Proximity sensing indicator element

Abstract

A proximity sensing display element (1) is provided, including a light guide (10), at least one light emitting element (30), and at least one infrared radiation sensor (40). The light guide (10) comprises a substrate (11) having first and second opposite major sides (12, 14) with first and second reflective layers (22, 24), respectively, the first and second reflective layers (22, 24) having reflective inner surfaces (222, 242) facing the inside of the light guide. At least one window (16) is provided in the first major side to allow optical radiation to enter and exit the light guide. At least one light emitting element (30) is typically embedded in the substrate at its second major side to generate optical radiation within the light guide. At least one IR sensor (40) is disposed on the second major side of the substrate and faces the first major side through a semi-transparent patch (240) in the second reflective layer (24). [Selected Figure] Figure 1

Description

[Technical Field]

[0001] This invention relates to a proximity sensing display element. [Background technology]

[0002] International Publication No. 2015 / 049425 discloses a proximity-sensing indicator element used as a composite laminate assembly for electronic devices. This assembly provides integrated backlighting for one or more indicator shapes defined by the assembly. The assembly includes a substantially opaque cover member that covers at least a portion of the electronic device. Translucent indicator structures within the cover member define the shape of each indicator so that backlight passes through the cover member. An optical matrix layer of photoconductive material is mounted on the inner surface of the cover member, and one or more lighting devices are embedded in the optical matrix layer and offset laterally from the associated indicator structures. The multiple lighting devices may be connected to an electrical circuit mounted on the inner surface of the cover member.

[0003] The above-mentioned document further discloses control elements formed by capacitive buttons. These elements enable capacitive proximity sensing of the user's finger when the user's finger is pressed against the outer surface of the cover member, allowing the user to input.

[0004] The drawing shows that the control element formed by the capacitive button is located outside the transparent optical element that defines the indicator window with the indicator structure. For more intuitive control, it is desirable that the control element coincides with the indicator structure. In this way, the user can easily associate a specific control element with a specific function of the controlled object. However, this means that, for known devices, the capacitive element and / or the wires to it obscure the indicator structure within the indicator window. [Prior art documents] [Patent Documents]

[0005] [Patent Document 1] International Publication No. 2015 / 049425 [Overview of the project] [Problems that the invention aims to solve]

[0006] Therefore, the objective is to provide an improved indicator structure that allows for the identification of human interaction associated with the indicator window without the need to provide control elements or obscure the indicator structure within the indicator window. [Means for solving the problem]

[0007] This provides the indicator structure described in claim 1.

[0008] As a countermeasure to be claimed, an optical sensor inside the light guide path is provided.

[0009] The IR sensor is positioned in front of the window, thereby providing good sensitivity to human contact or approach. The sensor, located on the second main side of the substrate, does not obscure the indicator structure within the indicator window located on the first main side opposite the second main side. Nevertheless, a diffuser may be optionally placed within the indicator window to adjust the brightness and / or uniformity of the illuminated indicator structure. The response is selective because the transmission of light radiation into the light guide path is limited to the window facing the IR sensor; that is, infrared radiation outside the window boundary is not transmitted towards the sensor (or is insufficiently strong in comparison). When this sensor is used for proximity sensing, its sensitivity is limited to the aperture angle defined by the window and the distance between the window and the sensor. Thus, the window serves two purposes: determining the light distribution that defines the icon and determining the spatial angle at which the sensor is sensitive. The high sensitivity of this sensor is achieved by its positioning in front of the window. The translucent patch of the second reflective layer (partially) conceals the sensor, so that the sensor in this preferred configuration is not visible through the window, but responds appropriately to sufficient IR radiation received through the translucent patch as a result of a person approaching or touching the window. Furthermore, the sensitivity of this sensor can be adjusted by the properties of the translucent patch, e.g., by selecting the transparency of the material used, or, if the patch is provided as a grid, by the aperture within the grid. Instead of having a sensor that responds to mid-infrared (M-IR) radiation corresponding to the wavelength range of radiation emitted by the human body, it is also possible to have one or more sensors that are sensitive to near-infrared (N-IR) wavelength range or visible wavelength range radiation as alternatives or additions. These may respond to radiation emitted from a dedicated radiation source and reflected toward the display element by a hand or artificial pointing device, for example.

[0010] In the context of this application, sensing proximity is considered to mean determining whether a pointing device, in particular a user's finger, is outside or inside the proximity area of ​​a proximity sensor module. In some embodiments, the proximity sensor module may be further configured to sense whether a pointing device is in contact with it in its vicinity, and if so, the degree of pressure.

[0011] The sensitivity of the sensor can be further defined by selecting the degree of diffusion. For example, to narrow the spatial angle in which sensitivity is optimal, a material with higher diffusion can be used in the light guide.

[0012] In one embodiment, the translucent patch is provided as a region in which the second reflective layer is patterned in a mesh-like manner.

[0013] In one embodiment, the first reflective layer is positioned between the light guide and the opaque layer. A window is defined by a common opening in the first reflective layer and the opaque layer. The opening in the first reflective layer may extend beyond the boundary defined by the window, for example, to achieve reduction of localized hotspots. The opening in the opaque layer may also extend beyond the boundary defined by the window, meaning that a layer having a reflective surface becomes visible.

[0014] The opaque layer may have one or more protrusions extending toward the first principal side surface of the light guide path. This achieves selective absorption, which can be used to improve uniformity (by reducing localized hotspots).

[0015] Other layers may also be provided. These may be transparent, or they may have an opaque portion on the outside of the window. For example, one or more additional layers may be provided as a barrier to moisture and other substances and / or to protect the outer surface from scratches.

[0016] The light guide path may be formed from a transparent matrix such as polycarbonate (PC), PMMA, ABS, TPU, or PVB.

[0017] In some embodiments, the light guide can be obtained by thermoforming, as described in the unpublished European Patent Application No. 18195779.6 of the same applicant.

