Open Type Earphones

Abstract

An open-type earphone according to an embodiment of the present specification includes an ear hook including a sound generating unit and a first part and a second part connected in sequence, wherein the first part is hung between the user's auricle and head, and the second part extends toward the anterior outer surface of the auricle and is connected to the sound generating unit, thereby attaching the sound generating unit near the ear canal in a position that does not block the ear canal opening, and at least a portion of the sound generating unit is inserted into the cavity of the concha, and the overlap ratio between the area of ​​the sound generating unit projected onto the sagittal plane and the area of ​​the concha cavity projected onto the sagittal plane is 44.01% or more.

Description

[Technical field]

[0001] The present application relates to the technical field of acoustics, and in particular to open-type earphones.

[0002] [Incorporated by reference] This application claims priority to a Chinese application with application number 202211336918.4 filed on October 28, 2022, priority to a Chinese application with application number 202223239628.6 filed on December 1, 2022, and priority to a PCT application with application number PCT / CN2022 / 144339 filed on December 30, 2022, the entire contents of which are incorporated herein by reference. [Background technology]

[0003] With the development of audio output technology, audio devices (e.g., earphones) are widely applied in people's daily life and can be used in combination with electronic devices such as mobile phones, computers, etc., to provide users with an auditory feast. According to the way in which the user wears the audio device, the audio device can usually be divided into head-mounted, ear-hook, in-ear, etc.

[0004] Therefore, it is necessary to provide an open-type earphone that can improve the comfort when worn by the user and has excellent output performance. Summary of the Invention [Means for solving the problem]

[0005] An open-type earphone according to one embodiment of the present specification includes an ear hook including a sound generating unit and a first part and a second part connected in sequence, wherein the first part is hung between the user's auricle and head, and the second part extends toward the anterior outer surface of the auricle and is connected to the sound generating unit, thereby attaching the sound generating unit near the ear canal in a position that does not block the ear canal opening, and at least a portion of the sound generating unit is inserted into the cavity of the concha, and the overlap ratio between the area of ​​the sound generating unit projected onto the sagittal plane and the area of ​​the concha cavity projected onto the sagittal plane is 44.01% or more.

[0006] Another open-type earphone according to one embodiment of the present specification includes an ear hook including a sound generating unit and a first part and a second part connected in sequence, the first part being hung between the user's auricle and head, the second part extending toward the anterior outer surface of the auricle, and the ear hook being connected to the sound generating unit to fix the sound generating unit in a position near the ear canal without blocking the ear canal opening, at least a portion of the sound generating unit being inserted into the concha cavity, and the distance between the projection of the end of the sound generating unit onto the sagittal plane and the projection of the edge of the concha cavity onto the sagittal plane is 16 mm or less.

[0007] Another open-type earphone according to one embodiment of the present specification includes an ear hook including a sound generating unit and a first part and a second part connected in sequence, where the first part is hung between the user's auricle and head, and the second part extends toward the anterior outer surface side of the auricle and is connected to the sound generating unit to fix the sound generating unit in a position near the ear canal without blocking the ear canal opening, at least a portion of the sound generating unit covers the antihelical region, and the overlap rate between the area of ​​the sound generating unit projected onto the sagittal plane and the area of ​​the concha cavity projected onto the sagittal plane is 11.82% or more.

[0008] Yet another open-type earphone according to one embodiment of the present specification includes an ear hook including a sound generating unit and a first part and a second part connected in sequence, the first part being hung between a user's auricle and head, the second part extending toward the anterior outer surface of the auricle, and the ear hook being connected to the sound generating unit to fix the sound generating unit in a position near the ear canal without blocking the ear canal opening, at least a portion of the sound generating unit covering the antihelix, and the distance between the projection of the end of the sound generating unit onto the sagittal plane and the projection of the inner contour of the auricle onto the sagittal plane is 8 mm or less.

