TECHNICAL FIELD

The present disclosure relates generally to an earphone device, and to a method for an earphone device. In particular, the earphone device may comprise an ear adjustment unit and a processor. The ear adjustment unit comprises an eartip and a sensor. The ear adjustment unit may be adapted to be adjusted to a user’s ear. The sensor may detect a sound signal in the ear canal, and the processor may estimate an eartip fit quality based on the detected sound signal.

BACKGROUND

Generally, some conventional earphones devices are based on insert-type earphones. Such insert-type earphones may have the ability to passively attenuate outside noises, and thus may offer an improved listening experience. Moreover, conventional insert-type earphones typically comprise a body part and an eartip part. The eartip part is often designed to be pushed inside a user’s ear canal, for example, in order to block it from outside sounds, and to further allow the sounds generated by the earphones entering the user’s ear canal.

A conventional earphone device exist that measures whether the eartip is correctly positioned in the ear canal or if there is a leak. For example, a conventional earphone device uses excitation sounds which it plays into the ear canal, in order to measure the eartip fit quality. For example, the eartip quality can be estimated from the sonic response using an insert microphone facing the ear canal. However, an issue of such conventional device is that, the user of the earphone device needs to first listen to an excitation or a measurement sound, before knowing a result of the eartip fit quality.

However, an issue of such conventional earphone device is that the excitation sound makes it difficult for the eartip fit test to operate non-invasively in the background, and only notify the user to correct the eartip if the fit is bad, which could be seen as an optimal operation. Moreover, when non-audible excitation signals is used in the eartip fit measurement, the result might not be optimal as many earphone devices are not designed to reproduce well sounds outside the human hearing range, and could thus require costly redesign or at least increased power consumption when reproducing non-audible sounds.

SUMMARY

In view of the above-mentioned problems and disadvantages, embodiments of the present disclosure aim to improve a conventional earphone device and a method for an earphone device.

An objective is to provide an earphone device that estimates the eartip fit quality of insert headsets. For instance, the earphone device and/or the method for the earphone device may perform an acoustic eartip fit quality test without playing an excitation sound. For example, the earphone device of the present disclosure should be able to estimate the eartip fit quality from body-induced sounds boosted by the occlusion effect, and by using a microphone. Moreover, the earphone device of the present disclosure should be able to estimate the eartip fit quality without playing an excitation signal from the headset loudspeakers.

The objective is achieved by the embodiments of the disclosure as described in the enclosed independent claims. Advantageous implementations of the embodiments of the disclosure are further defined in the dependent claims.

A first aspect of the present disclosure provides an earphone device comprising an ear adjustment unit adapted to be adjusted to a user’s ear, the ear adjustment unit comprises an eartip being configured to be at least partially inserted into an ear canal of the user’s ear, a sensor configured to detect a sound signal in the ear canal when the eartip is at least partially inserted into the ear canal, wherein the earphone device further comprises a processor configured to estimate an eartip fit quality based on one or more low-frequency components of the detected sound signal.

The earphone device may be, or may be incorporated in, an electronic device such as an insert-type earphone, an insert-type headphone, etc. The eartip of the eartip adjustment unit may be, for example, a deformable eartip, and may further be at least partially inserted (e.g., positioned) within the ear canal of a user. Furthermore, when the eartip is at least partially inserted into the ear canal of the user, the sensor may detect a sound signal in the ear canal. For example, the sensor may be a microphone and may detect a sound signal which may be a body induced sound. Furthermore, the processor of the earphone device may estimate the eartip fit quality based on one or more low-frequency components of the detected sound signal.

According to some embodiments, the earphone device may comprise at least one circuitry. For example, a first circuitry may comprise the ear adjustment unit comprising the eartip and the sensor. Moreover, a second circuitry of the earphone device may comprise the processor. Furthermore, the first circuitry and the second circuitry may communicate to each other (e.g., wirelessly).

According to some embodiments, the sensor of the earphone device may detect the sound signal in the ear canal. Furthermore, the earphone device may provide (e.g., transmit) the detected sound, the measured audio or some features of it, to another device (e.g., a smartphone). Moreover, the other device may comprise a processor and may estimate the eartip fit quality, etc. Afterwards, the earphone device (e.g., its processor) may obtain the estimated eartip fit quality from the other device.

