or emitter optics arrangement 220 were each arranged symmetrically with respect to the optical sensor 115 and / or the light emitter 215. As can be seen by way of example, the hatched area in illustration (a) is a rectangle with vertical side lines and horizontal top and bottom edges.

[0081] In comparison, in illustration (b) of Fig. 5, which now reproduces the image using a camera 110 in a Scheimpflug arrangement (see also Fig. 2, illustration (b)), it is very clearly visible how the original, hatched rectangle is distorted and becomes more like a trapezoid with an upper, narrower (and thus distorted part of the image) and a lower part that is of normal width compared to the original image. As already described, in order to meet a required minimum quality (minimum resolution) of the objects captured in the images, for example, it may be necessary to use a much higher-resolution optical sensor 115 to reproduce the distorted areas of the image (and thus distorted objects captured in the image) at the required resolution, whereas in the undistorted areas, a simpler (lower-resolution) optical sensor 115 would have been sufficient.This can also lead to the cost of a device being higher due to the chosen Scheimpflug arrangement.

[0082] In further comparison, illustration (c) of Fig. 5 shows how the image captured using an offset sensor optics arrangement 120 is essentially the same as the original image. There is no distortion caused by the image acquisition unit 100. Likewise, there would be no distortion caused by a projected structure, nor shadowing effects or uneven illumination caused by the illumination unit 200.

[0083] Fig. 6 now shows an exemplary embodiment of a device 1000 with image recording unit 100, illumination unit 200 and computing unit 300, wherein the beam paths 132, 232 are folded by means of reflective optics 700 / reflective optical elements 700.

[0084] The device 1000 shown here as an example is divided into a system area 500 and a receiving area 600, which can be separated from each other by a common interface, for example, an optically transmissive element 820 (such as a glass plate 820). However, the interface can also be part of a housing 800, or a combination of the housing 800 and the optically transmissive element 820, or separate the receiving area 600 from the system area 500 without any physical configuration.

[0085] Furthermore, the device 1000 shown by way of example in Fig. 6 can comprise a camera 110 with a sensor optics arrangement 120 and a projector 210 with an emitter optics arrangement 220, wherein both the sensor optics arrangement 120 are arranged offset relative to the camera 110 and the emitter optics arrangement 220 are arranged offset relative to the projector 210, as described in Fig. 3, so that, for example, both the image recording unit 100 and the illumination unit 200 each have an offset. It should be noted at this point that, if necessary, only one of the image recording unit 100 and the illumination unit 200 can have an offset.

[0086] The beam path 132 of the image recording unit 100 and the beam path 232 of the illumination unit 200 are, for example, each deflected / folded within the housing 800 by reflective optical elements 700 before reaching the common focal plane 135, 235. For example, the beam paths 132, 232 pass through an optically transmissive element 820, embodied, for example, as a glass pane 820, before reaching or forming the common focal plane 135, 235.

[0087] It should be noted at this point that the optically transmissive element 820 need not be present, but can also be omitted or replaced by another element. The optically transmissive element 820 / glass pane 820 can advantageously be used, for example, to protect the image acquisition unit 100, illumination unit 200, and / or computing unit 300 located in the system area 500, for example, from contamination, damage, and / or tampering.

[0088] The reflective optical elements 700 can be designed, for example, as mirrors and / or beam-deflecting prisms, or as a combination of these elements (mirror / prism).

[0089] As shown by way of example, the image acquisition unit 100, the illumination unit 200, the computing unit 300, and the reflective optical elements 700 are provided / arranged within the system area 500 of the device 1000. The common focal planes 135, 235 of the image acquisition unit 100 and the illumination unit 200 are located, for example, outside the system area 500 and within the acquisition area 600.

[0090] In this case, the two areas (recording area 600 and system area 500) can, for example, have a comparatively compact design, since the reflective optical elements 700 fold / deflect the beam paths 132, 232 such that the desired working distance (distance between the sensor optics arrangement 120 or emitter optics arrangement 220 to the focal plane 135, 235 along the respective beam path 132, 232) of, for example, approximately twice the diameter (or diagonal) of the cutouts 137, 237 of the focal planes 135, 235 (for example, a working distance of approximately 200 mm with approximately 100 mm diameter / diagonal of the cutouts 137, 237), although the external dimensions in depth Tsoo, width Bsoo and height Hsoo of the system area 500, for example, each amount to a maximum of 8", preferably less than 180 mm, and particularly preferably less than 160 mm.