[0009] The present application will be further illustrated by exemplary embodiments, which are not limiting and will be described in detail with reference to the drawings, in which like numbers refer to like structures. [Brief description of the drawings]

[0010] [Figure 1] 1 is a schematic diagram of an exemplary ear according to some embodiments of the present disclosure. [Diagram 2] FIG. 1 is an exemplary wearing schematic diagram of an open-type earphone in accordance with some embodiments of the present disclosure. [Diagram 3] 1 is a schematic diagram of an open-type earphone according to some embodiments of the present specification, in which the sound generating unit is inserted into the cavity of the concha. FIG. [Figure 4] FIG. 2 is a schematic diagram of an acoustic model of a similar cavity structure in accordance with certain embodiments of the present disclosure. [Diagram 5] FIG. 1 is an exemplary wearing schematic diagram of an open-type earphone in accordance with some embodiments of the present disclosure. [Figure 6] 1 is a schematic diagram of a similar cavity structure according to some embodiments herein. [Figure 7] 4A-4C are listening index curve diagrams for similar cavity structures with different sized leakage structures, in accordance with certain embodiments herein. [Figure 8]11A-11C are schematic diagrams of exemplary frequency response curves corresponding to different overlap percentages between the projection area of ​​the first projection and the projection area of ​​the user's concha cavity onto the sagittal plane, in accordance with some embodiments of the present specification. [Figure 9] 11A-11C are schematic diagrams of exemplary frequency response curves corresponding to different ratios of a dimension of a first projection along a major axis direction to a dimension of a first projection along a minor axis direction, in accordance with some embodiments of the present specification. [Figure 10] 11 illustrates frequency response curves for different dimensions of the sound generating portion in the thickness direction according to some embodiments of the present disclosure. [Figure 11A] 1A-1D are schematic diagrams of different exemplary engagement positions of an open-type earphone in accordance with the present disclosure with a user's ear canal. [Figure 11B] 1A-1D are schematic diagrams of different exemplary engagement positions of another open earphone in accordance with the present disclosure with a user's ear canal. [Figure 11C] 1A-1C are schematic diagrams of different exemplary engagement positions of further open-type earbuds with a user's ear canal in accordance with the present disclosure. [Figure 12] 13A-13C are schematic diagrams of exemplary frequency response curves corresponding to different distances from the projection of the end of the sound generating unit onto the sagittal plane to the projection of the edge of the cavity of the concha onto the sagittal plane in accordance with some embodiments of the present specification. [Figure 13A] 11A-11C are schematic diagrams of exemplary frequency response curves corresponding to different overlap percentages between the area of ​​the first projection and the area of ​​the projection of the cavity of the concha onto the sagittal plane in accordance with some embodiments of the present specification; [Figure 13B] 11A-11C are schematic diagrams of exemplary frequency response curves corresponding to different distances from the centroid of the first projection to the centroid of the projection of the ear canal onto the sagittal plane in accordance with some embodiments of the present disclosure. [Figure 14] FIG. 13 is an exemplary schematic diagram of an open-type earphone according to some other embodiments of the present disclosure. [Figure 15] 11A-11C are schematic diagrams of example frequency response curves corresponding to different overlap percentages between a first projection and a projection onto the sagittal plane of the cavity of the concha in accordance with some embodiments of the present disclosure; [Figure 16A]FIG. 13 is an exemplary schematic diagram of an open-type earphone according to some other embodiments of the present disclosure. [Figure 16B] FIG. 13 is an exemplary wearing schematic diagram of another open-type earphone in accordance with some embodiments of the present disclosure. [Figure 16C] 13 is an exemplary wearing schematic diagram of a further open-type earphone in accordance with some further embodiments of the present disclosure. [Figure 16D] 1 is an exemplary wearing schematic diagram of yet another open-type earphone in accordance with some embodiments of the present disclosure. [Figure 16E] 13 is an exemplary wearing schematic diagram of yet another open-type earphone in accordance with some embodiments herein. [Figure 17] 16F is a schematic diagram of exemplary frequency response curves corresponding to different distances from the projection of the end of the sound-generating portion in FIG. 16E onto the sagittal plane to the projection of the edge of the cavity of the concha onto the sagittal plane. [Figure 18A] FIG. 11 is a schematic diagram of exemplary frequency response curves corresponding to different overlap percentages between the area of ​​a first projection of the sound-generating unit onto the sagittal plane and the area of ​​the projection of the sound-generating unit onto the sagittal plane of the concha cavity in a wearing scenario in which the sound-generating unit does not enter the concha cavity in accordance with some other embodiments of the present specification. [Figure 18B] FIG. 13 is a schematic diagram of exemplary frequency response curves corresponding to different distances from the centroid of a first projection of the sound-generating unit onto the sagittal plane to the centroid of the projection of the ear canal opening onto the sagittal plane in a wearing scenario in which the sound-generating unit according to some other embodiments of the present specification does not enter the cavity of the concha. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] In order to more clearly describe the technical means of the embodiments of the present application, the drawings necessary for the description of the embodiments will be briefly described below. Obviously, the drawings described below are only examples or parts of the embodiments of the present application, and those skilled in the art can apply the present application to other similar scenarios based on these drawings without creative efforts. Unless otherwise clear from the context or described otherwise, the same symbols in the drawings represent the same structures or operations.

