Hearing device system and methods for operating hearing device system

Abstract

The invention relates to a hearing device system and a method for operating a hearing device system. The hearing device system has a photoplethysmographic pulse wave sensor (12) and an earplug (24) which can be worn in the ear canal in a normal wearing state, the earplug covering the photoplethysmographic pulse wave sensor (12) at least partially in the normal wearing state. Furthermore, the hearing device system has a controller (6) which is configured to derive, from light detected by means of the photoplethysmographic pulse wave sensor (12), a contrast variable (TI) of the earplug (24) which characterizes the transmission (T) of the earplug (24) for a wavelength range of the photoplethysmographic pulse wave sensor (12), to compare the contrast variable (TI) with a first limit value (G1) specified in advance and to output a warning message when the contrast variable (TI) exceeds the limit value (G1).

Description

Technical Field

[0001] This invention relates to a hearing aid system. Furthermore, this invention relates to a method for operating such a hearing aid system. Background Technology

[0002] Hearing devices are typically used to output acoustic signals to the ears of the wearer. This output is made via an output transducer, usually acoustically via a speaker (also called a "hearing tube" or "receiver") through airborne sound. Such hearing devices are often referred to as so-called hearing aids (or simply hearing aids). For this purpose, hearing devices typically include an acoustic input transducer (particularly a microphone) and a signal processor configured to process the input signal (also called a microphone signal) generated by the input transducer based on ambient sound using at least one signal processing algorithm, typically stored in a user-specific manner, so as to at least partially compensate for the hearing impairment of the wearer. Particularly in the case of hearing aids, in addition to a speaker, the output transducer may alternatively be a so-called bone conduction hearing tube or cochlear implant, configured to mechanically or electrically couple acoustic signals into the wearer's ear. The term "hearing device" also includes, in particular, devices such as so-called tinnitus maskers, headphones, and earphones.

[0003] Similar to the growing popularity of wearable devices, particularly those that use sensors to detect bodily functions such as pulse and movement (e.g., fitness trackers, smartwatches), this functionality is also being adopted in the field of hearing devices. For example, it's used to detect body temperature and pulse. This additional use of hearing devices is particularly relevant in the case of hearing aids, which are typically worn close to the body and often for relatively long periods or even continuously. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to improve the detection of bodily functions with the aid of hearing devices.

[0005] According to the present invention, the above-mentioned technical problems are solved by a hearing device having the features of the present invention. Furthermore, according to the present invention, the above-mentioned technical problems are solved by a method having the features of the present invention. In the following description, advantageous embodiments and extensions of the invention, which are themselves inventive, are illustrated.

[0006] The hearing device system according to the invention includes a photoplethysmography (PPG) sensor, which can be worn in the ear canal of a person using the hearing device system in a normal wearing state. Furthermore, the hearing device system includes an earplug that, in a normal wearing state, at least partially covers the PPG sensor towards the ear canal. Specifically, the earplug is used to at least indirectly hold the PPG sensor in a normal wearing position within the ear canal. Additionally, the hearing device system includes a controller configured to derive a contrast parameter characterizing the transmission of the earplug, based on light detected (and preferably emitted) by the PPG sensor, for a wavelength range used by the PPG sensor. Furthermore, the controller is configured to compare the contrast parameter with a pre-given first boundary value and output a warning message when the contrast parameter exceeds the boundary value.

[0007] According to the method of the invention, in order to operate the hearing device described above (that is, the hearing device having a photoplethysmography sensor and an earplug, the photoplethysmography sensor being wearable in the ear canal in a normal wearing state, and the earplug covering the photoplethysmography sensor at least partially towards the ear canal in a normal wearing state), a contrast parameter for transmission to the earplug is derived based on the light detected by means of the photoplethysmography sensor, for the wavelength range of the photoplethysmography sensor, the contrast parameter is compared with a pre-given first boundary value, and a warning message is output when the contrast parameter exceeds the boundary value.

[0008] In other words, the hearing device system, specifically its controller, is configured to, in particular, automatically execute the method according to the invention. Conversely, the method correspondingly includes all the measures performed by the controller as described herein and below. Therefore, the hearing device system and the method share, in a corresponding manner, the features (particularly methodological) described herein and below, and the advantages thereby derived.

