Earphone noise reduction structure and method
By designing active noise reduction components and sound playback components in the headphones, combining passive noise reduction and active noise reduction processing, the problem of poor noise reduction effect of existing headphones is solved, and the triple noise reduction effect is achieved, which significantly improves the noise reduction performance and user experience of the headphones.
Patent Information
- Application Number
- CN202510085322.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-01-20
- Publication Date
- 2025-05-16
- Estimated Expiration
- Not applicable · inactive patent
AI Technical Summary
The existing active noise reduction headphones have problems such as ear pressure discomfort, noise reduction waves become noise, sound signal distortion and howling, and passively reduce sound leakage.
A headphone noise reduction structure is adopted, including active noise reduction components and sound playback components. The active noise reduction component is equipped with a call module and a display module. By forming a noise reduction space and listening space, first- and secondary passive noise reduction is used, combined with active noise reduction and active leakage reduction processing, the triple noise reduction effect is achieved.
Effectively reduce the damage to hearing by noise, avoid secondary damage to the eardrum by active noise reduction sound signals, prevent distortion and leakage of sound signals for headphones, and improve the user experience and noise reduction effect of headphones.
Smart Images
Figure CN120018009A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the field of earphone technology, in particular to an earphone noise reduction structure and method. Background Art
[0002] At present, the active noise reduction headphones on the market, whether they are head-mounted or in-ear, share the same listening space for noise reduction, and the sound generator used for noise reduction is also the sound generator for the sound playback of the headphones. The current noise reduction headphones of this type have the following disadvantages: 1. Because the noise reduction waves emitted by the sound generator offset the noise waves in the listening space, they directly face the eardrum, causing ear pressure and discomfort; 2. Because the depth of each person's ear canal is different, the phases of the noise reduction waves and the noise waves when they are transmitted to the eardrum cannot achieve the theoretical difference of 180 degrees, which causes the noise reduction waves to become a new noise and cause damage to hearing; 3. When the headphones adopt the current feed-back or hybrid noise reduction solutions on the market, when the sound waves of some frequencies of the sound played by the headphones are in phase with the corresponding frequency sound waves of the noise, the noise reduction waves will further reduce the amplitude of the corresponding frequency, thereby causing distortion of the sound signal played by the headphones; 4. When the headphones adopt the current feed-back or hybrid noise reduction solutions on the market, due to the existence of the compensation circuit, the headphones are prone to howling, which is extremely harmful to the user's hearing. In addition, the headphones currently on the market all passively reduce sound leakage, and the leakage of sound signals played by the headphones causes an impact on others in public places. Summary of the invention
[0003] In order to solve the above technical problems, the present invention provides a headphone noise reduction structure and method.
[0004] In order to solve the above technical problems, the present invention adopts the following technical solutions:
[0005] A headphone noise reduction structure comprises an active noise reduction component and a sound playing component, wherein the sound playing component is located inside the active noise reduction component, a call module and a display module are arranged outside the active noise reduction component, a noise reduction space is formed between the active noise reduction component and the sound playing component, the sound playing component comprises a sound playing shell and a sound playing sound generator, the sound playing sound generator is mounted on the sound playing shell, a listening space is formed at a contact part between the sound playing component and a human body, an inner side wall is formed at an edge of the sound playing shell, the active noise reduction component comprises a noise reduction shell and a noise reduction sound generator, the noise reduction sound generator is mounted on the noise reduction shell, and an outer side wall is formed at an edge of the noise reduction shell.
[0006] As a further improvement, the active noise reduction component also includes a processing controller, a memory, a first inner pickup, a second inner pickup and an outer pickup, the outer pickup is installed on the outside of the noise reduction shell, the first inner pickup is installed on the inside of the noise reduction shell and is located in the noise reduction space, the second inner pickup is installed on the inside of the sound playing shell and is located in the listening space, and the memory, the first inner pickup, the second inner pickup, the outer pickup, the noise reduction sounder, the sound playing sounder and the display module are respectively connected to the processing controller.
[0007] As a further improvement, a noise reduction method of an earphone noise reduction structure is provided, wherein the earphone is worn on a human ear, and when ambient sound is about to enter the human ear, the outer wall isolates and absorbs the ambient sound, thereby forming a primary passive noise reduction; the active noise reduction component actively reduces the residual ambient sound entering the noise reduction space, and the inner wall isolates and absorbs the residual ambient sound in the noise reduction space, thereby forming a secondary passive noise reduction;
[0008] When the sound playing component is in working state, the sound playing sound generator outputs a sound signal to the listening space. The sound signal is transmitted to the eardrum and outward at the same time. The sound signal transmitted outward is defined as leakage sound. The inner wall isolates and absorbs the sound signal to form a first-level passive reduction of leakage sound. The active noise reduction component actively reduces the leakage of the above-mentioned residual sound signal entering the noise reduction space, and the outer wall isolates and absorbs the above-mentioned residual sound signal in the noise reduction space to form a secondary passive reduction of leakage sound.
