FR3005562A1 - FLEXIBLE PASSIVE SENSOR FOR CONTACT LENS - Google Patents

Abstract

The invention relates to a sensor (100, 200, 300) of intraocular pressure for incorporation into a contact lens, comprising: a carrier substrate, and an inductor (101) arranged substantially on a plane of the carrier substrate and comprising at least a turn (102, 103) describing a plurality of turn turns in a substantially spiral geometry. According to the invention, at least one cutout (115a) of the carrier substrate is made at at least one gap (114a) between two successive turn turns of the inductor (101).

Description

The invention relates to the field of passive sensors for incorporation into contact lenses, in particular intended to measure a physiological parameter such as intraocular pressure.

Intraocular pressure is one of the physiological parameters used to diagnose certain diseases of the eye, such as glaucoma. Ambulatory and non-invasive sensors have been developed to measure changes in intraocular pressure in a patient during his daily course. The development of non-invasive sensors allows more and more frequently on the one hand to overcome the invasive methods involving surgical procedures on the patient's eye. On the other hand, the fact of associating these sensors with ambulatory systems also avoids immobilization of the patient and allows an uninterrupted effective follow-up of the evolution of the intraocular pressure or of any other physiological parameter in real life situations. of the patient.

A passive sensor, that is to say not requiring any significant source of energy to operate, realized by means of an electric circuit LC, integrated in a soft contact lens and intended for the monitoring of the intraocular pressure, is known from EP 2 412 305 A1. A variation of the intraocular pressure causes a change in the resonance frequency of the LC circuit which can be detected and thus related to this variation. In particular, the application EP 2 412 305 A1 discloses a sensor comprising a capacitor and an inductance composed of first turns arranged on a first main face of a carrier substrate and second turns arranged on a second main face of the carrier substrate, opposite to the first main face. The document EP 2 412 305 A1 also discloses that the carrier substrate can be removed at least partially from the non-turn and / or capacitor regions, that the two sets of turns can intersect and be interconnected by conductive vias, as well as the capacitor can be formed integrally with the inductor so that its two electrodes are each arranged on one of the two opposite faces of the carrier substrate.

Some practical problems and unexpected constraints have arisen in the manufacture of the sensors and lenses as disclosed in EP 2 412 305 A1, especially when molding the sensor with a contact lens.

In general, the bending of the sensor during molding in a contact lens poses many practical problems and each type of sensor known in the state of the art has more or less rigid areas that may hinder the operation. There is therefore a need in the industry for passive sensors for sensor contact lenses manufactured such that their bending at the time of molding with the contact lens can be effected effectively. The present invention therefore aims to improve the known techniques and sensors of the state of the art to allow better bending and therefore molding of the sensors in contact lenses.

An object of the present invention is achieved with an intraocular pressure sensor for incorporation into a contact lens, comprising a carrier substrate, and an inductance arranged substantially on a plane of the carrier substrate and having at least one turn describing a plurality of turns of turn in a substantially spiral geometry. According to the invention, at least one cutting of the carrier substrate is performed in at least one gap between two successive turn turns of the inductor. Thus a sensor according to the invention may have a structure at least partially in "concentric rings attached", which offers more flexibility when bending. At least one cut is necessary to achieve the invention, but more cuts may also provide an improved concentric ring structure attached, providing even more flexibility to the sensor when bent and incorporated into a contact lens. . To achieve the invention, it is not necessary that the cutout or cuts are made through the entire thickness of the carrier substrate. A cut on a partial thickness or a cut made discontinuously or segmented on the cut section may be sufficient, as long as the remaining layer or the carrier substrate segments are thin enough to tear during bending of the sensor, thereby making a cut through the entire thickness of the substrate or along the entire length of the cut. Preferably, the sensor may further comprise at least one capacitor with a first electrode and a second electrode, characterized in that at least one of the two electrodes of the at least one capacitor can be arranged on the same plane of the carrier substrate as the inductor. It is therefore possible to produce a passive LC circuit, the resonance frequency variations of which can be monitored as a function of the variations of the physiological parameter to be monitored, for example the intraocular pressure. It is also advantageous for the geometry of this at least one capacitor to be at least partially wedged to that of the inductor so as to improve the flexibility of the sensor with respect to known state of the art sensors using capacitors. geometry different from that of inductance. At least one other cut can then be made in at least one gap between said capacitor and the inductor. Just as one or more cuts can be made in at least one gap between turns of the inductor, at least one cut can be made equally and also advantageously between the inductor and the capacitor. The flexibility of the sensor is then even more improved compared to the state of the prior art. Advantageously, the inductor may comprise a first turn starting from a first terminal on the outermost part of the inductor and rotating in a first spiral direction towards the innermost part of the inductor, and a second turn extending the first turn in the same spiral orientation from the innermost portion of the inductor to a second terminal on the outermost portion of the inductor, and the turn turns of the first turn and the turn turns of the second turn can intersect in at least one crossing zone. In particular, the turn turns of the first and second turns can intersect in two crossing zones, preferably diametrically opposite. Such an inductance makes it possible to better confine the electric field lines in the contact lens with respect to inductances used in sensors known from the state of the art. In a variant of an embodiment, the inductor may be arranged in a plurality of series or rings of concentric turns, preferably between two and five rings of turns, preferably three rings of turn turns, spaced apart. radially by interstices of predetermined width at least equal to or greater than the width of a gap between two turns of a turn of the same ring of turn turns, and the at least one cut can be made at least in a gap between two rings of turns of turn. Thus, a sensor according to the invention may comprise preferential interstices in which it is advantageous to produce at least one blank according to the invention. In addition, the fact of arranging the turns of the coil of the inductance in groups of turn turns allows to give more a structure in "concentric rings attached" once the cut or cuts made in the carrier substrate and therefore to improve its flexibility compared to the known sensors of the state of the art to obtain better bending and therefore ultimately better integration to a contact lens. Preferably, each turn ring may then comprise three to ten turn turns. It is advantageous for the patient carrying the lens to have an unobstructed view, even in low light. It is therefore advantageous to maintain the number of turn turns in a suitable range. Preferably, the ring of turns of turn closest to the center of the spiral geometry of the inductor can then comprise more turns of turn than the other rings of turns of turn. In other words, the width of the ring of the innermost turn turns may be larger than the respective widths of the outermost rings. The central zone of the sensor being a little easier to bend during bending on the one hand, and the substrate being wider on the inner ring on the other hand, it is advantageous to arrange more turn turns than in the rings of turns of turn more outside the sensor which are those undergoing a stronger curvature.