[0012] FIG. 1 is a schematic diagram of an exemplary ear according to some embodiments of the present application. As shown in FIG. 1, the ear 100 may include an external ear canal 101, a concha cavity 102, a concha navicular 103, a triangular fossa 104, an antihelix 105, a scapha 106, a helix 107, an earlobe 108, a crus of the helix 109, an outer contour 1013, and an inner contour 1014. For convenience of explanation, the superior crus of the antihelix 1011, the inferior crus of the antihelix 1012, and the antihelix 105 are collectively referred to as an antihelical region in the embodiments of the present specification. In some embodiments, the support of an audio device by one or more parts of the ear 100 allows the audio device to be stably worn. In some embodiments, parts such as the external ear canal 101, the concha cavity 102, the concha navicular 103, and the triangular fossa 104 have a certain depth and volume in a three-dimensional space, which can meet the wearing needs of the audio device. For example, the acoustic device (e.g., canal-type earphones) may be fitted to the ear canal 101. In some embodiments, the acoustic device may be fitted to a portion of the ear unit 100 other than the ear canal 101. For example, the acoustic device may be fitted to a portion of the ear canal 101, such as the concha 103, the triangular fossa 104, the antihelix 105, the scaphoid fossa 106, the helix 107, or a combination thereof. In some embodiments, the acoustic device may be fitted to a portion of the user's earlobe 108, etc., to improve comfort and reliability when fitted. By fitting the acoustic device and transmitting sound to a portion of the ear unit 100 other than the ear canal 101, the user's ear canal 101 may be "opened". When the user is wearing the acoustic device (open-type earphones), the acoustic device does not block the user's ear canal 101, and the user can receive not only sound from the acoustic device but also sound from the environment (e.g., horn sounds, bicycle bell sounds, voices of people around, traffic control voices, etc.), thereby reducing the probability of traffic accidents. In some embodiments, based on the structure of the ear portion 100, the acoustic device can be designed with a structure that fits the ear portion 100 to realize the placement of the sound generating portion of the acoustic device at different positions on the ear portion.For example, when the acoustic device is an open-type earphone, the open-type earphone may include a suspension structure (e.g., an ear hook) and a sound-generating unit, the sound-generating unit and the suspension structure are physically connected, and the suspension structure may conform to the shape of the pinna so as to place the entire or a part of the structure of the sound-generating unit in front of the crus helix 109 (e.g., the area J surrounded by the dotted line in FIG. 1). Also, for example, when a user wears an open-type earphone, the entire or a part of the structure of the sound-generating unit may contact the outside of the ear canal 101 (e.g., the location of one or more parts such as the crus helix 109, the concha navicular 103, the triangular fossa 104, the antihelix 105, the scaphoid fossa 106, and the helix 107). Also, for example, when a user is wearing open-type earphones, the entire or partial structure of the sound generating unit may be located within a cavity formed by one or more parts of the ear (e.g., the concha cavity 102, the concha nave 103, the triangular fossa 104, etc.) (e.g., region M1 surrounded by dotted lines in Figure 1, including at least the concha cavity 103 and the triangular fossa 104, and region M2 including at least the concha cavity 102).