[0009] As a further step, the active noise reduction and active sound leakage reduction of the active noise reduction component include:
[0010] When the sound playback component is in a non-working state, the active noise reduction component performs primary detection of the ambient sound: the external microphone collects the current ambient sound signal, then converts it into an electrical signal and transmits it to the processing controller, which processes the electrical signal to detect whether it has voice characteristics; if not, the active noise reduction component maintains the primary detection state of the ambient sound; if yes, further detects its sound pressure level, which is defined as the first external ambient sound and the sound pressure level L1, and then compares L1 with the preset sound pressure level range R B For comparison, the reference sound pressure level L of the active noise reduction component is set B , the preset sound pressure level range R B =L B ±ndB, where n is a preset constant, i.e. L B-Max =L B +ndB,L B-Min =L B -ndB;
[0011] When L1 <L B-MaxWhen L1≥LB-Max, the active noise reduction component maintains the primary detection state of the ambient sound; when L1≥LB-Max, the active noise reduction component performs secondary detection of the ambient sound: the first internal microphone collects the sound signal in the noise reduction space, and then converts it into an electrical signal and transmits it to the processing controller, which processes the electrical signal to detect the voice characteristics of the sound in the noise reduction space; further detects the sound pressure level of the sound in the noise reduction space, which is defined as the residual sound in the first noise reduction space and the sound pressure level L2, and compares L2 with R B Make comparisons;
[0012] When L2 <L B-Max When L2≥L B-Max When the active noise reduction component starts active noise reduction, detects the voice characteristics of the residual sound in the first noise reduction space, and calculates the difference L2-L B , determine the noise reduction depth of the active noise reduction component, and determine the corresponding filter control parameters, use the filter to perform noise reduction processing on the residual sound in the first noise reduction space; output an electrical signal to the noise reduction sounder, the noise reduction sounder converts the electrical signal into a sound signal and outputs it to the noise reduction space, the sound signal and the sound signal of the residual sound in the first noise reduction space cancel each other out, and active noise reduction is achieved.
[0013] As a further improvement, the first inner microphone collects the active noise reduction residual sound signal in the noise reduction space in real time, and then converts it into an electrical signal and transmits it to the processing controller, which processes the electrical signal, detects the voice characteristics and sound pressure level, obtains the sound pressure level L3 of the active noise reduction residual sound, and compares L3 with the preset calibration sound pressure level range R C For comparison, the calibration reference sound pressure level L of the active noise reduction component is set C , the preset calibration sound pressure level range R C =L C ±mdB, where m is a preset constant, i.e. L C-max =L C +mdB,L C-min =L C -mdB;
[0014] When L C-min <L3<L C-max When the active noise reduction component maintains the current noise reduction depth, uses a filter to perform noise reduction processing on the residual sound in the first noise reduction space; outputs an electrical signal to the noise reduction sounder, and the noise reduction sounder converts the electrical signal into a sound signal and outputs it to the noise reduction space, and the sound signal and the sound signal of the residual sound in the first noise reduction space cancel each other out to achieve active noise reduction;
[0015] When L3≤L C-min or L3 ≥ LC-max When the active noise reduction component starts the noise reduction depth calibration, calculates L3 and L C The difference L3-L C , re-determine the noise reduction depth of the active noise reduction component, and determine the corresponding filter control parameters, use the filter to perform noise reduction processing on the residual sound in the first noise reduction space; output an electrical signal to the noise reduction sounder, the noise reduction sounder converts the electrical signal into a sound signal and outputs it to the noise reduction space, the sound signal and the sound signal of the residual sound in the first noise reduction space cancel each other out, and active noise reduction is achieved.
[0016] As a further improvement, when the sound playing component is in working state, the active noise reduction component performs primary detection of the ambient sound: the external microphone of the active noise reduction component collects the current ambient sound signal, and then converts it into an electrical signal and transmits it to the processing controller, the processing controller processes the electrical signal to detect whether it has voice features; if not, the active noise reduction component maintains the primary detection state of the ambient sound; if yes, further detects its sound pressure level, which is defined as the second external ambient sound and the sound pressure level L 1-1 , L 1-1 With the preset sound pressure level range R B For comparison, the reference sound pressure level L of the active noise reduction component is set B , the preset sound pressure level range R B =L B ±ndB, where n is a preset constant, i.e. L B-Max =L B +ndB,L B-Min =L B -ndB;
[0017] When L 1-1 <L B-Max When L1-1≥LB-Max, the active noise reduction system will maintain the primary detection state of the ambient sound; when L1-1≥LB-Max, the active noise reduction component performs secondary detection of the ambient sound: the first internal microphone collects the sound signal in the noise reduction space, and then converts it into an electrical signal and transmits it to the processing controller, which processes the electrical signal, detects the voice characteristics, and further detects the sound pressure level, which is defined as the residual sound in the second noise reduction space and the sound pressure level L 2-1 , the residual sound pressure level L in the second noise reduction space 2-1 and sound pressure level range R B For comparison, when L 2-1 <L B-Max When the active noise reduction component maintains the secondary detection state of the ambient sound;
[0018] When L 2-1 ≥L B-MaxWhen the active noise reduction component starts active noise reduction and active leakage reduction, the residual sound pressure level L in the second noise reduction space is calculated. 2-1 With L B The difference L 2-1 -L B , determine the noise reduction depth of the active noise reduction component, and determine the corresponding filter control parameters, use the filter to perform noise reduction and leakage reduction on the residual sound in the second noise reduction space; output the corresponding electrical signal to the noise reduction sounder of the active noise reduction component, the noise reduction sounder converts the electrical signal into a sound signal and outputs it to the noise reduction space, the sound signal and the signal of the residual sound in the second noise reduction space cancel each other out, and active noise reduction and active leakage reduction are achieved.