[0091] A sufficiently large working distance can be particularly advantageous to avoid shadowing effects on the biometric features (such as fingerprints or the valleys of the papillary structures) during the capture of the biometric features. Thus, for example, it may prove advantageous if the beam path(s) 132, 232 are not guided directly from the camera 110 or the projector 210 to the object to be captured (e.g., the palm of the hand or the fingers).

[0092] The folding / deflection of the beam paths 132, 232 by means of the reflective optical elements 700 can be advantageously supported or enabled, for example, by the offset of the sensor optical arrangement 120 relative to the camera 110 and / or by the offset of the emitter optical arrangement 220 relative to the projector 210.

[0093] It may be advantageous that by offsetting the sensor optics arrangement 120 relative to the camera 110 and / or by offsetting the emitter optics arrangement 220 relative to the projector 210, at least one reflective optic 700 can be positioned in the respective beam path 132, 232 without obscuring (or even partially obscuring) the other beam path 132, 232, since, with the same overlap in the focal plane 135, 235, the camera 110 and the projector 210 can be moved further apart.

[0094] In addition, it may be advantageous to fold the beam paths 132, 232 not only once, as shown in Fig. 6, but possibly to fold them several times, for example two or three times, in order to be able to make the device 1000 even more compact, for example.

[0095] In addition, the system area 500 can be further reduced in size, for example depending on the possible arrangement of the reflective optical elements 700 and / or depending on the number of reflective optical elements 700, so that, for example, the external dimensions in depth Tsoo, width Bsoo and height HSOO+HÖOO of the system area 500 including the receiving area 600, for example, each have a maximum of 8", preferably less than 180 mm, and particularly preferably less than 160 mm.

[0096] Furthermore, it may be advantageous if the recording area 600 having the sections 137, 237 of the focal planes 135, 235 of the image recording unit 100 and the illumination unit 200 is designed such that the skin areas to be recorded can be positioned within the depth of field 135a, 235a of the sections 137, 237 of the focal planes 135, 235 of the image recording unit 100 and the illumination unit 200.

[0097] This allows, for example, the biometric characteristics of skin areas (e.g. fingerprints and / or palms) to be captured effectively and in high quality (with a high level of detail), so that high-quality 3D data on the respective captured biometric characteristics can later be created from them.

[0098] In particular, it may be advantageous if the skin areas to be recorded include areas of the human hand, in particular the palm and fingers, and the recording area 600 is configured such that several fingers can be recorded simultaneously by the image recording unit 100. This can further increase the efficiency of capturing the biometric features.

[0099] For example, the recording area 600 can be designed such that 4 fingers, in particular the index, middle, ring and little fingers, or 2 thumbs, or the entire palm of the hand, or the entire inner side of the hand can be recorded simultaneously by the image recording unit 100.

[0100] In addition, for example, the system area 500 can have a computing unit 300 for controlling the image acquisition unit 100 and the lighting unit 200 and for processing the acquired biometric data, wherein the computing unit 300 can alternatively also be provided outside the system area 500. For example, the computing unit 300 of the device 1000 can process the acquired biometric data (for example, convert the image data captured by the image acquisition unit 100 into biometric data of the skin areas, for example into 3D data, in particular into an SD point cloud) and, if necessary, store it in a storage unit 310, wherein the data can also be stored outside the device 1000.

[0101] In addition, the computing unit 300 can compare the processed / calculated biometric data with biometric data already stored in the storage unit 310 and thus detect potential matches.

[0102] Fig. 7 shows, by way of example, a further advantage of offsetting the sensor optics assembly 120 relative to the camera 110 and / or the emitter optics assembly 220 relative to the projector 210 in terms of the required installation space. Illustration (a) of Fig. 7 shows the already known Scheimpflug arrangement, in which both the image acquisition unit 100 (with camera 110 and sensor optics assembly 120) and the illumination unit 200 (with projector 210 and emitter optics assembly 220) are tilted convergently toward one another.

