Hearing detection device with automatic calibration function and calibration method

Abstract

The present application relates to the technical field of medical devices and biological signal detection, and particularly relates to a hearing detection device with automatic calibration function and a calibration method, comprising an earphone shell, which comprises a left ear cover and a right ear cover, and the left ear cover and the right ear cover are connected through a connecting piece; a loudspeaker unit is arranged inside each ear cover; a calibration microphone is arranged inside each ear cover and faces the sound emitting surface of the loudspeaker unit, and is used for collecting the sound pressure signal emitted by the loudspeaker unit and propagated through the internal space of the ear cover. By integrating the calibration microphone facing the sound emitting surface of the loudspeaker in each ear cover, and executing the automatic calibration program by using the control unit, the multi-frequency point sound calibration can be quickly and automatically completed before use, the deviation is dynamically compensated, the acoustic output of each test is ensured to meet the national audiometer standard, and the test result error caused by the lack of real-time calibration of the traditional equipment is solved.

Description

Technical Field

[0001] This invention relates to the field of medical devices and biosignal detection technology, and in particular to a hearing testing device and calibration method with automatic calibration function. Background Technology

[0002] Currently, in the fields of clinical audiometry and neurophysiological monitoring, the commonly used air conduction hearing test headphones rely primarily on periodic manual calibration to ensure the accuracy of acoustic output, posing a potential risk of cross-infection with repeated use. These devices are typically used only for subjective pure-tone audiometry and cannot simultaneously perform objective auditory nerve function assessments, such as acquiring high-quality EEG signals from the ear canal and periauricular region. This makes the test results susceptible to the influence of the subject's subjective state, and their limited functionality fails to meet the evolving needs of precise clinical diagnosis, infection control, and multifunctional integration.

[0003] Existing hearing testing equipment lacks an integrated, multifunctional, intelligent testing system capable of automatically performing acoustic calibration before each use to ensure the accuracy and reliability of output sound intensity and effectively prevent cross-infection. This technical problem directly leads to insufficient accuracy of test results, difficulties in infection control, and limited clinical applicability of the equipment, becoming a key bottleneck restricting the development of integrated and precise hearing and neuroelectrophysiological testing. Summary of the Invention

[0004] To overcome the above shortcomings, this invention provides a hearing testing device and calibration method with automatic calibration function, aiming to improve the problems of existing hearing testing equipment that cannot automatically perform accurate acoustic calibration before each use, pose a risk of cross-infection, and cannot simultaneously perform objective auditory nerve function testing.

[0005] In a first aspect, the present invention provides the following technical solution: a hearing testing device with automatic calibration function, comprising: The earphone housing includes a left earcup and a right earcup, which are connected by a connector; Speaker units, which are located inside each earcup; A calibration microphone, which is located inside each earcup and faces the sound-emitting surface of the speaker unit, is used to collect the sound pressure signal emitted by the speaker unit and propagated through the internal space of the earcup; The cross-infection prevention component includes a medical rubber ear pad that can be detachably installed on the contact surface of each earmuff and a disposable antibacterial sticker that can be attached to the outer surface of the rubber ear pad; The in-ear signal acquisition module is connected to the left earmuff and the right earmuff in a pluggable manner. Each in-ear signal acquisition module includes a flexible probe body, at least three dry electrodes disposed on the probe body, and a hollow acoustic channel penetrating the probe body. A control and communication unit is disposed inside the earphone housing and is electrically connected to the speaker unit, the calibration microphone and each of the in-ear signal acquisition modules; The control and communication unit is configured to: execute an automatic calibration program, control the speaker unit to sequentially output multiple preset frequency test pure tones, collect corresponding actual sound pressure signals through the calibration microphone, determine the actual hearing level based on the actual sound pressure signals, compare the actual hearing level with the standard hearing level, and dynamically adjust the signal driving the speaker unit according to the comparison result.

[0006] Preferably, the disposable antibacterial sticker is made of medical non-woven fabric or PET film, and its surface is coated with a silver ion or quaternary ammonium salt antibacterial coating. The surface of the medical rubber ear pad is provided with an annular positioning groove structure for guiding and positioning the disposable antibacterial sticker.

[0007] Preferably, the medical rubber ear pads are detachably connected to the left and right earmuffs via a snap-fit ​​mechanism.

