Screen with integrated detector

Abstract

Title: Screen with Integrated Detector The invention relates to a measuring and display device comprising a first electrode and a second electrode, and a screen formed by a plurality of pixels, each pixel comprising at least three light-emitting diodes and control electronics. Advantageously, the first and second electrodes are transparent and arranged at least partially on the plurality of pixels. The first and second electrodes are connected to at least one control electronics for one pixel among the plurality of pixels. The invention also relates to a method for manufacturing such a device. Figure for the abstract: Fig. 13

Description

Title of the invention: Screen with integrated detector technical field

[0001] The present invention relates to the fields of optoelectronics and biomedical devices. It can be implemented for the production of so-called smart displays, equipped with display, detection, and measurement functions. Its application is particularly advantageous in the production of displays enabling biometric measurements, notably electrical measurements (electrocardiograms (ECG), bioimpedance (BioZ)) and / or optical measurements (photoplethysmography (PPG)) of physiological parameters (e.g., heart rate and its variations). PRIOR TECHNOLOGY

[0002] The continued development of smartphones, tablets and smartwatches has enabled the emergence of applications for controlling or monitoring various physiological parameters, for example heart rate.

[0003] An ECG is a test that records the heart's electrical activity to assess its function. Technological advances have made it possible to miniaturize the ECG testing device and integrate it into wearable devices, such as smartwatches. Smartwatches typically require the use of a back electrode and another electrode, usually located on the watch case. The back electrode can cause discomfort for the wearer. To ensure proper contact between the back electrode and the skin, the strap is typically tightened, which can increase discomfort for the user. Furthermore, to perform the ECG measurement, it is necessary to create an electrical conduction pathway through the heart; that is, to touch the front electrode of the watch with the other hand to establish electrical contact points on either side of the heart.More generally, there is a need to improve the ergonomics and / or make the electrodes for ECG testing as discreet as possible in a portable device.

[0004] In particular, devices such as smartphones have a large screen area and few locations for adding electrodes to the smartphone body. One solution is to add a smartphone case incorporating the electrodes. This necessitates the use of accessories. Furthermore, there is a need for the ECG test to be simple to perform, so that the user experience is satisfactory.

[0005] Other alternative or complementary tests can also be considered using these portable devices. Some devices specialize in measuring parameters Physiological devices, such as the Scanadu Scout™, offer a combination of ECG and PPG tests. These specialized devices communicate with a smartphone via a dedicated app to record and / or display test results. This requires two devices for the user, which complicates the testing process.

[0006] There is also a need for a device that is easy to use, combining in a versatile way several functions for detecting, measuring and displaying physiological parameters.

[0007] One objective of the present invention is to meet at least part of this need.

[0008] In particular, an object of the present invention is a measuring device and display allowing for the simple performance of at least one ECG test. Another object concerns a manufacturing process for such a device.

[0009] The other objects, features and advantages of the present invention will become apparent from an examination of the following description and accompanying drawings. It is understood that other advantages may be incorporated. SUMMARY

[0010] To achieve this objective, according to one embodiment, a measurement and display device is provided comprising a first electrode, a second electrode, and a screen, said screen comprising a plurality of pixels. Each pixel comprises at least three light-emitting diodes and control electronics.

[0011] Advantageously, the first and second electrodes are transparent and disposed at least in part over the plurality of pixels, and the first and second electrodes are connected to at least one control electronics of one pixel among the plurality of pixels.

[0012] Thus, the first and second electrodes are located on the emissive side of the screen. They are superimposed on the screen's pixels. The first and second electrodes are typically directly controlled by one or more pixels, via the control electronics associated with those pixels. This arrangement makes measurements easier for the user, who manipulates the screen to view the display. For example, the screen displays instructions for positioning the user's fingers or hands directly on the screen, indicating, for instance, the area of ​​the screen on which to place the fingers, and then triggers an electrical measurement via the first and second electrodes, typically to perform an ECG. The manipulation is simple and quick for the user. Grouping all the display and measurement functions on the same emissive side of the screen facilitates the use of the device.The ergonomics of the device are improved. The electrodes are... They are advantageously integrated into the screen. They do not require a specific location on the device body. Such integration is discreet and non-invasive.

[0013] According to one possibility, other detection and / or measurement functions can be added to the screen pixels. Infrared diodes and infrared photodetectors can, for example, be integrated within the pixels, under one or both of the first and second electrodes. This makes it possible to offer an "all-in-one" device capable of performing various electrical and / or optical tests directly via the device's emissive screen.

[0014] According to another aspect of the invention, a method for manufacturing a measuring and display device is provided, comprising the following steps: - To fabricate on a first substrate a plurality of control electronics, each control electronic comprising at least four first addressing pads intended to be connected with three light-emitting diodes, said first addressing pads comprising three anodes and one cathode, and two first electrical measurement pads intended to be connected with the first and second electrodes, - To form on each control electronics of the first substrate the three light-emitting diodes on the three anodes, so as to form so-called intelligent display elements having an upper face on the side of the light-emitting diodes and a lower face on the side of the control electronics, - To implement on a second substrate a plurality of pixel locations, said locations comprising four second addressing pads intended to be connected with the first addressing pads of the intelligent display elements, and two second electrical measurement pads intended to be connected with the first electrical measurement pads of the intelligent display elements, a first location among said locations comprising a first via connection area connected to one of the second electrical measurement pads and intended to be connected with the first electrode, and a second location among said locations comprising a second via connection area connected to one of the second electrical measurement pads and intended to be connected with the second electrode, - Transfer the intelligent display elements into the pixel slots, at the level of their undersides, and connect the first and second addressing pads together and the first and second electrical measurement pads together, so as to form the pixels of the display screen, - Place an encapsulation layer on and between the smart display elements, and planarize this encapsulation layer, - To form first and second openings in the encapsulation layer, respectively above the first and second via connection zones, and to fill said first and second openings with an electrically conductive material so as to form first and second vias, - Form the first and second transparent electrodes on the encapsulation layer, respectively in contact with the first and second vias, above at least some pixels of the display screen.

[0015] In this method, at least some of the pixel locations are configured to accommodate both the intelligent display elements and via connection areas for connecting the electrodes formed on the front face of the device, on the emissive side of the screen. The pixel locations can thus perform multiple functions, including display and electrical measurement functions.