[0103] However, this may result in a required free installation space (see dashed rectangle around the image recording unit 100 and illumination unit 200) which is significantly larger compared to the arrangement with the offset of the sensor optics arrangement 120 relative to the camera 110 and the emitter optics arrangement 220 relative to the projector 210, as shown in illustration (b).

[0104] Or to put it another way: In addition to the already mentioned advantages of the arrangement with offset of the respective optical arrangements 120, 220 relative to the camera 110 or projector 210, advantages can also be gained with regard to the required installation space, so that the device 1000, as shown and described, for example, in Fig. 6, can be designed to be more compact than comparable devices that implement the Scheimpflug arrangement.

[0105] Fig.8 shows, by way of example, a further advantage of the offset of the sensor optics arrangement 120 relative to the camera 110 and / or the emitter optics arrangement 220 relative to the projector 210 in terms of user comfort.

[0106] In particular, the offset of the emitter optics arrangement 220 relative to the projector 210 can provide an advantage over a non-offset emitter optics arrangement 220. In particular, as shown in illustration (a) of Fig. 8, a non-offset emitter optics arrangement 220 can result in the user who wants to have / needs to have their biometric features recorded having to approach so close to the device 1000 (as shown and described, for example, in Fig. 6) that they are dazzled by the light beam projected by the projector 210. This can, of course, be very unpleasant for the user, especially since a projector can have a very bright and powerful light source (for example, like the light emitter 215).

[0107] By contrast, by offsetting the emitter optics arrangement 220 relative to the projector 210, as shown in illustration (b) of Fig. 8, the light beam / light cone emitted by the projector 210 can be directed away from the user, so that the user is not dazzled, even if they have to get very close to the device. It should be noted that only examples or exemplary embodiments of the present disclosure and technical advantages have been described in detail above with reference to the attached figures. However, the present disclosure is in no way limited or restricted to the exemplary embodiments described above and their design features or the described combinations thereof, but further includes modifications of the exemplary embodiments, in particular those which are achieved by modifying the features of the described examples or by combining orPartial combination of one or more of the features of the described examples are included within the scope of protection of the independent claims.

[0108] List of reference symbols

[0109] 100 image acquisition unit

[0110] 110 Camera

[0111] 115 optical sensor

[0112] 120 sensor optics arrangement

[0113] 125 Lens / lens system of the sensor optics arrangement

[0114] 125a Main optical plane of the lens / lens system of the sensor optics arrangement

[0115] 130 Beam path of the image recording unit

[0116] 132 optical axis of the beam path of the image recording unit

[0117] 135 Focus plane of the image pickup unit

[0118] 135a Depth of field of the focal plane of the image recording unit

[0119] 137 Section of the focal plane of the image acquisition unit

[0120] 200 lighting units

[0121] 210 Projector

[0122] 215 light emitters

[0123] 220 emitter optics arrangement

[0124] 225 Lens / lens system of the emitter optics arrangement 225a optical main plane of the lens / lens system of the

[0125] Emitter optics arrangement

[0126] 230 Beam path of the lighting unit

[0127] 232 optical axis of the beam path of the illumination unit

[0128] 235 Focus plane of the lighting unit

[0129] 235a Depth of field of the focal plane of the lighting unit

[0130] 237 Section of the focal plane of the lighting unit

[0131] 300 computing units

[0132] 310 Memory unit of the computing unit

[0133] 500 System area

[0134] 600 recording area

[0135] 700 reflective optics / optical elements

[0136] 800 housings

[0137] 820 Interface between system area and recording area / optically transparent element / glass pane