In a variant of the embodiment comprising the turn rings, two rings of successive turn turns can be interconnected by at least one conductor bridge, preferably by a single conductor bridge, in particular by a single conductor bridge which can to be arranged at 180 ° of the next conductor bridge between two rings of turn turns, more particularly at crossing zones. It has been observed that conductive bridges arranged diametrically opposite were advantageous for the flexibility of the sensor. Using a single conductive bridge between groups of turn turns allows, once at least one cut made according to the invention, to accentuate the shape concentric rings attached to the sensor during its bending.

Advantageously, at least one of the first turn and the second turn may be composed of a plurality of turn segments connected in the crossing zones. At least one of the turns of the inductor can be segmented to allow simpler crossings between them. In this case, the crossings between the first turn and the second turn, and if necessary the conductive bridges between turn rings, can be advantageously achieved by means of conductive vias and conductive traces. Advantageously, each of the electrodes of the at least one capacitor may be respectively connected to a terminal of the inductor. It is possible to arrange at least one capacitor on an outer periphery or on an inner periphery of the inductor. In either case, it is possible to use connections using conductive vias and conductive traces. Advantageously, the at least one cut can be made by successive arcuate segments leaving carrier substrate bridges between two successive cuts, so that the carrier substrate bridges can tear during molding of the sensor for incorporation into a contact lens. , where appropriate with the exception of crossing areas and areas around conductive bridges. It is therefore possible to cut in segments rather than in a single stroke over the length of the gap. At the time of bending, it is possible for the spaces between segments to tear, thus achieving a single longer cut. It is always preferable not to cut through crossing areas or, where appropriate, conductive bridges between turn rings. Advantageously, the inductor may have a substantially starry geometry. It has been observed that a star-shaped geometry inductor with a succession of branches and valleys, in particular with rounded ends, provides the sensor with sufficient flexibility not to produce folds or wavelets around the edges. a contact lens during molding. It is therefore possible to combine this advantageous aspect with the present invention to provide a sensor more flexible and adaptable to the geometry of a contact lens than the known sensors of the state of the art. Advantageously, the at least one capacitor may have an arcuate geometry depending at least partially on the geometry of the inductor. Thus, in a substantially circular inductance sensor, the capacitor or capacitors may be in an arc, while they may adopt a partially star-shaped arc geometry in the case of a star-shaped inductor. This aspect offers more flexibility than a sensor comprising a capacitor of geometry different from that of the inductor. The objective is also achieved by a contact lens, in particular a soft contact lens, comprising a sensor according to the aspect described above or one of its variants or a combination thereof, in which the sensor is molded. inside the lens. When molding with the lens, the inductor can be bent perpendicular to the first plane of the sensor, which is the plane on which the sensor has been made, following the curvature of the lens. The presence of at least one cut-out in the carrier substrate between turns of the inductor offers improved flexibility compared to the state of the art during bending and thus the incorporation of the sensor according to the invention in a contact lens, which makes it possible in particular to avoid the formation of wavelets or folds at the edge of the lens once the sensor incorporated and thus has an advantage over contact lenses equipped with passive sensors known to the state of art. Various aspects to better understand the present invention and the advantages described above will be detailed in the following, in particular using advantageous embodiments illustrated by means of the accompanying figures, in which: Figure 1 schematically illustrates a example of an embodiment of a sensor according to one of the aspects of the invention; Figure 2 schematically illustrates another example of an embodiment of a sensor according to the invention; Figure 3 schematically illustrates an example of a variant of the embodiment illustrated in Figure 2; and Figures 4A and 4B schematically illustrate an example, not part of the present invention but useful for its understanding, of blanks in a substrate resulting in a structure in "concentric rings attached". In the following, analogous reference signs are used to describe identical elements or playing the same role in the different embodiments. For example, an element designated by the reference sign 101 in a first embodiment may be designated by 201, respectively by 301, in a second, respectively a third, embodiment. It is therefore possible that the description of identical elements or elements playing the same role is not repeated in different embodiments. Figures 1 to 3 schematically show variants of a sensor 100, 200, 300 for measuring a physiological parameter such as intraocular pressure according to embodiments illustrating a combination of several aspects of the present invention.

Figure 1 shows a variant of an embodiment of a sensor 100 according to the invention, here shown flat, for example before bending and / or molding for incorporation into a contact lens, in a view from above. According to one aspect of the invention illustrated in FIG. 1, the sensor 100 comprises an inductor 101, which is arranged essentially on the same first plane of a carrier substrate. The view of FIG. 1 illustrates that the inductor 101 has a substantially star-shaped geometry, comprising a series of branches 104a, 104b, 104c, 104d, 104e, 104f and valleys 105a, 105b, 105c, 105d, 105e, 105f arranged around center 110 of said starry geometry. In the variant of the embodiment illustrated in FIG. 1, the inductor 101 comprises an even number of branches but could, in other embodiments, comprise an odd number of branches. In the case illustrated in Figure 1, the inductor 101 comprises 6 branches, but it could comprise less or more, for example 4 or 5 branches and up to 8 or 9 or 10 branches or more. The distance between the center 110 of the star geometry and the end of each branch 104a, 104b, 104c, 104d, 104e, 104f may be chosen to be substantially less than or equal to the radius of the contact lens in which the sensor 100 will be incorporated. Likewise, the star geometry of the inductor 101 may be chosen such that the distance between the center 110 and the bottom of the valleys 105a, 105b, 105c, 105d, 105e, 105f is substantially less than or equal to the distance between the center 110 and the ends of the two branches 104a, 104b, 104c, 104d, 104e, 104f respectively surrounding each valley 105a, 105b, 105c, 105d, 105e, 105f. The dimensions of the branches 104a, 104b, 104c, 104d, 104e, 104f and the valleys 105a, 105b, 105c, 105d, 105e, 105f can be chosen preferably so as not to hinder the vision of a patient carrying a lens provided with such a sensor 100, especially in the dark or in low light conditions. Other geometries than the starry geometry described for the embodiment illustrated in FIG. 1 are also possible. Thus, the inductances 201, 301 and more generally the sensors 200, 300 of the variants of an embodiment illustrated in FIGS. 2 and 3 may be of essentially circular geometry. Other sensor variants according to the invention could be essentially square, rectangular, triangular, oval, etc. Apart from their geometry, the variants of an embodiment of a sensor 200, 300 according to the invention illustrated in FIGS. 2 and 3, which will be described later, show several of the characteristics of the variant of a sensor 100. according to the invention illustrated in Figure 1.