[0016] This method can be advantageously implemented to produce a measuring and display device as described above. BRIEF DESCRIPTION OF THE FIGURES

[0017] The aims, objects, features and advantages of the invention will become clearer from the detailed description of embodiments thereof, which are illustrated by the following accompanying drawings in which:

[0018] [Fig.1] Fig.1 illustrates in cross-section a device according to a first embodiment of the present invention.

[0019] [Fig.2] Fig.2 illustrates in cross-section a device according to a second embodiment of the present invention.

[0020] [Fig.3] Fig.3 illustrates in cross-section a device according to a third embodiment of the present invention.

[0021] [Fig.4] The [Fig.4] illustrates in cross-section a device according to a fourth embodiment of the present invention.

[0022] [Fig.5A] [Fig.5B] Figures 5A, 5B respectively illustrate the upper and lower faces of an intelligent display element, according to an embodiment of the present invention.

[0023] [Fig.6] [Fig.7] [Fig.8] [Fig.9] [Fig. 10] [Fig. 11] [Fig. 12] Figures 6 to 12 illustrate different manufacturing stages of intelligent display elements, according to an embodiment of the present invention.

[0024] [Fig. 13] The [Fig. 13] illustrates in top view pixel locations of a second substrate, according to an embodiment of the present invention.

[0025] [Fig.14] [Fig.15] [Fig.16] [Fig.17] [Fig.18] Figures 14 to 18 illustrate different manufacturing stages of a measuring and display device, according to an embodiment of the present invention.

[0026] [Fig. 19] The [Fig. 19] illustrates in top view pixel locations of a second substrate, according to another embodiment of the present invention.

[0027] [Fig.20] [Fig.21] [Fig.22] Figures 20 to 22 illustrate different manufacturing stages of a measuring and display device, according to another embodiment of the present invention.

[0028] [Fig.23] The [Fig.23] illustrates in top view a diagram of the operation of a pixel of a measuring and display device, according to an embodiment of the present invention.

[0029] [Fig.24] The [Fig.24] illustrates in top view a screen of a measuring and display device, according to an embodiment of the present invention.

[0030] [Fig.25] The [Fig.25] illustrates in top view grouped pixel areas of a screen of a measuring and display device, according to an embodiment of the present invention.

[0031] [Fig.26] The [Fig.26] illustrates in top view a control circuit configuration of a screen of a measuring and display device, according to an embodiment of the present invention.

[0032] [Fig.27] The [Fig.27] illustrates in top view a control circuit configuration of a screen of a measuring and display device, according to another embodiment of the present invention.

[0033] The drawings are given by way of example and are not limiting of the invention. They constitute schematic representations of the principle intended to facilitate understanding of the invention and are not necessarily to scale with practical applications. In particular, in the schematic diagrams, the thicknesses of the different layers and portions, and the dimensions of the patterns are not representative of reality. DETAILED DESCRIPTION

[0034] Before proceeding with a detailed review of embodiments of the invention, optional features that may be used in combination or alternatively are listed below:

[0035] In one example, the device further comprises a transparent protective layer, for example parylene-based, on the first and second electrodes. This layer typically protects the first and second electrodes, for example, against mechanical stress or chemical (acid-base) or electrochemical reactions. In one example, the device is configured to Perform a capacitive electrical measurement via at least one of the first and second electrodes. The capacitive electrical measurement is typically made via a capacitance formed by the electrodes, the skin, and the transparent protective layer acting as a dielectric.

[0036] According to one example, the transparent protective layer has a thickness of less than or equal to 2 pm, preferably less than or equal to 1 pm. This increases the measurement sensitivity via the first and / or second electrode.

[0037] According to one example, the control electronics for each pixel are located below the at least three light-emitting diodes, and the first and second electrodes are connected locally to the at least one control electronics unit, respectively, by first and second through-hole connections or vias. The light-emitting diodes combined with dedicated control electronics typically form an intelligent display element, also called a "smart pixel".

[0038] According to one example, the plurality of pixels is arranged in the form of a matrix delimited by a contour, and the first and second transparent electrodes are disposed above the pixel matrix only within said contour. The first and second transparent electrodes cover the pixel matrix, partially or totally.

[0039] According to one example, the device is configured to display instructions for placing at least one hand on the screen, preferably two hands on the screen, and to measure a change in electrical voltage in said at least one hand via the first and second electrodes, or a change in electrical voltage between the two hands, for example, to obtain an electrocardiogram. The display and the measurement are performed on the same side of the screen and may be superimposed.

[0040] According to one example, each pixel further comprises a photodetector, for example an infrared photodetector, controlled by the control electronics of said pixel. This makes it possible, in particular, to detect the user's hand. It also makes it possible to measure a physiological parameter, for example by detecting the backscattered optical signal after interaction with the tissues of the hand, in the visible or near-infrared range.

[0041] According to one example, the device includes a function for capturing images or a set of several regions of interest, for example, resulting from pixel groupings. Each photodetector can be arranged next to or near a smart display element, within the same pixel. The device typically includes a photodetector array corresponding to the pixel array, forming an imager.

[0042] According to one example, each pixel comprises first, second, third light-emitting diodes emitting respectively first, second, third radiation in the visible spectrum, and a fourth light-emitting diode emitting a fourth radiation in the near-infrared spectrum. In one example, each pixel also includes an infrared photodetector controlled by the pixel's control electronics and configured and positioned to detect a backscattered portion of the fourth radiation. Each pixel typically comprises an infrared source and detector.

[0043] According to one example, the device is configured to display instructions for placing at least one hand on the screen and to measure a variation in the backscattered portion of the fourth radiation by said at least one hand, via at least one infrared photodetector. This typically allows for an infrared optical measurement to be performed in addition to, or instead of, the electrical measurement. Such a device allows, for example, a photoplethysmographic measurement to be performed.

[0044] According to one example, the device is configured to: - detect the presence of at least one hand via infrared photodetectors that effectively detect the backscattered portion of the fourth radiation, and for - Group the pixels containing the infrared photodetectors according to a measurement area. The device can then use only the pixels on which the hand is placed. This improves the contrast and / or the measurement of a signal of interest.

[0045] According to one example, said measurement zone is used to perform at least one measurement of a physiological parameter related to at least one hand, for example, a first heart rate measurement by electrocardiogram and a second complementary heart rate measurement by photoplethysmography. The first and / or second measurements can be taken by placing both of the user's hands on the zone.