[0018] In one embodiment, at least one IR sensor is one of a plurality of IR sensors distributed on the second main surface and facing the first main surface through their respective translucent patches. In this embodiment, it is further possible to determine the direction of entities from which IR radiation enters the display element. Furthermore, this makes it possible to detect motion and its direction.

[0019] According to another embodiment, a proximity sensor module is provided that includes the proximity sensing indicator element described above. In the proximity sensor module, the IR sensor is one of several mutually different types of proximity sensors selected from capacitive sensors, pressure sensors, near-infrared sensors, and mid-infrared sensors, and the proximity sensor module further includes an output unit for generating a composite proximity signal based on input proximity signals emitted by the proximity sensors. The controller of the proximity sensor module performs an analysis indicating the reliability and accuracy of various sensor signals and, depending on the indicated reliability and accuracy, may provide a composite proximity signal, for example, one of the selected sensor signals, or a signal indicating a weighted sum of the distances indicated by the input sensor signals.

[0020] Embodiments of the proximity sensor module may include an optical emission sensor that receives a portion of the light emitted by at least one light-emitting element, which is reflected by a person's finger, in a direction toward the optical emission sensor through the outer surface of at least one of the aforementioned windows. The light emitted by at least one light-emitting element through the light-transmitting window passes through the window and is partially reflected by the person's finger toward the optical emission sensor. In response, the optical emission sensor generates a sensing signal representing the received light emission. The inventors have found that the sensing signal is suitable to be processed by a signal processor to derive a proximity signal indicating the degree to which a person's finger is close to the outer surface of the window, and that the proximity signal can further indicate whether the finger is in contact with the outer surface, and if so, by what pressure.

[0021] As a first approach, the signal processor bases the proximity estimate, indicated by the proximity signal, on the magnitude indicated by the sensing signal. Typically, as the user's finger approaches at least one window more closely, more light radiation is reflected, and as the pressure the user applies to the window increases, the amount of reflected radiation increases further. In fact, using a signal that shows a single component representing the intensity of radiation sensed within a single spectral range may work well when the proximity sensor module is used by a single user.

[0022] However, when the proximity sensor module is used by different users with different skin tones and / or blood circulation states, a more stable pressure / proximity indication may be obtained in embodiments of the proximity sensor module in which the light emission sensor is configured to provide a sensing signal with at least a first signal component and a second signal component indicating the respective spectral components of the received light emission. The inventors have noted, in particular, that the components of the light spectrum reflected by a person's finger are strongly dependent on the pressure applied thereby. In one embodiment, the respective spectral components of the received light emission are the red spectral component and the green spectral component. In particular, the pressure dependence of the measured contribution rates with respect to these spectral ranges differs significantly from one another, and as a result, more information is available to distinguish pressure-induced changes from other influences.

[0023] If various types of sensors are provided, the selection or weighting may be determined, for example, by the initial estimate of the distance between the object detected in relation to proximity and the surface of the display. By providing a sensitivity range for various proximity sensors, the controller can determine the reliability of the distance indications of the sensors and decide whether to select a sensor signal from any of these sensors or which weighting should be applied.

[0024] The inventors have further recognized that in known products, the visual feedback in response to user input may be invisible if the user's finger tightly covers the area where visual feedback is provided. This can be avoided by using visual feedback in a location other than the contact area, but this may confuse the user. To this end, the Disclosure provides a further embodiment in which a contact sensor is provided which emits a sensing signal indicating the extent to which a person's finger is in contact with the outer surface of at least one window. The proximity sensor module further comprises a controller coupled to the contact sensor which receives the sensing signal. The controller has at least a first operating mode which it takes when the sensing signal indicates that there is no contact with the aforementioned outer surface, and a second operating mode which it takes when the sensing signal indicates the detection of contact with the aforementioned outer surface by a person's finger. The controller is coupled to at least one light-emitting element which, in the second operating mode, emits a drive signal for controlling a controllable light source in an operating mode-dependent manner so that light emitted from the controllable light source is perceptible through a person's finger. This allows the user to observe visual feedback in the area covered by the finger. The operation of the light source may further depend on predicted or perceived environmental conditions. For example, for indoor applications, it is generally sufficient to simply use a lower intensity than for outdoor applications. Depending on the application, a predetermined setting may be used, or a light sensor may be provided to sense the brightness of the environment in which the application with a touch-sensitive graphical user interface is used. Control means may also be provided to control the setting according to the user's preference. For example, in the second operating mode, the operator may select a setting with a higher light intensity to improve visibility in situations where low light transmittance skin cannot be compensated for or where the operator's attention cannot be directly focused on the touch-sensitive graphical user interface.

[0025] In one embodiment, the spectrum of light emitted by at least one light-emitting element in the second operating mode described above is dominated by radiation having wavelengths in the range of 650–800 nm, and this range of light emission, particularly in the range of 700–780 nm, penetrates human skin relatively well. As a result, even relatively low intensity light is sufficient to provide a visual response. In one embodiment of that embodiment, in the first operating mode, the contribution of at least the red component in the light emitted by at least one light-emitting element is substantially lower than the contribution of the red component in the second operating mode. As a result, it is clearly visible to the operator whether the controller has entered the second operating mode or remains in the first operating mode. In the first operating mode, the controllable light source may be switched off by a drive signal. Alternatively, the controllable light source may be driven at a relatively low intensity other than 0, so that the controller can easily recognize the control area. Since the controllable light source is driven at a moderate intensity, it can be assumed that some light is visible through a person's finger even if the controller cannot enter the second operating mode. In the first operating mode, provided that the contribution of at least the red component in the light emitted by the controllable light source is substantially lower than that of the red component in the second operating mode, the operator can still visually distinguish between the first operating mode and the second operating mode if the first operating mode was mistakenly selected. The controller response has a small delay, e.g., 0.5 to 1.5 seconds, which allows the operator to easily compare the relatively low intensity radiation emitted through the finger immediately after contact with the control area with the relatively high intensity radiation in the second operating mode after the delay.