[0008] Preferably, the at least three dry electrodes in the in-ear signal acquisition module include: The first electrode is located at the foremost end of the probe body; The second electrode is disposed on the side of the probe body and located behind the first electrode; The third electrode is located at the rear of the probe body and behind the second electrode.

[0009] Preferably, the diameter of the hollow acoustic channel is not less than 3mm.

[0010] Preferably, the control and communication unit includes a Bluetooth module and / or a Wi-Fi module.

[0011] Preferably, the control and communication unit is further configured to generate and store a calibration report after completing automatic calibration.

[0012] Preferably, in the control and communication unit, the step of dynamically adjusting the signal driving the speaker unit based on the comparison result specifically includes: S1. Calculate the deviation between the actual hearing level and the standard hearing level at the current frequency; S2. Based on the deviation value, determine the driving voltage adjustment amount corresponding to the current frequency according to the pre-stored compensation relationship model; S3. Adjust the amplitude of the drive signal output to the speaker unit corresponding to the current frequency according to the drive voltage adjustment amount; S4. Repeat steps S1 to S3 until the deviation between the actual hearing level and the standard hearing level at the current frequency is within the preset allowable error range, and then switch to the next preset frequency to continue the calibration.

[0013] Secondly, the present invention provides the following technical solution: a calibration method for a hearing testing device with automatic calibration function, the method comprising: In response to a calibration trigger command, the speaker unit is controlled to sequentially output multiple preset frequency test pure tones; For each output test pure tone, the sound pressure signal generated by that test pure tone is acquired through the calibration microphone; Based on the collected sound pressure signals, the actual hearing level corresponding to each test pure tone is determined; Compare the actual hearing level corresponding to each test pure tone with the standard hearing level at the same frequency; Based on the comparison results, the driving signal used to drive the speaker unit to output the corresponding test pure tone is dynamically adjusted so that the actual hearing level approaches the standard hearing level.

[0014] The present invention has the following beneficial effects: 1. In this invention, by integrating a calibration microphone facing the speaker's sound-emitting surface into each earcup and using a control unit to execute an automatic calibration program, multi-frequency acoustic calibration can be completed quickly and automatically before use, dynamically compensating for deviations and ensuring that the acoustic output of each test meets the national audiometer standard. This solves the test result error caused by the lack of real-time calibration in traditional equipment.

[0015] 2. This invention employs a combination of detachable medical rubber ear pads and disposable antibacterial stickers to achieve physical isolation of the earphone contact surface. Only the sticker needs to be replaced after each use, and the ear pads can be repeatedly disinfected. This design not only meets strict hospital infection control standards but also ensures ease of use and cost-effectiveness, making it particularly suitable for high-frequency, multi-patient clinical screening scenarios.

[0016] 3. In this invention, a pluggable in-ear signal acquisition module is used to acquire periauricular / ear canal EEG signals with a high signal-to-noise ratio using at least three built-in dry electrodes while ensuring normal sound conduction to the tympanic membrane. This allows a single device to not only perform subjective pure-tone audiometry but also simultaneously conduct objective neurological function assessments such as auditory evoked potentials, achieving integrated subjective and objective hearing assessment. Attached Figure Description

[0017] Figure 1 This is a three-dimensional structural diagram of the hearing detection device with automatic calibration function proposed in this invention. Figure 2This is a schematic diagram of the system architecture of the hearing detection device with automatic calibration function proposed in this invention; Figure 3 This is a schematic flowchart of the calibration method for the hearing testing device with automatic calibration function proposed in this invention.

[0018] The components include: 1. Earphone shell; 101. Left earcup; 102. Right earcup; 2. In-ear signal acquisition module; 3. Medical rubber ear pads; 4. Disposable antibacterial stickers; and 5. Connectors. Detailed Implementation