[0046] According to one example, the pixel grouping is controlled by a plurality of programmable control blocks, each control block being located within each pixel and configured to actuate at least one row switch to connect two adjacent pixels in the same row of the screen, and at least one column switch to connect two adjacent pixels in the same column of the screen. Such grouping improves detection. In terms of application, this can be used to define regions of interest in which pixels are grouped according to certain areas of the hand. For example, pixels can be grouped for each finger to obtain a "per-finger" signal. This per-finger signal can correspond to the cumulative signal of the pixels grouped under each finger, for example from ten to twenty pixels located under each finger. The detected signal(s) can be read via an external reading circuit.

[0047] According to one example, the infrared photodetectors each produce a signal that is processed independently by each control electronics unit. According to another example, these signals are averaged so as to increase the signal-to-noise ratio.

[0048] According to one example, the process further includes the formation of a transparent protective layer, for example based on parylene, on the first and second electrodes.

[0049] In one example, each control electronics unit comprises at least one first detection pad intended to be connected to at least one photodetector, preferably an infrared photodetector. In one example, the pixel locations comprise a second detection pad intended to be connected to the first detection pad, at least some of said locations further comprising a photodetection area connected to the second detection pad, said photodetection area being intended to be connected to the control electronics of the intelligent display element. In one example, photodetectors are mounted or formed on said photodetection areas. The photodetectors are typically external to the intelligent display elements and are arranged on the second substrate.

[0050] According to one example, the photodetectors are formed by localized deposition of an organic material on the photodetection area.

[0051] According to one example, each control electronics includes at least one additional first addressing pad and the pixel locations include at least one additional second addressing pad intended to be connected with said at least one additional first addressing pad.

[0052] According to one example, the three light-emitting diodes comprise first, second, third light-emitting diodes emitting respectively first, second, third radiation in the visible range.

[0053] According to one example, a fourth light-emitting diode emitting a fourth radiation in the near-infrared range is formed on each control electronics unit and connected to at least one additional first addressing pin, so that the pixels of the display screen can emit the first, second, third, and fourth radiations and can preferably detect a backscattered portion of the fourth radiation. This makes it possible to create a device capable of performing, via its display screen, an electrical measurement and an optical measurement, for example, an electrocardiogram and a photoplethysmography measurement.

[0054] Except where incompatibility exists, it is understood that all the above optional features and / or the indicated variants may be combined to form an embodiment that is not necessarily illustrated or described. Such an embodiment is obviously not excluded from the invention. The features of one aspect of the invention, for example the device or the method, may be adapted mutatis mutandis to another aspect of the invention.

[0055] It is specified that, within the framework of the present invention, the terms "on", "overcomes", "covers", "underlying", "opposite" and their equivalents do not necessarily mean "in contact with". Thus, for example, the deposition of a first layer on a second layer does not necessarily mean that the two layers are directly in contact with each other, but means that the first layer at least partially covers the second layer by being either directly in contact with it, or by being separated from it by at least one other layer or at least one other element.

[0056] A layer may also be composed of several sub-layers of the same material or of different materials.

[0057] A substrate, stack, or layer "based" on a material A is understood to mean a substrate, stack, or layer comprising only that material A or that material A and possibly other materials, for example, alloying elements and / or dopant elements. Thus, a silicon-based substrate is understood, for example, to be a Si or doped Si substrate, or SiGe. A GaN-based layer is understood, for example, to be a GaN layer, doped GaN, or GaN alloys.

[0058] Several embodiments of the invention implementing successive steps of the manufacturing process are described below. Unless explicitly stated, the adjective "successive" does not necessarily imply, although this is generally preferred, that the steps follow each other immediately; intermediate steps may separate them.

[0059] Furthermore, the term "step" refers to the execution of a part of the process, and can designate a set of sub-steps.

[0060] Furthermore, the term "step" does not necessarily mean that the actions carried out during a step are simultaneous or immediately successive. Certain actions of a first step may, in particular, be followed by actions related to a different step, and other actions from the first step may be repeated later. Thus, the term "step" does not necessarily imply unitary actions that are inseparable in time and in the sequence of phases of the process.

[0061] In the context of the present invention, a “transparent” material means that the material allows at least 70%, preferably at least 90%, of the light intensity of the light beam passing through it to pass through.

[0062] A preferably orthonormal coordinate system, comprising the x, y, z axes, is shown in the accompanying figures. When only one coordinate system is shown on the same sheet of figures, this coordinate system applies to all the figures on that sheet.

[0063] In this patent application, the thickness of a layer is measured in a direction normal to the principal plane of extension of the layer. Thus, a layer typically has a thickness along the z-axis. The relative terms "on," "overhangs," "under," "substrate," "intercalated," "above," and "below" refer to positions measured in the z-direction. This list of terms is not exhaustive. Other relative terms may be easily specified as needed, by reference to the accompanying drawings.

[0064] The terms "vertical" and "vertically" refer to a direction along the z-axis. The terms "horizontally" and "laterally" refer to a direction in the xy plane. Unless explicitly stated otherwise, thickness, height, and depth are measured along the z-axis.

[0065] An element located "in line with" or "directly above" another element means that these two elements are both located on the same line perpendicular to a plane in which extends mainly a lower or upper face of a substrate, that is to say on the same line oriented vertically in the figures.

[0066] The present invention finds its preferred field of application in a display device comprising functions for measuring or monitoring physiological parameters, commonly called "biomonitoring".

[0067] Electrocardiogram (ECG) measurement is widely used in medicine. This ECG measurement requires two points of electrical contact on the body between which a potential difference generated by the heart can be established. The electrical path between these two points preferably passes quite directly through the heart. The ECG is generally the reference signal for providing information on heart rhythm and its variation. It is a "passive" reading of the electrical signal of heart contraction, and is therefore a "central" indicator (at the level of the heart).

[0068] Photoplethysmography (PPG) is an optical technique for measuring changes in blood volume in capillaries, arterioles, or arteries by reflecting visible and / or near-infrared light. Like ECG measurement, PPG also allows for the measurement of heart rhythm or its variations. However, PPG measurements originate from a peripheral area of ​​the heart: it is an "image" of the cardiac signal in the measurement area after the pulse wave (ejection of blood volume from the heart) has propagated through a portion of the arterial tree.