[0019] As a further improvement, the first internal microphone collects the active noise reduction and active leakage reduction residual sound signals in the noise reduction space, and then converts them into electrical signals and transmits them to the processing controller, which processes the electrical signals, detects the voice characteristics and sound pressure level, and defines the active noise reduction and active leakage reduction residual sound and the sound pressure level L 3-1 , L 3-1 With the preset calibration sound pressure level range R C For comparison; setting the calibration reference sound pressure level L of the active noise reduction component C , the preset calibration sound pressure level range R C =L C ±mdB, where m is a preset constant, i.e. L C-max =L C +mdB,L C-min =L C -mdB;
[0020] When L C-min <L 3-1 <L C-max When the active noise reduction component maintains the current noise reduction depth, uses a filter to perform noise reduction and leakage reduction on the residual sound in the second noise reduction space; outputs a corresponding electrical signal to the noise reduction sounder of the active noise reduction component, and the noise reduction sounder converts the electrical signal into a sound signal and outputs it to the noise reduction space, and the sound signal and the signal of the residual sound in the second noise reduction space cancel each other out, thereby realizing active noise reduction and active leakage reduction;
[0021] When L 3-1 ≤L C-min or L 3-1 ≥L C-max When the active noise reduction component starts the noise reduction depth calibration, the sound pressure level L of the active noise reduction and active leakage reduction residual sound is calculated. 3-1 With L C The difference L 3-1 -L C, re-determine the noise reduction depth of the active noise reduction component, determine the corresponding filter control parameters, use the filter to perform noise reduction and leakage reduction on the residual sound in the second noise reduction space; output the corresponding electrical signal to the noise reduction sounder of the active noise reduction component, the noise reduction sounder converts the electrical signal into a sound signal and outputs it to the noise reduction space, the sound signal and the signal of the residual sound in the second noise reduction space cancel each other out, and realize active noise reduction and active leakage reduction.
[0022] As a further improvement, the active noise reduction component calibrates the depth of the secondary passive noise reduction by means of a second inner pickup arranged in the listening space, comprising the following steps:
[0023] The sound playing component is suspended, and the sound playing sound generator of the sound playing component is in a silent state; the noise reduction sound generator of the active noise reduction component sends out a calibration sound signal, and the sound pressure level of the calibration sound signal is L4. The calibration sound signal passes through the secondary passive noise reduction formed by the inner wall between the noise reduction space and the listening space, and is transmitted to the listening space. The second inner microphone collects the residual calibration sound signal in the listening space, and then converts it into an electrical signal and transmits it to the processing controller. The processing controller processes the electrical signal, detects its voice characteristics and sound pressure level, and defines it as the residual sound in the listening space and the sound pressure level L5, compares L5 with L4 and calculates their difference L5-L4, determines the depth of the secondary passive noise reduction, and saves the data as a reference when the active noise reduction component performs active noise reduction;
[0024] The depth calibration of the secondary passive noise reduction is completed, the active noise reduction component turns off the depth calibration program of the secondary passive noise reduction, and the sound playing component resumes normal working state.
[0025] Furthermore, the active noise reduction component has a voice recognition function, which distinguishes the ambient sound from the sound signal played by the sound playing component, thereby performing active noise reduction processing on the ambient sound and active leakage reduction processing on the sound signal played by the sound playing component respectively.
[0026] As a further feature, the speech features include sound intensity obtained by performing envelope detection on the sound signal, pitch obtained by performing zero-crossing detection on the sound signal, and timbre, sound length and sound stress obtained by performing intelligent speech recognition on the sound signal.
[0027] Compared with the prior art, the present invention has the following beneficial technical effects:
[0028] When the ambient sound is about to enter the human ear, the outer wall of the noise reduction space on the earphone isolates and absorbs the ambient sound, forming a first-level passive noise reduction; then the active noise reduction component on the earphone actively reduces the residual ambient sound entering the noise reduction space, and finally the inner wall between the noise reduction space and the listening space on the earphone isolates and absorbs the residual ambient sound in the noise reduction space, forming a secondary passive noise reduction, forming a triple noise reduction, which greatly reduces the damage of noise to hearing. At the same time, the active noise reduction is placed outside the listening space to avoid the secondary damage to hearing caused by the active noise reduction sound signal in the existing solution, and also avoids the distortion of the headphone sound signal caused by the superposition of the active noise reduction sound signal and the headphone sound signal. In addition, there is an active leakage reduction function, which can effectively reduce the leakage of the headphone sound signal, thereby reducing the impact of the leakage of the headphone sound signal on others in public places. BRIEF DESCRIPTION OF THE DRAWINGS
[0029] Figure 1 It is a schematic diagram of the cross-sectional structure of the present invention;
[0030] Figure 2 It is a schematic diagram of the wearing state of the present invention;
[0031] Figure 3 It is a schematic diagram of the circuit principle of the present invention.
[0032] Reference numerals:
[0033] Call module 1, sound playing component 2, sound playing sound generator 21, display module 3, active noise reduction component 4, noise reduction sound generator 41, external pickup 42, first internal pickup 43, processing controller 44, second internal pickup 45, noise reduction space 5, external wall 51, listening space 6, internal wall 61, ear canal 7, eardrum 8. DETAILED DESCRIPTION
[0034] The embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and cannot be understood as limiting the present invention.
[0035] In the description of the present invention, it should be understood that if the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise" and the like are involved, the orientation or position relationship indicated is based on the orientation or position relationship shown in the drawings, which is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation of the present invention. In addition, the terms "first" and "second" are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, the meaning of "multiple" is two or more, unless otherwise clearly and specifically defined.