According to another variant of an embodiment of the invention, which can be combined with the aspects described above or taken independently, the inductor 101 of the embodiment illustrated in FIG. 1 comprises two terminals 106a, 106b which are located on an outer periphery of the inductor 101. The inductor 101 further comprises a first turn 102, starting at the first terminal 106a, and spiraling from the outermost portion of the inductor 101 inwardly of the inductor 101, then extending by a second turn 103, always rotating in the same spiral direction, but from the inner periphery to the second terminal 106b on the outer periphery of the inductor 101. Moreover, since the inductor 101 is on the same first plane of the carrier substrate, the two turns 102, 103 and therefore the two terminals 106a, 106b are also arranged on the same plane. According to a variant of one aspect of the invention, the turns 102, 103 intersect in at least one crossing zone. In the case illustrated in FIG. 1, the turns 102, 103 intersect in particular in the two crossing zones 109a and 109d, but in other variants, the crossing zones 109a, 109d could be more or less numerous and could be arranged differently, for example in valleys 105a, 105b, 105c, 105d, 105e, 105f or in other branches than the branches 104a, 104d, or in a following arrangement combinations of these variants. In order to facilitate the crossing of the turns 102, 103 of the inductor 101, one of the turns 102 and 103, in the example illustrated in FIG. 1, the turn 103, is composed of a succession of connected segments 103a, 103b. by means of conductive vias 1071a, 1072a, 1071d, 1072d. In other embodiments, the turn 102 could be composed of such a succession of segments, or the two turns 102, 103 could be composed of such segments. The conductive vias 1071a, 1072a, 1071d, 1072d are thus arranged in the crossing zones 109a, 109d, which in the case illustrated in FIG. 1 are the symmetrically opposite branches 104a, 104d of the inductor 101, but which, in Other preferred advantageous embodiments could be valleys, preferably symmetrically opposed valleys of a star-shaped inductance 101. In the variant with a circular geometry illustrated in FIG. 2, the two crossing zones 209a, 209d are symmetrical with respect to the geometric center of the sensor 200 or the inductor 201 and therefore diametrically opposite. In addition, according to a variant of an embodiment of the invention, as illustrated in FIG. 1, the conductive vias 1071a, 1072a, 1071d, 1072d connecting the segments 103a, 103b of the second turn 103 can be interconnected. by means of conductive traces 1081a, 1081d arranged on a second plane of the carrier substrate, parallel to the first plane but different from the latter, and are therefore essentially parallel to the turns 102, 103. At the crossing zones 109a, 109d, the Conductive traces 1081a, 1081d connecting the segments 103a, 103b of the second turn 103 by means of the conductive vias 1081a, 1081d are preferably separated from the first turn 102 and / or the second turn 103 by a dielectric medium. In this way the inductor 101 is arranged essentially on a first plane of the carrier substrate, and the electrical connections are arranged essentially on a second plane of the carrier substrate, which is substantially parallel to the first plane. The carrier substrate of the sensor 100 can then serve as a dielectric medium between the conductive traces 1081a, 1081d and the crossing zones 109a, 109d of the turns 102, 103 of the inductor 101, but it is also possible to use other materials as the carrier substrate to serve as a dielectric medium. According to another aspect of the invention, the sensor 100 of the embodiment illustrated in FIG. 1 may also comprise at least one capacitor 111, arranged on an inner periphery of the inductor 101. In other embodiments As shown in FIG. 1, a sensor according to the invention could comprise more capacitors, for example at least two or more capacitors. As illustrated in FIG. 1, the capacitor 111 may comprise two electrodes 111a, 111b arranged in two parallel planes which may be respectively the first and second planes of the carrier substrate described above, namely the plane of the turns 102, 103 of the inductance 101 and the plane of conductive traces 1081a, 1081d. The two electrodes 111a, 111b of the capacitor 111 can be connected to the terminals 106a, 106b of the inductor 101. It is then advantageous to use conductive vias 112a, 112b, 112c and conductive traces 113a, 113b, the latter being arranged preferably also on the second plane of the carrier substrate, namely the same plane as the conductive traces 1081a, 1081d of the second turn 103 of the inductor 101 and the second electrode 111b of the capacitor 111. Thus, the carrier substrate can also serve of dielectric medium between the conductive traces 113a, 113b and the turns 102, 103 of the inductor, but also of the dielectric medium between the electrodes 111a, 111b of the capacitor 111. In alternative embodiments of the present invention, it may it is possible to use a plurality of different substrates for serving on the one hand a carrier substrate to the sensor 100 and on the other hand a dielectric medium (s) between the diffs said conductive traces 1081a, 1081d or 113a, 113b and the turns 102, 103 of the inductor 101 and / or dielectric medium for the capacitor 111.