[0009] Characterization here and below means that the contrast parameter contains quantitative information about the magnitude of transmission, thus allowing transmission to be discerned at least indirectly from the contrast parameter. Therefore, the contrast parameter, for example, gives the transmission itself (particularly the transmission along the entire propagation path of light in a photoplethysmography sensor), or alternatively, absorption complementary to the transmission. The contrast parameter can also be a parameter directly or indirectly proportional to the transmission to be shown. Furthermore, the contrast parameter may also have a nonlinear relationship with the transmission to be shown, such as a logarithmic, exponential, or polynomial (i.e., quadratic, cubic, etc.) relationship.

[0010] The term "exceeding a boundary value" (here, exceeding the first boundary value) should preferably always be understood, both here and below, in the sense that the sign of the difference between the contrast parameter (or its change over time) and the boundary value changes is independent of direction. That is, according to the definition of the contrast parameter ("true" transmission or absorption), exceeding the corresponding boundary value can be positive (in the sense of truly exceeding, where the contrast parameter is greater than the boundary value) or negative (in the sense of being less than, where the contrast parameter is less than the boundary value). Therefore, in particular, a warning message is output when the contrast parameter reflects absorption and is greater than the first boundary value. Conversely, it is preferable to output a warning message when the contrast parameter reflects transmission and is less than the first boundary value.

[0011] Because the measurement principle of a photoplethysmography (PPG) sensor is based on illuminating body tissue with light from one or more pre-defined wavelength ranges (e.g., different bands of the near-infrared and / or visible wavelength ranges) and detecting the reflected or transmitted radiation to determine tissue characteristics, particularly current blood flow, the transmission of light from the earpiece significantly affects the assessment and determination of tissue characteristics. Therefore, it is preferable to select (pre-defined) the first boundary value described above such that sufficient light is still received for the assessment and determination of tissue characteristics. In other words, the first boundary value preferably defines a boundary beyond which reliable assessment and determination of tissue characteristics can no longer be achieved. Thus, by determining a contrast parameter and comparing it to the first boundary value, it is advantageous to inform users of hearing aid systems about the limitations of the PPG sensor's functionality.

[0012] In a preferred embodiment, the controller is configured to compare a comparison parameter with a second boundary value in addition to a first boundary value, and to infer a first type, particularly a first color type, of the earplug based on the position of the comparison parameter relative to the second boundary value. This is particularly suitable in that, for hearing devices, earplugs with different color designs (i.e., different color types) may often be used. However, not all color designs (even if the earplug is translucent) are suitable for reliable (providing sufficiently accurate results) use with photoplethysmography (PPG) sensors because at least a significant portion of the light is absorbed.

[0013] In a suitable extension of the embodiment described above, the controller is configured to compare the comparison parameter with a third boundary value. In this case, the first boundary value lies between the second and third boundary values. Here, the controller is specifically configured to infer a second type, particularly a second color type, of the earpiece based on the position of the comparison parameter relative to the third boundary value. That is, in particular, the controller is configured to distinguish between color types with sufficiently high transmittance and color types with excessively low transmittance. This is particularly advantageous in that, for hearing devices, different earpieces with different color designs (i.e., different color types) may often be used, such as light-colored, dark-colored, transparent, opaque, etc. Preferably, the controller is configured to output a recommendation for a suitable type when it detects an earpiece type, particularly a color type, that is unsuitable for use with a photoplethysmography (PPG) sensor.

[0014] For example, the second boundary value (for the second boundary value, and therefore the comparison parameter also reflects the transmission itself) is above the first boundary value (i.e., the value representing the transmission itself is larger than the value set by the first boundary value). In this case, the third boundary value is particularly below the first boundary value, thus representing a significantly low transmission.

[0015] Optionally, multiple second and / or third boundary values ​​are also pre-defined, which, for example, can distinguish multiple color designs or multiple earbuds from different manufacturers.

[0016] In a suitable implementation, the controller is configured to use a comparison parameter exceeding a first boundary value as an indication that the earplugs are contaminated, and to output a warning message requesting that the earplugs be cleaned or replaced.