[0036] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected" and "connected" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection. It can be a mechanical connection or an electrical connection. It can be directly connected or indirectly connected through an intermediate medium. It can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.
[0037] Embodiment 1
[0038] refer to Figure 1-3As shown, a headphone noise reduction structure includes an active noise reduction component 4 and a sound playing component 2, the sound playing component 2 is located in the active noise reduction component 4, a call module 1 and a display module 3 are arranged outside the active noise reduction component 4, a noise reduction space 5 is formed between the active noise reduction component 4 and the sound playing component 2, the sound playing component 2 includes a sound playing shell and a sound playing sound generator 21, the sound playing sound generator 21 is mounted on the sound playing shell, the sound playing component 2 forms a listening space with the contact part of the human body, an inner side wall 51 is formed at the edge of the sound playing shell, the active noise reduction component 4 includes a noise reduction shell and a noise reduction sound generator 41, the noise reduction sound generator 41 is mounted on the noise reduction shell, and an outer side wall 61 is formed at the edge of the noise reduction shell. The inner side wall 51 and the outer side wall 61 can respectively form a noise reduction effect. Specifically, the outer wall 51 of the noise reduction space 5 isolates and absorbs the ambient sound, forming a primary passive noise reduction; then the active noise reduction component 4 on the earphone actively reduces the residual ambient sound entering the noise reduction space 5, and finally the inner wall 61 between the noise reduction space 5 and the listening space 6 on the earphone isolates and absorbs the residual ambient sound in the noise reduction space 5, forming a secondary passive noise reduction, and double noise reduction is formed here. Both the sound playing sound generator 21 and the noise reduction sound generator 41 can be speakers.
[0039] When the earphone is worn on the ear, two independent spaces are formed between the single earphone and the human body, including a listening space 6 formed by the innermost earphone and the ear canal 7 and the eardrum 8, and a noise reduction space 5 formed by the earphone and a part of the ear; the listening space 6 is communicatively connected with the noise reduction space 5.
[0040] The active noise reduction component 4 also includes a processing controller 44, a memory, a first inner pickup 43, a second inner pickup 45 and an outer pickup 42, the outer pickup 42 is mounted outside the noise reduction housing, the first inner pickup 43 is mounted inside the noise reduction housing and located in the noise reduction space 5, the second inner pickup 45 is mounted inside the sound playing housing and located in the listening space 6, the memory, the first inner pickup 43, the second inner pickup 45, the outer pickup 42, the noise reduction sounder 41, the sound playing sounder 21 and the display module 3 are respectively connected to the processing controller 44. Multiple first inner pickups, second inner pickups and outer pickups can be provided, and can be selected as microphones.
[0041] The active noise reduction component has multiple modes, including noise reduction mode, normal mode and monitoring mode; it intelligently adjusts the noise reduction depth according to the ambient sound level, or the user can customize the noise reduction depth.
[0042] A sound signal can be obtained through the first inner pickup, the second inner pickup and the outer pickup. The processing controller is used to detect whether the sound signal has speech characteristics, envelope detection is performed on the sound signal to obtain sound intensity, zero-crossing detection is performed on the sound signal to obtain pitch, and intelligent speech recognition is performed on the sound signal to obtain timbre, sound length and sound weight.
[0043] It also includes a power module, which can be assembled in the noise reduction housing or the sound playing housing to provide power for various electronic components.
[0044] Embodiment 2
[0045] refer to Figure 1-3 As shown, a noise reduction method for headphones, the headphones are worn on human ears, when the ambient sound is about to enter the human ears, the outer wall isolates and absorbs the ambient sound, forming a primary passive noise reduction; the active noise reduction component actively reduces the residual ambient sound entering the noise reduction space, and the inner wall isolates and absorbs the residual ambient sound in the noise reduction space, forming a secondary passive noise reduction, the primary passive noise reduction and the secondary passive noise reduction form a dual-stage passive noise reduction, which improves the noise reduction effect. For the noise reduction function, the headphones can be automatically turned on after the human ear is worn, and a noise reduction switch can also be set. The noise reduction mode can be turned on, off, and function switching can be achieved by pressing, pulling, touching, or voice controlling the noise reduction switch. In this embodiment, the noise reduction function is turned on by default after the headphones are worn.
[0046] When the sound playing component 2 is in working state, the sound playing sound generator 21 outputs a sound signal to the listening space 6. The sound signal is transmitted to the eardrum and synchronously transmitted outward. The sound signal transmitted outward is defined as leakage sound. The inner wall 51 isolates and absorbs the sound signal to form a first-level passive reduction of leakage sound. The active noise reduction component 4 actively reduces the residual sound signal entering the noise reduction space 5. The outer wall 61 isolates and absorbs the residual sound signal in the noise reduction space 5 to form a secondary passive reduction of leakage sound. The memory is used to store various environmental sounds and filter control parameter data.
[0047] At the same time, the two effects of noise reduction and sound leakage reduction are utilized to reduce the impact of noise on headphones and improve the user experience of headphones.
