Ultrasound acquisition device comprising a protective film

Abstract

The present invention relates to an ultrasound acquisition device (100) comprising at least one acquisition surface (102) configured for at least one element to be arranged thereon during an acquisition by the ultrasound acquisition device (100), and comprising a film (108) that is movable in the plane of the acquisition surface (102) so that a portion of the film (108) which is protected in a housing (104) of the ultrasound acquisition device (100) prior to the acquisition can be moved to form the acquisition surface (102) during the acquisition.

Description

B23174PCT - Skin Interface Conveyor DESCRIPTION Ultrasonic capture device including a protective film

[0001] The present application claims priority from French patent application number 24 / 13883, filed on December 11, 2024, entitled "Ultrasonic capture device comprising a protective film", which is incorporated by reference to the fullest extent permitted by law. technical field

[0002] This description generally concerns the field of capture devices based on reading and measuring information by ultrasonic transduction, finding applications for example in the fields of biometric identification, medicine, non-destructive testing, or even in other technical fields such as consumer fields. Previous technique

[0003] A biometric identification device is used to verify or determine the identity of a device user based on a measurement of at least one of the user's biometric characteristics, such as a fingerprint, facial shape, iris pattern, retinal pattern, etc. The various techniques for measuring these characteristics each have advantages and disadvantages depending on several criteria, including: the error rate (more or less significant), the ease or difficulty of stealing the template against which the measurements are compared, the ability to detect forgeries, and whether or not the device proves the user is alive. B23174PCT - Skin Interface Conveyor ease and comfort of use, required sensor size, required energy consumption, etc.

[0004] In the case of a biometric identification device by ultrasonic transduction in which the measurement of a biometric characteristic involves contact between the device and the user, there arises the problem of possible contamination, cleanliness, and also the protection of the capture surface of the device on which the contact must be made.

[0005] These problems are also found for capture devices other than biometric identification devices, for example in the medical field, non-destructive testing, or in other technical fields. Summary of the invention

[0006] There is a need to propose an ultrasonic capture device, or ultrasonic transduction capture device, that does not present at least some of the disadvantages of existing solutions.

[0007] One embodiment overcomes all or part of the disadvantages of known solutions and provides an ultrasonic capture device comprising at least one capture surface configured so that at least one element is disposed on it during capture by the ultrasonic capture device, and comprising a film movable in the plane of the capture surface such that a portion of the film protected in a housing of the ultrasonic capture device before capture can be moved to form the capture surface during capture.

[0008] According to a particular method of execution, the film has a strip-like form. B23174PCT - Skin Interface Conveyor

[0009] According to a particular embodiment, the ultrasonic capture device further includes rollers arranged in the housing of the ultrasonic capture device and configured to move the film along its length prior to capture.

[0010] According to a particular embodiment, the rollers are configured to move the film such that it unwinds from one of the rollers and winds around a second of the rollers.

[0011] According to a particular embodiment, the rollers are configured to move the film as it unwinds from a first roller and winds around a second roller prior to capture, and as it unwinds from the second roller and winds around the first roller after capture.

[0012] According to a particular embodiment, the film forms a belt configured to be set in motion by the rollers.

[0013] According to a particular embodiment, the film comprises at least a first portion configured to form the capture surface during capture, and at least a second protective portion configured to take the place of the first portion after capture, and wherein the first portion is protected in the casing after capture.

[0014] According to a particular embodiment, the film comprises several first portions and several second protective portions arranged alternately next to each other.

[0015] According to a particular embodiment, the ultrasonic capture device further comprises an ultrasonic transducer circuit and an acoustic coupling element B23174PCT - Skin Interface Conveyor arranged between the ultrasonic transducer circuit and the capture surface.

[0016] According to a particular embodiment, the acoustic coupling element comprises a liquid and / or a gel.

[0017] According to a particular embodiment, at least one side of the film intended to form the capture surface is pre-coated with lubricant.

[0018] According to a particular embodiment, the ultrasonic capture device further comprises at least one reservoir configured to store a lubricant and communicating with the capture surface such that the lubricant can be dispensed onto the capture surface through the film.

[0019] According to a particular embodiment, the ultrasonic capture device further comprises a lubricant storage compartment and / or a lubricant coating device configured to apply the lubricant to at least one face of the film intended to form the capture surface when the portion of the film protected in the housing is moved to form the capture surface.