[0019] The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0020] Example 1: In a first embodiment of the present invention, the present invention provides a hearing testing device with automatic calibration function, such as... Figure 1 As shown, it includes: The earphone housing 1 includes a left earcup 101 and a right earcup 102, which are connected by a connector 5. Speaker units, which are located inside each earcup; A calibration microphone, which is located inside each earcup and faces the sound-emitting surface of the speaker unit, is used to collect the sound pressure signal emitted by the speaker unit and propagated through the internal space of the earcup; The cross-infection prevention component includes a medical rubber ear pad 3 that can be detachably installed on the contact surface of each ear cup and a disposable antibacterial sticker 4 that can be attached to the outer surface of the rubber ear pad; The in-ear signal acquisition module 2 is connected to the left earmuff 101 and the right earmuff 102 in a pluggable manner. Each in-ear signal acquisition module 2 includes a flexible probe body, at least three dry electrodes disposed on the probe body, and a hollow acoustic channel penetrating the probe body. A control and communication unit is located inside the earphone housing 1 and is electrically connected to the speaker unit, calibration microphone and each in-ear signal acquisition module 2; The control and communication unit is configured to: execute an automatic calibration program, control the speaker unit to output multiple preset frequency test pure tones in sequence, collect the corresponding actual sound pressure signals through the calibration microphone, determine the actual hearing level based on the actual sound pressure signals, compare the actual hearing level with the standard hearing level, and dynamically adjust the signal driving the speaker unit according to the comparison results.

[0021] Specifically, the earphone housing 1 constitutes the main structure of the device, including a left earcup 101 and a right earcup 102. The left earcup 101 and the right earcup 102 are connected by a connector 5, which is typically an adjustable headband or an arc-shaped bracket to accommodate different user head shapes. Both the left earcup 101 and the right earcup 102 have independent speaker units inside, used to output test sound signals to the user's ears. To enable automatic calibration, a calibration microphone is installed inside both the left earcup 101 and the right earcup 102. This calibration microphone is precisely positioned near and facing the sound-emitting surface of the corresponding speaker unit. Its core function is to acquire, in real time, the sound pressure signal emitted by the speaker unit on that side and propagating within the sealed or semi-sealed space inside the earcup, thereby directly monitoring the actual output acoustic characteristics of the speaker. The cross-infection prevention component is a key part of ensuring safe clinical use, and it mainly includes medical rubber ear pads 3 and disposable antibacterial stickers 4. The medical rubber ear pads 3 are securely attached to the annular surfaces of the left earcup 101 and right earcup 102 that come into contact with the user's skin via snaps or other detachable means. The outer surface of the medical rubber ear pads 3 typically has annular positioning grooves or indentations to guide and secure the disposable antibacterial stickers 4. The disposable antibacterial stickers 4 are made of medical-grade non-woven fabric or PET film, with a silver ion or quaternary ammonium salt antibacterial coating on the skin-facing side. Before each test for a different user, healthcare personnel simply remove and discard the old disposable antibacterial sticker 4 and replace it with a new one. The medical rubber ear pads 3 can be retained and periodically disinfected, thus achieving a combination of physical isolation and efficient disinfection. The intra-ear signal acquisition module 2 is the core component for achieving objective auditory nerve function detection. It is independently connected to the lower or inner side of the left earcup 101 and right earcup 102 via pluggable connections, such as through standardized electrical connectors and mechanical slots. Each intra-ear signal acquisition module 2 includes a flexible probe body made of biocompatible silicone or other flexible materials to adapt to the complex shape of the ear canal and auricle, improving wearing comfort. At least three dry electrodes are disposed on the probe body. In a preferred embodiment, these include: a first electrode located at the foremost end of the probe body, corresponding to the position contacting the bottom of the concha during wear; a second electrode located on the side of the probe body and behind the first electrode, corresponding to the position contacting the antihelix region of the tragus during wear; and a third electrode located at the rear of the probe body and behind the second electrode, corresponding to the position contacting the mastoid process extension region during wear. Meanwhile, a hollow acoustic channel with a diameter of not less than 3 mm runs through the entire axis of the probe body, ensuring that the sound emitted from the speaker unit can pass through the channel unimpeded to the user's external auditory canal and reach the tympanic membrane, so as not to affect normal hearing test while collecting electrophysiological signals. The control and communication unit is integrated inside the earphone housing 1, typically located within the headband or one of the earcups. This unit is electrically connected via internal circuitry to the left and right speaker units, calibration microphones, and two in-ear signal acquisition modules 2. At the heart of the control and communication unit is a microcontroller, which runs an automatic calibration program and signal processing algorithms. The unit also integrates at least one wireless communication module, either Bluetooth or Wi-Fi, as well as necessary storage chips. The automatic calibration procedure executed by the control and communication unit follows the following process and algorithm: First, in response to a power-on signal or a calibration command triggered by the user via the host computer software, the control and communication unit controls the speaker unit to sequentially output test pure tones at frequencies of 125Hz, 250Hz, 500Hz, 1000Hz, 2000Hz, 4000Hz, and 8000Hz, according to the international standard IEC 60645-1. For each output test pure tone, the calibration microphone simultaneously acquires its corresponding actual sound pressure level (SPL) signal. Based on this SPL signal, the control and communication unit determines the actual hearing level at that frequency using a pre-stored SPL-to-hearing level (HL) conversion relationship. Subsequently, the calculated actual hearing level is compared with the standard hearing level at that frequency to calculate the deviation value.