[0026] Alternatively or additionally, the controller may drive the light source in a modulated manner. For example, in the first operating mode, the light source may be driven continuously, and in the second operating mode, the light source may be driven in a modulated manner. In another example, in the first operating mode, the light source may be driven in a modulated manner, and in the second operating mode, the light source may be driven continuously. In both examples, the operator can clearly distinguish between the first and second operating modes. The latter example has the additional advantage of helping to focus the operator's attention on the fact that the modulated operation of the light source in the first operating mode can be input by contacting the control area. In yet another example, the light source is modulated in both the first and second operating modes, but in different ways, e.g., at different frequencies and / or different duty cycles.

[0027] In some embodiments, the contact sensor may be a pressure sensor, and the controller may be configured to emit a drive signal in a manner dependent on the pressure indicated by the aforementioned pressure sensor. This allows the operator to utilize more control options without requiring an additional area of ​​the contact-sensing graphical user interface, and provides feedback on the achieved effect through the movement of the light source visible through the person's finger.

[0028] In one embodiment of the proximity sensor module, the contribution rate of the red component is positively correlated with the amount of pressure applied to the outer surface by a human finger. The response based on the contribution rate of the red component, which is positively correlated with the amount of pressure applied to that area by a human finger, is intuitively clear to the operator. This applies, for example, to a controller's second operating mode which includes at least a first submode taken when the sensing signal indicates that the amount of pressure applied to that area by a human finger is less than a predetermined threshold, and a second submode taken when the sensing signal indicates that the amount of pressure applied to that area by a human finger is at least equal to a predetermined threshold, and the controller is configured to emit a drive signal such that the contribution rate of the red component in the second submode is higher than that in the first submode. As an example, the controller may provide a ternary response corresponding to a first operating mode (no contact detected), a first submode of the second operating mode (contact detected at a maximum moderate pressure), and a second submode of the second operating mode (contact detected at a relatively high pressure). These three operating modes can be easily distinguished from one another by the brightness of the light source visible through a person's finger (low, medium, and high, respectively). The second operating mode may include, in addition to the first and second operating submodes, one or more further submodes, each corresponding to a different range of sensing pressure. Alternatively, the controller may be configured to emit a drive signal that is a continuously increasing function of the applied pressure, such that the contribution rate of the red component in the second operating mode is indicated in the sensing signal, and the contribution rate of the red component may have a positive correlation with the amount of pressure applied by a person's finger in that region.

[0029] If the contribution rate of the red component is positively correlated with the amount of pressure applied by the human finger, the perceived response may be slightly biased in that light emitted from the light source penetrates the human finger better when higher pressure is applied. Compensation for this effect can be considered. In further embodiments, the controller is configured to emit a drive signal such that the contribution rate of the red component is modulated according to the amount of pressure applied by the human finger in that region. For example, in the case of a ternary system, contact at moderate or low pressure can be signaled using a continuously emitting light source, while contact at relatively high pressure can be signaled using an intermittently operating light source, for example, flashing every second. As a further alternative, a continuous relationship may be given between the perceived pressure and the modulation frequency.

[0030] Measures may be taken to avoid direct visibility of the relatively high intensity light necessary to penetrate human skin. This may be achieved by having the controller not enter a second operating mode until the control area is completely covered by a person's finger. Measures to delay the response to contact detection can also contribute to reducing directly visible radiation.

[0031] The amount of visible radiation may be limited by appropriately selecting the width of the illumination beam of the light source. Alternatively or additionally, the control area may be explicitly demarcated by a translucent window within an opaque zone. The illumination area defined by the translucent window and / or the beam width of the light source is relatively small, e.g., a few millimeters. 2 However, it could also be a circular or square area that can be easily and completely covered by, for example, a person's finger.

[0032] A contact-sensing graphical user interface may include multiple horizontally distributed control regions. Each control region may have a pair of contact sensors and associated controllable light sources. Control of the associated light sources may be performed according to the embodiments described above. In some embodiments, the light sources may be controlled in the same manner. This is advantageous in that the control regions provide a consistent visible response to the operator. In other situations, such as in specialized applications, it may be advantageous to give different response types to different control regions. For example, in one control region, the visible response may be an increased light intensity, and in another control region, the visual response may be a fluctuating light intensity upon contact detection. In one embodiment, a common controller may be provided to control each of the controllable light sources according to the sensing signals provided by the associated contact / pressure sensors. Alternatively, each pair of contact sensors and their associated controllable light sources may have its own dedicated controller.

[0033] According to another embodiment, a method for sensing approach to a display element is described in claim 24.

[0034] The embodiments of the method described above are A step of sensing whether a person's finger is in contact with the outer surface of at least one window (16), A step of controlling at least one light-emitting element according to an operating mode selected from a first operating mode and a second operating mode, wherein the first operating mode corresponds to a sensing signal indicating that the control area is not in contact, and the second operating mode corresponds to a sensing signal indicating that a person's finger is in contact with the control area on the contact surface, The method includes the step of controlling at least one light-emitting element so that the light emitted thereby becomes perceptible through a person's finger.

[0035] The embodiments of the method described above may be alternatively or additionally: A step of generating a sensing signal indicating light emission from at least one light-emitting element, which has passed through a light-transmitting window and been reflected by a person's finger, The process includes the step of calculating an index for the pressure applied by a human finger from a sensing signal.

[0036] The latter embodiment further includes a step of determining how the sensed signal changes with respect to time. The inventors recognize that more accurate proximity / pressure sensing can be achieved by identifying how the sensed signal changes as a function of time, rather than separating and estimating instantaneous signal values. Additionally or alternatively, an embodiment may achieve even higher accuracy in which the sensed signal includes a step of determining whether the relative change of the first component is equal to the relative change of the second component, in a method in which the sensed signal includes at least a first and second component representing the respective spectral components of the received light emission.