[0020] According to a particular embodiment, the ultrasonic capture device is configured to detect the presence of the element near the capture surface and to control the movement of the protected portion of the film in the housing when the element is detected near the capture surface.

[0021] According to a particular embodiment, the ultrasonic capture device corresponds to a biometric identification device configured to implement biometric identification from a part of a user's body intended to be placed on the capture surface. B23174PCT - Skin Interface Conveyor Brief description of the drawings

[0022] These features and advantages, as well as others, will be described in detail in the following description of particular embodiments, given by way of non-limiting example, in relation to the attached figures, among which:

[0023] - Figure 1 schematically represents an ultrasonic capture device according to a first embodiment;

[0024] - Figure 2 schematically represents an ultrasonic capture device according to a first variant of the first embodiment;

[0025] - Figure 3 schematically represents an ultrasonic capture device according to a second variant of the first embodiment;

[0026] - Figure 4 schematically represents a lubricant coating device for an ultrasonic capture device;

[0027] - Figure 5 schematically represents an ultrasonic capture device according to a second embodiment;

[0028] - Figure 6 schematically represents an ultrasonic capture device according to a third embodiment;

[0029] - Figure 7 represents different positions of a protective film of an ultrasonic capture device according to a variant of the first embodiment. Description of the implementation methods

[0030] The same elements have been designated by the same reference numerals in the different figures. In particular, structural and / or functional elements common to the different embodiments may have the same reference numerals and may have identical structural, dimensional and material properties. B23174PCT - Skin Interface Conveyor

[0031] For the sake of clarity, only the steps and elements necessary for understanding the described embodiments have been shown and are detailed. In particular, various components (ultrasonic transducer circuit, moving film actuator, detector for the presence of an element near the capture surface, etc.) and various steps implemented (image acquisition, image processing, minutiae determination, calculations performed, etc.) are not detailed. Those skilled in the art will be able to implement these components in detail based on the functional description provided here.

[0032] Unless otherwise specified, when referring to two connected elements, this means directly connected without any intermediate elements other than conductors, and when referring to two coupled elements, this means that these two elements can be connected or linked through one or more other elements.

[0033] In the description that follows, when referring to absolute positional qualifiers, such as the terms "front", "back", "top", "bottom", "left", "right", etc., or relative positional qualifiers, such as the terms "above", "below", "superior", "inferior", etc., or to orientational qualifiers, such as the terms "horizontal", "vertical", etc., unless otherwise specified, reference is made to the orientation of the figures in a normal position of use.

[0034] Unless otherwise specified, the expressions "approximately", "roughly", "about", and "on the order of" mean within 10%, preferably within 5%.

[0035] Throughout the document, the term "vasculature" is used interchangeably to refer to blood vessels. B23174PCT - Skin Interface Conveyor or micro-blood vessels, of artery and / or vein type, and is used as a synonym for the term "microvasculature".

[0036] An ultrasonic capture device 100 according to a first embodiment is described below in relation to figure 1.

[0037] In the various embodiments described below, the device 100 is configured to implement biometric identification by one or more measurements of at least one biometric characteristic of a part of the user's body. Furthermore, in the examples described below, this part of the user's body corresponds to a single finger. Alternatively, several fingers of the user or other parts of the user's body can be used to perform biometric identification by the device 100.

[0038] Device 100 includes a capture surface 102 on which the finger of the user of device 100 is intended to be placed during biometric identification.

[0039] The device 100 also includes a housing 104 in which various elements of the device 100 are arranged. In the example embodiment visible in Figure 1, the capture surface 102 is arranged at the level of an upper face 106 of the housing 104.

[0040] The device 100 further comprises a film, or a thin layer, 108, a portion of which forms the capture surface 102 during a measurement by the device 100. For example, the film 108 may comprise one or more of the following materials: polyethylene, poly(ethylene terephthalate) (PET), polyolefin, polytetrafluoroethylene (PTFE), poly(vinyl chloride) (PVC), polybutadiene. Generally, the film 108 may comprise a single layer of a single material, or a stack of several materials. The thickness of the film 108 B23174PCT - Skin Interface Conveyor, for example, is between 20 µm and 150 µm. In the described embodiment, the film 108 has a strip-like shape, meaning it is significantly longer than it is wide. Alternatively, the film 108 can have a different shape. In the described embodiment, the portion of the film 108 forming the capture surface 102 is accessible to the user through an opening 109 formed in the upper face 106 of the housing 104. Other configurations of the film 108 and the housing 104 are possible.