The earphone device of the first aspect may estimate the eartip fit quality, for example, by performing an eartip fit test that may run in the background, and without the user noticing. Moreover, there might be no need to play an additional sound from the speaker for the eartip fit test.

The earphone device of the first aspect may estimate the eartip fit quality according to the changes in the fit state of the ear adjustment unit, as no excitation needs to be played, picked up, and analyzed.

For example, the earphone device of the first aspect may evaluate the eartip fit quality using a microphone, but without using an excitation signal. This may allow the eartip fit evaluation to run non-invasively in the background each time the user puts the earphone device on. The operation may be based on the occlusion effect, when the eartip is correctly positioned, it creates a tight fit in the ear canal, leading to a boost of low frequencies in the insert microphone. In the absence of an external (and potentially annoying) measurement signal, this low-frequency boost can be observed from the body -induced sounds of the user (blood circulation, breathing, movement). As a result, the eartip fit can be analyzed when the user puts the earphone device on, as a correct fit immediately leads into a boost of low- frequency content observed in the insert microphone. The earphone device may be able to estimate the eartip fit quality also in the presence of external sounds (such as traffic noise), as the external sounds reaching the ear canal via bone conduction will experience the same low-frequency boost due to the occlusion effect when the eartip has a tight fit.

In an implementation form of the first aspect, the processor is configured to estimate the eartip fit quality based on a sound level of the one or more low-frequency components of the detected sound signal, wherein a higher sound level of said one or more low-frequency components correlates to a better eartip fit quality.

In a further implementation form of the first aspect, estimating the eartip fit quality comprises comparing the sound level of the one or more low-frequency components of the detected signal with a sound level of one or more mid-frequency components and/or one or more high-frequency components of the detected signal, wherein the one or more low- frequency components and the one or more mid-frequency components and/or the one or more high-frequency components are obtained at the same time.

In particular, the one or more low-frequency components and the one or more midfrequency components and/or the one or more high-frequency components may be obtained at the same time, at times that are relatively close to each other, etc.

For instance, according to some embodiments, initially, the one or more low-frequency components and the one or more mid-frequency components and/or the one or more high- frequency components may be obtained at the same time. Next, successive short segments may be selected from the obtained one or more low-frequency components and the one or more mid-frequency components and/or the one or more high-frequency components. Afterwards, the selected successive short segments may be compared to each other.

In a further implementation form of the first aspect, the processor is further configured to determine a change in sound level of the one or more low-frequency components of the detected sound signal with respect to a reference sound signal, and estimate the eartip fit quality based on the determined change.

In a further implementation form of the first aspect, the processor is further configured to estimate a bad eartip quality, if the determined change is more than a first threshold value, estimate a medium eartip fit quality, if the determined change is in a range of the first threshold value to a second threshold value, and estimate a good eartip fit quality, if the determined change is less than the second threshold value.

In particular, the first threshold value and the second threshold values may be values depending on the design of the earphone device, and may further be tuned (e.g., adjusted) according to each individual earphone device. In some embodiments, the first threshold value and the second threshold values may also depend on the frequency range where the loss happens, etc.

For example, when the eartip is at least partially inserted into an ear canal of the user’s ear, and when the eartip is properly inserted (i.e. , a good eartip fit quality can be estimated). Moreover, there might be a bass boost, i.e., a large change for low frequencies may occur. Thus, according to some embodiments, a large change for low frequencies may correspond to a good eartip fit quality, and a small change for low frequencies may correspond to a bad eartip fit quality.

In a further implementation form of the first aspect, the eartip is configured to provide an output sound signal, and the processor is further configured to compensate the medium eartip fit quality by applying one or more amplitude changes in one or more frequency regions of the output sound signal, based on the determined change and the reference sound signal.

In a further implementation form of the first aspect, the eartip is configured to provide an output sound signal, and the sensor is configured to detect the sound signal, while the output sound signal is not provided by the eartip In a further implementation form of the first aspect, the one or more low-frequency components of the detected sound signal comprise a body-induced sound of a user of the earphone device.