[0037] The above and other embodiments will be described in more detail with reference to the following drawings. [Brief explanation of the drawing]

[0038] [Figure 1] This is a schematic cross-sectional view of an embodiment of a proximity sensing display element. [Figure 2] This is a schematic cross-sectional view of another embodiment of the proximity sensing indicator element. [Figure 2A] Figure 2, part II, is a rear view of the other embodiment described above. [Figure 3] This figure shows a portion of the second reflective layer in an embodiment of a proximity sensing display element. [Figure 4] This is a schematic cross-sectional view of yet another embodiment of the proximity sensing indicator element. [Figure 5] This is a schematic diagram of an embodiment of a proximity sensor module equipped with a proximity sensing display element. [Figure 6] This figure shows in more detail the output unit that forms part of the proximity sensor module in Figure 5. [Figure 7] This is a schematic diagram illustrating the responsiveness of various sensors in the above-described embodiment of the proximity sensor module. [Figure 8A] This is a schematic front view of another embodiment of the proximity sensor module. [Figure 8B] A schematic diagram of another embodiment of the proximity sensor module, shown as a cross-sectional view in Figure 8A, VIIIB-VIIIB. [Figure 9A] This is a schematic diagram of another embodiment of the proximity sensing indicator element. [Figure 9B] This is a schematic diagram of another embodiment of the proximity sensing indicator element. [Figure 10A] This figure shows an embodiment of the method in which the above embodiment is used. [Figure 10B] This figure shows an embodiment of the method in which the above embodiment is used. [Figure 10C] This figure shows an embodiment of the method in which the above embodiment is used. [Figure 11] The above diagram shows the sensing signal as a function of the usage time. [Figure 11A] This figure shows an exemplary signal processor for processing sensing signals. [Figure 12] This is a schematic diagram showing yet another embodiment of the proximity sensing indicator element. [Figure 13] This figure shows the optical properties of human skin. [Figure 14A] This figure shows the possible operating modes according to yet another embodiment described above. [Figure 14B] This figure shows the possible operating modes according to yet another embodiment described above. [Modes for carrying out the invention]

[0039] Figure 1 schematically shows a cross-section of the proximity sensing display element 1. The proximity sensing display element 1 includes a light guide path 10, at least one light-emitting element 30, and at least one infrared sensor 40, the infrared sensor which will also be referred to as an IR sensor hereafter.

[0040] As shown in Figure 1, the light guide 10 comprises a substrate 11 having a first main surface 12 and a second main surface 14 on the opposite side. The first main surface 12 has a first reflective layer 22, and the second main surface 14 has a second reflective layer 24. The first reflective layer 22 and the second reflective layer 24 each have reflective inner surfaces 222 and 242 facing inward into the light guide. In the illustrated embodiment, the second reflective layer 24 serves as a substrate on which additional components such as an IR sensor can be supported. In other embodiments, the reflective layers may be placed on a separate substrate on the side opposite to the side having the reflective inner surface 242. At least one window 16 is defined on the first main surface 12 to allow light radiation to enter and exit the light guide. At least one light-emitting element 30, for example, an LED, is embedded in the substrate 11 on the second main surface 14 and generates light radiation within the light guide. In this example, the at least one light-emitting element 30 is one of a pair of light-emitting elements 30. Alternatively, a different number of light-emitting elements 30 may be provided. At least one IR sensor 40 is located on the second main side surface 14 of the substrate 11. At least one IR sensor faces the first main side surface 12 through a translucent patch 240 in the second reflective layer 24.

[0041] In one embodiment, the substrate 11 may be made of, for example, a thermoplastic material, such as PC, PMMA, TPU, PVB, or another thermoplastic resin.

[0042] In one embodiment, the display element 1 may have a surface area on the order of several cm × several cm, for example, 2 × 2 cm. At least one IR sensor may have lateral dimensions on the order of several mm, for example, 2 × 2 mm.

[0043] Figure 2 shows an embodiment of the proximity sensing display element 1. The proximity sensing display element 1 shown therein includes a sensor array, the sensor array comprising a plurality of IR sensors distributed on a second main surface 14 facing a first main surface 12 through each translucent patch. At least one IR sensor 40 is one of the above IR sensors. The sensor array with IR sensors may be integrated into a single configuration, for example, if the surface area is relatively small, or if the surface area is large, it may be provided as separate configurations, each comprising a single IR sensor or a subset of the array. The IR sensors may be individually addressable in order to read the values ​​sensed from each. For example, in the embodiment shown in Figure 2A, corresponding to view II in Figure 2, the designated at least one IR sensor 40 is addressed by index 3 in the row address unit 51 and by index 4 in the column address unit 52. A controller 50 is provided as an interface with an external signal processing device (not shown) and controls the row address unit 51 and the column address unit 52. This makes it possible to detect the direction in which an entity E (e.g., a user's finger) is approaching the display, facilitating more accurate identification of user input from IR radiation received from other sources. For example, knowing that entity E is a driver with a predetermined position relative to the display screen, it can be assumed that driver input is coming from a specific direction, and other detected signals are originating from other sources, such as solar radiation.

[0044] Figure 3 shows a portion of the second reflective layer 24 in an embodiment of the proximity sensing display element. This portion is shown from the reflective inner surface 242 side. The translucent patch 240 for the IR sensor 40 (outline shown by dashed line) is provided as a region in which the second reflective layer 242 is patterned in a mesh-like manner.

[0045] Figure 4 shows an embodiment of a proximity-sensing display element in which the first reflective layer 22 is positioned between the light guide path 10 and the opaque layer 26. The opaque layer 26 may have a pattern of icons to be displayed to the observer. In the embodiment shown in Figure 4, the opaque layer 26 has one or more protrusions 262 extending toward the first main surface 12 of the light guide path. This allows control of the intensity distribution visible on the first main surface 12. In the embodiment shown in Figure 4, the first reflective layer 22 may have edges 23, for example, with a width ranging from several hundred, e.g., 250 microns to several millimeters, e.g., 2 or 3 mm, and is bonded to a polymer such as polycarbonate.