[0041] In the first embodiment as described here, the device 100 includes rollers arranged in the case 104 and configured to move the film 108 lengthwise prior to the implementation of a capture by the device 100. More particularly, in the first embodiment, the device 100 includes a first roller 110 and a second roller 112 configured to move the film 108 such that, when different captures are implemented, the film 108 unwinds from the first roller 110 and winds around the second roller 112.

[0042] At least one of the rollers 110, 112 can be motorized to allow the movement of the film 108. According to a first example, one of the rollers 110, 112 can be motorized and the other roller can include a mechanism applying a tensile force to the film 108. In this case, it is the rotation of the motorized roller combined with the tensile force of the other roller that allows the film 108 to unwind from the first roller 110, its movement in the plane of the capture surface 102, the maintenance of its tension and its winding around the second roller 112. According to a second example, both rollers 110, 112 can be motorized. B23174PCT - Skin Interface Conveyor

[0043] In the embodiment shown in Figure 1, the device 100 also includes guides 114 (for example cylindrical as in Figure 1) allowing a portion of the film 108 to be held at the level of the upper face 106 of the housing 104. Thus, the film 108 is mobile in the plane of the capture surface 102, and a portion of the film 108 held at the level of the upper face 106 of the housing 104 forms the capture surface 102.

[0044] The device 100 further includes at least one ultrasonic transducer circuit 116 configured to perform an emission and reception of ultrasonic signals during the captures implemented by the device 100. In the example embodiment visible in Figure 1, the part of the film 108 located opposite the circuit 116 forms the capture surface 102.

[0045] The circuit 116 may include a plurality of ultrasonic transducers configured to perform the image acquisitions required for biometric identification. The ultrasonic transducers are, for example, arranged in a matrix or in another manner suitable for the captures to be performed. The number of ultrasonic transducers in the circuit 116 may depend on the dimensions of the capture surface 102, the dimensions of each ultrasonic transducer, the resolution of the measurements to be performed by the device 100, etc. The circuit 116 may, for example, include CMUT-type transducers. (in English, "Capacitive Micromachined Ultrasonic Transducer" or PMUT type ("Piezoelectric Micromachined Ultrasonic Transducer" or other type.

[0046] In the embodiment shown in Figure 1, the device 100 also includes a coupling element B23174PCT - Acoustic conveyor skin interface 118 is disposed between the circuit 116 and the capture surface 102. For example, this acoustic coupling element 118 may comprise a liquid or gel disposed in a cavity interposed between the circuit 116 and the capture surface 102. Such an element could be, for example, water, an aqueous solution, or an aqueous gel, this element having the advantage in this case of exhibiting a velocity and acoustic impedance values ​​close to those of the biological tissues of the finger. Alternatively, a different acoustic coupling element 118 may be used and interposed between the circuit 116 and the capture surface 102.

[0047] The characteristics of the acoustic coupling element 118 can be such that they give it good acoustic properties to ensure good acoustic coupling (i.e., low attenuation in the transmission of acoustic waves) between the capture surface 102 and the circuit 116. Such acoustic coupling can be achieved by ensuring good acoustic impedance matching either between the circuit 116 and the target (the target corresponding to the user's finger in the example described), or between the circuit 116 and the acoustic impedance value ] a ■ b with Z a and Z b corresponding respectively to the acoustic impedances of circuit 116 and the target.

[0048] In the first embodiment described, most of the film 108 is initially wound around the first roller 110, and one end of the film 108 is attached to the second roller 112. Prior to a capture by the device 100, specifically before the emission of ultrasound by the circuit 116 and before the user's finger is placed against the capture surface 102, a displacement of the film 108 is triggered by the movement of the rollers 110 and 112, so that the capture surface 102 is, at that moment, formed by a portion of the film 108 that was B23174PCT - Skin Interface Conveyor protected within the housing 104. Thus, this portion of the film 108, forming the capture surface 102, is free from any contamination to which the device 100 might have been exposed prior to capture. This replacement of the portion of the film 108 present above the circuit 106, prior to capture, with a "clean," or uncontaminated, portion of the film 108 can be performed for each capture, or after a certain number of captures performed by the device 100 using the same portion of the film 108.