[0138] 1000 device

[0139] B500 Width of the system area

[0140] H500 Height of the system area

[0141] T500 Depth of the system area

[0142] HÖOO Height of the recording area

Claims

Patent claims 1. Device for contactless recording of biometric data from skin areas, comprising: - at least one image acquisition unit comprising an optical sensor and a sensor optics arrangement positioned in front of it in the beam path, and designed for contactless acquisition of image data from illuminated skin areas, and - at least one illumination unit comprising a light emitter and an emitter optics arrangement arranged downstream in the beam path and configured to illuminate the skin areas to be recorded by the image acquisition unit, wherein the sensor optics arrangement is arranged offset relative to the optical sensor along the principal optical planes of the sensor optics arrangement or the emitter optics arrangement is arranged offset relative to the light emitter along the principal optical planes of the emitter optics arrangement, such that the focal plane section of the image acquisition unit and the focal plane section of the illumination unit have the greatest possible overlap with each other.

2. Device according to claim 1, characterized in that the offset of the sensor optics arrangement relative to the optical sensor or the offset of the emitter optics arrangement relative to the light emitter is selected such that the overlap of the focus plane sections of the image acquisition unit and the illumination unit relative to the maximum possible overlap of the focus plane sections of the image acquisition unit and the illumination unit is at least 80%, in particular greater than 95%.

3. Device according to claim 1 or 2, characterized in that the offset of the sensor optics arrangement relative to the optical sensor has an offset between < 150% and > 50%, in particular an offset between < 110% and > 90%, or the offset of the emitter optics arrangement relative to the light emitter has an offset between < 60% and > 40%.

4. Device according to claim 1, characterized in that The sensor optics arrangement is offset relative to the optical sensor along the main planes of the sensor optics arrangement, and the emitter optics arrangement is offset relative to the light emitter along the main planes of the emitter optics arrangement.

5. Device according to claim 4, characterized in that the offset of the sensor optics arrangement relative to the optical sensor and the offset of the emitter optics arrangement relative to the light emitter each have an offset > 25%.

6. Device according to one of the preceding claims, characterized in that the device further comprises a system area in which the units of the device are provided and a recording area for the contactless recording of image data of the skin areas to be recorded, wherein the system area and the recording area are separated from each other by a common interface.

7. Device according to claim 6, characterized in that the focal plane section of the image acquisition unit and / or the illumination unit is arranged in the recording area, wherein the beam path of the image acquisition unit and / or the beam path of the illumination unit is folded in the focal plane section by means of reflective optical elements for contactless recording of the skin areas, so that the working distance of the sensor optics arrangement and / or the emitter optics arrangement to the respective focal plane section is greater than one of the outer dimensions in depth, width and height of the system area of ​​the device.

8. Device according to claim 7, characterized in that the reflective optical elements comprise mirrors and / or prisms.

9. Device according to one of claims 6 to 8, characterized in that the recording area having the focus plane sections of the image recording unit and the illumination unit is designed in such a way that the skin areas to be recorded can be positioned within the depth of field of the focus plane sections of the image recording unit and the illumination unit.

10. Device according to claim 9, characterized in that The skin areas to be recorded include areas of the human hand, in particular the palm and fingers, and the recording area is designed so that several fingers can be recorded simultaneously by the image recording unit.

11. Device according to claim 10, characterized in that the receiving area is designed such that - 4 fingers, especially index, middle, ring and little fingers, - 2 thumbs up, - the entire palm of the hand, or - the entire inside of the hand can be captured simultaneously by the image capture unit.

12. Device according to one of the preceding claims, characterized in that the lighting unit illuminates the skin areas with structured light.

13. Device according to claim 12, characterized in that the device is further configured to generate 3D data of the skin areas, in particular as an SD point cloud, on the basis of the image data of the skin areas, which were illuminated by means of structured light, captured by the at least one image acquisition unit.

14. Device according to one of the preceding claims, characterized in that the light emitter emits light at a wavelength between 400 nm and 550 nm, particularly preferably between 450 nm and 500 nm.

15. Device according to one of claims 6 to 11, characterized in that the system area of ​​the device has external dimensions in depth, width and height of at most 8", preferably < 180 mm, particularly preferably < 160 mm.

16. Device according to one of claims 6 to 11, characterized in that the device, including the system area and receiving area, has external dimensions in depth, width and height of at most 8", preferably < 180 mm, particularly preferably < 160 mm.

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