[0046] Depending on the context in which the display element is used, the wavelength range of at least one IR sensor 40 may be selected. If the usage environment is relatively low temperature, at least one IR sensor may be provided as an M-IR sensor. In that case, the sensor 40 can detect infrared radiation in the wavelength range of the human body. If a heat source may be present, for example, inside a car exposed to the sun, the target object will usually emit radiation in the same range, causing a false positive. In that case, at least one IR sensor 40 may be selected not only as a near-infrared N-IR sensor, but even as a sensor for detection in the visible range. Such a sensor may be positioned so that the emitted radiation can be reflected from the object being detected towards the sensor 40 but cannot reach the sensor directly, and may be combined with a suitable radiation source (60, shown as a dashed line in the figure).

[0047] As shown in Figure 5, the proximity sensor module 2 may include a proximity sensing indicator element 1 according to one of the embodiments shown with reference to Figures 1 to 4, for example. In the embodiment of the proximity sensor module 2 shown in Figure 5, the IR sensor 40, here an M-IR sensor, is one of several proximity sensors of different types. In this illustrated embodiment, the proximity sensor module 2 further includes an N-IR sensor 41, a capacitive sensor 42, and a pressure sensor 43. The proximity sensor module 2 further includes an output unit 7 that receives input signals S emitted by the proximity sensors 40, 41, 42, and 43. 40 ,S41 ,S 42 ,S 43 Generate a proximity signal S synthesized based on this. The pressure sensor may be provided in a ring shape around the window 16. prox

[0048] FIG. 6 shows an embodiment of the output unit 7 in more detail. For each of the sensors 40, 41, 42, 43, the output unit 7 emits a standardized output signal S in response to the input signal received from the sensor. 70 ,S 71 ,S 72 ,S 73 It includes respective preprocessing units 70, 71, 72, 73 that emit this. The output signal is standardized in the sense that the same signal value of the output signal S indicates that the distance of the entity E to the surface of the display 1 is the same. The controller 75 receives the (standardized) output signals S and identifies which of these signals provides the most reliable indication of the distance, and issues a selection signal S that causes the selection element 76 to select the signal identified as the most reliable among them. The controller, for example, selects from a plurality of standardized signals S. 70 ,S 71 ,S 72 ,S 73 70 ,S<00神仙道0016>,S 72 ,S 73 el 70 ,S 71 ,S 72 ,S​​​​​However, it may be determined that the distance between the physical object and the surface of the display is within a specific range, and one of the standardized signals corresponding to the detector that typically has the best performance within that range may be selected. If the selection from the sensors is performed in a fixed order, for example, pressure sensor, capacitive sensor, N-IR sensor, M-IR sensor, then standardization for determining the selection may not be necessary. In other words, if one of these sensors is currently selected to determine the distance, and this currently selected sensor detects that the detected distance is within the lower / upper limit of the detection range assigned to it, then the sensor assigned to the detection range with the corresponding upper / lower limit is selected. Alternatively, or in addition, the selection may be made based on reliability indicators provided by the detector or its preprocessor. Furthermore, the output unit 7 may have a weighted adder that calculates a weighted sum of standardized signal values ​​instead of the selection element 76, in which case the weights assigned to these signal values ​​are positively correlated with their reliability, for example, proportional, and the sum of the weights is 1.

[0049] Figure 7 schematically shows the responsiveness of sensors 40-43 as a function of distance d. M-IR sensor 40 has a relatively wide range (d>d 01 For example, for a range from several dm to several m, the N-IR sensor 41 is in the intermediate range (d 12 <d≦d 01 For example, for distances from a few centimeters to a few dm, the capacitive sensor 42 can detect short distances on the order of a few centimeters (d 23 (=0) <d≦d 12 ) In contrast, the pressure sensor 43 is particularly suitable for the negative (compressed) range. The controller 75 outputs a standardized output signal S 70 ,S 71 ,S 72 ,S 73 Distance d from est The distance may be estimated, and subsequently, the selection element 76 may be instructed to select a standardized output signal associated with a sensor having a detection range that includes the estimated distance.

[0050] Figures 8A and 8B schematically show another embodiment of the proximity sensor module. Of these, Figure 8A shows a front view, and Figure 8B shows a cross-section shown in line VIIIB-VIIIB in Figure 8A. In this embodiment, windows 16A, 16R, and 16B are provided on the first main side surface 12 of the light guide path. Windows 16A, 16R, and 16B are formed as icons. Icon 16R represents an arrow. The proximity sensor module has a first IR sensor element 40 and a second IR sensor element 41. The controller 7 may analyze signals from them to detect the following:

[0051] A: Relatively strong steady-state input signal S 40 This is received from sensor 40. This may indicate the selection of an option corresponding to icon A.

[0052] B: Relatively strong steady-state input signal S 41 This is received from sensor 41. This may indicate the selection of an option corresponding to icon B.

[0053] C: Decreasing input signal S 40 While the input signal S is received from sensor 40, the intensity of the input signal S increases. 41 This is received from sensor 41. This may indicate the selection of an option corresponding to icon R. The response from the controller is the input signal S in the opposite sense. 40 ,S 41 While ignoring the time dependency of the function, the system may be direction-sensitive by recognizing only this time dependency as an indication that the user selected option C.

[0054] Figures 9A and 9B schematically show another embodiment of a proximity sensor module for a proximity sensing indicator element. In this embodiment, the proximity sensor module includes a light emission sensor 44. A portion of the light emission from the light-emitting element 30 that passes through the window 16 may be reflected off the outer surface 16l of the window or the surface of a person's finger F nearby and return through the window 16 in the direction of the light emission sensor 44. In response, the light emission sensor 44 sends a sensing signal I representing the received light emission. senseThe configuration is such that it generates a proximity signal I. The signal processor 7 coupled to the light emission sensor receives the sensing signal and, in response, generates a proximity signal I that indicates the degree to which a person's finger is in the vicinity of the outer surface 16l. prox The configuration is designed to generate the proximity signal I. prox It may further indicate whether it is in contact with the outer surface 16l, and if so, under what pressure.