[0049] Furthermore, in the embodiment shown in Figure 1, at least one face of the film 108, which is intended to form the capture surface 102, is pre-coated with lubricant. Thus, replacing the portion of the film 108 forming the capture surface 102 by partially unwinding the film 108 allows the lubricant to be replenished on the capture surface 102.

[0050] In a first embodiment, the device 100 may include at least one reservoir configured to store a lubricant and communicating with the capture surface 102 such that the lubricant can be dispensed onto the capture surface 102 through the film 108. For example, considering the configuration shown in Figure 1, the acoustic coupling element 118 may form this lubricant reservoir, for example, when the acoustic coupling element 118 contains hydrogel, and the lubricant passes through the film 108 via pores and / or holes present in the film 108. For example, lubricant may pass through the film 108 when the user's finger is positioned on the capture surface 102, due to the pressure applied by the finger on the portion of the film 108 forming the capture surface 102.According to another configuration, the lubricant reservoir can be formed by one or more distinct elements of. B23174PCT - Skin Interface Conveyor the acoustic coupling element 118. In addition, the device 100 may include an actuator, for example a micro-pump, configured to control the extraction of lubricant from the reservoir to the capture surface 102. Other types of actuator are possible.

[0051] In a second embodiment, the device 100 may include a lubricant storage compartment 120, or reservoir, configured to apply the lubricant at least to the face of the film 108 intended to form the capture surface 102 when the portion of the film 108 protected in the housing 104 is moved to form the capture surface 102. Figure 2 shows an example of an embodiment of the device 100 according to this second embodiment, the compartment 120 forming a lubricant bath in which the film 108 circulates before forming the capture surface 102. The thickness of liquid obtained on the film 108 after its circulation in the lubricant bath depends in particular on the viscosity of the lubricant and the surface tensions, or "wetting", of the film 108 and the lubricant.In this variant, the application of the lubricating liquid to the film 108 corresponds to a dip coating process also known as "dip coating" in English.

[0052] In both variants above, the amount of lubricant present in compartment 120 can be much greater than that dispensed on the capture surface 102 prior to each capture, which allows lubricant to be dispensed many times on the capture surface 102 before the reservoir or compartment 120 is empty.

[0053] In a third embodiment, the device 100 may include a lubricant coating or dispensing device 122 configured to apply the lubricant at least to the face of the film 108 intended to form B23174PCT - Skin Interface Conveyor capture surface 102 when the portion of the film 108 protected in the housing 104 is moved to form capture surface 102. Figure 3 schematically represents an example of an embodiment of device 100 according to this third variant of embodiment, and Figure 4 represents in more detail an example of an embodiment of the lubricant coating device 122.

[0054] The different embodiment variants described above are not mutually exclusive and can be combined within the same device 100. In all cases, upon contact with the finger, the lubricant present on the capture surface 102 spreads and forms an interface improving the acoustic coupling between the finger and the capture surface 102.

[0055] Furthermore, in the various examples described above, the lubricant can be a gel containing a liquid that performs the lubricating function; this liquid could be water, for example, in the case of a hydrogel.

[0056] In this first embodiment, when the film 108 is fully unwound from the first roll 110, this film 108 can be replaced by another film which is again initially wound around the first roll 110. Alternatively, it is possible for the existing film 108 to be treated and / or cleaned and then repositioned so that it is wound again around the first roll 110 in its initial configuration.

[0057] In the embodiments described above, the film 108 is unwound from the first roll 110 and wound around the second roll 112 as the captures are made. Alternatively, the film 108 may be unwound from the second roll 112 and wound around the first roll as the captures are made. B23174PCT - Skin Interface Conveyor

[0058] An ultrasonic capture device 100 according to a second embodiment is described below in relation to figure 5.