[0017] In identifying contamination in an advantageous combination with the previously described comparison to a second boundary value or also a third boundary value, the controller is suitably configured to deduce contamination when it exceeds only the first boundary value but not the second or third boundary value. Advantageously, when the color type of the earpiece unsuitable for use with the photoplethysmography (PPG) sensor has low transmittance (in other words, high absorption), contamination can be detected when the distance from the first boundary value, from which the use of the PPG sensor is significantly affected, to the reduced transmittance value typically due to contamination, is smaller compared to the second or third boundary value associated with the unsuitable color type. Therefore, in this case, not only the unsuitable color type but also the contamination results in the output of a warning message, preferably a correspondingly associated different warning message.

[0018] In a preferred embodiment, the hearing device system includes a hearing device (particularly a hearing aid device) to which a photoplethysmography (PPG) sensor is coupled. Specifically, the PPG sensor is part of the hearing device. In this case, the controller is suitably configured to determine a contrast parameter after earplug replacement and / or after activation of the hearing device, and preferably also to compare it with a boundary value or a corresponding boundary value. Optionally, the controller is configured to repeatedly determine the contrast parameter during continuous operation of the hearing device, and particularly also to compare it with a boundary value or a corresponding boundary value.

[0019] In a suitable implementation, a first boundary value, and if necessary, a second and / or a third boundary value, is selected such that the influence of body tissue on the light emitted by the photoplethysmography (PPG) sensor is taken into account. In other words, the corresponding boundary values ​​are selected such that a contrast parameter is determined after irradiation of the body tissue. It is well known that body tissue (besides the earplugs) causes the emitted light to "attenuate." Therefore, the preferred first boundary value indicates how much light must be detected for the correct, and particularly reliable, use of the PPG sensor after irradiation of the user's body. Correspondingly, the second or third boundary value (if present) indicates how much light must be detected after irradiation of the body in order to assign the appropriate color type to the earplugs.

[0020] Preferably, the first (and especially the second and third) boundary values ​​reflect the ratio of the amount of light received (intensity) to the amount of light emitted. In particular, the first boundary value is at least 65% in the wavelength range around 860 (+ / - 20) nanometers.

[0021] In another suitable embodiment, the hearing device includes a body that can be worn behind the ear, the body including a signal processor and at least one microphone coupled thereto. Furthermore, in this case, the hearing device includes a speaker that can be worn in the ear canal and coupled to the signal processor via signal transmission technology. In particular, the hearing device is an behind-the-ear hearing aid device (also known as "BTE," short for "behind the ear") with an external speaker (especially also referred to as "RIC" or "RIC-BTE"). In this embodiment, the speaker preferably carries a photoplethysmography (PPG) sensor, which is particularly integrated into the speaker.

[0022] Especially in the case of the aforementioned “RIC” hearing aid devices, (particularly those suitable or configured for use with photoplethysmography sensors) the earplug is preferably formed as a flexible cover for the speaker and is made of a transparent, particularly colorless, material. For example, the earplug (also referred to as an “ear dome” in this case) is made of silicone. Conversely, earplugs unsuitable for use with photoplethysmography sensors are made of, for example, (particularly dark) colored materials, particularly silicone.

[0023] Alternatively, the controller of the hearing device system described above is constructed as a non-programmable electronic circuit. Alternatively, the controller is formed as a microcontroller, wherein the functions for performing the methods described above according to the invention are implemented in the form of software modules.

[0024] In one alternative implementation, the controller is integrated into the signal processor of the hearing device. In an alternative, optional, and additional implementation (e.g., to selectively accommodate power-saving modes for the hearing device), the controller is configured to be implemented externally to the hearing device, such as as an app (i.e., the aforementioned software module) on a smartphone. Therefore, particularly when an app is installed, the smartphone is part of the hearing device system at least while the app is in use. In this case, it is preferable to wirelessly transmit the data (especially the sensor signal) from the photoplethysmography sensor to the smartphone via the hearing device's communication interface. Attached Figure Description

[0025] The embodiments of the present invention will now be described in detail with reference to the accompanying drawings. Wherein:

[0026] Figure 1 A schematic diagram illustrates a hearing device system with an external speaker and a photoplethysmography (PPG) sensor.