For reasons of flexibility of the sensor 100 at the time of its bending and its incorporation into a contact lens, it is advantageous that the at least one capacitor 111 has an arcuate geometry according to the geometry of the inductor 101. This aspect is illustrated in Figure 1, in which it can be seen that the capacitor 111 adopts a partially star-shaped geometry partially following the inductance 101. Similarly, in the circular geometry variants illustrated in Figures 2 and 3, the capacitor 211 respectively the capacitor 311 is in an arc according to the geometry of the inductor 201 and the inductor 301, respectively. FIG. 1 further illustrates interstices 114a, 114b, 114c which are spaces between the successive turn turns turns 102, 103 of the inductor 101. According to the invention, at least one cut-out 115a, 115b, 115c can be made in the carrier substrate in at least one of these interstices 114a, 11b 4b, 114c, for example by means of a laser or of any other equipment making it possible to operate in the dimensions and accuracies necessary for the handling of the sensor 100. The presence of at least one cut-out 115a, 115b, 115c according to FIG. The invention enables the sensor 100 to adopt a "concentric rings attached" shape which is advantageous for bending the sensor 100 for incorporation into a contact lens. At the moment of giving the spherical cap geometry to a contact lens according to the invention, that is to say provided with such a sensor 100, the cut-out (s) 115a, 115b, 115c made in the carrier substrate will give the sensor 100 improved flexibility compared to known sensors of the state of the art, which will allow a better molding with the lens. In the variant of an embodiment of the present invention illustrated in FIG. 1, three cutouts 115a, 115b, 115c are made in the carrier substrate, respectively along the interstices 114a, 114b, 114c between the turn turns of the two turns 102, 103 of the inductor 101. The presence of more than one cut 115a, 115b, 115c further improves the flexibility of the sensor 100 with respect to a single cut. However, in other variants of the invention it is possible to make only one cut, for example only one of the three cutouts 115a, 115b, 115c illustrated between the gaps 114a, 114b, 114c of the inductor 101. In still other embodiments, it is possible to combine two of the three cutouts 115a, 115b, 115c. At least one cutout is necessary according to the invention in order to make the sensor 100 more flexible for its bending and its incorporation into a contact lens. The more the sensor 100 has cutouts 115a, 115b, 115c in the interstices 114a, 114b, 114c of the inductor 101, the more the flexibility of the sensor 100 is improved compared to known sensors of the state of the art. In other variants of the present invention, it is also possible to make at least one of the cutouts 115a, 115b, 115c in segments. In such a case, it would be possible, for example, for one or a combination or all the cuts 115a, 115b, 115c as illustrated in FIG. 1 to be carried out not in one go as in FIG. , but in smaller segments. At the time of bending the sensor 100, the spaces between the segments could then tear and create the cuts 115a, 115b, 115c as illustrated in Figure 1. Such a case is illustrated in Figure 2, where the space 221 indicated in dotted line between the cutting segments 215a, 215b can tear at the time of bending the sensor 200. In another variant of the embodiment of the invention illustrated in Figure 1, it is also possible to achieve at least one other cut 116a, 116b between the at least one capacitor 111 and the inductor 101. FIG. 1 illustrates a variant in which two cutouts 116a, 116b are made in the carrier substrate along the respective gaps 117a, 117b between the capacitor 111 and turn 102. As with the cutouts 115a, 115b, 115c, the cutouts 116a, 116b further provide a concentric ring shape attached to the sensor 100, further enhancing the flexibility of the sensor. 100, thus facilitating its incorporation into a contact lens with respect to the sensors known from the state of the art. Figure 2 shows another possible variant of an embodiment of a sensor 200 according to the present invention. Many elements are identical or similar to those described in relation to FIG. 1 and, in general, the example of a sensor 200 according to an embodiment of the invention illustrated in FIG. 2 has the same advantages related to FIG. the invention that the example of a sensor 100 according to the first embodiment illustrated in Figure 1. The description of the embodiment illustrated in Figure 2 will therefore be oriented essentially around characteristics particular to this second example of a embodiment of the present invention. FIG. 2 shows a variant of an embodiment of a sensor 200 according to the invention in a planar view similar to that of FIG. 1. Thus, the sensor 200 comprises an inductor 201, which, like the inductor 101, of the previous embodiment, is essentially arranged on a first plane of a carrier substrate. The inductor 201 is of circular spiral geometry, and its smallest and largest radii, thus corresponding to the outer and inner peripheries of the double spiral described by the inductor 201, can be chosen on the basis of criteria similar to those of the dimensions of the inductor 101 of the exemplary embodiment illustrated in FIG. 1, preferably so as not to interfere with the vision of a patient carrying a lens provided with a sensor 200, particularly in the dark or in low light conditions. Like the inductor 101 of the embodiment illustrated in FIG. 1, the inductor 201 may comprise two terminals 206a, 206b situated on the largest radius of the inductor 201, that is to say on its outer periphery. . Similarly, the inductor 201 comprises a first turn 202 starting at the first terminal 206a and spiraling towards the smallest radius corresponding to the inner periphery of the inductor 201, then continuing with a second turn 203, still rotating in the same spiral direction, but from the inner periphery to the second terminal 206b located near the first terminal 206a on the outer periphery of the inductor 201. According to a variant of an aspect of the invention, the turns 202, 203 ' intersect in at least one crossing zone 209a, 209d, which, in the case illustrated in Figure 2, are in particular two in number and are further diametrically opposed. In alternative embodiments, it is possible for a sensor according to the invention to have more or less crossing zones, and for the crossing (s) to be arranged at different locations of the inductor 201, but not necessarily in such a way that diametrically opposite. An arrangement of the crossover zones 209a, 209d as in FIG. 2, and therefore diametrically opposite, is however preferred for reasons of symmetry which facilitate the bending of the sensor 200. As in the preceding example of an embodiment of the In order to facilitate the crossing of the turns 202, 203 of the inductor 201, one of the turns 202 and 203, here the turn 203, can be composed of a succession of coil segments connected by means of conductive vias. 207a, 207d and, where appropriate, conductive traces 208a, 208d. As in the embodiment illustrated in FIG. 1, in variants it could be that the turn 202 or the two turns 202, 203 are thus composed of a plurality of turn segments. For the sake of clarity of Figure 2, only a few of these conductive vias 207a, 207d and some of the conductive traces 208a, 208d are indicated with the same reference sign, but those skilled in the art will understand that each intersection between the turn 202 and the turn 203 is achieved by means of two conductive vias 207a or 207d connecting two successive segments of the turn 203 to a corresponding conductive trace 208a or 208d arranged in a second plane of the carrier substrate, which is parallel to the foreground, namely the one on which the turns 202, 203. are arranged. Thus the numerous conductive traces 208a, 208d are arranged at the respective crossing zones 209a, 209d and are preferably separated from the first turn 202 and / or segments of the second turn 203 by a dielectric medium, which may be for example, but not exclusively, the carrier substrate. In this way the inductance 201 is arranged essentially on a first plane of the carrier substrate, and the electrical connections are arranged essentially on a second plane of the carrier substrate, which is essentially parallel to the foreground, as shown in FIG. to a variant of the invention, the turns 202, 203 of the inductor 201 of the embodiment illustrated in FIG. 2 are grouped into "packets" or "series" or "rings" of turn turns 220a, 220b , 220c concentric and spaced from the next packet or ring by gaps 214a, 214b wider than the simple interstices separating two successive turns of turn within a single package or ring turn turns 220a, 220b, 220c. According to an option of this variant of an embodiment illustrated in FIG. 2, the turns 202, 203 are arranged in three rings of turn turns 220a, 220b, 220c, but other variants could comprise only one double spiral without preferential separations, that is to say a single series or a single ring of turn turns, like the variant illustrated in Figure 1. Still other variants could comprise more than three rings of turn turns 220a, 220b, 220c, by example four or five or more. The three turn ring arrangement 220a, 220b, 220c illustrated in FIG. 2 is advantageous because it provides improved flexibility to the sensor 200 over spiral geometry sensors known in the art. According to another option of the invention, each ring of turn turns 220a, 220b, 220c comprises from three to ten turns of turn. In a variant, it would therefore be possible to have, for example, three to four turn turns for the crowns or rings of turn turns 220a, 220b the outermost and for example up to ten turn turns for the turn. crown or ring of spire turns 200c the / the more inside. In the example shown in FIG. 2, the series or rings of turn turns 220a and 220b the outermost of the sensor 200 comprise five turn turns each, while the turn ring ring 220c the most center of the sensor 200 has seven turn turns. This arrangement is advantageous when bending the sensor 200, but it is also possible to use other arrangements in which the turn tower rings 220a, 220b, 220c all have different turns turn numbers or in which one of the rings 220b, 220c not being the centermost ring 220a would have more turn turns than the ring 220a the more central of the sensor 200.