[0022] The core compensation process is based on a pre-stored compensation relationship model. This model describes the relationship between the driving voltage V and the output sound pressure level SPL, and can be approximately represented as a linear model: ; Where k(f) is the gain coefficient related to frequency f, and b(f) is the offset related to frequency f. When there is a deviation ΔHL, the required target drive voltage adjustment ΔV can be derived from the model, and the compensation can be calculated using the following formula: ; in, Here, Δf represents the small deviation of the system under the influence of other factors. Based on the calculated ΔV, the control and communication unit dynamically adjusts the amplitude of the drive signal corresponding to the current frequency output to the speaker unit. The aforementioned process of data acquisition, comparison, calculation, and adjustment will be performed iteratively until the deviation between the actual hearing level and the standard hearing level at the current frequency stabilizes within a preset allowable error range, such as ±2dB. Afterward, the system automatically switches to the next preset frequency and repeats the entire process until all preset frequency points have been calibrated. Once calibration is complete, the control and communication unit will generate a digital report containing data before and after calibration for each frequency point, which will be stored in the built-in storage chip and can also be uploaded to the host computer via a wireless module.

[0023] Furthermore, the disposable antibacterial sticker 4 is made of medical non-woven fabric or PET film, and its surface is coated with silver ion or quaternary ammonium salt antibacterial coating. The surface of the medical rubber ear pad 3 is provided with an annular positioning groove structure for guiding and positioning the disposable antibacterial sticker 4.

[0024] Furthermore, the medical rubber ear pads 3 are detachably connected to the left earmuff 101 and the right earmuff 102 via a snap-fit ​​mechanism.

[0025] Specifically, the disposable antibacterial sticker 4 is made of medical nonwoven fabric or PET film, both of which have good biocompatibility, flexibility, and liquid barrier properties. On the skin-facing side of the disposable antibacterial sticker 4, a silver ion or quaternary ammonium salt antibacterial coating is applied. This coating continuously releases antibacterial active ingredients during sticker use, effectively inhibiting or killing common pathogenic microorganisms attached to its surface, thereby achieving active antibacterial protection of the contact surface. On the outer surface of the medical rubber ear pad 3 that contacts the skin, a ring-shaped positioning groove is precisely machined. The contour of this positioning groove matches the shape and size of the disposable antibacterial sticker 4. During use, the edge of the disposable antibacterial sticker 4 can be precisely embedded or aligned into this ring-shaped positioning groove. This structural design serves two main purposes: first, it guides the application of the disposable antibacterial sticker 4 to the correct position quickly and accurately; second, it positions and secures the sticker, preventing it from shifting or falling off due to user activity or sweat during use, thus ensuring the effectiveness and stability of the isolation. The positioning groove structure is widely used in various fields, therefore its specific construction will not be described in detail here. The medical rubber earpad 3 is detachably connected to the main body of the left earcup 101 and the right earcup 102 via a snap-fit ​​mechanism. Specifically, a protruding snap head is provided on the inner edge of the medical rubber earpad 3, and a matching snap groove is provided at the corresponding position on the contact surface of the left earcup 101 and the right earcup 102. During installation, the snap head of the medical rubber earpad 3 is aligned with the snap groove on the earcup and pressure is applied to achieve a secure fastening. During disassembly, the edge of the medical rubber earpad 3 is pried open slightly from a specific direction to disengage the snap head from the snap groove, thereby removing the medical rubber earpad 3 as a whole. This connection method makes the installation and removal of the medical rubber earpad 3 tool-free, simple, and quick, facilitating thorough cleaning and disinfection, such as wiping with medical alcohol or performing low-temperature plasma sterilization, to ensure its reusability and hygiene safety.