For example, the earphone device may estimate the eartip fit quality by performing a test based on an occlusion effect. For example, when the eartip is correctly positioned, it creates a tight fit in the ear canal, leading to a boost of low frequencies in the insert microphone. In the absence of an external (e.g., and potentially disturbing to a desired sound being played) measurement signal, this low-frequency boost may be observed from the body- induced sounds of the user such as the blood circulation, the breathing, the movement, etc. Furthermore, the earphone device may analyze the estimated eartip fit quality, when the user insert the eartip into the ear canal as a correct fit may immediately lead into a boost of low-frequency content observed in the insert microphone.

In a further implementation form of the first aspect, the earphone device is further configured to output a user instruction based on the estimated eartip fit quality.

For example, in the case of an incorrect fit, the earphone device may notify the user after the eartip is inserted into the ear canal.

In a further implementation form of the first aspect, the user instruction comprises at least one of: a feedback notification indicating the estimated eartip fit quality; an alarm, if a bad eartip fit quality is estimated; an eartip movement instruction, if a bad eartip fit quality is estimated; an instruction for a change of an eartip size, if a bad eartip fit quality is estimated.

In a further implementation form of the first aspect, the sensor comprises a microphone, and/or a voice pickup sensor, and/or a voice accelerometer.

In a further implementation form of the first aspect, the earphone device further comprising a further sensor arranged in the earphone device or another device and configured to detect a further sound signal outside of the ear canal, wherein the processor is further configured to estimate the eartip fit quality based additionally on the further sound signal. For example, the further sensor may be an outside sensor such as an outside microphone. Technically, the outside sensor might be located on another device, such as a smartphone, etc.

In a further implementation form of the first aspect, the processor is further configured to determine a background noise spectrum based on the detected sound signal and a further background noise spectrum based on the detected further sound signal, determine a spectral difference between the background noise spectrum and the further background noise spectrum, and estimate the eartip fit quality based additionally on the determined spectral difference.

In a further implementation form of the first aspect, the processor is arranged in the eartip.

In some embodiments, it may be possible that the power consumption of the earphone device can be lower, as no excitation signals (audible or inaudible) need to be played for the eartip fit test to work.

In some embodiments, it may be possible that a false positives is not detected (i. e. , a case where the earphone device determines that the eartip is properly in the user’s ear, when in reality it is not), e.g., when the eartip opening is closed by some other object than the ear canal (which could easily happen e.g. in a pocket).

In some embodiments, the earphone device may be used for detecting a case where the earphone device is under technical measurements, e.g., in a head-and-torso-simulator unit instead of being worn by a live person, since the body-induced sounds would be absent in the former case.

A second aspect of the disclosure provides a method for an earphone device comprising an ear adjustment unit adapted to be adjusted to a user’s ear, the method comprising detecting, by a sensor of the ear adjustment unit , a sound signal in an ear canal when an eartip of the ear adjustment unit is at least partially inserted into the ear canal of the user’s ear, and estimating, by a processor of the earphone device, an eartip fit quality based on one or more low-frequency components of the detected sound signal. In an implementation form of the second aspect, the method further comprises estimating the eartip fit quality based on a sound level of the one or more low-frequency components of the detected sound signal, wherein a higher sound level of said one or more low- frequency components correlates to a better eartip fit quality.

In a further implementation form of the second aspect, estimating the eartip fit quality comprises comparing the sound level of the one or more low-frequency components of the detected signal with a sound level of one or more mid-frequency components and/or one or more high-frequency components of the detected signal, wherein the one or more low- frequency components and the one or more mid-frequency components and/or the one or more high-frequency components are obtained at the same time.

In a further implementation form of the second aspect, the method further comprises determining a change in sound level of the one or more low-frequency components of the detected sound signal with respect to a reference sound signal, and estimating the eartip fit quality based on the determined change.

In a further implementation form of the second aspect, the method further comprises estimating a bad eartip quality, if the determined change is more than a first threshold value, estimating a medium eartip fit quality, if the determined change is in a range of the first threshold value to a second threshold value, and estimating a good eartip fit quality, if the determined change is less than the second threshold value.