According to another option of this variant, the rings of turn turns 220a, 220b, 220c are interconnected by conductive bridges 209a ', 209d', which are made by crossings between the turns 202, 203 of the inductor 201 by means of conductive traces 208a ', 208a longer than the conductive traces 208a, 208d previously described for connecting the turn segments 203 at the crossings 209a, 209d with the turn 202 within the same group of turns 220a, 220b, 220c. According to an advantageous variant of this embodiment and as illustrated in FIG. 2, the conductive bridges 209a ', 209d' can be arranged diametrically opposite on the sensor 200, in particular at the crossing zones 209a, 209d. However, it is possible not to arrange the conductive bridges 209a ', 209d' along the radii corresponding to the crossing zones 209a, 209d, but to arrange them on other radii of the sensor 200, not necessarily at 180.degree. the other. The arrangement illustrated in FIG. 2 is, however, advantageous in that the symmetry of the sensor 200 provides greater flexibility than a non-symmetrical arrangement of the conductive bridges 209a ', 209d' and / or crossover zones 209a, 209d.

It is furthermore preferable that two rings of successive turn turns, for example the rings 220a and 220b, are interconnected by a single conducting bridge 209d ', and that this conducting bridge 209d' is arranged at 180 ° of the next conducting bridge 209a ', which is the one connecting the series or the ring of turn turns 220b to the ring of turn turns 220c next. The structure of a sensor 200 according to this variant of an embodiment of the invention has the advantage of leaving a choice of interstices 214a, 214b preferential for the production of at least one cut in the carrier substrate according to the concept invention of the present application. In particular, this arrangement of groups of turn turns 220a, 220b, 220c also has the advantage of offering better flexibility when bending the sensor 200 for incorporation into a contact lens with respect to spiral geometry sensors. circular known from the state of the art. Thus, according to the invention, it is possible to make at least one cut 215a, 215b or 215c of the carrier substrate in at least one of the interstices 214a, 214b between each ring of turn turns 220a, 220b, 220c. The presence of at least one cut-out 215a, 215b, 215c gives, during the bending of the sensor 200 for incorporation into a contact lens, a form in "concentric rings attached" which offers more flexibility than the passive sensors known to the state of the art. A cut 215a, 215b, 215c suffices to provide this advantage of the invention, but a sensor 200 having more than one cut also realizes the inventive concept and offers even more flexibility than a known sensor of the state of the invention. because its concentric ring-attached structure is even more advantageous for its bending and incorporation into a contact lens. In the case illustrated in Figure 2, the at least one cut is preferably made in a gap 214a, 214b, preferably chosen between two rings of turn turns 220a, 220b, 220c. However, it would also be possible to make at least one cut in a smaller gap, between two turns of turn within the same turn ring ring 220a, 220b, 220c. Figure 2 illustrates several types of possible cuts 215a, 215b, 215c that can be combined together or taken separately. A first type of cut-out 215c is illustrated in the gap 214b between the rings 220b and 220c. Cutout 215c is made in a single stroke, in an arc following the gap 214b, however sparing the area around the conductive bridge 209a 'connecting the rings 220b and 220c. In contrast, in the gap 214a between the rings 220a and 220b, two cutting segments 215a, 215b are illustrated, with a carrier substrate bridge 221 illustrated in dotted line between the two, and still sparing an area around the conductive bridge 209d connecting the two rings 220a, 220b. Thus, it is also possible to divide the at least one cutout according to the invention into several segments 215a, 215b leaving spaces 221 between each segment 215a, 215b. Figure 2 illustrates two cuts 215a, 215b in an arc along the gap 214a, but it is possible to have more precut segments in the same gap 214a or 214b. When bending the sensor 200 for incorporation into a contact lens, the force exerted on the sensor 200 can then tear the bridge or bridges 221 carrier substrate to make a single cut along the gap 214a, apart from around the 209d partner bridge. At the time of its incorporation into a contact lens, a sensor 200 according to the invention will therefore advantageously be more flexible than a known sensor of the state of the art and therefore more suitable to adopt the spherical cap geometry of the lens of contact. According to another aspect of the invention, like the sensor 100 of the embodiment illustrated in FIG. 1, the sensor 200 of the embodiment illustrated in FIG. 2 may also comprise at least one capacitor 211 whose two electrodes 211a , 211b are connected to the terminals 206a, 206b of the inductor 201 by conductive vias 212a, 212b and conductive traces 213a, 213b playing a role similar to that of the conductive vias 112a and / or 112c and 112b and conductive traces of the mode embodiment of the embodiment illustrated in Figure 1. In order to preserve the advantageous flexibility of the structure of the conductive bridges 209a ', 209d', unlike the capacitor 111 arranged inside the sensor 100 shown in Figure 1, the capacitor 211 is arranged on an outer periphery of the sensor 200. It is always possible to use more capacitors in sensors 100, 200 according to the invention, for example in order to improve the sensitivity of said sensor. 