[0027] Figure 2 A schematic partial cross-sectional view shows a speaker and a photoplethysmography (PPG) sensor in their normal wearing position within a user's ear canal, and

[0028] Figure 3 , 4 The comparative parameters determined by the transmission of the earplug using a photoplethysmography (PPG) sensor under normal wearing conditions are illustrated in the diagrams.

[0029] Corresponding parts and parameters are always given the same reference numerals in all the figures. Detailed Implementation

[0030] exist Figure 1The image shows a hearing aid device, specifically a hearing aid device (also abbreviated as a hearing aid, referred to herein as "BTE 1") that can be worn behind a user's ear. BTE 1 includes a housing 2, within which the electronic components of BTE 1 are arranged. These electronic components include, for example, two microphones 4, a signal processor 6, and a battery module 8. During normal operation of BTE 1, the microphones 4 receive ambient sound and convert it into an electrical input signal (also referred to as "microphone signal MS"). The signal processor 6 (also referred to as "controller") processes the electrical input signal (specifically, filtering, frequency-dependent amplification, and / or attenuation, etc.). The processed input signal is then output as an output signal AS to a speaker 10, which is located outside the housing 2 and can typically be worn in the ear canal 9. The speaker 10 converts the output signal AS into a sound signal and transmits it to the user's ear.

[0031] In addition, BTE 1 has a photoplethysmography (PPG) sensor, referred to simply as "PPG sensor 12". In the current embodiment, PPG sensor 12 is integrated into speaker 10, specifically inserted into its housing 14 (see [link]). Figure 2 The PPG sensor 12 is used, for example, to determine the pulse of a user with BTE 1, and optionally also to determine oxygen saturation. For this purpose, the PPG sensor 12 includes a light source, in this case an LED unit 16, which is configured to output light in multiple frequency bands, but typically outputs light in at least the near-infrared range. Furthermore, the PPG sensor 12 includes a light sensor 18 for detecting the incident light. During normal operation, the light sensor 18 detects the light beam output by the LED unit 16 and reflected by body tissue, such as the vessel wall 20 of the user's blood vessel 22. The user's pulse can then be determined, for example, based on the intensity changes detected therein.

[0032] Furthermore, to hold the speaker 10 within the ear canal 9, the BTE 1 is equipped with an earplug, specifically formed by a mushroom-shaped flexible cap referred to as a "cover 24" (or "sleeve"). As in Figure 1 and 2 As can be seen, the cover 24 at least partially covers the PPG sensor 12. That is, due to the inherent absorption of the material of the cover 24 (i.e., less than 100% transmission), light is attenuated, especially along its path between the LED unit 16 and the photosensor 18. Depending on the color design of the cover 24, this attenuation is more or less pronounced. For BTE 1, different colors of the cover 24 can typically be used, mostly colorless and dark-colored variations.

[0033] BTE 1, together with the currently used Mask 24, forms a "hearing device system".

[0034] However, for routine use, specifically for reliable results from the PPG sensor 12, a pre-defined intensity value received by the light sensor 18 is required. Therefore, the signal processor 6 is configured to determine a contrast parameter characterizing the transmission of the cover 24 based on the detected light (optionally for each emitted wavelength band or, exemplary, only for one wavelength band). Here, this contrast parameter (here referred to as the "actual transmission value TI") is determined as the ratio between the intensity of the detected light and the intensity emitted by the LED unit 16. It is well known that this actual transmission value TI includes not only attenuation through the cover 24 but also attenuation through the user's body tissues. Figure 3 A graph depicting transmission T relative to wavelength λ is shown. Here, the variation of the actual transmission value TI across the detected wavelength range is illustrated by way of example.

[0035] Subsequently, signal processor 6 compares the actual transmission value TI with a pre-defined first boundary value G1 (see...). Figure 3 A comparison is made. The first boundary value G1 is selected such that below this first boundary value G1, reliable function of the PPG sensor 12 is not guaranteed, i.e., excessive attenuation (absorption) through the cover 24 and body tissues. For example, in... Figure 3 As shown, if the actual transmission value TI is above the first boundary value G1, then the signal processor 6 continues normal operation. If the actual transmission value TI is below the boundary value G1, then the signal processor 6 outputs a warning message.