In a further implementation form of the second aspect, the method further comprises providing, by the eartip, an output sound signal, and compensating, by the processor, the medium eartip fit quality by applying one or more amplitude changes in one or more frequency regions of the output sound signal, based on the determined change and the reference sound signal.

In a further implementation form of the second aspect, the method further comprises providing, by the eartip, an output sound signal, and detecting, by the sensor, the sound signal, while the output sound signal is not provided by the eartip. In a further implementation form of the second aspect, the one or more low-frequency components of the detected sound signal comprise a body-induced sound of a user of the earphone device.

In a further implementation form of the second aspect, the method further comprises outputting a user instruction based on the estimated eartip fit quality.

In a further implementation form of the second aspect, the user instruction comprises at least one of: a feedback notification indicating the estimated eartip fit quality; an alarm, if a bad eartip fit quality is estimated; an eartip movement instruction, if a bad eartip fit quality is estimated; an instruction for a change of an eartip size, if a bad eartip fit quality is estimated.

In a further implementation form of the second aspect, the sensor comprises a microphone, and/or a voice pickup sensor, and/or a voice accelerometer.

In a further implementation form of the second aspect, the method further comprises detecting, by a further sensor arranged in the earphone device or another device, a further sound signal outside of the ear canal, and estimating, by the processor, the eartip fit quality based additionally on the further sound signal.

In a further implementation form of the second aspect, the method further comprises, determining, by the processor, a background noise spectrum based on the detected sound signal and a further background noise spectrum based on the detected further sound signal, determining, by the processor, a spectral difference between the background noise spectrum and the further background noise spectrum, and estimating, by the processor, the eartip fit quality based additionally on the determined spectral difference.

In a further implementation form of the second aspect, the processor is arranged in the eartip.

The method of the second aspect achieves the advantages and effects described for the earphone device of the first aspect. A third aspect of the present disclosure provides a computer program comprising a program code for performing the method according to the second aspect or any of its implementation forms.

A fourth aspect of the present disclosure provides a non-transitory storage medium storing executable program code which, when executed by a processor, causes the method according to the second aspect or any of its implementation forms to be performed.

It has to be noted that all devices, elements, units and means described in the present application could be implemented in the software or hardware elements or any kind of combination thereof. All steps which are performed by the various entities described in the present application as well as the functionalities described to be performed by the various entities are intended to mean that the respective entity is adapted to or configured to perform the respective steps and functionalities. Even if, in the following description of specific embodiments, a specific functionality or step to be performed by external entities is not reflected in the description of a specific detailed element of that entity which performs that specific step or functionality, it should be clear for a skilled person that these methods and functionalities can be implemented in respective software or hardware elements, or any kind of combination thereof.

BRIEF DESCRIPTION OF DRAWINGS

The above described aspects and implementation forms will be explained in the following description of specific embodiments in relation to the enclosed drawings, in which

FIG. 1 depicts a schematic view of an earphone device, according to an embodiment of the disclosure;

FIGS. 2A-2B depict schematic views illustrating when an insert eartip is properly fitted into an ear canal (FIG. 2A), and when an insert eartip is not properly fitted into an ear canal (FIG. 2B); FIG.S 3A-3B depict diagrams illustrating spectrograms obtained from the sensor of earphone device, when the eartip is tightly fitted into the ear (FIG. 3A), and when the fit is leaky (FIG. 3B); and

FIG. 4 depicts a schematic view of a flowchart of a method for an earphone device, according to an embodiment of the disclosure.

DETAILED DESCRIPTION OF EMBODIMENTS

FIG. 1 depicts a schematic view of an earphone device 100, 101, according to an embodiment of the disclosure.

In FIG. 1, in particular, a pair of earphone devices 100, 101 is shown, including a first earphone device 100 comprising an ear adjustment unit 110, for instance, for use in a user's left ear, and a second earphone device 101 comprising an ear adjustment unit 120, for instance, for use with a user's right ear. The first earphone device 100 and the second earphone device 101 may be similar or identical, and may have similar or identical functions as described in this disclosure. Furthermore, the ear adjustment unit 110 and the ear adjustment unit 120 may be similar or identical, and may have similar or identical functions as described in this disclosure.