100, 200. Apart from their arrangement outside the inductor 201, the electrodes 211a, 211b of the capacitor 211 of the second embodiment take up most of the characteristics already mentioned for the capacitor 111 of the first embodiment. that is, that their geometry follows that of the inductor 201 and that they are arranged on two parallel planes of the carrier substrate. Thus, in the embodiment illustrated in FIG. 2, the electrodes 211a, 211b are in an arc of a circle, and are preferably, but not necessarily, one, here the electrode 211a, on the same plane as the turns 202, 203, and the other, here the electrode 211b, on the plane of the conductive traces 208a, 208d, 208a ', 208d'. The carrier substrate, and optionally also other substrates, can then serve as a dielectric medium between the electrodes 211a, 211b of the capacitor 211, and / or of the dielectric medium at the crossing zones 209a, 209d and / or bridges Conductors 209a ', 209d' between conductive traces 208a, 208d, 208a ', 208d' and turns 202, 203. Figure 3 illustrates an alternative embodiment of sensor 200 shown in Figure 2. Most of elements of the sensor 300 of the embodiment illustrated in FIG. 3 are identical or similar to those of the sensor 200 of the embodiment illustrated in FIG. 2. In particular, as opposed to the essentially stellar geometry of the sensor 100 of the illustrated embodiment. in Figure 1, the geometry of the sensor 300 shown in Figure 3 is substantially circular, essentially like that of the sensor 200 shown in Figure 2. The description of the embodiment illustrated in Figure 3 will therefore be oriented essentially around features particular to this third example of an embodiment of the present invention. FIG. 3 therefore presents a variant of an embodiment of a sensor 300 according to the invention in a three-dimensional view, but nevertheless similar to that of FIG. 2. It is therefore referred to the preceding description for the details concerning the characteristics. the example embodiment shown in Figure 3 and that shown in Figure 2, as well as for details of other optional features. The essential difference between the sensor 300 of the embodiment illustrated in FIG. 3 and the sensor 200 of the embodiment illustrated in FIG. 2 is that the sensor 300 comprises an inductor 301 comprising only a single turn 302 instead of the double turn 202, 203 of the inductor 201. Thus, as illustrated in Figure 3, the first terminal 306a of the turn 302 of the inductor 301 is arranged on the largest radius of the inductor 301 and therefore on its outer periphery, but its second terminal 306b is arranged on the smallest radius of the inductor 301 and thus on its inner periphery. The inductor 301 therefore does not comprise crossing zones between two turns equivalent to the crossing zones 109a, 109d or 209a, 209d of the inductances 101, 201 of the preceding embodiments illustrated respectively in FIGS. 1 and 2. However, as in the In the above cases, the inductor 301 is arranged essentially on a first plane of the carrier substrate. and the electrical connections are arranged substantially on a second plane of the carrier substrate, which is substantially parallel to the foreground, as shown in Figure 3 and as in the previous cases. According to a variant of the invention, the turn 302 of the inductor 301 of the embodiment illustrated in FIG. 3 is divided into packets or rings or series of turn turns 320a, 320b, 320c concentric, comparable to the packets 220a, 220b, 220c of the inductor 201 illustrated in Figure 2, spaced from the next packet by interstices 314a, 314b wider than the single interstices separating two successive turns of coil within a single package or ring tow turns 320a , 320b, 320c. According to an option of this variant of an embodiment illustrated in FIG. 3, the turn 302 is arranged in three rings of turns 320a, 320b, 320c, but other variants could comprise only a simple spiral without preferential separations, that is to say a single series or a single ring of turn turns. Likewise, as in the embodiment illustrated in FIG. 2, according to another option of the invention, each ring of turns 320a, 320b, 320c of the inductor 301 of the embodiment illustrated in FIG. consist of three to ten turns of turn. In a similar way to the previous case illustrated in FIG. 2, according to another option of this variant, the turn tower rings 320a, 320b, 320c are interconnected by conductive bridges 309a ', 309 of the bridges 209a', 209d 'of the previous case, but which this time are not intersections between turns since the inductor 301 comprises only one turn 302. As in the previous case and as illustrated in FIG. Conductive bridges 309a ', 309d' can be arranged diametrically opposite on the sensor 300 but could nevertheless be arranged differently, in particular on other radii of the sensor 300, ie not necessarily at 180 ° from each other. . Thus, according to the invention and as furthermore also illustrated in FIG. 3, it is possible to produce at least one cut-out 315a, 315b of the carrier substrate in at least one of the interstices 314a, 314b between each rings of laps. turn 320a, 320b, 320c, which has the same advantages as for the previously described embodiments due to the form in "concentric rings attached" thus obtained. As for the case illustrated in FIG. 2, in the case of the sensor 300 of the embodiment shown in FIG. 3, the cuts 315a, 315b can be made in one go or in segments or they can not be realized. over the entire thickness of the carrier substrate. It is therefore referred to the previous description for more details. Thus, if at least one of the cuts 315a, 315b is made in segments or is not carried out over the entire thickness of the carrier substrate, during the bending of the sensor 300 for incorporation into a contact lens, the force exerted on the sensor 300 may then tear the carrier substrate bridge or bridges to make a single cut, if necessary, all along a gap 314a, 314b, apart around the conductor bridge 209a ', 209d' associated, or over the entire thickness of the carrier substrate. At the time of its incorporation into a contact lens, a sensor 300 according to the invention will therefore advantageously be more flexible than a known sensor of the state of the art and therefore more able to adopt the spherical cap geometry of the lens of contact.