[0013] Since different users may have individual differences, the ears have different shapes, sizes, and other dimensions. For ease of explanation and understanding, unless otherwise specified, this specification mainly uses an ear model having a "standard" shape and size as a reference to further describe the wearing method of the acoustic device in the ear model in different embodiments. For example, a simulator including a head and its (left and right) ears, such as GRAS KEMAR, HEAD Acoustics, B&K 4128 series, or B&K 5128 series, manufactured based on ANSI: S3.36, S3.25, and IEC: 60318-7 standards, can be used as a reference for wearing the acoustic device, which shows a scenario in which most users normally wear the acoustic device. Taking GRAS KEMAR as an example, the ear simulator may be any of GRAS 45AC, GRAS 45BC, GRAS 45CC, or GRAS 43AG, etc. Taking HEAD Acoustics as an example, the ear simulator may be any of HMS II.3, HMS II.3 LN, HMS II.3LN HEC, etc. In the examples of the present specification, the measured data range is measured based on GRAS 45BC KEMAR, but it should be understood that there may be differences between different head models and between different ear models, so that when using other models, there may be a variation of ±10% in the relevant data range. By way of example only, the reference ear may have relevant features such as a vertical axis dimension of the projection of the pinna onto the sagittal plane being in the range of 55mm to 65mm, and a sagittal axis dimension of the projection of the pinna onto the sagittal plane being in the range of 45mm to 55mm. The projection of the pinna onto the sagittal plane refers to the projection of the edge of the pinna onto the sagittal plane. The edge of the pinna consists of at least the outer contour of the helix, the contour of the earlobe, the contour of the tragus, the intertragal notch, the antitragal apex, the antitragal notch, etc. Therefore, in this application, descriptions such as "worn by a user," "in a worn state," and "in a worn state" may refer to the acoustic device described in this application being worn on the ear portion of the simulator described above.Naturally, taking into account individual differences among different users, the structure, shape, size, thickness, etc. of one or more parts of the ear part 100 may be differentiated for different shapes and dimensions of ear parts, and these differentiated designs may involve characteristic parameters of one or more parts of the audio device (e.g., the sound generating part, ear hook, etc. described below) having different ranges of values ​​to accommodate different ear parts.

[0014] In addition, in the fields of medicine, anatomy, and the like, three basic cutting planes of the human body, the sagittal plane, the coronal plane, and the horizontal plane, and three basic axes, the sagittal axis, the coronal axis, and the vertical axis, can be defined. The sagittal plane refers to a cutting plane perpendicular to the ground along the front-back direction of the body, dividing the human body into two parts, the left and right, the coronal plane refers to a cutting plane perpendicular to the ground along the left-right direction of the body, dividing the human body into two parts, the front and the back, and the horizontal plane refers to a cutting plane parallel to the ground along the up-down direction perpendicular to the body, dividing the human body into two parts, the top and the bottom. Accordingly, the sagittal axis refers to an axis perpendicular to the coronal plane along the front-back direction of the body, the coronal axis refers to an axis perpendicular to the sagittal plane along the left-right direction of the body, and the vertical axis refers to an axis perpendicular to the horizontal plane along the up-down direction of the body. Furthermore, the term "front side of the ear" as used herein refers to the side of the ear that faces the face region of the human body along the sagittal axis. When the ear of the simulator is viewed along the direction of the coronal axis of the human body, a schematic diagram of the front profile of the ear is obtained as shown in FIG.

[0015] The above description of the ear part 100 is for illustrative purposes only and is not intended to limit the scope of the present application. Those skilled in the art can make various changes and modifications based on the description of the present application. For example, some structures of the acoustic device may block a part or the whole of the ear canal 101. These changes and modifications are still within the scope of protection of the present application.

[0016] FIG. 2 is an exemplary schematic diagram of an open-type earphone according to some embodiments of the present specification. As shown in FIG. 2, the open-type earphone 10 may include a sound generating unit 11 and a hanging structure 12. In some embodiments, the open-type earphone 10 may have the sound generating unit 11 attached to a user's body (e.g., the head, neck, or upper torso of a human body) by the hanging structure 12. In some embodiments, the hanging structure 12 may be an ear hook, the sound generating unit 11 is connected to one end of the ear hook, and the ear hook may be shaped to fit the user's ear. For example, the ear hook may have an arc-shaped structure. In some embodiments, the hanging structure 12 may be a clamping structure that fits the user's auricle so that it can be clamped to the user's auricle. In some embodiments, the hanging structure 12 may include, but is not limited to, an ear hook, an elastic band, etc., so that the user can better wear the open-type earphone 10 and prevent it from coming off during use by the user.