[0055] The embodiment of the device is manufactured using a white light-emitting LED as the light-emitting element 30 and an apds-9960 sensor as the light emission sensor 44. Photographs in Figures 10A, 10B, and 10C were taken from the opposite side of the contact surface 16s under low pressure, moderate pressure, and strong pressure, respectively.

[0056] Figure 11 shows the sensing signals obtained from the light emission sensor 44 as a function of time. The sense signals R, G, and B, which represent the red, green, and blue component signals, are expressed as percentages of their nominal values.

[0057] During the time interval from t=0 to t=t1 (+ / -3s), the human finger is outside the detection range, and the signals R, G, and B are approximately 5% meaningless, likely due to internal reflections on the inner and outer surfaces of window 16.

[0058] During the time interval t1 to t2 (+ / - 4 s), the finger approaches the outer surface 16l of window 16, and as a result, all signal levels increase in conjunction. Figure 10A shows the situation at time t2.

[0059] Subsequently, during the time interval t2~t3 (8s), the pressure increases from approximately 0 to the high pressure shown in Figure 10C, via an intermediate pressure (Figure 10B), as shown in Figure 10A. Compared to the state in Figure 10A, the relative contribution of the R component is higher than that of the other components G and B, regardless of the applied pressure P.

[0060] In other words, if P > 0, then R > G > B.

[0061] However, as the pressure increases further, the ratio R / G, and to a smaller extent, B also decreases. This allows this ratio to be used as another indicator of pressure. For example, the pressure is substantially higher in the time intervals t4-t5 (12-15 seconds) and t6-t7 (22-25 seconds) than in the time intervals t5-t6 (15-22 seconds) and t7-t8 (22-37 seconds). As shown in Figure 11, the ratio R / G is approximately 1.6 while the pressure is lower, and this ratio decreases to approximately 1-3 = 1.4 while the pressure is higher.

[0062] In Figure 11, it can be further observed that all signals R, G, and B exhibit modulation corresponding to heartbeats during the time interval (t3, t4; t5, t6; t7, t8). This phenomenon may also be detected as an indication of applied pressure.

[0063] It should be noted that the proximity sensor module can also be used as a separate module in applications other than within the display element. For example, it may be used in an element that provides audible feedback indicating proximity / pressure detection, or in an element that does not provide feedback other than the effect of contact input to a controlled device. For example, the proximity sensor module may be used to control lighting equipment, where the user observes the changed lighting pattern resulting from the contact input. In one embodiment, the proximity sensor module shown in Figures 9A and 9B may be used in combination with other sensors, such as an infrared detector, in the manner described with reference to Figures 6 and 7, for example. This allows for very high accuracy in which the signal processor 7 selects the most reliable sensing signal as the output signal, or constructs the output signal from the input sensing signals by appropriately weighting the input signals according to their reliability and accuracy. Alternatively, the pressure sensor module shown in Figures 9A and 9B may be used autonomously.

[0064] Figure 11A shows the sensing signal I from the light emission sensor 44. senceAn exemplary signal processor 7 that can be used to process the light emission sensor 44 is shown. In the illustrated embodiment, the light emission sensor 44 has at least first and second signal components I that represent the respective spectral components R, G, and B of the light emission it receives. sR ,I sG ,I sB A sensing signal I sense The configuration is such that it emits a sensing signal I sense From component I sR ,I sG ,I sB To separate these components, a demultiplexing component 703 is provided. Alternatively, the light emission sensor 44 may have separate outputs for providing these components.

[0065] The signal processor 7 shown in Figure 11A provides proximity signal I, which indicates the extent to which a person's finger is near the outer surface 16l of the window 16, for example, the distance to that surface. prox It has an output for emitting a signal. The signal processor may also have a separate output for emitting a binary signal T / -T to indicate whether or not it is in contact with the outer surface 16l. Furthermore, the signal processor 7 has an output for emitting a signal I press It may have an output for emitting a signal. When in contact with the outer surface 16l, this signal indicates at what pressure it is generated. Alternatively, signal I prox However, all of this information can be provided. For example, signal I prox It may have polarity indicating whether it is in contact with the surface, and one polarity is signal I prox The magnitude of one part may indicate the distance to the surface, and the polarity of the other part is the signal I prox The size of the slash may indicate the pressure applied to the surface. In the illustrated embodiment, the signal processor 7, based on various signal characteristics, each provides an appropriate proximity indicator signal I prox1 ,I prox2 ,I prox3 ,I prox4 ,I prox5It has various proximity estimation components 710, 720, 730, 740, and 750 that generate proximity indicator signals. Each of these proximity indicator signals provides information about one or more of the distance between the finger and the surface and the pressure applied to the surface.

[0066] The first proximity estimation component 710 outputs an output signal I that shows an estimated value of proximity (or pressure) as a function of magnitude indicated by the sensing signal. prox1 It emits a signal. In this case, the magnitude of the sensing signal used for this purpose is the signal I that shows the red component R. sR It is the size of [this]. However, other signals I sB ,I sG Alternatively, one of the combinations thereof may be used for this purpose. The magnitude is known to be a substantially monotonically decreasing function with respect to distance when not in contact with the surface, and a substantially monotonically increasing function with respect to pressure when in contact with the surface.

[0067] The second and third proximity estimation components 720,730 are another component I of the sensing signal. sR Component I of the sensing signal sG ,I sB The output signal I shows proximity as a function of magnitude. prox2 ,I prox3 It emits. The second proximity estimation component 720 is signal component I sG ,I sR The output signal I is a function of the magnitude ratio shown in [the provided text]. prox2 The third proximity estimation component 730 generates the signal component I sB ,I sR The output signal I is a function of the magnitude ratio shown in [the provided text]. prox3 Generates signal I. prox2 ,I prox3 While it particularly indicates proximity in terms of contact pressure, it rarely indicates proximity in terms of distance.