[0059] Device 100 according to this second embodiment comprises all the elements of device 100 according to the first embodiment described above. However, unlike the first embodiment in which rollers 110, 112 are configured to move film 108 as captures are made by device 100, such that it unwinds from the first roller 110 and winds around the second roller 112, rollers 110, 112 are configured, in this second embodiment, to move film 108 such that it unwinds from the first roller 110 and winds around the second roller 112 prior to capture, and such that it unwinds from the second roller 112 and winds around the first roller 110 after capture.In another configuration of this second embodiment, the rolls 110, 112 can be configured to move the film 108 as it unwinds from the second roll 112 and winds around the first roll 110 prior to capture, and as it unwinds from the first roll 110 and winds around the second roll 112 after capture.

[0060] Furthermore, in the described embodiment, the film 108 comprises at least one first portion 124 configured to form the capture surface 102 during capture, and at least one second protective portion 126 configured to take the place of the first portion 124 after capture. Moreover, after capture, the first portion 124 is protected within the housing 104. In Figure 5, the film 108 comprises two first portions 124 between B23174PCT - Skin Interface Conveyor which has a second protective portion 126.

[0061] In Figure 5, the film 108 is shown in a position corresponding to a resting, or standby, configuration of the device 100, that is, a configuration in which no capture is performed. In this resting configuration, the second protective portion 126 is positioned opposite the circuit 116, and the first portion(s) 124 are protected within the housing 104. During a capture by the device 100, the rollers 110, 112 are actuated so that one of the first portions 124 is positioned opposite the circuit 116 and forms the capture surface 102. Thus, in this second embodiment, the first portion(s) 124 of the film 108 are exposed outside the housing 104 only when a capture is performed.In the example of Figure 5 in which the film 108 has two first portions 124, they can alternatively be arranged opposite the circuit 116 to form the capture surface 102 at each capture implemented by the device 100.

[0062] As an alternative to the example of realization described above, film 108 may include a different number of first portions 124 and / or second portions 126.

[0063] As in the first embodiment, the faces of the first portions 124 of the film 108 intended to form the capture surface 102 can be pre-coated with lubricant. The embodiment variants previously described in connection with the first embodiment (reservoir configured to store a lubricant and communicating with the capture surface 102 through the film 108, lubricant storage compartment 120, lubricant coating device 122) can also be applied to this second embodiment. B23174PCT - Skin Interface Conveyor

[0064] An ultrasonic capture device 100 according to a third embodiment is described below in relation to figure 6.

[0065] Device 100 according to this third embodiment comprises all the elements of device 100 according to the second embodiment described above. However, in this third embodiment, the film 108 forms a belt configured to be set in motion by rollers 110, 112. In this configuration, it is possible for rollers 110, 112 to be configured to move the film 108 in one direction and / or the other (for example, clockwise and / or counterclockwise, considering the view in Figure 6).

[0066] Furthermore, in the described embodiment, the film 108 comprises several first portions 124 (two in the example in Figure 6) configured to form the capture surface 102 during capture by the device 100, and several second protective portions 126 (two in the example in Figure 6) configured to replace one of the first portions 124 after capture. Moreover, after capture, the first portions 124 are protected within the housing 104, and one of the second protective portions 126 is positioned opposite the circuit 116.

[0067] In Figure 6, the film 108 is in a position corresponding to a resting configuration during which no capture is performed, and in which one of the second protective portions 126 is positioned opposite the circuit 116. During a capture by the device 100, the rollers 110, 112 are actuated so that one of the first portions 124 is positioned opposite the circuit 116 and forms the capture surface 102. Thus, in this third embodiment and as in the B23174PCT - Skin Interface Conveyor second embodiment, the first portions 124 of the film 108 are exposed outside the casing 104 only during capture implementation.

[0068] As in the previous embodiments, the faces of the first portions 124 of the film 108 intended to form the capture surface 102 can be pre-coated with lubricant. The embodiment variants previously described in connection with the first embodiment (reservoir configured to store a lubricant and communicating with the capture surface 102 through the film 108, lubricant storage compartment 120, lubricant coating device 122) can also be applied to this third embodiment.

[0069] As an alternative to the example of realization described above, film 108 may include a different number of first portions 124 and / or second portions 126.

[0070] In the configuration described in connection with Figure 6, the film 108 comprises several first portions 124 and several second protective portions 126 arranged alternately next to each other. Such a film 108 can be used in the device 100 according to the first and / or second embodiment.