[0036] To further clarify the warning message, in another embodiment (see...) Figure 4 In the signal processor 6, the second boundary value G2 and the third boundary value G3 are stored. Here, the second boundary value G2 is above the first boundary value G1, and the third boundary value G3 is below the first boundary value G1.

[0037] Therefore, the signal processor 6 can also distinguish between different types of covers 24, specifically different colors of covers 24, specifically light-colored or colorless covers and dark-colored covers 24. If the actual transmission value TI is lower than the first boundary value G1 and the third boundary value G3, then the signal processor 6 infers that a cover 24 with a dark distortion scheme has been installed. The signal processor 6 outputs an indication that a cover 24 with a colorless distortion scheme has been installed using a warning message.

[0038] If the actual transmission value TI exceeds the second boundary value G2, then the signal processor 6 infers that the cover 24 with the colorless deformation scheme is installed.

[0039] In another embodiment, if the actual transmission value TI is lower than the first boundary value G1 but not lower than the third boundary value G3, the signal processor 6 infers that the cover 24 is contaminated, for example, due to earwax buildup on the cover 24. In this case, the signal processor 6 outputs a warning message recommending cleaning or replacing the cover 24.

[0040] In an embodiment not shown in detail, the aforementioned hearing device system also includes a smartphone on which a software application configured and set to evaluate data from the PPG sensor 12 is implemented. In this embodiment, the application is also configured to perform the “monitoring” of the transmission of the cover 24 previously performed by the signal processor 6. That is, in this case, the smartphone, specifically its microprocessor, in conjunction with the application, forms a controller that determines the actual transmission value TI and compares it with a first boundary value G1, and if necessary, with a second boundary value G2 and a third boundary value G3, and outputs a warning message if necessary. In this case, the BTE 1 has a wireless interface by means of which the data from the PPG sensor 12 is transmitted to the smartphone.

[0041] The subject matter of this invention is not limited to the embodiments described above. Rather, those skilled in the art can deduce other embodiments of the invention based on the foregoing description. In particular, the various features and design variations of the invention described with reference to different embodiments can also be combined with each other in other ways.

[0042] List of reference numerals

[0043] 1 BTE

[0044] 2. Shell

[0045] 4 microphones

[0046] 6. Signal Processor

[0047] 8 Battery Modules

[0048] 9 Ear canal

[0049] 10 speakers

[0050] 12 PPG sensors

[0051] 14. Shell

[0052] 16 LED units

[0053] 18. Light Sensor

[0054] 20. Blood vessel wall

[0055] 22 blood vessels

[0056] 24 masks

[0057] MS microphone signal

[0058] AS output signal

[0059] T transmission

[0060] TI Actual Transmittance Value

[0061] G1 First boundary value

[0062] G2 Second Boundary Value

[0063] G3 Third Boundary Value

[0064] λ wavelength

Claims

1. A hearing device system having: - an opto-plethysmographic pulse wave sensor (12) which can be worn in an ear canal in a regular wearing state, - an ear plug (24) which covers the opto-plethysmographic pulse wave sensor (12) at least partially towards the ear canal (9) in a regular wearing state, and - a controller (6), the controller being configured to derive, from light detected by means of the opto-plethysmographic pulse wave sensor (12), a contrast parameter (TI) of the ear plug (24) characterizing a transmission (T) of the ear plug (24) for a wavelength range of the opto-plethysmographic pulse wave sensor (12), to compare the contrast parameter (TI) with a predefined first boundary value (Gl) and to output a warning message when the contrast parameter (TI) exceeds the first boundary value (Gl), wherein the controller (6) is configured to compare the contrast parameter (TI) with a second boundary value (G2) and to derive a first type of the ear plug (24) depending on a position of the contrast parameter (TI) relative to the second boundary value (G2), and wherein the controller (6) is configured to compare the contrast parameter (TI) with a third boundary value (G3), wherein the first boundary value (Gl) is between the second boundary value (G2) and the third boundary value (G3), and to derive a second type of the ear plug (24) depending on a position of the contrast parameter (TI) relative to the third boundary value (G3).