[0048] The active noise reduction and active sound leakage reduction of the active noise reduction component include:
[0049] When the sound playing component 2 is in a non-working state, the external microphone 42 collects the current ambient sound signal, and then converts it into an electrical signal and transmits it to the processing controller 44. The processing controller 44 processes the electrical signal to detect whether it has voice characteristics; if not, the active noise reduction component 4 maintains the primary detection state of the ambient sound; if yes, further detects its sound pressure level, which is defined as the first external ambient sound and the sound pressure level L1, and then compares L1 with the preset sound pressure level range R B For comparison, the reference sound pressure level L of the active noise reduction component is set B , L B =40dB, the preset sound pressure level range R B =L B±ndB, where n is a preset constant, n = 3, then L B-Max =43dB, L B-Min =37dB. Of course, n can also be other values, and L B The above settings are not fixed and can be set according to different product models.
[0050] When L1 <L B-Max When L1≥L B-Max When the first internal pickup 43 collects the sound signal in the noise reduction space 5, and then converts it into an electrical signal and transmits it to the processing controller 44. The processing controller 44 processes the electrical signal to detect the voice characteristics of the noise reduction space 5; further detects the sound pressure level of the voice characteristics in the noise reduction space 5, which is defined as the residual sound in the first noise reduction space and the sound pressure level L2, and compares L2 with R B Make comparisons;
[0051] When L2 <L B-Max When L2≥L B-Max When the active noise reduction component 4 starts the active noise reduction, detects the voice characteristics of the residual sound in the first noise reduction space, and calculates the difference L2-L B , determine the noise reduction depth of the active noise reduction component 4, and determine the corresponding filter control parameters, and use the filter to perform noise reduction processing on the residual sound in the first noise reduction space; the processing controller 44 outputs an electrical signal to the noise reduction sound generator 41, and the noise reduction sound generator 41 converts the electrical signal into a sound signal and outputs it to the noise reduction space 5, and the sound signal and the signal of the residual sound in the first noise reduction space cancel each other out to achieve active noise reduction.
[0052] The first internal pickup 43 collects the active noise reduction residual sound signal in the noise reduction space in real time, and then converts it into an electrical signal and transmits it to the processing controller 44. The processing controller 44 processes the electrical signal, detects the voice characteristics, obtains the active noise reduction residual sound, and the sound pressure level L3 of the active noise reduction residual sound. L3 is compared with the preset sound pressure level range R C For comparison; setting the calibration reference sound pressure level L of the active noise reduction component C , the preset calibration sound pressure level range R C =L C ±mdB, where m is a preset constant, i.e. L C-max =L C +mdB,L C-min =L C -mdB;
[0053] When L C-min <L3-1 <L C-max When the active noise reduction component maintains the current noise reduction depth, uses a filter to perform noise reduction and leakage reduction on the residual sound in the second noise reduction space; outputs a corresponding electrical signal to the noise reduction sounder of the active noise reduction component, and the noise reduction sounder converts the electrical signal into a sound signal and outputs it to the noise reduction space, and the sound signal and the signal of the residual sound in the second noise reduction space cancel each other out, thereby realizing active noise reduction and active leakage reduction;
[0054] When L 3-1 ≤L C-min or L 3-1 ≥L C-max When the active noise reduction component starts the noise reduction depth calibration, the sound pressure level L of the active noise reduction and active leakage reduction residual sound is calculated. 3-1 With L C The difference L 3-1 -L C , re-determine the noise reduction depth of the active noise reduction component, determine the corresponding filter control parameters, use the filter to perform noise reduction and leakage reduction on the residual sound in the second noise reduction space; output the corresponding electrical signal to the noise reduction sounder of the active noise reduction component, the noise reduction sounder converts the electrical signal into a sound signal and outputs it to the noise reduction space, the sound signal and the signal of the residual sound in the second noise reduction space cancel each other out, and realize active noise reduction and active leakage reduction.
[0055] When the sound playing component 2 is in working state, the external microphone 42 of the active noise reduction component 4 collects the current environmental sound signal, and then converts it into an electrical signal and transmits it to the processing controller 44, which processes the electrical signal to detect whether it has external voice features; if not, the active noise reduction component 4 maintains the primary detection state of the environmental sound; if yes, it is defined as the second external environmental sound and the sound pressure level is L4, L4 is compared with the reference sound pressure level L in the active noise reduction component. B Preset sound pressure level range R B For comparison, the preset sound pressure level range R B =L B ±ndB, where L B =40dB, where n is a preset constant, n=3, then L B-Max =43dB, L B-Min =37dB. Of course, n can also be other values, and L B The above settings are not fixed and can be set according to different product models.
[0056] When L4 <L B-MaxWhen L4≥L B-Max When the first internal pickup 42 collects the sound signal in the noise reduction space 5, and then converts it into an electrical signal and transmits it to the processing controller 44. The processing controller 44 processes the electrical signal, detects the voice feature, and defines it as the residual sound in the second noise reduction space and the sound pressure level L5, and compares the residual sound pressure level L5 in the second noise reduction space with the sound pressure level range R B For comparison, when L5 <L B-Max When the active noise reduction component 4 maintains the secondary detection state of the ambient sound;
[0057] When L5 ≥ L B-Max When the active noise reduction component 4 starts active noise reduction and active leakage reduction, the residual sound pressure level L5 and L B The difference L2-L B , determine the noise reduction depth of the active noise reduction component 4, and determine the corresponding filter control parameters, use the filter to reduce noise and leakage of the residual sound in the second noise reduction space; output the corresponding electrical signal to the noise reduction sounder 41 of the active noise reduction component, the noise reduction sounder 41 converts the electrical signal into a sound signal and outputs it to the noise reduction space 5, the sound signal and the signal of the residual sound in the second noise reduction space cancel each other out, and active noise reduction and active leakage reduction are achieved.