[0026] Furthermore, the at least three dry electrodes in the in-ear signal acquisition module 2 include: The first electrode is located at the very front end of the probe body; The second electrode is located on the side of the probe body and behind the first electrode; The third electrode is located at the rear of the probe body and behind the second electrode.

[0027] Furthermore, the diameter of the hollow acoustic channel is not less than 3mm.

[0028] Specifically, the intra-ear signal acquisition module 2 includes at least three dry electrodes, the number and position of which are optimized to acquire electroencephalogram (EEG) signals, especially auditory evoked potential (AEP) signals, from the periauricular and ear canal regions in a non-invasive manner with a high signal-to-noise ratio. These electrodes are directly disposed on the surface of the flexible probe body of the intra-ear signal acquisition module 2, making direct contact with the skin without the need for conductive gel. The first electrode is located at the very tip of the probe body. When the intra-ear signal acquisition module 2 is worn correctly, the position of this first electrode corresponds to and closely contacts the bottom region of the concha of the human ear. This position is close to the anatomical location of the auditory nerve, which is beneficial for acquiring strong near-field signals of auditory evoked neural electrical activity, serving as the primary signal acquisition electrode. The second electrode is located on the side of the probe body, specifically behind the first electrode. Its placement corresponds to the area between the tragus and the antihelix. This area has stable subcutaneous bone structure and relatively low background noise for electrical signals; therefore, the second electrode is preferably used as a reference electrode to provide a stable voltage reference point for the signal acquired by the first electrode, thereby eliminating common-mode interference. The third electrode is located at the rear of the probe body, specifically behind the second electrode. Its placement extends to the vicinity of the mastoid region. The third electrode can serve as a ground electrode or an auxiliary reference electrode. Its main function is to further reduce system noise, improve the common-mode rejection ratio of signal acquisition, and ensure the stability and clarity of the acquired bioelectrical signals. These three electrodes are connected to the signal preprocessing circuit inside the in-ear signal acquisition module 2 via a flexible circuit. Finally, the weak bioelectrical signals acquired are transmitted to the control and communication unit inside the earphone shell 1 for amplification, filtering, and digital processing via a connector. A hollow acoustic channel, extending axially through the probe body, has a diameter of no less than 3 mm. This size ensures that the channel's acoustic impedance is sufficiently low, so that sound emitted from the speaker unit, covering the main hearing test frequency range, does not experience significant attenuation or frequency distortion as it passes through the channel. Sound enters the external auditory canal unimpeded through this channel, ensuring that the acoustic stimulation for the hearing test is effectively transmitted to the tympanic membrane. This allows for continuous, synchronous acquisition of high-quality EEG signals without affecting the standard pure-tone audiometry test.

[0029] Furthermore, the control and communication unit includes a Bluetooth module and / or a Wi-Fi module.

[0030] Furthermore, the control and communication unit is also configured to generate and store a calibration report after automatic calibration is completed.

[0031] Specifically, the control and communication unit integrates a wireless communication module, which is one or a combination of Bluetooth and Wi-Fi modules. The Bluetooth module preferably uses Bluetooth Low Energy technology to establish point-to-point short-range wireless connections with mobile terminal devices, such as smartphones, tablets, or dedicated handheld controllers. The Wi-Fi module is used to connect the device to a local area network or the internet, enabling data exchange with remote servers, cloud-based medical platforms, or hospital information systems. The wireless communication module allows the device to wirelessly transmit real-time collected hearing test data, EEG signals, and calibration data to a host computer for analysis, display, and storage. Simultaneously, it receives control commands from the host computer, such as starting a test, selecting a mode, and triggering calibration, thus achieving wireless and intelligent operation of the device. The control and communication unit is also configured to automatically generate a digital calibration report and store it in its internal non-volatile memory chip after completing all steps of the aforementioned automatic calibration procedure. This calibration report includes at least the following information: the date and time of calibration execution, the target standard hearing level for each preset frequency point, the initial actual hearing level before calibration, the final actual hearing level achieved after dynamic adjustment, an indicator of whether each frequency point passed calibration verification, and the overall status of the calibration process. The stored calibration report can be used for subsequent querying, auditing, or as data for medical quality control.