[0017] In some embodiments, the sound generating unit 11 may be attached to the user's body, and a speaker may be installed in the sound generating unit 11 to generate sound and input it to the user's ear unit 100. In some embodiments, the open-type earphone 10 may be combined with a product such as glasses, headphones, a head-mounted display, or an AR / VR helmet. In this case, the sound generating unit 11 may be attached near the user's ear unit 100 in a hanging or clamping manner. In some embodiments, the sound generating unit 11 may have a shape such as a circular ring, an ellipse, a (regular or irregular) polygon, a U-shape, a V-shape, or a semicircle so that it can be directly hung on the user's ear unit 100.

[0018] As shown in FIG. 1 and FIG. 2, in some embodiments, when a user wears an open-type earphone 10, at least a part of the sound generating unit 11 may be located in the region J in front of the tragus of the user's ear 100 or in the regions M1 and M2 in the auricle as shown in FIG. 1. Hereinafter, different wearing positions (11A, 11B, 11C) of the sound generating unit 11 will be described in combination as an example. Note that the anterior outer surface of the auricle described in the embodiments of this specification refers to the side of the auricle facing away from the head along the coronal axis, and accordingly, the posterior inner surface of the auricle refers to the side of the auricle facing the human head along the coronal axis. In some embodiments, the sound generating unit 11A is located on the side of the user's ear 100 facing the face region of the human body along the sagittal axis, that is, the sound generating unit 11A is located in the region J in front of the ear 100. Further, a speaker is provided in the housing of the sound generating unit 11A, and the housing of the sound generating unit 11A may be provided with at least one sound output hole (not shown in FIG. 2), and the sound output hole may be located in a side wall of the housing of the sound generating unit facing or adjacent to the user's ear canal 101, and the speaker can output sound to the user's ear canal 101 through the sound output hole. In some embodiments, the speaker may include a diaphragm, and a cavity in the housing of the sound generating unit 11 is divided into at least a front cavity and a rear cavity by the diaphragm, and the sound output hole is acoustically coupled to the front cavity, and the vibration of the diaphragm drives the air in the front cavity to vibrate and generate air-conducted sound, and the air-conducted sound generated in the front cavity is transmitted to the outside through the sound output hole. In some embodiments, the housing of the sound generating unit 11 may further include one or more decompression holes, which may be located in a side wall adjacent to or opposite to the side wall in which the sound emission hole of the housing is located, and the decompression holes are acoustically coupled to the rear cavity, and as the diaphragm vibrates, they drive the air in the rear cavity to vibrate and generate air-conducted sound, and the air-conducted sound generated in the rear cavity is transmitted to the outside through the decompression holes.For example, in some embodiments, the speaker in the sound generating unit 11A can output sounds having a phase difference (e.g., opposite phases) through the sound output hole and the decompression hole, the sound output hole may be located on a side wall of the housing of the sound generating unit 11A facing the user's ear canal 101, and the decompression hole may be located on a side of the housing of the sound generating unit 11 facing away from the user's ear canal 101, in which case the housing functions as a baffle to increase the difference in acoustic distance between the sound output hole and the decompression hole to the ear canal 101, thereby increasing the intensity of the sound in the ear canal 101 and reducing the volume of sound leakage in the far field. In some embodiments, the sound generating unit 11 may have a long axis direction Y and a short axis direction Z that are perpendicular to the thickness direction X and perpendicular to each other. The long axis direction Y can be defined as the direction in which the extension dimension is the largest in the shape of a two-dimensional projection surface of the sound generating unit 11 (for example, a projection of the sound generating unit 11 onto a plane on which its outer surface is located, or a projection onto a sagittal plane) (for example, when the projection shape is rectangular or approximately rectangular, the long axis direction is the length direction of the rectangle or approximately rectangle), and the short axis direction Z can be defined as the direction perpendicular to the long axis direction Y in the projection shape of the sound generating unit 11 onto the sagittal plane (for example, when the projection shape is rectangular or approximately rectangular, the short axis direction is the width direction of the rectangle or approximately rectangle). The thickness direction X can be defined as the direction perpendicular to the two-dimensional projection surface, and for example, coincides with the direction of the coronal axis, both of which face the left-right direction of the body. In some embodiments, when the sound generating unit 11 is inclined in the wearing state, the long axis direction Y and the short axis direction Z are still parallel or approximately parallel to the sagittal plane, the long axis direction Y may have a certain included angle with the direction of the sagittal axis, i.e., the long axis direction Y is also installed at an incline, and the short axis direction Z may have a certain included angle with the direction of the vertical axis, i.e., the short axis direction Z is also installed at an incline, as in the wearing state of the sound generating unit 11B shown in FIG. 2. In some embodiments, the whole or part of the structure of the sound generating unit 11B may enter the cavity of the concha, i.e., the projection of the sound generating unit 11B onto the sagittal plane and the projection of the cavity of the concha onto the sagittal plane have an overlapping portion. For specific details of the sound generating unit 11B, please refer to other parts of this specification, for example, FIG. 3 and the corresponding contents of the specification.In some embodiments, the voice generating unit may be in a horizontal state or an approximately horizontal state when worn, and as shown in the voice generating unit 11C in FIG. 2, the long axis direction Y may coincide or approximately coincide with the direction of the sagittal axis, both of which face the front-back direction of the body, and the short axis direction Z may coincide or approximately coincide with the direction of the vertical axis, both of which face the up-down direction of the body. Note that the voice generating unit 11C being in an approximately horizontal state when worn may indicate that the included angle between the long axis direction and the sagittal axis of the voice generating unit 11C shown in FIG. 2 is within a specific range (for example, 20° or less). In addition, the wearing position of the voice generating unit 11 is not limited to the voice generating unit 11A, the voice generating unit 11B, and the voice generating unit 11C shown in FIG. 2, and may be any position that satisfies the region J, the region M1, or the region M2 shown in FIG. 1. For example, the entire or part of the structure of the voice generating unit 11 may be located in the region J surrounded by the dotted line in FIG. 1. Also, for example, the entire or partial structure of the sound generating unit may contact the location of one or more parts of the external auditory canal 101, such as the crus helicalis 109, the concha 103, the triangular fossa 104, the antihelix 105, the scaphoid fossa 106, and the helix 107. Also, for example, the entire or partial structure of the sound generating unit may be located within a cavity formed by one or more parts of the ear unit 100 (for example, the concha cavity 102, the concha 103, the triangular fossa 104, etc.) (for example, the region M1 surrounded by the dotted line in FIG. 1, including at least the concha 103 and the triangular fossa 104, and the region M2 including at least the concha cavity 102).