[0068] The fourth proximity estimation component 740 outputs an output signal I that shows an estimate of the magnitude of proximity as a function of the change in the magnitude of the sensing signal over time. prox4emits. The magnitude of the sensed signal is the signal I calculated by the average value calculation component 707 from the signal av which is the average value shown. Or, the average value calculation component 707 uses two of the input signal components I sR ,I sG ,I sB , or the fourth proximity estimation component 740 may use one of the input signal components I sR ,I sG ,I sB as its input. The proximity estimation component 740 estimates the proximity shown by its output signal I prox4 based on the change in its input signal rather than its absolute value. In this way, the indication is independent of certain biases in the sensed signal I sense , for example, due to blood pressure or environmental temperature, for example, due to skin color.

[0069] The fifth proximity estimation component 750 emits an output signal I prox5 indicating an estimated value of proximity shown by the amplitude of the AC component in the frequency range of 50 to 220 Hz. Similar to component 740, this component 750 also uses the average value shown by the signal I av calculated by the average value calculation component 707 from those signals. Alternatively, the average value calculation component 707 uses two of the input signal components I sR ,I sG ,I sB , or the fifth proximity estimation component 750 may use one of the input signal components I sR ,I sG ,I sB as its input. The intensities R, G, B shown by the signal components I[[ID=XXX]] sR ,I sG ,I sB are modulated at a frequency corresponding to the user's heartbeat, and it has been found that when the surface is in contact with the user's finger, the amplitude is strongly correlated with the pressure applied to the surface. In particular, it has been found that the detected amplitude is a function that decreases substantially monotonically with respect to the applied pressure. When (almost) no finger is in contact with the surface, the heartbeat cannot be detected. ,I It should be noted that there seems to be an issue with the "XXX" in the translation where the tag is not fully formed in the original text. If this is an error in the original, it may need to be corrected for a more accurate translation.

[0070] As is clear from the above, various proximity indicator signals I prox1 ,I prox2 ,I prox3 ,I prox4 ,I prox5 These have different scopes of application, as summarized in the table below.

[0071] [Table 1]

[0072] The signal processor shown in Figure 11A receives the output signal I from the proximity estimation components 710, 720, 730, 740, and 750 described above. prox1 ,I prox2 ,I prox3 ,I prox4 ,I prox5 Output signal I, which shows an estimated proximity value based on this. prox The system further includes a combination component 705 that calculates the signal I. prox The output signal I prox1 ,I prox2 ,I prox3 ,I prox4 ,I prox5 The weighted average of the proximity (distance / pressure) shown for each of these can be shown according to the estimated accuracy of each. In one embodiment, the weighting may be binary, and signal I prox1 ,I prox2 ,I prox3 ,I prox4 ,I prox5 One of them is output signal I prox The coupling component is selected as one or more (standardized) output signals S from one or more other sensors 40, 41, 42, 43, as shown in Figure 6, for example. 70 ,S 71 ,S 72 ,S 73The following may also be used. For example, provided that a light-transmitting material (e.g., a transparent conductive oxide, e.g., ITO) is used for the capacitive sensor 42, the capacitive sensor 42 may be provided near the window 16, or possibly inside the region defined by the window, for this purpose.

[0073] Figure 12 schematically shows yet another embodiment of the proximity sensing indicator element. In this embodiment, a sensing signal I indicates the degree to which a person's finger is in contact with the outer surface 16l of the window 16. sense To emit the signal, a contact sensor 45 is provided, for example, one of the sensors 40, 41, 42, 43 shown in Figure 6, or the sensors shown in Figures 9A and 9B, or a combination thereof. Furthermore, the controller 8 is coupled to the contact sensor 45 and receives the sensing signal I sense The controller receives a signal. As shown in Figures 14A and 14B, the controller has at least two potential operating modes: a first operating mode M1 and a second operating mode M2. The controller 8 is configured to take the first operating mode M1 when the sensing signal indicates that it is not in contact with the outer surface, and to take the second operating mode M2 ​​when the sensing signal indicates that a person's finger has come into contact with the outer surface 16l. In the second operating mode, the controller 8 controls a controllable light source according to the operating mode, so that the light emitted from the controllable light source, which is coupled to the light-emitting element 30, becomes perceptible through a person's finger. driveThis emits light. This allows for visual feedback at the position where the user's finger covers the window. In this embodiment, the spectrum of light emitted from the light-emitting element 30 in the second operating mode is dominated by radiation having wavelengths in the range of 650 to 800 nm. As schematically shown in Figure 13, human skin has relatively high light transmittance in this spectral range, particularly in the range of 700 to 780 nm, and this radiation is sufficiently perceptible to the user. Therefore, a relatively low intensity is considered sufficient. In the first operating mode M1, it is not necessary for the light emission to be visible. Therefore, in the first operating mode M1, the contribution rate of at least the red component of the light irradiated by the light-emitting element 30 may be substantially lower than the contribution rate of the red component in the second operating mode M2. Thus, since the light irradiated from a controllable light source is perceptible through a person's finger only in the second operating mode, the detection of contact can be visualized. Alternatively, the controller 8 modulates the contribution rate of at least the red component in the emitted light according to the operating mode of the controller using a drive signal I drive It may also be configured to emit a signal.

[0074] The contact sensor 45 may be provided as a pressure sensor, for example, as described with reference to Figures 9A and 9B, and the controller 8 drives the drive signal I in a pressure-dependent manner as shown by the pressure sensor. drive The controller may be configured to emit a drive signal. In the embodiment shown in Figure 14B, this applies in that the second operating mode M2 ​​of the controller 8 includes at least a first submode M21 taken when the sensing signal indicates that the amount of pressure applied by a person's finger over that area is less than a predetermined threshold, and a second submode M22 taken when the sensing signal indicates that the amount of pressure applied by a person's finger over that area is at least equal to a predetermined threshold, and the controller is configured to emit a drive signal such that the contribution rate of the red component in the second submode is higher than in the first submode.

[0075] Alternatively, the contribution rate of the red component in the second operating mode M2 ​​is the same as that of the sensing signal I senseThe drive signal I is such that it becomes a function that increases continuously with respect to the applied pressure, as shown in [the diagram]. drive In that the controller is configured to emit a certain light, the contribution rate of the red component may be positively correlated with the amount of pressure applied by a person's finger.