[0032] Furthermore, in the control and communication unit, the step of dynamically adjusting the signal driving the speaker unit based on the comparison results specifically includes: S1. Calculate the deviation between the actual hearing level and the standard hearing level at the current frequency; S2. Based on the deviation value, determine the driving voltage adjustment amount corresponding to the current frequency according to the pre-stored compensation relationship model; S3. Adjust the amplitude of the drive signal output to the speaker unit corresponding to the current frequency according to the drive voltage adjustment amount; S4. Repeat steps S1 to S3 until the deviation between the actual hearing level and the standard hearing level at the current frequency is within the preset allowable error range, and then switch to the next preset frequency to continue the calibration.

[0033] Specifically, the control and communication unit acquires the actual hearing level determined by the signal collected by the calibration microphone at the current calibration frequency. Simultaneously, it reads the corresponding standard hearing level at the same frequency from an internally stored standard hearing level lookup table. The control and communication unit calculates the difference between the two to obtain the hearing level deviation value at the current frequency, denoted as ΔHL. This deviation value ΔHL serves as the quantitative basis for subsequent compensation adjustments. The control and communication unit invokes its internally stored compensation relationship model. This model describes the mathematical relationship between the driving voltage and the output sound pressure level at a specific frequency. In one specific embodiment, this model can be expressed as a linear relationship: SPL = k(f). V+b(f), where SPL represents the output sound pressure level in dB; V represents the driving voltage in volts (V); k(f) is the gain coefficient related to the current frequency f in dB / V; and b(f) is the offset related to the current frequency f in dB. Since there is a definite conversion relationship between hearing level HL and sound pressure level SPL, the deviation value ΔHL can be directly converted into the desired sound pressure level adjustment ΔSPL. Based on the above model, the control and communication unit calculates the driving voltage adjustment ΔV required to compensate for the deviation ΔHL. Specifically, the driving voltage adjustment ΔV can be calculated using the following formula: ΔV=ΔHL / k(f). In a more refined model, a comprehensive frequency response deviation compensation term Δf can be introduced to correct the small frequency response differences of the speaker or microphone itself. In this case, the formula is: ΔV=(ΔHL-Δf) / k(f); where Δf represents the pre-calibrated inherent deviation of the system at the current frequency. The control and communication unit adjusts the amplitude of the digital drive signal, corresponding to the current calibration frequency, that will be output to the speaker unit later, based on the calculated drive voltage adjustment amount ΔV. Specifically, the control and communication unit modifies the digital gain value of the signal at the corresponding frequency in its internal digital signal processor or microcontroller, thereby effectively changing the amplitude of the analog drive voltage applied to the speaker unit after digital-to-analog conversion. The adjusted drive signal is output to the speaker unit, driving it to emit the test pure tone at the same frequency again, but this time the sound intensity has been corrected according to the calculated ΔV. After the speaker unit re-outputs the test pure tone using the adjusted drive signal from the previous cycle, the control and communication unit again acquires the sound pressure signal through the calibration microphone and repeats the above steps. That is, it recalculates the deviation between the new actual hearing level and the standard hearing level, determines a new drive voltage adjustment based on the new deviation, and adjusts the drive signal again. This closed-loop feedback adjustment process continues iteratively. After each iteration, the control and communication unit checks whether the absolute value of the deviation ΔHL at the current frequency is less than or equal to a preset allowable error threshold, such as 2 dB. If the deviation meets this condition, the calibration of the current frequency point is considered complete. The control and communication unit then selects the next frequency point to be calibrated from the preset frequency sequence and, for this new frequency point, executes the complete calibration process from the beginning. This process continues until all frequency points in the preset frequency sequence have been calibrated, and the final deviations are all within the allowable error range. At this point, the entire automatic calibration procedure is considered complete.

[0034] Example 2: A calibration method for a hearing testing device with automatic calibration function, the method comprising: In response to the calibration trigger command, the speaker unit is controlled to output multiple preset frequency test pure tones in sequence; For each output test pure tone, the sound pressure signal generated by that test pure tone is acquired through a calibrated microphone; Based on the collected sound pressure signals, the actual hearing level corresponding to each test pure tone is determined; Compare the actual hearing level corresponding to each test pure tone with the standard hearing level at the same frequency; Based on the comparison results, the driving signal used to drive the speaker unit to output the corresponding test pure tone is dynamically adjusted so that the actual hearing level approaches the standard hearing level.