[0019] In order to improve the stability of the open-type earphone 10 in the worn state, the open-type earphone 10 can use any one of the following methods or a combination thereof. In method 1, at least a part of the suspension structure 12 is installed in a conforming structure that fits at least one of the rear inner surface of the auricle and the head to increase the contact area between the suspension structure 12 and the ear part and / or the head, thereby increasing the resistance of the open-type earphone 10 to come off from the ear part. In method 2, at least a part of the suspension structure 12 is installed in an elastic structure so that it has a certain amount of deformation in the worn state, and the resistance of the open-type earphone 10 to come off from the ear part is increased by increasing the positive pressure on the ear part and / or the head by the suspension structure 12. In method 3, the suspension structure 12 is installed so that at least a part of it abuts against the ear and / or head when worn, forming a reaction force that presses the ear, and presses the sound generating unit 11 against the front outer surface of the pinna (for example, area M1 and area M2 shown in FIG. 1), thereby increasing the resistance of the open-type earphone 10 to come off from the ear. In method 4, the sound generating unit 11 and the suspension structure 12 are installed so that they sandwich the antihelical area, the area where the concha cavity is located, and the like from the front outer surface and rear inner surface of the pinna when worn, thereby increasing the resistance of the open-type earphone 10 to come off from the ear. In method 5, the sound generating unit 11 or a structure connected thereto is installed so that at least a part of it enters cavities such as the concha cavity 102, the concha navicular 103, the triangular fossa 104, and the navicular fossa 106, thereby increasing the resistance of the open-type earphone 10 to come off from the ear.