The earphone device 100, 101 comprising an ear adjustment unit 110, 120 adapted to be adjusted to a user’s ear. The ear adjustment unit 110, 120 comprises an eartip 111, 121 being configured to be at least partially inserted into an ear canal of the user’s ear, and a sensor 112, 122 configured to detect a sound signal in the ear canal when the eartip 111, 121 is at least partially inserted into the ear canal.

The earphone device 100, 101 further comprises a processor 113, 123 configured to estimate an eartip fit quality based on one or more low-frequency components of the detected sound signal.

The earphone device 100, 101 may provide a possibility to create enough low-frequency content into the ear canal using relatively small speakers, since the eartip 111, 121 of the ear adjustment unit 110, 120 creates an enclosed volume between the eartip and eardrum.

Moreover, earphone device 100, 101 may estimate the eartip fit quality based on body- induced sounds boosted by the occlusion effect using the sensor 112, 122 (e.g., a microphone), instead of requiring an excitation signal to be played from the headset loudspeakers.

The earphone device 100, 101 may improve the conventional earphone devices. For example, earphone device 100, 101 may solve a problem in conventional devices. For instance, if the eartip of the ear adjustment unit 110, 120 is not properly inserted into the ear canal, there might be a leak path from the ear canal to the surrounding air. This leak path might considerably reduce the low-frequencies created by the earphone device, and result in a thin sound which lacks bass for the ear in question. In effect, this might greatly degrade the sonic experience of the user. Moreover, it is typically not very easy for the user to consciously know whether the eartip are correctly inserted into the ear canals, apart from the degradation in the sound. As the sonic degradation also depends on the sound content (e.g., a lack of bass might not be very audible on a phone call, but severely affect listening of music). Therefore, the earphone device 100, 101 may estimate the eartip fit quality and may detect whether the eartip is correctly placed into the ear canal, and may further notify the user about it.

The estimated eartip fit quality may also be used in controlling the operation of the earphone device 100, 101 (e.g., whether to play, or pause a music, or go into power save mode, etc.

The earphone device 100, 101 may comprise a processing circuitry (not shown in FIG. 1) configured to perform, conduct or initiate the various operations of the device 100 described herein. The processing circuitry may comprise hardware and software. The hardware may comprise analog circuitry or digital circuitry, or both analog and digital circuitry. The digital circuitry may comprise components such as application-specific integrated circuits (ASICs), field-programmable arrays (FPGAs), digital signal processors (DSPs), or multi-purpose processors. In one embodiment, the processing circuitry comprises one or more processors and a non-transitory memory connected to the one or more processors. The non-transitory memory may carry executable program code which, when executed by the one or more processors, causes the earphone device 100, 101 to perform, conduct or initiate the operations or methods described herein.

References are made from FIG. 2A and FIG. 2B which are schematic views illustrating when an insert eartip is properly fitted into an ear canal (FIG. 2A), and when an insert eartip is not properly fitted into an ear canal (FIG. 2B).

As it can be derived from FIG. 2B, the air path (dashed arrow) allows bass frequencies of the body sounds to escape to the surrounding air, and as a result, the eartip microphone picks up considerably less of them than in the case depicted in FIG. 2A.

The earphone device 100, 101 (e.g., the processor 113, 123) may estimate the eartip fit quality based on a sound level of the low-frequency components of the detected sound signal. Moreover, a higher sound level of said one or more low-frequency components correlates to a better eartip fit quality.

In the case of FIG. 2A, the earphone device 100, 101 (e.g., the processor 113, 123) may estimate a good eartip fit quality. Furthermore, in the case of FIG. 2B, the earphone device 100, 101 (e.g., the processor 113, 123) may estimate a bad eartip fit quality.

References are made from FIG. 3A and FIG. 3B which are diagrams illustrating spectrograms obtained from the sensor 112, 122 (e.g., a microphone), when the eartip 111, 121 is tightly fitted into the ear canal of the user (FIG. 3A), and when the fit is leaky (FIG. 3B).