[0071] Figure 7 schematically represents different positions of the film 108 relative to the circuit 116 when this film 108, comprising several first portions 124 and several second protective portions 126 arranged alternately next to each other, is used in the device 100 according to the first embodiment. View a) of Figure 7 corresponds to the position of the film 108 during a first capture, during which one of the first portions 124 forms the capture surface 102. B23174PCT - Skin Interface Conveyor

[0072] After the first capture, the film 108 is set in motion (symbolized by arrows in Figure 7) so that one of the second protective portions 126 adjacent to the first portion 124 forming the capture surface 102 is positioned above the circuit 116. View c) of Figure 7 represents the configuration obtained after this movement, and view b) corresponds to an intermediate position through which the film 108 passes during this movement.

[0073] Next, prior to the implementation of a second capture, the film 108 is set in motion so that the first portion 124 adjacent to the second portion of protection 126 positioned above the circuit 116 and which has not yet served as capture surface 102 is positioned above the circuit 116 and forms the capture surface 102. View d) of figure 7 corresponds to the position of the film 108 during this second capture.

[0074] In all the described modes and embodiments, the device 100 can be configured to acquire at least one surface image of the user's finger placed on and in contact with the capture surface 102; that is, to acquire at least one image of a fingerprint of the finger, formed by the ridges and valleys present on the surface of the skin of the finger placed on the capture surface 102. In the device 100, the acquisition of a surface image of the user's finger placed on and in contact with the capture surface 102 is possible because the ultrasound emitted by the circuit 116 through the film 108 is reflected more strongly by the air present in the valleys of the finger than by the ridges. The difference between the signals received by the circuit 116 that have reflected off the valleys and those that have reflected off the ridges can be exploited. B23174PCT - Skin Interface Conveyor to reconstruct the image of the user's fingerprint present on the capture surface 102.

[0075] Furthermore, the device 100 can also be configured to acquire volume or depth information of the finger placed on and in contact with the capture surface 102 of the device 100, and from which it is possible, for example, to determine, by processing this volume information, global information on the vasculature of the finger, for example a global volume image of the vasculature of this finger, i.e. a capture of images of the blood vessels of the finger of the user of the device 100. According to a particular example, the acquired volume information can correspond to volume or depth images of the finger placed on the capture surface 102.The overall volume information obtained can be deduced from several volume information captured successively at non-zero depths (dimension substantially perpendicular to the capture surface 102) of the finger present on the capture surface 102.

[0076] Alternatively, it is possible for device 100 to be configured to perform only one of the two types of acquisition described above.

[0077] In the various examples and embodiments, the movement of the film 108 can be triggered by a preliminary detection to determine if a finger is placed near the upper face 106 of the housing 104. According to a first example, this detection can be achieved by the emission / reception of ultrasonic signals by the circuit 116 (only some of the detectors of the circuit 116 can be used for this detection). According to a second example, this detection can be achieved by a sensor (not visible in the figures) configured to detect the presence of the user's finger near B23174PCT - Skin Interface Conveyor the top face 106 of the housing 104 and to control the movement of the film 108 when the user's finger is detected near this face 106.

[0078] Device 100 includes other elements which are not described in detail in this description, such as a control circuit for controlling rollers 110, 112, a data processing circuit, etc., which can be implemented using the general knowledge of a person skilled in the art.

[0079] Device 100 can implement additional functions to those previously described, such as contributing to the detection of living things from captured information.

[0080] In the various embodiments, the device 100 allows the user to have a clean and lubricated capture surface 102 when necessary. It also reduces the degradation of the film 108 over time due to its exposure to the ambient atmosphere, such as drying out, the presence of dust or contaminating particles, the effects of UV rays, etc. In addition, the second portions 126 can also have a decorative function.

[0081] In the various configurations, the possible lubrication of the film 108 allows for optimization of the coupling between the element to be captured and the ultrasonic transducer circuit 116, and this without user intervention.

[0082] Furthermore, in the various embodiments described above, the tension and rigidity of the film 108 obtained allow control of the relative position of the finger with respect to the ultrasonic transducer circuit 116, in particular its distance from the circuit 116 in the direction perpendicular to the capture surface 102, as well as the B23174PCT - Skin Interface Conveyor form of the contact obtained between the finger and the capture surface 102 in the plane of the capture surface 102. In addition, the tension and rigidity of the film 108 confer a reaction force when the finger is brought into contact with the capture surface 102, which allows for a slight compression of the biological tissues of the finger, facilitating for example the implementation of anti-hacking countermeasures such as a proof-of-life detection.