[0076] The drive signal I modulates the contribution rate of the red component according to the amount of pressure applied by a human finger on region 16l. drive It may also be configured with a controller 8 that emits a signal.

[0077] In some embodiments, the controller does not enter the second operating mode until the control area 16l is completely covered by a person's finger. This prevents the user's eyes from being partially desensitized due to light emission before the area is covered. This makes it easier to perceive the light emission that has passed through the person's finger. As an additional measure, a delay of, for example, 0.2 to 0.7 seconds may be given to the state transition to the second operating mode.

[0078] In one embodiment, the control region 16s is one of a plurality of control regions distributed laterally on the contact surface, and each of the plurality of control regions distributed laterally may have a pair of contact sensors and associated controllable light sources.

[0079] In the claims, the word “comprising” does not exclude other elements or steps, and the indefinite article “a” or “an” does not exclude plurals. A single component or other unit may perform the functions of several items described in the claims. The mere fact that certain countermeasures are described in different claims does not imply that combinations of these countermeasures cannot be used advantageously. Reference numerals in the claims should not be construed as limiting their scope.

Claims

1. A portion of the light radiation emitted by at least one light-emitting element (30), which is reflected by a person's finger in the direction toward the light emission sensor (44) after passing through the outer surface of at least one window (16) and through the light-transmitting window, is received and a sensing signal (I) representing the received light radiation is generated. ｓｅｎｓｅ A light emission sensor (44) for generating ) and The system detects contact by the finger, is coupled to the optical emission sensor, receives the sensing signal, and in response, if contact is detected, generates a proximity signal (I) indicating the pressure applied by the human finger as a function of the magnitude indicated by the sensing signal. ｐｒｏｘ A signal processor (7) that generates ) Equipped with, The aforementioned light emission sensor (44) At least first and second signal components (I) that show the red spectral component (R) and the green spectral component (G) in the light emission. ｓＲ , I ｓＧ The sensing signal (I ｓｅｎｓｅ ) emits, The signal processor (7) is The first component of the sensing signal (I ｓＲ The second component of the sensing signal (I ｓＧ The proximity estimation component (720) has an output signal (Iprox2) that shows an estimated proximity value as a function of the magnitude of ). Proximity sensor module.

2. The signal processor (7) outputs an output signal (I) that shows an estimated value of proximity as a function of the change in the magnitude of the sensing (component) with respect to time. ｐｒｏｘ４ The proximity estimation component (740) that emits ) The proximity sensor module according to claim 1.

3. The signal processor (7) further has a proximity estimation component (750) that emits an output signal (I ｐｒｏｘ５ ) indicating an estimated value of proximity, which is indicated by the amplitude of the AC component in the frequency range of 50 to 220 Hz. The proximity sensor module according to claim 1 or 2.

4. The signal processor (7) outputs an output signal (I) indicating an estimated value of proximity based on the output signal from the proximity estimation component. ｐｒｏｘ A proximity sensor module according to any one of claims 1 to 3, comprising a coupling component that generates ).

5. A proximity sensing display element comprising a proximity sensor module according to any one of claims 1 to 3, A light guide path (10) comprising a substrate (11) having first and second main sides (12, 14) facing opposite directions and each having first and second reflective layers (22, 24), wherein the first and second reflective layers (22, 24) have reflective inner surfaces (222, 242) facing the inside of the light guide path, and at least one window (16) is provided on the first main side so that light radiation can enter and exit the light guide path, For generating light emission within the light guide path, comprising at least one light-emitting element (30) located on the second main side surface of the substrate, The second reflective layer (24) has a translucent patch (240) that faces the first main surface and is positioned on the second main surface of the substrate, and the second reflective layer (24) has a translucent patch (240) that faces the first main surface, The IR sensor is one of several mutually different types of proximity sensors selected from capacitive sensors, pressure sensors, near-infrared sensors, and mid-infrared sensors. The proximity sensor module further comprises an output unit that generates a composite proximity signal based on the input proximity signal emitted by the proximity sensor. The output unit includes a selection unit and a controller that causes the selection unit to select an input proximity signal from a specific one of the proximity sensors when the estimated value of the sensor is within the sensitivity range of the proximity sensor. Proximity sensing indicator element.

6. The sensor array comprises a plurality of IR sensors distributed on the second main surface facing the first main surface through each translucent patch, The at least one IR sensor (40) is one of the IR sensors, The proximity sensing display element (1) according to claim 5.

7. The translucent patch (240) is provided as a region in which the second reflective layer is patterned in a mesh-like manner. The proximity sensing display element according to claim 5.

8. The first reflective layer (22) is positioned between the light guide path (10) and the opaque layer (26). The proximity sensing indicator element according to any one of claims 5 to 7.

9. The opaque layer (26) has one or more protrusions (262) extending toward the first main side surface (12) of the light guide path. The proximity sensing indicator element according to claim 8.

10. A proximity sensing display panel comprising a proximity sensing display element according to any one of claims 5 to 9.

11. A proximity sensor module comprising a light emission sensor (44) and a signal processor (7) A method for detecting the proximity of a human finger (F) to the outer surface (16l) of a translucent window (16), and, if contact is made by the finger, detecting the pressure applied by the finger, Light emitted from at least one light-emitting element (30) is transmitted through the translucent window. The light emission sensor (44) generates a sensing signal indicating the emission of light emitted by the at least one light-emitting element (30) and reflected by a human finger (F) through the translucent window. The sensing signal (I ｓｅｎｓｅ )teeth, The first and second signal components (I) show the red spectral component (R) and the green spectral component (G) in the light emission. ｓＲ , I ｓＧ ) has at least, The signal processor (7) processes the first component (I) of the sensing signal. ｓＲ The second component of the sensing signal (I ｓＧ As a function of the magnitude of the sensing signal, the pressure applied by the human finger (I ｐｒｅｓｓ A method for calculating ).

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