The earphone device 100, 101 is based on an insert earphone having an insert microphone. The insert microphone may be based on any type of insert microphone, for example, it may be an insert microphone similar to what exists in a feedback headset, a hybrid Active Noise Cancelling (ANC) headset, a non-noise cancelling headphone, etc., without limiting the present disclosure to a specific type of insert microphones or earphone devices.

FIG. 3A depicts the obtained spectrogram 302a from the sensor 112, 122 (e.g., the microphone) of the earphone device 100, 101, when the eartip 111, 121 is tightly fitted into the ear canal of the user. FIG. 3B depicts the obtained spectrogram 302b from the sensor 112, 122 (e.g., the microphone) of the earphone device 100, 101, when the fit is leaky, for example, when the eartip 111, 121 is not tightly fitted into the ear canal of the user.

As it can be derived from FIG. 3A and FIG. 3B, for example, from a comparison of the spectrogram 302a of FIG. 3 A and the spectrogram 302b of FIG. 3B, the enhanced occlusion effect in the case that the eartip 111, 121 is tightly fitted into the ear canal of the user results in a low-frequency boost of around 20 dB.

For ease of comparison, a schematic representation of a part of the spectrogram 302a of FIG. 3A is shown in FIG. 3B, using the dashed curve 301. The dashed curve 301 illustrates the above-mentioned low-frequency boost caused by the enhanced occlusion effect.

The earphone device 100, 101 may detect the difference between the two spectrograms 302a and 302b, in particular the difference, at low frequencies, between the dashed curve 301 and the spectrogram 302b. Moreover, the earphone device 100, 101 may perform an eartip fit test, and may estimate the eartip fit quality, e.g., based on the detected difference.

The previous discussion has so far focused on the sole use of an insert microphone in analyzing the eartip fit quality. However, the earphone device 100, 101 may have a microphone on the outer surface of the unit, to pick up user’s voice. This outer microphone can be used together with the sensor 112, 122.

For example, the earphone device 100, 101 may improve the estimated eartip fit quality based on monitoring the background noise level from the two microphones simultaneously. For example, when the eartip is not inserted to the ear, the noise spectrum should be similar for both microphones (as they are both picking up background noise). Moreover, when the eartip gets inserted to the ear canal however, the low-frequency noise level of the insert microphone increases considerably, while the noise spectrum of the outer microphone remains largely unchanged (still picking up environment noise). This can further increase the accuracy of the estimating the eartip fit quality. Moreover, if the spectral differences of the insert and outside microphones are used in detection, the effect of outside noises to the fit test accuracy is reduced. This is because a change in the outside noise characteristics would be picked up by both microphones rather similarly if the eartip is not inserted into the ear canal. Moreover, since, the signal of interest has relatively low frequencies, it could also be picked up using some other sensor capable of sensing low-frequency vibrations, such as a voice pickup (VPU) sensor, or voice accelerometer, etc.

FIG. 4 shows a method 400 for an earphone device 100, 101 comprising an ear adjustment unit 110, 120 adapted to be adjusted to a user’s ear, according to an embodiment of the disclosure. The method 400 may be carried out by the earphone device 100, 101, as it described above.

The method 400 comprises a step S401 of detecting, by a sensor 112, 122 of the ear adjustment unit 110, 120, a sound signal in an ear canal when an eartip 111, 121 of the ear adjustment unit 110, 120 is at least partially inserted into the ear canal of the user’s ear.

The method 400 further comprises a step S402 of estimating, by a processor 113, 123 of the earphone device 100, 101, an eartip fit quality based on one or more low-frequency components of the detected sound signal.

The present disclosure has been described in conjunction with various embodiments as examples as well as implementations. However, other variations can be understood and effected by those persons skilled in the art and practicing the claimed disclosure, from the studies of the drawings, this disclosure and the independent claims. In the claims as well as in the description the word “comprising” does not exclude other elements or steps and the indefinite article “a” or “an” does not exclude a plurality. A single element or other unit may fulfill the functions of several entities or items recited in the claims. The mere fact that certain measures are recited in the mutual different dependent claims does not indicate that a combination of these measures cannot be used in an advantageous implementation.