[0083] In the various embodiments described above, the ultrasonic capture device 100 corresponds to a biometric identification device. Alternatively, these different examples and embodiments can be applied to a device 100 performing ultrasonic capture that does not correspond to biometric identification, such as capture for medical purposes or for non-destructive testing of an object. In this case, the element intended to be placed on the capture surface of the device may be something other than a part of the user's body, for example, a surface to be inspected by ultrasonic measurement.

[0084] Various embodiments and variations have been described. A person skilled in the art will understand that some features of these various embodiments and variations could be combined, and other variations will become apparent to a person skilled in the art.

[0085] Finally, the practical implementation of the described methods and variants is within the reach of the person in the trade, based on the functional indications given above.

Claims

22 B23174PCT - Skin Interface Conveyor DEMANDS 1. Ultrasonic capture device (100) comprising at least one capture surface (102) configured so that at least one element is disposed thereon during capture by the ultrasonic capture device (100), and comprising a film (108) movable in the plane of the capture surface (102) such that a portion of the film (108) protected in a housing (104) of the ultrasonic capture device (100) prior to capture can be moved to form the capture surface (102) during capture.

2. Ultrasonic capture device (100) according to claim 1, wherein the film (108) has a strip shape.

3. Ultrasonic capture device (100) according to claim 2, further comprising rollers (110, 112) arranged in the housing (104) of the ultrasonic capture device (100) and configured to move the film (108) along its length prior to capture.

4. Ultrasonic capture device (100) according to claim 3, wherein the rollers (110, 112) are configured to move the film (108) as it unwinds from a first of the rollers (110) and wraps around a second of the rollers (112). B23174PCT - Skin Interface Conveyor 5. Ultrasonic capture device (100) according to claim 3, wherein the rollers (110, 112) are configured to move the film (108) such that it unwinds from a first of the rollers (110, 112) and winds around a second of the rollers (110, 112) prior to capture, and such that it unwinds from the second of the rollers (110, 112) and winds around the first of the rollers (110, 112) after capture.

6. Ultrasonic capture device (100) according to claim 3, wherein the film (108) forms a belt configured to be set in motion by the rollers (110, 112).

7. Ultrasonic capture device (100) according to any one of the preceding claims, wherein the film (108) comprises at least a first portion (124) configured to form the capture surface (102) during capture, and at least a second protective portion (126) configured to take the place of the first portion (124) after capture, and wherein the first portion (124) is protected in the housing (104) after capture.

8. Ultrasonic capture device (100) according to claim 7, in which the film (108) comprises several first portions (124) and several second protective portions (126) arranged alternately next to each other. B23174PCT - Skin Interface Conveyor 9. Ultrasonic capture device (100) according to any one of the preceding claims, further comprising an ultrasonic transducer circuit (116) and an acoustic coupling element (118) disposed between the ultrasonic transducer circuit (116) and the capture surface (102).

10. Ultrasonic capture device (100) according to claim 9, wherein the acoustic coupling element (118) comprises a liquid and / or a gel.

11. Ultrasonic capture device (100) according to any one of the preceding claims, wherein at least one face of the film (108) intended to form the capture surface (102) is pre-coated with lubricant.

12. Ultrasonic capture device (100) according to any one of the preceding claims, further comprising at least one reservoir configured to store a lubricant and communicating with the capture surface (102) such that the lubricant can be dispensed onto the capture surface (102) through the film (108).

13. Ultrasonic capture device (100) according to any one of the preceding claims, further comprising a lubricant storage compartment (120) and / or a lubricant coating device (122) configured to apply the lubricant to at least one face of the film (108) intended to form the capture surface (102) when the portion of the film (108) protected in the housing (104) is moved to form the capture surface (102). 25 B23174PCT - Skin Interface Conveyor 14. Ultrasonic capture device (100) according to any one of the preceding claims, configured to detect the presence of the element near the capture surface (102) and to control the movement of the portion of the film (108) protected in the housing (104) when the element is detected near the capture surface (102).

15. Ultrasonic capture device (100) according to any one of the preceding claims, corresponding to a biometric identification device configured to implement biometric identification from a part of a user's body intended to be disposed of on the capture surface (102).

Images