According to another aspect of the invention, like the sensor 200 of the embodiment illustrated in FIG. 2, the sensor 300 of the embodiment illustrated in FIG. 3 can also comprise at least one capacitor 311 arranged outside. of the inductor 301 and whose two electrodes 311a, 311b are connected to the terminals 306a, 306b of the inductor 301 by the conducting vias 312a, 312b and the conductive traces 313a, 313b. In the case illustrated in FIG. 3, since the second terminal 306b is on the smallest radius of the inductor 301, it is advantageous to arrange the conductive trace 313b connecting it to the electrode 311b on the same second plane of the carrier substrate than this. FIG. 3 then illustrates an advantageous example in which the conductive trace 313b is arranged on the second plane of the carrier substrate, is of arcuate geometry and essentially follows the group of turns 320b, which is arranged on the first plane of the carrier substrate, on a turn half turn from the conductor bridge 309d 'to point 309a' where it joins the electrode 311b of the capacitor 311. Thus, as in the previous cases, the carrier substrate can also serve as a dielectric medium between the conductive traces 313a , 313b and the turn 302 of the inductor, but also dielectric medium between the electrodes 311a, 311b of the capacitor 311. Apart from the connection to the terminals 306a, 306b of the inductor 301 which is different, the capacitor 311 of the mode embodiment shown in Figure 3 essentially reproduces the characteristics already mentioned for the capacitor 211 of the second embodiment. Figures 2 and 3 further illustrate a respective cutout 222, 322 of the carrier substrate along the inner perimeter of the sensor 200, 300 and a cutout 223, 323 along the outer perimeter of the sensor 200, 300. In the illustrated cases in Figures 2 and 3, these cutouts 222, 223 and 322, 323 are circular and follow the geometry of the sensor 200, respectively the sensor 300. They could nevertheless adopt other geometric shapes. For example, similar cuts (not shown) could be made in the case of the sensor 100 of the embodiment illustrated in Figure 1 and could for example follow the essentially stellar geometry of the sensor 100. However, it is also possible that cutouts similar to the cutouts 222, 223 or 322, 323 made on the sensor 100 of the embodiment illustrated in FIG. 1 are of circular shape thus describing circles inside and outside the sensor 100, as in the case sensors 200, 300. In a variant of the embodiments of the invention illustrated in Figures 2 and 3, it would be possible, as in the embodiment illustrated in Figure 1, to achieve at least one cutout between the minus one capacitor 211, respectively 311, and the inductor 201, respectively 301, in order to further accentuate the attached concentric ring structure and thus to give even more flexibility to the sensor 200, respectively to the sensor 300. In addition, it should be noted that the at least one cut 115a, 115b, 115c, 215a, 215b, 215c, 315a, 315b or the possible combinations of cuts 115a, 115b, 115c 215a, 215b, 215c, 315a, 315b as illustrated in Figures 1-3 describing possible embodiments of the present invention do not need to be performed over the entire thickness of the carrier substrate. Indeed at the time of bending the sensor 100, 200, 300 for incorporation into a contact lens, if the sensor 100, 200, 300 comprises one or more cuts 115a, 115b, 115c, 215a, 215b, 215c, 315a, 315b made partially on the thickness of the carrier substrate, the force exerted for the bending of the sensor 100, 200, 300 can tear the cutout (s) 115a, 115b, 115c, 215a, 215b, 215c, 315a, 315b over the remainder of the thickness of the substrate, thus giving the same structure of concentric rings attached as in the case where the at least one cut is made through the entire thickness of the carrier substrate. Figures 4A and 4B illustrate an example not forming part of the present invention but which is useful for its understanding. Figure 4A shows the concept of the blanks in a substrate as detailed in particular in the embodiments described with the help of Figures 2 and 3. Figure 4B illustrates what is meant by structure in "concentric rings attached" following the realization of said cuts. Thus, Figure 4A illustrates a disk or more particularly a ring of a substrate 400, in which can be made, for example, two concentric cuts 404, 405 partial. By "partial" it is understood that the cutouts 404, 405 do not extend over an entire circumference of the ring 400 but each comprise a respective "bridge" of substrate 406, 407, an uncut segment. Figure 4A further illustrates that the blanks 404, 405 divide the substrate ring 400 into three concentric rings 401, 402, 403, which may be of variable widths depending on the rays at which the cutouts 404, 405 are made.