[0069] Combining the two measurements, ECG and PPG, allows for the identification of complementary physiological parameters. By measuring the time lag between the signal Using ECG and the peripheral PPG signal, it is possible, for example, to determine the pulse wave propagation time (PAT), a physiological quantity representative of a person's cardiovascular function, which is related to blood pressure. Additionally, PPG allows for the measurement of, for example, blood oxygenation.

[0070] Bioimpedance measurement is the electrical measurement of tissue resistance by sending a sinusoidal current through electrodes. It can be used to determine the amounts of water, fat and / or muscle in the tissues.

[0071] Light-emitting diodes according to the present invention typically emit monochromatic or near-monochromatic light, each wavelength having a principal wavelength. Those skilled in the art are well acquainted with the use of red, green, and blue diodes—generally referred to by the acronym RGB—in the field of display screens. An infrared (IR) diode can also be added to RGB diodes, depending on the application. The terms "light-emitting diode," "diode," "LED," "pLED," etc., are used synonymously.

[0072] The smart display element according to the invention, commonly referred to as a "smart pixel," typically comprises control electronics surmounted by RGB and / or IR diodes. This smart display element is intended to be mounted on a second substrate comprising pixel slots to form the screen of the display and measurement device according to the invention. The smart display element thus has an upper "emission" face, on the side of the RGB and / or IR diodes. The smart display element also has a lower "connection" face, on the side of the control electronics, comprising a plurality of electrical connection pads intended to be connected to the second substrate.The second substrate has a connection face with, for each pixel location, a plurality of electrical connection pads intended to be connected respectively to the electrical connection pads of the intelligent display element.

[0073] The terms "approximately", "about", "on the order of" mean "to within 10%" or, when referring to an angular orientation, "to within 10°" and preferably "to within 5°". Thus, a direction substantially normal to a plane means a direction having an angle of 90+10° with respect to the plane.

[0074] Figure 1 illustrates a first embodiment of a measurement and display device according to the invention. The display device comprises a screen formed by a plurality of pixels arranged on the corresponding pixel locations Px of the substrate 2. Each pixel here comprises an intelligent display element 20a. The intelligent display element 20a typically comprises three diodes R, G, B emitting respectively at red, green, and blue wavelengths of the visible spectrum. The smart display element 20a also includes control electronics 10 connected to diodes R, G, and B and configured to control diodes R, G, and B. The smart display element 20a is connected to substrate 2 in pixel location Px of said pixel via the control electronics 10. The control electronics 10 may, for example, include MOS transistors.

[0075] The pixels are encapsulated in an encapsulation layer 230. This encapsulation layer 230 serves, in particular, to planarize the entire structure. It is not necessarily airtight. The encapsulation layer 230 can be described as a planarization layer. A first electrode 31 and a second electrode 32 are arranged on said layer 230. The first and second electrodes 31, 32 are transparent, particularly in the visible and near-infrared or infrared spectrum. The first and second electrodes 31, 32 can be based on a conductive oxide, for example, based on an indium-tin alloy oxide (ITO, acronym for "Tin Indium Oxide"). The first electrode 31 is typically connected to a control electronics 10 of a smart display element 20a by a vertical connection 21 called a through-hole or via.The connection between the via 21 and the control electronics 10 can be made via a metal trace on the substrate 2. Similarly, the second electrode 32 is connected to the control electronics 10 of a smart display element 20a by a via 22. The control electronics 10 are typically based on complementary MOS transistor (CMOS) technology and conventionally comprise transistors interconnected by different metal layers. The control electronics 10 connected to the first and second electrodes 31, 32 are preferably separate. However, a single control electronics 10 connected to both the first and second electrodes 31, 32 can also be used. The first and second electrodes 31, 32 extend over the pixels of the DI device's display. Each electrode 31, 32 typically extends over several pixels.Each electrode 31, 32 can have a surface area of ​​a few hundred mm2 to a few cm2, for example on the order of 1 cm2.

[0076] A protective layer 40, for example made of parylene or glass, can be applied to the first and second electrodes 31, 32. This protective layer 40 preferably has a relatively small thickness, for example between 1 µm and 10 µm, on the order of 2 µm to 5 µm. This improves the sensitivity of a capacitive measurement using the first and / or second electrodes 31, 32. The protective layer 40 allows the user to touch the screen to perform capacitive electrical measurements without damaging the first and second electrodes 31, 32.

[0077] Figure 2 illustrates a second embodiment of a measuring and display device D2 according to the invention. The device D2 comprises, as before, a screen formed by a plurality of pixels in the locations Px. Each pixel here comprises a smart display element 20b and a photodetector 23. The smart display element 20b typically comprises three diodes R, G, B as before, and an IR diode emitting at one or more near-infrared wavelengths. The photodetector 23 is connected to the control electronics 10 of the smart display element 20b. The control electronics 10 typically allows the photodetector 23 to be controlled, for example, for capturing or reading a detection signal. The photodetector 23 is typically configured to detect infrared radiation, for example infrared radiation from the IR diode and backscattered by a finger or hand located above the photodetector 23.The photodetector 23 is located on the substrate 2, next to the intelligent display element 20b. The display of device D2 thus combines capacitive electrical measurement functions via the first and / or second electrodes 31, 32, and near-infrared optical measurement via the IR diodes and the IR photodetectors 23. Device D2 can, for example, perform an ECG measurement and a PPG measurement, sequentially or simultaneously.

[0078] The intelligent display element 20b includes, as before, control electronics 10 connected here to the diodes R, G, B, IR and configured to control the diodes R, G, B, IR. As before, the pixels are encapsulated in an encapsulation layer 230 on which the first and second electrodes 31, 32 are arranged. A protective layer 40 may also be arranged on the first and second electrodes 31, 32.

[0079] Figure 3 illustrates a third embodiment of a measurement and display device D3 according to the invention. The device D3 comprises, as before, a screen formed by a plurality of pixels in the locations Px. Each pixel here comprises an intelligent display element 20a, and some pixels further comprise an IR diode located away from the intelligent display element 20a, and a photodetector 23. It is not necessary for all pixels to have IR detection functions. This reduces the cost of the device D3. The IR diode can be controlled by a control electronics 10 of an intelligent display element 20a, or by dedicated electronics, for example integrated into the substrate 2. The device D3 can comprise the same elements (encapsulation layer, electrodes, protective layer) as before.

[0080] Figure 4 illustrates a fourth embodiment of a measuring and display device D4 according to the invention. The device D4 comprises, as before, a screen formed by a plurality of pixels in the locations Px. Each pixel includes here an intelligent display element 20c, and photodetectors 231, 232, 233.