[0035] Specifically, the calibration trigger command can come from various sources. For example, when the user turns on the device, the control and communication unit automatically generates an internal start calibration command. Alternatively, the user can manually click the "Start Calibration" button through a host computer software interface wirelessly connected to the device, and the host computer software will send an external trigger command to the control and communication unit via Bluetooth or Wi-Fi network. Once the control and communication unit receives a calibration trigger command, it begins executing the calibration method. First, the control and communication unit sequentially controls the speaker units within the left earcup 101 and right earcup 102 to output sound according to a predetermined frequency sequence. This frequency sequence includes at least the key frequency points for the hearing test; in a standard embodiment, this sequence is 125 Hz, 250 Hz, 500 Hz, 1000 Hz, 2000 Hz, 4000 Hz, and 8000 Hz in sequence. The sound output by the speaker units is a pure tone of a single frequency, i.e., the test pure tone. For each specific frequency of the test pure tone output by the speaker unit, a calibration microphone positioned within the same earcup operates synchronously. The calibration microphone is positioned facing the sound-emitting surface of the speaker unit, thus effectively capturing the sound pressure signal generated by the test pure tone emitted by the speaker unit and propagating within the earcup. The calibration microphone converts this sound pressure signal into an analog electrical signal and transmits it to the control and communication unit. After receiving the analog electrical signal from the calibration microphone, the control and communication unit first performs analog-to-digital conversion to convert it into a digital sound pressure level (SPL) signal. Then, the control and communication unit calculates the actual SPL of the test pure tone based on the digital SPL signal. The formula for calculating the SPL is based on the ratio of the effective sound pressure level (Pref) to the reference sound pressure level (P0), and is typically expressed as: SPL = 20. log10(Pref / P0), in dB, where Pref is the effective value of the acquired sound pressure signal and P0 is the standard reference sound pressure, typically 20 micropascals. After obtaining the sound pressure level SPL, the control and communication unit converts the sound pressure level into the hearing level HL according to the correspondence specified in international standards, thereby obtaining the actual hearing level corresponding to the test pure tone; The control and communication unit internally stores standard hearing level values ​​corresponding to various standard frequencies. These standard hearing levels are determined based on international or national standards such as IEC 60645-1. The control and communication unit compares the calculated actual hearing level corresponding to a specific test pure tone with the internally stored standard hearing levels at the same frequency. This comparison involves calculating the difference between the two values. Based on the difference, the control and communication unit initiates a dynamic adjustment process to correct the drive signal. The core of this process is adjusting the parameters of the drive signal used to drive the speaker unit to output the specific test pure tone. The drive signal is typically a voltage signal. The adjustment is based on a pre-stored compensation relationship model, which describes the relationship between the drive voltage V and the output sound pressure level SPL at a specific frequency, and can be approximated as linear: SPL = k(f). V+b(f), where k(f) is the frequency-dependent gain coefficient and b(f) is the frequency-dependent offset. Assuming the deviation between the measured actual hearing level and the standard hearing level is ΔHL, the desired drive voltage adjustment ΔV can be calculated by back-calculation from the model. If other deviation terms are ignored, the simplified calculation is: ΔV=ΔHL / k(f); if the inherent frequency response deviation Δf of the system is considered, the calculation is: ΔV=(ΔHL-Δf) / k(f). After calculating ΔV according to the above formula, the control and communication unit modifies the amplitude of the drive signal corresponding to that frequency output to the speaker unit according to this adjustment amount, for example, by modifying its digital signal amplitude or the reference voltage of the digital-to-analog converter. The adjusted drive signal drives the speaker unit to emit the same test pure tone again, but the sound intensity has been corrected. The aforementioned process of acquisition, determination, comparison, and adjustment is iteratively executed for the test pure tone at the current frequency until the difference between the actual hearing level acquired and calculated based on the new driving signal and the standard hearing level is within a preset allowable error range, such as ±2 dB. Once the calibration at that frequency point is satisfactory, the control and communication unit automatically switches to the next frequency point in the frequency sequence and repeats the entire process. Finally, when all preset frequency points have been traversed and calibrated, the control and communication unit determines that the entire automatic calibration procedure has been completed. This method, through closed-loop feedback control, ensures that the intensity of each test pure tone output by the device automatically and accurately approaches the legally mandated standard hearing level, thereby guaranteeing the accuracy of subsequent hearing tests.