[0058] In the above, a sound signal is generated and input into the noise reduction space to offset the residual sound signal, thereby achieving the purpose of active noise reduction and active leakage reduction, improving the noise reduction and leakage reduction effects, and improving the user experience of the headphones.
[0059] The first internal pickup 42 collects the active noise reduction and active leakage reduction residual sound signals in the noise reduction space 5, and then converts them into electrical signals and transmits them to the processing controller 44. The processing controller 44 processes the electrical signals and detects the voice features, which are defined as the active noise reduction and active leakage reduction residual sound and the sound pressure level L 3-1 , L 3-1 With R C For comparison; setting the calibration reference sound pressure level L of the active noise reduction component C , the preset calibration sound pressure level range R C =L C ±mdB, where m is a preset constant, i.e. L C-max =L C +mdB,L C-min =L C -mdB;
[0060] When L C-min <L 3-1 <L C-maxWhen the active noise reduction component 4 maintains the current noise reduction depth, and uses a filter to perform noise reduction processing on the residual sound in the second noise reduction space; outputs a corresponding electrical signal to the noise reduction sound generator 41 of the active noise reduction component 4, and the noise reduction sound generator 41 converts the electrical signal into a sound signal and outputs it to the noise reduction space 5, and the sound signal and the signal of the residual sound in the second noise reduction space cancel each other out, thereby realizing active noise reduction and active leakage reduction;
[0061] When L 3-1 ≤L C-min or L 3-1 ≥L C-max When the active noise reduction component 4 starts the noise reduction depth calibration, the sound pressure level L of the active noise reduction and active leakage residual sound is calculated. 3-1 With L C The difference L 3-1 -L C , re-determine the noise reduction depth of the active noise reduction component 4, and determine the corresponding filter control parameters, use the filter to perform noise reduction processing on the residual sound in the second noise reduction space; output the corresponding electrical signal to the noise reduction sounder 41, the noise reduction sounder 41 converts the electrical signal into a sound signal and outputs it to the noise reduction space 5, the sound signal and the signal of the residual sound in the noise reduction space 5 cancel each other out, and realize active noise reduction and active leakage reduction.
[0062] The active noise reduction component 4 calibrates the depth of the secondary passive noise reduction through the second inner pickup 45 arranged in the listening space 6, including the following steps:
[0063] The sound playing component 2 is suspended, and the sound playing sound generator 21 of the sound playing component 2 is in a silent state; the noise reduction sound generator 41 of the active noise reduction component 4 sends a calibration sound signal, and the sound pressure level of the calibration sound signal is L4. The calibration sound signal passes through the secondary passive noise reduction formed by the inner wall 51 between the noise reduction space 5 and the listening space 6, and then is transmitted to the listening space 6. The second inner pickup 45 collects the residual calibration sound signal in the listening space 6, and then converts it into an electrical signal and transmits it to the processing controller 44. The processing controller 44 processes the electrical signal, detects its voice characteristics, and defines it as the residual sound in the listening space and the sound pressure level L5, compares L5 with L4 and calculates their difference L5-L4, determines the depth of the secondary passive noise reduction, and saves the data as a reference when the active noise reduction component performs active noise reduction;
[0064] The depth calibration of the secondary passive noise reduction is completed, the active noise reduction component turns off the depth calibration program of the secondary passive noise reduction, and the sound playing component 2 resumes normal working state.
[0065] By processing the noise reduction space and the listening space separately, both passive noise reduction and active noise reduction can be performed at the same time to improve the sound quality.
[0066] The active noise reduction component 2 has a voice recognition function, which distinguishes the ambient sound from the sound signal, thereby performing active noise reduction processing on the ambient sound and active noise reduction processing on the sound signal respectively.
[0067] The triple noise reduction of the present invention greatly reduces the damage of noise to hearing, and at the same time places the active noise reduction outside the listening space 6, avoiding the secondary damage of the active noise reduction sound signal to the eardrum in the existing solution, and also avoiding the distortion of the headphone sound signal caused by the superposition of the active noise reduction sound signal and the headphone sound signal. In addition, the method also has an active leakage reduction function, which can effectively reduce the leakage of the headphone sound signal, thereby reducing the impact of the headphone sound signal leakage on others in public places, so that the noise is really away from the eardrum, thereby protecting hearing. The method of the present invention can be widely used in various headphone noise reduction.
[0068] It should be noted that the above are only preferred embodiments of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the embodiments, it is still possible for those skilled in the art to modify the technical solutions described in the aforementioned embodiments or to make equivalent substitutions for some of the technical features therein. However, any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.
Claims
1. A headphone noise reduction structure, characterized in that: The invention comprises an active noise reduction component and a sound playing component, wherein the sound playing component is located inside the active noise reduction component, a call module and a display module are arranged on the outside of the active noise reduction component, a noise reduction space is formed between the active noise reduction component and the sound playing component, the sound playing component comprises a sound playing shell and a sound playing sound generator, the sound playing sound generator is mounted on the sound playing shell, a listening space is formed at a contact part between the sound playing component and the human body, an inner side wall is formed at the edge of the sound playing shell, the active noise reduction component comprises a noise reduction shell and a noise reduction sound generator, the noise reduction sound generator is mounted on the noise reduction shell, and an outer side wall is formed at the edge of the noise reduction shell.