[0081] The intelligent display element 20c typically comprises three R, G, B diodes as before, and three IR1, IR2, IR3 diodes emitting at different near-infrared wavelengths. The photodetectors 231, 232, 233 are typically configured to detect infrared radiation emitted respectively from the IR1, IR2, IR3 diodes and backscattered by a finger or hand located above said photodetectors 231, 232, 233. According to another possibility, the photodetectors 231, 232, 233 are configured to detect radiation in the spectral ranges defined between 525 nm and 550 nm (visible green), between 630 nm and 660 nm (visible red), and between 730 nm and 940 nm (red IR). These radiations can originate from diodes R, G, B and / or diodes IR1, IR2, IR3, and be backscattered by the user's finger or hand. The D4 device's screen thus exhibits multispectral detection capabilities.This allows, for example, the probing of different depths of the user's skin. The absorption of radiation by the skin's components depends, in particular, on the wavelength of that radiation. The area probed will typically be more superficial in the visible spectrum than in the near-infrared.

[0082] The intelligent display element 20c includes, as before, control electronics 10 connected here to diodes R, G, B, IR1, IR2, IR3 and configured to control diodes R, G, B, IR1, IR2, IR3 and photodetectors 231, 232, 233. The device D4 may include the same elements (encapsulation layer, electrodes, protection layer) as before.

[0083] Figures 5A, 5B illustrate a smart display element 20a comprising three R, G, B diodes. The R, G, B diodes are arranged on the control electronics 10 and form an emitting face corresponding to the upper face 101 of the intelligent display element 20a ([Fig. 5A]). The intelligent display element 20a has a lower face 102 opposite the upper face 101. The lower face 102 corresponds to a face of the control electronics 10 and includes the first four addressing pads 81, 82, 83, 84 connected to the R, G, B LEDs via the connection ranges (e.g., three anodes and one cathode for the R, G, B diodes) of the control electronics 10.

[0084] The lower face 102 also includes here two first electrical measuring pads 85, 86 intended to be connected with the first and / or second electrode 31,32.

[0085] The number of pads on the lower face 102 of the control electronics 10 and / or on the substrate 2 may vary depending on the different functions assigned to these pads, and depending on the control architecture chosen (serialization or other). The plots are illustrated in the figures as examples, without this being limiting or necessarily representative of the exact number of plots.

[0086] Figures 6 to 12 illustrate certain steps in the realization of intelligent display elements or smart pixels.

[0087] As illustrated in [Fig. 6], a first substrate 1 comprising the control electronics and their connection pads (Al, A2 anodes and K cathodes shown here) is provided. This first substrate 1 can be of the silicon-on-insulator (SOI) type, comprising a bulk silicon support (BULK), a buried oxide layer (BOX), and a surface silicon layer (topSi). The control electronics (not visible in the figure) are typically formed on the topSi. The first addressing and measurement pads are also formed on the topSi, in connection with the control electronics. The formation of substrate 1 is well known to those skilled in the art and is not detailed for the sake of brevity.

[0088] A substrate O comprising a stack of optically active layers 51 on a support 50 is also provided. The stack of optically active layers 51 may include various sublayers forming, for example, quantum multi-wells and carrier injection layers on either side of the quantum multi-wells. It may be GaN-based. The support 50 typically corresponds to a substrate on which the stack of optically active layers 51 is formed by epitaxy. The support 50 may be sapphire- or silicon-based. The formation of the substrate O is well known to those skilled in the art and is not detailed for the sake of brevity. The substrates 1, O are assembled here by bonding, typically by molecular bonding, or by thermocompression via two metal layers 111, 112.

[0089] As illustrated in [Fig.7], after bonding, the stack of optically active layers 51 is attached to the first substrate 1 via a metallic layer 110 formed by the layers 111, 112. The support 50 is then removed, for example by trimming, so as to expose the stack of optically active layers 51.

[0090] As illustrated in [Fig.8], the first light-emitting diodes 60 are defined by lithography and etching of the stack of optically active layers 51. The first light-emitting diodes 60 are thus formed on the anodes Al, A2, A3 of the control electronics.

[0091] As illustrated in [Fig. 9], the sides of the first light-emitting diodes 60 are then passivated by a passivation layer 61. A metal layer 62 is then deposited between the first passivated light-emitting diodes 60. This allows electrical contact between the cathodes K. The surface 602 is then planarized so as to expose the upper carrier injection layers of the first light-emitting diodes 60.

[0092] As illustrated in [Fig. 10], a transparent conductive layer 63, for example based on ITO, is then deposited on the planarized surface 602. This allows the first LEDs 60 to be electrically connected to the cathodes K, which are common to the LEDs 60. Color converters 64, 65, typically converting UV or blue radiation from the first LEDs 60 into green and red radiation respectively, are then formed on the first LEDs 60 to obtain the R, G LEDs. The B LED (not shown) can be formed directly from a single LED 60, without a color converter. LEDs or pLEDs R, G, B, along with their control electronics, are thus obtained.

[0093] As illustrated in [Fig.1 1], the substrate 1 carrying the LEDs R, G, B is then assembled to a manipulation substrate 3, then the BULK support of the substrate 1 is removed, for example by trimming with a stop on the BOX of the substrate 1. Connections 71, 72, 73, 74, 75 are formed through the BOX to the metal levels of the control electronics in the topSi.

[0094] As illustrated in [Fig. 12], pads 81, 82, 83, 84, 85 are then formed on the various connections 71, 72, 73, 74, 75 for future connection in the pixel locations of a second substrate. The pads 81, 82, 83, 84, 85 can correspond to bumps, indium-based solder points, or even microtubes or other similar features. The diode groups R, G, B and their control electronics are then separated from each other by trenches 800 to form the intelligent display elements. The trenches 800 can be formed by plasma etching or plasma cutting. Individualized intelligent display elements on a manipulation substrate 3 are thus obtained.

[0095] Figure 13 illustrates, in a top view, two adjacent pixel locations Pxl, Px2 of a second substrate 2, according to a first embodiment of a DI device. The pixel locations Pxl, Px2 each include, in particular, a receiving area S for a smart display element. The receiving area S typically comprises four secondary addressing pads 91, 92, 93, 94 intended to receive the first addressing pads 81, 82, 83, 84 of the smart display element, and two secondary electrical measurement pads 95, 96 intended to receive the first electrical measurement pads 85, 86 of the smart display element. Again, the number of pads shown is not necessarily representative of the number of pads in the actual architecture.