2. The hearing device system according to claim 1, the controller (6) being configured to compare the contrast parameter (TI) with the second boundary value (G2) and to derive a first color type of the ear plug (24) depending on a position of the contrast parameter (TI) relative to the second boundary value (G2).

3. The hearing device system according to claim 2, the controller (6) being configured to compare the contrast parameter (TI) with the third boundary value (G3) and to derive a second color type of the ear plug (24) depending on a position of the contrast parameter (TI) relative to the third boundary value (G3).

4. The hearing device system according to any one of claims 1 to 3, the controller (6) being configured to use the contrast parameter (TI) exceeding the first boundary value (Gl) as an indication that the ear plug (24) is contaminated and to output a request to clean or replace the ear plug (24) with the warning message. wherein 5. The hearing device system according to claim 2 or 3, the controller (6) being configured to use the contrast parameter (TI) exceeding the first boundary value (Gl) as an indication that the ear plug (24) is contaminated and to output a request to clean or replace the ear plug (24) with the warning message. ​ ​ ​ wherein ​ ​ wherein, ​ ​ wherein ​ ​ wherein ​ wherein the controller (6) is configured to infer contamination when only the first limit value (Gl) is exceeded, but not the second limit value (G2) or the third limit value (G3).

6. The hearing device system according to any one of claims 1 to 3, The hearing device system has a hearing device (1), the photoplethysmographic pulse wave sensor (12) is coupled with the hearing device (1), wherein, the controller (6) is configured to determine the contrast variable (TI) after replacement of the earplug (24) and / or after activation of the hearing device (1).

7. The hearing device system according to any one of claims 1 to 3, wherein the first limit value (Gl), the second limit value (G2) and / or the third limit value (G3) are chosen with consideration of the influence of body tissue on the light emitted by the photoplethysmographic sensor (12).

8. The hearing device system according to any one of claims 1 to 3, wherein, the hearing device (1) has a main body which can be worn behind the ear, the main body comprising a signal processor (6) and at least one microphone (4) coupled to the signal processor, and an earpiece which can be worn in the ear canal and is coupled to the signal processor (6) by signal transmission technology, wherein the earpiece (10) carries the photoplethysmographic sensor (12).

9. The hearing device system according to claim 8, wherein the earplug (24) is configured as a flexible cover for the earpiece (10) and is formed from a transparent material.

10. The hearing device system according to claim 8, wherein, the earplug (24) is configured as a flexible cover for the earpiece (10) and is formed from a transparent and colorless material.

11. A method for operating a hearing device system having a photoplethysmographic sensor (12) which can be worn in an ear canal (9) in a normal wearing state and an earplug (24) which covers the photoplethysmographic sensor (12) towards the ear canal (9) in a normal wearing state, wherein the method comprises: - deriving a contrast variable (TI) characterizing the transmission (T) of the earplug (24) for a wavelength range of the photoplethysmographic sensor (12) from light detected by means of the photoplethysmographic sensor (12), - comparing the contrast variable (TI) to a predefined first limit value (Gl), - outputting a warning message when the contrast variable (TI) exceeds the limit value (Gl), - comparing the contrast variable (TI) to a second limit value (G2) and deriving a first type of the earplug (24) depending on the position of the contrast variable (TI) relative to the second limit value (G2), and - outputting a warning message when the contrast variable (TI) exceeds the second limit value (G2). - comparing said comparison parameter (TI) with a third boundary value (G3), wherein said first boundary value (G1) is between said second boundary value (G2) and said third boundary value (G3), and deriving a second type of said earplug (24) as a function of the position of said comparison parameter (TI) with respect to said third boundary value (G3).

12. The method according to claim 11, wherein - comparing said comparison parameter (TI) with said second boundary value (G2), and deriving a first color type of said earplug (24) as a function of the position of said comparison parameter (TI) with respect to said second boundary value (G2).

13. The method according to claim 12, - comparing said comparison parameter (TI) with said third boundary value (G3), and deriving a second color type of said earplug (24) as a function of the position of said comparison parameter (TI) with respect to said third boundary value (G3).

Images