2. The headphone noise reduction structure according to claim 1, characterized in that: The active noise reduction component also includes a processing controller, a memory, a first inner microphone, a second inner microphone and an outer microphone. The outer microphone is installed outside the noise reduction shell, the first inner microphone is installed inside the noise reduction shell and is located in the noise reduction space, the second inner microphone is installed inside the sound playing shell and is located in the listening space, and the memory, the first inner microphone, the second inner microphone, the outer microphone, the noise reduction sound generator, the sound playing sound generator, the call module and the display module are respectively connected to the processing controller.
3. A noise reduction method of the headphone noise reduction structure according to claim 2, wherein the headphone is worn by a human ear, characterized in that: When ambient sound is about to enter the human ear, the outer wall isolates and absorbs the ambient sound, forming a primary passive noise reduction; the active noise reduction component actively reduces the residual ambient sound entering the noise reduction space, and the inner wall isolates and absorbs the residual ambient sound in the noise reduction space, forming a secondary passive noise reduction; When the sound playing component is in working state, the sound playing sound generator outputs a sound signal to the listening space. The sound signal is transmitted to the eardrum and outward at the same time. The sound signal transmitted outward is defined as leakage sound. The inner wall isolates and absorbs the sound signal to form a first-level passive reduction of leakage sound. The active noise reduction component actively reduces the leakage of residual sound signals entering the noise reduction space, and the outer wall isolates and absorbs the residual sound signals in the noise reduction space to form a secondary passive reduction of leakage sound.
4. The noise reduction method according to claim 3, characterized in that: The active noise reduction and active sound leakage reduction of the active noise reduction component include: When the sound playback component is in a non-working state, the active noise reduction component performs primary detection of the ambient sound: the external microphone collects the current ambient sound signal, then converts it into an electrical signal and transmits it to the processing controller, which processes the electrical signal to detect whether it has voice characteristics; if not, the active noise reduction component maintains the primary detection state of the ambient sound; if yes, further detects its sound pressure level, which is defined as the first external ambient sound and the sound pressure level L1, and then compares L1 with the preset sound pressure level range R B For comparison, the reference sound pressure level L of the active noise reduction component is set B , the preset sound pressure level range R B =L B ±ndB, where n is a preset constant, i.e. L B-Max =L B +ndB,L B-Min =L B -ndB; When L1 <L B-Max When L1≥L B-Max When the active noise reduction component performs secondary detection of the ambient sound: the first internal microphone collects the sound signal in the noise reduction space, and then converts it into an electrical signal and transmits it to the processing controller, which processes the electrical signal and detects the voice characteristics of the sound in the noise reduction space; further detects the sound pressure level of the sound in the noise reduction space, which is defined as the residual sound in the first noise reduction space and the sound pressure level L2, and compares L2 with R B Make comparisons; When L2 <L B-Max When L2≥L B-Max When the active noise reduction component starts active noise reduction, detects the voice characteristics of the residual sound in the first noise reduction space, and calculates the difference L2-L B , determine the noise reduction depth of the active noise reduction component, and determine the corresponding filter control parameters, use the filter to perform noise reduction processing on the residual sound in the first noise reduction space; output an electrical signal to the noise reduction sounder, the noise reduction sounder converts the electrical signal into a sound signal and outputs it to the noise reduction space, the sound signal and the sound signal of the residual sound in the first noise reduction space cancel each other out, and active noise reduction is achieved.
5. The noise reduction method according to claim 4, characterized in that: The first internal microphone collects the active noise reduction residual sound signal in the noise reduction space in real time, and then converts it into an electrical signal and transmits it to the processing controller, which processes the electrical signal, detects the voice characteristics and sound pressure level, obtains the sound pressure level L3 of the active noise reduction residual sound, compares L3 with the preset calibration sound pressure level range R C For comparison, set the calibration reference sound pressure level L of the active noise reduction component C , the preset calibration sound pressure level range R C =L C ±mdB, where m is a preset constant, i.e. L C-max =L C +mdB,L C-min =L C -mdB; When L C-min <L3<L C-max When the active noise reduction component maintains the current noise reduction depth, the active noise reduction component uses a filter to perform noise reduction processing on the residual sound in the first noise reduction space; Outputting an electrical signal to a noise reduction sounder, the noise reduction sounder converts the electrical signal into a sound signal and outputs it to the noise reduction space, the sound signal and the sound signal of the residual sound in the first noise reduction space cancel each other out, thereby realizing active noise reduction; When L3≤L C-min or L3 ≥ L C-max When the active noise reduction component starts the noise reduction depth calibration, calculates L3 and L C The difference L3-L C , re-determine the noise reduction depth of the active noise reduction component, determine the corresponding filter control parameters, and use the filter to perform noise reduction processing on the residual sound in the first noise reduction space; Output an electrical signal to the noise reduction sounder, the noise reduction sounder converts the electrical signal into a sound signal and outputs it to the noise reduction space, the sound signal and the sound signal of the residual sound in the first noise reduction space cancel each other out to achieve active noise reduction.