[0096] The addressing pads 91, 92, 93, 94 and the measuring pads 95, 96 can be connected to different metallic rows L1, L2 and columns C1, C2, C3 of a control and / or readout circuit formed on the substrate 2. The different rows L1, L2 and columns C1, C2, C3 can be serialized. For example, columns C1, C2, C3 These can be assigned respectively to the power supply (Vdd), the display data (data RGB), and the measurement data (data mes). The L1 and L2 lines can be assigned respectively to the display control (select RGB) and the measurement control (select mes).

[0097] In this example, the addressing pads 91 are connected to the L1 rows; the addressing pads 92 are connected to the L2 rows; the addressing pads 93 are connected to the C1 columns; the addressing pads 94 are connected to the C2 columns; and the measurement pads 96 are connected to the C3 columns. Some measurement pads 95, for example here in pixel location Px1, are connected to a via area 200 intended to receive a through-via connected to the first or second electrode of the device. Only certain pixel locations, for example one pixel location per 1 mm² screen area, are configured to receive a through-via. The pixel location Px2 shown here is not configured to receive a through-via. The substrate 2 can be made of glass, or based on a flexible material, and may include TFT thin-film transistors for the control and / or readout circuitry.

[0098] Figures 14 to 18 illustrate certain steps in the realization of the measuring and display device according to the invention.

[0099] As illustrated in [Fig. 14], the manipulation substrate 3 carrying the smart display elements 20a is brought into contact with the second substrate 2. Some of the smart display elements 20a are transferred to pixel locations Px of the substrate 2, for example, by mass transfer techniques. The various pads 81, 82, 83, 84, 85, 86 of the smart display elements 20a are connected to the corresponding pads 91, 92, 93, 94, 95, 96 in the receiving areas of the pixel locations Px. The connection is made by pressure and / or the application of heat, for example, by heat compression or brazing. The smart display elements 20a are then detached from the manipulation substrate 3. Typically, only a portion of the smart display elements 20a are transferred to the substrate 2.The pixel location array spacing (Px) generally differs from the array spacing used to form the intelligent display elements (20a). Multiple passes can be performed with the manipulation substrate (3) to populate all the pixel locations (Px) of the screen.

[0100] As illustrated in [Fig. 15], an encapsulation layer 230 is then deposited on and between the intelligent display elements 20a. This encapsulation layer 230 can be based on a transparent polymer material. It can be deposited by centrifugation.

[0101] As illustrated in [Fig.16], an opening of via 240 is made vertically above each zone of via 200, for example in a conventional way by lithography and engraving. Optionally, the encapsulation layer 230 can be based on a photosensitive material. In this case, opening via 240 does not require etching.

[0102] As illustrated in [Fig. 17], the via openings are then filled with an electrically conductive material, typically a metal, to form the vias 21. The electrodes 31, 32 are then formed on the encapsulation layer 230 and on the corresponding vias 21. The transparent electrodes 31, 32 are typically formed by deposition and structuring of an ITO layer. According to one possibility, the vias 21 and the electrodes 31, 32 are formed simultaneously by deposition of the same transparent electrically conductive material.

[0103] As illustrated in [Fig.18], a protective layer 40 is preferably formed on the electrodes 31, 32. This protective layer 40 can be formed by depositing a glass cap, or by depositing a layer of parylene, or even by multilayer deposition.

[0104] Figure 19 illustrates in top view two adjacent pixel locations Pxl', Px2' of a second substrate 2, according to a second embodiment of a device D2. In this second embodiment, the pixel locations Pxl', Px2' each include in particular an area 203 for receiving an infrared photodetector 23. The pixel locations Pxl', Px2' also each include a receiving area S for a smart display element. The receiving area S typically includes here four second addressing pads 91, 92, 93, 94 intended to receive the first addressing pads 81, 82, 83, 84 of the intelligent display element, two second electrical measurement pads 95, 96 intended to receive the first electrical measurement pads 85, 86 of the intelligent display element, and a photodetector pad 97 intended to receive a corresponding pad of the intelligent display element.Again, the number of blocks shown is not necessarily representative of the number of blocks in the actual architecture.

[0105] Addressing pins 91, 92, 93, 94 and measurement pins 95, 96 can be connected to different metallic rows L1, L2 and columns C1, C2, C3 of a control and / or readout circuit formed on substrate 2. The different rows L1, L2 and columns C1, C2, C3 can be serialized, as before. Columns C1, C2, C3 can be assigned respectively to the power supply (Vdd), display data (data RGB), and measurement data (data mes). Rows L1, L2 can be assigned respectively to the display control (select RGB) and the measurement control (select mes).

[0106] In this example, the addressing blocks 91 are connected to rows L1; addressing blocks 92 are connected to rows L2; ​​addressing blocks 93 are connected to columns C1; addressing blocks 94 are connected to columns C2; measurement blocks 96 are connected to columns C3. Blocks 97 are connected to the photodetector zones 203. Some measurement pads 95, for example here in pixel location Pxl', are connected to a via zone 200 intended to receive a through-via connected to the first or second electrode of the device. As before, only certain pixel locations, for example one pixel location per 1 mm² screen area, are configured to receive a through-via. Pixel location Px2' shown here is not configured to receive a through-via. The substrate 2 can be made of glass, or based on a flexible material, and include TFT thin-film transistors for the control and / or readout circuitry. The number of pads in the receiving zone S can vary, depending on the type of smart display element to be placed in the corresponding pixel location.The number of pins in the receiving area S may also depend on the serialization options chosen for the control and / or reading circuit.

[0107] Figures 20 to 22 illustrate certain steps in the realization of the measuring and display device according to the second embodiment of the invention.

[0108] As illustrated in [Fig. 20], preferably after transfer of the intelligent display elements 20b, photodetectors 23 are formed on the areas 203 of the pixel locations Px'. The photodetectors 23 can be formed in a known manner by localized deposition of an organic layer ensuring the IR photodetection function.

[0109] As illustrated in [Fig. 21], a transparent electrode 33, for example based on ITO, is deposited on the photodetectors 23. The deposition can be carried out through a masking grid commonly called a "shadow mask". A thin inorganic film 300, for example based on Al2O3 or SiO2, is preferably deposited on the organic layers forming the photodetectors 23 and the electrodes 33, to protect them.