[0036] Finally, it should be noted that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A hearing testing device with automatic calibration function, characterized in that, include: The headphone housing (1) includes a left earcup (101) and a right earcup (102), which are connected by a connector (5); Speaker units, which are located inside each earcup; A calibration microphone, which is located inside each earcup and faces the sound-emitting surface of the speaker unit, is used to collect the sound pressure signal emitted by the speaker unit and propagated through the internal space of the earcup; The cross-infection prevention component includes a medical rubber ear pad (3) that can be detachably installed on each ear cup contact surface and a disposable antibacterial sticker (4) that can be attached to the outer surface of the rubber ear pad. The in-ear signal acquisition module (2) is connected to the left earmuff (101) and the right earmuff (102) in a pluggable manner. Each in-ear signal acquisition module (2) includes a flexible probe body, at least three dry electrodes disposed on the probe body, and a hollow acoustic channel penetrating the probe body. A control and communication unit is disposed inside the earphone housing (1) and electrically connected to the speaker unit, the calibration microphone and each of the in-ear signal acquisition modules (2); The control and communication unit is configured to: execute an automatic calibration program, control the speaker unit to sequentially output multiple preset frequency test pure tones, collect corresponding actual sound pressure signals through the calibration microphone, determine the actual hearing level based on the actual sound pressure signals, compare the actual hearing level with the standard hearing level, and dynamically adjust the signal driving the speaker unit according to the comparison result.

2. The hearing testing device with automatic calibration function according to claim 1, characterized in that, The disposable antibacterial sticker (4) is made of medical non-woven fabric or PET film, and its surface is coated with silver ion or quaternary ammonium salt antibacterial coating. The surface of the medical rubber ear pad (3) is provided with an annular positioning groove structure for guiding and positioning the disposable antibacterial sticker (4).

3. The hearing testing device with automatic calibration function according to claim 1, characterized in that, The medical rubber ear pad (3) is detachably connected to the left ear cover (101) and the right ear cover (102) by means of a snap fastener.

4. The hearing testing device with automatic calibration function according to claim 1, characterized in that, The at least three dry electrodes in the in-ear signal acquisition module (2) include: The first electrode is located at the foremost end of the probe body; The second electrode is disposed on the side of the probe body and located behind the first electrode; The third electrode is located at the rear of the probe body and behind the second electrode.

5. The hearing testing device with automatic calibration function according to claim 1, characterized in that, The diameter of the hollow acoustic channel is not less than 3mm.

6. The hearing testing device with automatic calibration function according to claim 1, characterized in that, The control and communication unit includes a Bluetooth module and / or a Wi-Fi module.

7. The hearing testing device with automatic calibration function according to claim 1, characterized in that, The control and communication unit is also configured to generate and store a calibration report after completing automatic calibration.

8. The hearing testing device with automatic calibration function according to claim 1, characterized in that, In the control and communication unit, the step of dynamically adjusting the signal driving the speaker unit based on the comparison result specifically includes: S1. Calculate the deviation between the actual hearing level and the standard hearing level at the current frequency; S2. Based on the deviation value, determine the driving voltage adjustment amount corresponding to the current frequency according to the pre-stored compensation relationship model; S3. Adjust the amplitude of the drive signal output to the speaker unit corresponding to the current frequency according to the drive voltage adjustment amount; S4. Repeat steps S1 to S3 until the deviation between the actual hearing level and the standard hearing level at the current frequency is within the preset allowable error range, and then switch to the next preset frequency to continue the calibration.

9. A calibration method for a hearing testing device with automatic calibration function, characterized in that, The method, applied to the hearing testing device with automatic calibration function according to any one of claims 1-8, comprises: In response to a calibration trigger command, the speaker unit is controlled to sequentially output multiple preset frequency test pure tones; For each output test pure tone, the sound pressure signal generated by that test pure tone is acquired through the calibration microphone; Based on the collected sound pressure signals, the actual hearing level corresponding to each test pure tone is determined; Compare the actual hearing level corresponding to each test pure tone with the standard hearing level at the same frequency; Based on the comparison results, the driving signal used to drive the speaker unit to output the corresponding test pure tone is dynamically adjusted so that the actual hearing level approaches the standard hearing level.

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