6. The noise reduction method according to claim 4, characterized in that: When the sound playing component is in working state, the active noise reduction component performs primary detection of the ambient sound: the external microphone of the active noise reduction component collects the current ambient sound signal, and then converts it into an electrical signal and transmits it to the processing controller, which processes the electrical signal to detect whether it has voice features; if not, the active noise reduction component maintains the primary detection state of the ambient sound; if yes, further detects its sound pressure level, which is defined as the second external ambient sound and the sound pressure level L 1-1 , L 1-1 With the preset sound pressure level range R B For comparison, the reference sound pressure level L of the active noise reduction component is set B , the preset sound pressure level range R B =L B ±ndB, where n is a preset constant, i.e. L B-Max =L B +ndB,L B-Min =L B -ndB; When L 1-1 <L B-Max When L 1-1 ≥L B-Max When the active noise reduction component performs secondary detection of the ambient sound, the first internal microphone collects the sound signal in the noise reduction space, and then converts it into an electrical signal and transmits it to the processing controller, which processes the electrical signal, detects the voice characteristics, and further detects the sound pressure level, which is defined as the residual sound in the second noise reduction space and the sound pressure level L 2-1 , the residual sound pressure level L in the second noise reduction space 2-1 and sound pressure level range R B For comparison, when L 2-1 <L B-Max When the active noise reduction component maintains the secondary detection state of the ambient sound; When L 2-1 ≥L B-Max When the active noise reduction component starts active noise reduction and active leakage reduction, the residual sound pressure level L in the second noise reduction space is calculated. 2-1 With L B The difference L 2-1 -L B , determining the noise reduction depth of the active noise reduction component, and determining the corresponding filter control parameters, and using the filter to perform noise reduction and leakage reduction processing on the residual sound in the second noise reduction space; Output the corresponding electrical signal to the noise reduction sounder of the active noise reduction component, and the noise reduction sounder converts the electrical signal into a sound signal and outputs it to the noise reduction space. The sound signal and the signal of the residual sound in the second noise reduction space cancel each other out, thereby realizing active noise reduction and active leakage reduction.
7. The noise reduction method according to claim 6, characterized in that: The first internal microphone collects the active noise reduction and active leakage reduction residual sound signals in the noise reduction space, and then converts them into electrical signals and transmits them to the processing controller, which processes the electrical signals, detects the voice characteristics and sound pressure level, and defines the active noise reduction and active leakage reduction residual sound and the sound pressure level L 3-1 , L 3-1 With the preset calibration sound pressure level range R C For comparison; setting the calibration reference sound pressure level L of the active noise reduction component C , the preset calibration sound pressure level range R C =L C ±mdB, where m is a preset constant, i.e. L C-max =L C +mdB,L C-min =L C -mdB; When L C-min <L 3-1 <L C-max When the active noise reduction component maintains the current noise reduction depth, and uses the filter to perform noise reduction and leakage reduction processing on the residual sound in the second noise reduction space; Outputting a corresponding electrical signal to the noise reduction sounder of the active noise reduction component, the noise reduction sounder converts the electrical signal into a sound signal and outputs it to the noise reduction space, the sound signal and the signal of the residual sound in the second noise reduction space cancel each other out, thereby realizing active noise reduction and active leakage reduction; When L 3-1 ≤L C-min or L 3-1 ≥L C-max When the active noise reduction component starts the noise reduction depth calibration, the sound pressure level L of the active noise reduction and active leakage reduction residual sound is calculated. 3-1 With L C The difference L 3-1 -L C , re-determine the noise reduction depth of the active noise reduction component, and determine the corresponding filter control parameters, and use the filter to perform noise reduction and leakage reduction processing on the residual sound in the second noise reduction space; Output the corresponding electrical signal to the noise reduction sounder of the active noise reduction component, and the noise reduction sounder converts the electrical signal into a sound signal and outputs it to the noise reduction space. The sound signal and the signal of the residual sound in the second noise reduction space cancel each other out, thereby realizing active noise reduction and active leakage reduction.
8. The noise reduction method according to claim 3, characterized in that: The active noise reduction component calibrates the depth of the secondary passive noise reduction by means of a second inner pickup arranged in the listening space, comprising the following steps: The sound playing component is suspended, and the sound playing sound generator of the sound playing component is in a silent state; the noise reduction sound generator of the active noise reduction component sends out a calibration sound signal, and the sound pressure level of the calibration sound signal is L4. The calibration sound signal passes through the secondary passive noise reduction formed by the inner wall between the noise reduction space and the listening space, and is transmitted to the listening space. The second inner microphone collects the residual calibration sound signal in the listening space, and then converts it into an electrical signal and transmits it to the processing controller. The processing controller processes the electrical signal, detects its voice characteristics and sound pressure level, and defines it as the residual sound in the listening space and the sound pressure level L5, compares L5 with L4 and calculates their difference L5-L4, determines the depth of the secondary passive noise reduction, and saves the data as a reference when the active noise reduction component performs active noise reduction; The depth calibration of the secondary passive noise reduction is completed, the active noise reduction component turns off the depth calibration program of the secondary passive noise reduction, and the sound playing component resumes normal working state.
9. The noise reduction method according to claim 3, characterized in that: The active noise reduction component has a voice recognition function, which distinguishes the ambient sound from the sound signal played by the sound playing component, thereby performing active noise reduction processing on the ambient sound and active leakage reduction processing on the sound signal played by the sound playing component respectively.
10. The noise reduction method according to any one of claims 4 to 9, characterized in that: The speech features include sound intensity obtained by performing envelope detection on the sound signal, pitch obtained by performing zero-crossing detection on the sound signal, and timbre, sound length and sound weight obtained by performing intelligent speech recognition on the sound signal.