[0110] As illustrated in [Fig. 22], an encapsulation layer 230 is then deposited on and between the smart display elements 20b, and on the photodetectors 23. As before, this encapsulation layer 230 can be based on a transparent polymer material. It can be deposited by centrifugation.

[0111] The subsequent manufacturing steps of the D2 device (opening of the vias, filling of the vias and formation of the electrodes, protective cover) are typically carried out as before, as illustrated in figures 16 to 18 (cross-sectional views passing through via areas).

[0112] Figure 23 details the control blocks associated with a pixel according to the invention. Each pixel contains the circuits that control the pLEDs for display and reading from sensors (electrodes and / or photodetectors). A combination of switches Sxi, SxO, Syi, SyO within each pixel allows for connection to In parallel, a random number of sensors are placed on selected areas. Depending on one possibility, the control of the LEDs, switches, and the reading are serialized on a single DATA column. An example of such a shift register-based configuration can be found in document US2023 / 0056511 A1.

[0113] A DD control block controls each R, G, B, IR pLED individually. The refresh mode for forming the image, which can be analog or digital (PWM), is known to those skilled in the art. This DD control block is typically slaved to a 600 controller configured to control both the display, the switches, and the sensor readings.

[0114] The 600 controller is addressed by the CTRLX column and the CTRLY row. It receives the data for the display via the DATA column. It selects the programming mode (LED or switches) via the LED / SW row. The 600 controller is typically based on combinational and sequential logic, preferably serially programmable.

[0115] The Sxi, SxO, Syi, and SyO switches are controlled by the 600 controller. This allows each of the Sxi, SxO, Syi, and SyO switches to be opened or closed according to the desired configuration. The SY rows and SX columns are interrupted at each pixel to allow for individual connections.

[0116] The reading of the sensor section 200, 23 is performed via a dedicated circuit block RD. This circuit block RD typically includes an ELECTRODE readout circuit connected to the via 200 area via a Sri switch. The ELECTRODE readout circuit may include a follower amplifier or a simple short circuit. It connects the via 200 area to the VX column via an SRoI switch.

[0117] The circuit block RD also includes a PHOTODIODE readout circuit connected to the photodetector 23 via an Srp switch. The PHOTODIODE readout circuit connects the photodetector 23 to the VX column via an SRoP switch or by a simple short circuit.

[0118] The Sri, Srp, SRoI, SRoP switches are controlled by the controller 600. Connecting all the photodetectors 23 in parallel via these switches allows a reduction in the associated impedance.

[0119] As illustrated in [Fig. 24], the circuits described above advantageously allow the reading of an ECG electrical signal from two ITO electrodes 31, 32. The signal is read at the column base by configuring each of the pixels Px in parallel via the switches Sri. The signal can be read by a single ECG RD circuit configured for amplification and digital conversion of the signal using one of the methods known to those skilled in the art. For clarity, only the Vx connection is shown in [Fig. 24]. The ECG RD circuit It can be integrated into the column circuit or implemented in a separate circuit. When the ITO electrodes 31 and 32 are protected by a dielectric material layer, the ECG signal is capacitively coupled to the ECG RD readout circuit. This prevents current flow into the body and saturation of the ECG RD circuit's input amplifier due to an excessive signal level.

[0120] According to a possibility illustrated in [Fig. 25], zoning by pixel grouping can be performed. This pixel grouping can be carried out for the photodetectors and / or for the electrodes 31, 32. In the latter case, from a material point of view, a plurality of electrodes 31, 32 cover the pixels Px of the device's screen. Each pixel can be connected by a via to its own electrode. Several pixels can also share the same electrode.

[0121] By combining switches Sxi, SxO, Syi, SyO, it is possible to select specific groups of photodetectors or electrodes. In particular, the sensors (photodetectors or electrodes) are connected in parallel to form two groups Gl, G2 on two separate column areas. In the case where two or more groups coexist on the same column Vx, an additional amplification stage of the TIA (Trans-Impedance Amplifier) ​​type can be integrated into the circuit block RD of each pixel. These circuit configurations are known to those skilled in the art.

[0122] The signal reading from the photodiodes or electrodes can be averaged within each group Gl, G2, to improve the signal-to-noise ratio. The selected photodiode or electrode groups can advantageously correspond to the user's finger or hand positions on the screen. This improves signal collection. In one option, the display screen can indicate the two sensitive areas, corresponding to groups Gl, G2, where the two fingers should be placed to perform an ECG and / or PPG test.

[0123] Pixel grouping can be performed after an initial phase of detecting the user's fingers or hands. Typically, the photodetectors of each pixel determine whether or not fingers or hands are present above the corresponding pixel. Grouping is then performed only for pixels that collect a signal, without any prior assumptions about the position of the hands or fingers. Only the pixels opposite which the hands are placed contribute to the ECG and / or PPG measurements. This improves the signal-to-noise ratio, enhancing ergonomics and the user experience. ECG and / or PPG tests are made easier for the user. Signal models can be stored and / or signal comparisons can be performed to improve the accuracy and reliability of finger or hand detection. This allows, for example, the detection of different hand sizes, different contact pressures with the screen, etc.

[0124] Figure 26 illustrates a classic configuration for the arrangement of the various H, V control circuits for the rows and columns of pixels of the screen. The H, V control circuits are here placed outside the substrate and connected by ribbon cables as illustrated in Figure 26.

[0125] Figure 27 illustrates another implementation configuration comprising individual COG (Circuit On Glass) type circuits per row and per column directly soldered onto the substrate. In this case, a single general control circuit is placed outside and connected by a single ribbon cable, as illustrated in Figure 27.

[0126] From the foregoing, it is clear that the present invention advantageously enables the implementation of a measurement and display device combining electrical and / or optical tests in a user-friendly manner. The tests are performed directly via the device's display screen. This makes it easier, for example, to provide hand placement instructions when the user is performing an ECG and / or PPG test.

[0127] The invention is not limited to the embodiments described above. Other measurements, for example with four electrodes, can be considered based on the principle of the present invention. Bioimpedance measurements, in particular, can be considered.