Figure 4B illustrates the unfolded structure 400 'resulting from the cuts 404, 405 in the substrate ring 400, namely a type of structure 400' in "concentric rings attached". As illustrated in FIG. 4B, in the structure 400 ', the substrate bridge 406 connects the rings 402 and 403, while the substrate bridge 407 connects the rings 401 and 402. It will be clear to the man of the It will be appreciated that the unfolded structure 400 as shown in FIG. 4B, including the blanks 404, 405, will be better able to adopt a spherical cap geometry than the initial substrate disk 400 prior to the making of the blanks 404, 405. Similarly, it will be clear to those skilled in the art that such a substrate ring 400 could contain a sensor 200, 300 like those of the embodiments illustrated in particular in Figures 2 or 3 or variants thereof, and therefore will the link in particular between the blank 404 and the cuts 215c or 315b, and between the blank 405 and the blanks 215a, 215b or 315a, respectively. Those skilled in the art will also make the connection between the concentric substrate rings 401, 402, 403 and the turn tower rings 220c, 220b, 220a or 320c, 320b, 320a of the embodiments illustrated in FIGS. , respectively, as well as what is meant by structure in "concentric rings attached". It will also be apparent to those skilled in the art that FIGS. 4A and 4B illustrate only one example of concentric ring-type cutouts and structures attached, and that other examples could include more or fewer cuts. and / or uncut substrate bridges that can give the unfolded structure a geometry different from that shown in Figure 4B, but nevertheless similar to it in principle. Those skilled in the art can therefore also make the link with the embodiment illustrated in Figure 1 and its variants, and therefore more generally understand the advantages of making cuts in at least one gap of the carrier substrate between two turn turns of an intraocular pressure sensor according to the present invention. Thus, it becomes evident that at the time of bending in a contact lens, the sensors 100, 200, 300 of the embodiments illustrated in FIGS. 1 to 3 can essentially adopt a geometry of the type of that illustrated in FIG. therefore advantageous compared to the known sensors of the state of the art because they allow better incorporation into a contact lens. By its various aspects, their variants and possible combinations, the invention makes it possible to solve problems related to the manufacture and use of passive sensors for monitoring physiological parameters such as intraocular pressure, in particular during bending of the sensor. for incorporation or molding with a contact lens. Indeed, a passive sensor comprising at least one cutout according to the invention can marry the spherical cap geometry of the contact lens during molding in an improved manner compared to the state of the art thanks to its advantageous ring structure concentric attached. All aspects of the invention described above can be combined to obtain more sensor variants according to the invention.

Claims (16)

REVENDICATIONS1. An intraocular pressure sensor (100, 200, 300) for incorporation into a contact lens, comprising: a carrier substrate, and an inductor (101) arranged substantially on a plane of the carrier substrate and having at least one turn (102, 103) describing a plurality of turn turns in a substantially spiral geometry, characterized in that at least one cutout (115a) of the carrier substrate is made in at least one gap (114a) between two successive turn turns of the inductor (101 ). The sensor (100, 200, 300) according to claim 1, further comprising at least one capacitor (111) with a first electrode (111a) and a second electrode (111b), characterized in that at least one one of the two electrodes (111a, 111b) of the at least one capacitor (111) is arranged on the same plane of the carrier substrate as the inductor (101). 3. Sensor (100) according to claim 2, characterized in that at least one other cutout (116a) is formed in at least one gap between said capacitor (111) and the inductor (101). 4. Sensor (100, 200) according to any one of claims 1 to 3, characterized in that the inductor (101) comprises a first turn (102) from a first terminal (106a) on the most the outside of the inductor (101) and rotating in a first spiral direction towards the innermost part of the inductor (101), and a second turn (103) extending the first turn (102) following the same spiral orientation from the innermost portion of the inductor (101) to a second terminal (106b) on the outermost portion of the inductor (101), and wherein the coil turns of the first turn (102) and the turn turns of the second turn (103) intersect in at least one crossing zone (109a, 109d). 5. Sensor (200, 300) according to any one of the preceding claims, characterized in that the inductor (201) is arranged in a plurality of concentric turn rings (220a, 220b, 220c), preferably between two and five rings of turns (220a, 220b, 220c), preferably three rings of turn turns (220a, 220b, 220c), radially spaced apart by gaps (214a, 214b) of predetermined width at least equal to or greater than the width of a gap between two turns of the turn of the same ring of turn turns (220a, 220b, 220c), and in that the at least one cutout (215a) is made at least in a gap (214a ) separating two rings of turn turns. 6. Sensor (200, 300) according to claim 5, characterized in that each ring of turn turns (220a, 220b, 220c) comprises from three to ten turn turns. 7. Sensor (200, 300) according to any one of claims 5 or 6, characterized in that the ring of turn turns (220c) most in the center of the spiral geometry of the inductor (201) comprises more turn turns than other rings of turn turns (220a, 220b). 8. Sensor (200, 300) according to any one of claims 5 to 7, characterized in that two rings of turn turns (220a, 220b) are connected to each other by at least one conductive bridge (209d '), preferably by a single conducting bridge (209d '), in particular by a single conducting bridge (209d') arranged at 180 ° of the next conductor bridge (209a ') between two rings of turn turns (220b, 220c), more particularly at crossing zones (209a, 209d). 9. Sensor (100, 200) according to any one of claims 4 to 8, characterized in that at least one of the first turn (102) and the second turn (103) is composed of a plurality of turn segments (103a, 103b) connected in the crossing areas (109a, 109d). 10. Sensor (100, 200) according to any one of claims 4 to 9, characterized in that the crossings between the first turn (102) and the second turn (103), and optionally the conductive bridges (209a '). , 209d ') between rings of turn turns (220a, 220b, 220c), are made by means of conductive vias (1071a, 1072a, 1071d, 1072d, 207a, 207d) and conductive traces (1081a, 1081d, 208a, 208d). , 208a ', 208d'). 11. Sensor (100, 200, 300) according to any one of claims 2 to 10, characterized in that each of the electrodes (111a, 111b) of the at least one condenser (111) is respectively connected to a terminal (106a). , 106b) of the inductor (101). 12. Sensor (200) according to any one of the preceding claims, characterized in that the at least one cutout (215a, 215b) is formed by successive arcuate segments (215a, 215b) leaving at least one bridge (221). of a carrier substrate between two successive cuts (215a, 215b), so that the at least one bridge (221) of the carrier substrate tears during molding of the sensor (200) for incorporation into a contact lens, where appropriate to except for crossing areas (209a, 209d) and areas around conductive bridges (209a ', 209d'). 13. Sensor (100) according to any one of the preceding claims, characterized in that the inductor (101) has a substantially stellar geometry. Sensor (100, 200, 300) according to any one of Claims 2 to 13, characterized in that the at least one capacitor (111) has an arcuate geometry that at least partially follows the geometry of the inductance (101). ). A contact lens, in particular a soft contact lens, comprising a sensor (100, 200, 300) according to any one of the preceding claims, wherein the sensor (100, 200, 300) is molded within The lens. 16. Contact lens according to claim 15, wherein the inductance (101, 201, 301) is curved perpendicularly to the first plane of the sensor according to the curvature of the lens.