Claims

1. Demands A measuring and display device (D1, D2, D3, D4) comprising a first electrode (31) and a second electrode (32), and a screen formed by a plurality of pixels (Px), each pixel comprising at least three light-emitting diodes (R, G, B) and control electronics (10), in which: • the first and second electrodes (31, 32) are transparent and arranged at least partially on the plurality of pixels (Px), and said first and second electrodes (31, 32) are connected to at least one control electronics (10) of one pixel (Px) among the plurality of pixels, • each pixel (Px) comprises first, second, third light-emitting diodes (R, G, B) emitting respectively first, second, third radiations in the visible range, and a fourth light-emitting diode (IR) emitting a fourth radiation in the near-infrared range, and each pixel further comprises a photodetector (23) called infrared controlled by the control electronics (10) of said pixel and configured and arranged so as to detect a backscattered part of the fourth radiation, the device being configured for: • display instructions for placing at least one hand on the screen, and • measure a variation in the backscattered portion of the fourth radiation by said at least one hand, via at least one infrared photodetector (23), and • detect the presence of at least one hand via infrared photodetectors (23) effectively detecting the backscattered portion of the fourth radiation, and • group the pixels (Px) comprising said infrared photodetectors according to a measurement zone (G1, G2), said measurement zone (G1, G2) being used to perform at least one measurement of a physiological parameter related to at least one hand, for example a first measurement of heart rate by electrocardiogram and a second complementary measurement of heart rate by photoplethysmography • the device being characterized in that the grouping of pixels is controlled by a plurality of programmable control blocks (600), each control block being disposed within each pixel (Px) and configured to actuate at least one row switch (Syi, SyO) allowing to connect two adjacent pixels of the same row of the screen, and at least one column switch (Sxi, SxO) allowing to connect two adjacent pixels of the same column of the screen.

2. Device according to the preceding claim further comprising a transparent protective layer (40), for example based on parylene, on the first and second electrodes (31, 32), said device being configured to perform a capacitive electrical measurement via at least one of the first and second electrodes.

3. Device according to the preceding claim in which the transparent protective layer (40) has a thickness less than or equal to 2 pm, preferably less than or equal to 1 pm.

4. Device according to any one of the preceding claims wherein the control electronics (10) of each pixel (Px) is located below the at least three light-emitting diodes (R, G, B), and wherein the first and second electrodes (31, 32) are locally connected to the at least one control electronics (10) respectively by first and second through connections (21, 22) or vias.

5. Device according to any one of the preceding claims wherein the plurality of pixels (Px) is arranged in the form of a matrix delimited by a contour, and wherein the first and second transparent electrodes (31, 32) are arranged above the pixel matrix only inside said contour.

6. A device according to any one of the preceding claims configured to display placement instructions for at least one hand on the screen, and to measure a variation of electrical voltage of said at least one hand by the first and second electrodes (31, 32), for example to obtain an electrocardiogram.

7. Device according to any one of the preceding claims wherein each pixel (Px) further comprises a photodetector (23), for example an infrared photodetector, controlled by the control electronics (10) of said pixel.

8. Device according to any one of the preceding claims wherein the infrared photodetectors (23) each produce a signal that is independently processed by each control electronics (10), said signals being averaged so as to increase a signal-to-noise ratio.

9. A method for manufacturing a measuring and display device according to any one of the preceding claims, comprising: • Implementing on a first substrate (1) a plurality of control electronics, each control electronic comprising at least four first addressing pads (81, 82, 83, 84) intended to be connected with three light-emitting diodes (R, G, B), said first addressing pads comprising three anodes and one cathode, and two first electrical measurement pads (85, 86) intended to be connected with the first and second electrodes (31, 32), • Forming on each control electronic (10) of the first substrate (1) the three light-emitting diodes (R, G, B) on the three anodes, so as to form so-called intelligent display elements (20a, 20b) having an upper face on the side of the light-emitting diodes (R, G, B) and a lower face on the side of control electronics,• Implement on a second substrate (2) a plurality of pixel locations (Px, Px', Pxl, Pxl', Px2, Px2'), said locations comprising four second addressing pads (91, 92, 93, 94) intended to be connected with the first addressing pads (81, 82, 83, 84) of the intelligent display elements (20a, 20b), and two second electrical measurement pads (95, 96) intended to be connected,

10.

11. with the first electrical measurement points (85, 86) of the intelligent display elements (20a, 20b), a first location (Pxl, Pxl') among said locations comprising a first via connection area (200) connected to one of the second electrical measurement pads (95) and intended to be connected with the first electrode (31), and a second location among said locations comprising a second via connection area connected to one of the second electrical measurement pads and intended to be connected with the second electrode (32), • Transfer the intelligent display elements (20a, 20b) into the pixel slots, at their lower faces, and connect the first and second addressing pads together and the first and second electrical measurement pads together, so as to form the pixels of the display screen, • Place an encapsulation layer (230) on and between the smart display elements (20a, 20b), and planarize this encapsulation layer (230), • Form first and second openings (240) in the encapsulation layer (230), respectively above the first and second connection zones (200) of vias, and fill said first and second openings with an electrically conductive material so as to form first and second vias (21, 22), • Form the first and second transparent electrodes (31, 32) on the encapsulation layer (230), respectively in contact with the first and second vias (21, 22), above at least some pixels of the display screen. A method according to the preceding claim further comprising the formation of a transparent protective layer (40), for example based on parylene, on the first and second electrodes (31, 32). A method according to any one of the two preceding claims, wherein each control electronics unit comprises at least one first detection pad intended to be connected with at least one photodetector (23), preferably an infrared photodetector. in which the pixel locations (Pxl', Px2') include a second detection pad (97) intended to be connected with the first detection pad, at least some of said locations further including a photodetection area (203) connected to the second detection pad (97), said photodetection area being intended to be connected with the control electronics of the intelligent display element (23b), and in which photodetectors (23) are transferred or formed on said photodetection areas (203).

12. Method according to the preceding claim wherein the photodetectors (23) are formed by localized deposition of an organic material on the photodetection zone (203).

13. A method according to any one of the two preceding claims, wherein each control electronics unit comprises at least one additional first addressing pad and the pixel locations comprise at least one additional second addressing pad for connection with said at least one additional first addressing pad, wherein the three light-emitting diodes comprise first, second, and third light-emitting diodes (R, G, B) emitting first, second, and third radiation respectively in the visible range, and wherein a fourth light-emitting diode (IR) emitting fourth radiation in the near-infrared range is formed on each control electronics unit and connected to at least one additional first addressing pad, so that the pixels of the display screen can emit the first, second, and thirdand fourth radiation, and preferably detect a backscattered portion of the fourth radiation.

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