[0020] 3, in the worn state, the end FE (also called the free end) of the sound generating unit 11 may enter the cavity of the concha. Preferably, the sound generating unit 11 and the hanging structure 12 may clamp the ear region corresponding to the cavity of the concha from both the front and rear sides, thereby increasing the resistance of the open-type earphone 10 to come off from the ear, and further improving the stability of the open-type earphone 10 in the worn state. For example, the end FE of the sound generating unit is pressed into the cavity of the concha in the thickness direction X. Also, for example, the end FE abuts against the inside of the cavity of the concha in the long axis direction Y and / or the short axis direction Z (for example, abuts against the inner wall of the cavity of the concha facing the end FE). The end FE of the sound generating unit 11 refers to the end of the sound generating unit 11 that is installed opposite the fixed end connected to the hanging structure 12, and is also called the free end. The sound generating unit 11 may be a regular structure or an irregular structure, and here, an end FE of the sound generating unit 11 will be described as an example to further explain the structure. For example, when the sound generating unit 11 has a rectangular parallelepiped structure, the end wall surface of the sound generating unit 11 is a plane, and in this case, the end FE of the sound generating unit 11 is an end side wall installed facing the fixed end of the sound generating unit 11 connected to the hanging structure 12. Also, for example, when the sound generating unit 11 is a sphere, an ellipsoid, or an irregular structure, the end FE of the sound generating unit 11 may indicate a specific region away from the fixed end obtained by cutting the sound generating unit 11 along the YZ plane (a plane formed by the minor axis direction Z and the thickness direction X), and the ratio of the dimension of the specific region along the major axis direction Y to the dimension of the sound generating unit along the major axis direction Y may be 0.05 to 0.2.

[0021] By having at least a part of the sound generating unit 11 enter the cavity of the concha, it is possible to increase the listening volume at the listening position (e.g., the ear canal opening), especially the listening volume of the mid-low frequency, while still maintaining an excellent cancellation effect of sound leakage in the far field. As a mere illustrative explanation, when the whole or part of the structure of the sound generating unit 11 enters the cavity of the concha 102, the sound generating unit 11 and the cavity of the concha 102 form a structure similar to a cavity (hereinafter, abbreviated as a similar cavity structure), and in the embodiment of the specification, the similar cavity structure may be understood as a semi-closed structure surrounded by the side wall of the sound generating unit 11 and the cavity of the concha 102 structure, and the semi-closed structure does not completely seal the listening position (e.g., the ear canal opening) and isolate it from the external environment, but has a leaking structure (e.g., an opening, a gap, a tube, etc.) that acoustically communicates with the external environment. When a user wears the open-type earphone 10, one or more sound emission holes may be provided on the side of the housing of the sound generating unit 11 that is close to the user's ear canal or that faces the user's ear canal, and one or more decompression holes are provided on the other side wall of the housing of the sound generating unit 11 (for example, the side wall that is away from or facing the user's ear canal), and the sound emission holes are acoustically coupled to the front cavity of the open-type earphone 10, and the decompression holes are acoustically coupled to the rear cavity of the open-type earphone 10. Taking the sound generating unit 11 as an example including one sound emission hole and one decompression hole, the sound output from the sound emission hole and the sound output from the decompression hole can be regarded as approximately two sound sources, and these two sound sources have opposite phases of sound and form a dipole, the sound generating unit 11 and the inner wall corresponding to the concha cavity form a similar cavity structure, the sound source corresponding to the sound emission hole is located inside the similar cavity structure, and the sound source corresponding to the decompression hole is located outside the similar cavity structure, forming the acoustic model shown in FIG. 4. 4, the similar cavity structure 402 may include a listening position and at least one sound source 401A. Here, "including" may indicate that at least one of the listening position and the sound source 401A is inside the similar cavity structure 402, or that at least one of the listening position and the sound source 401A is on an edge of the inside of the similar cavity structure 402.The listening position may be equivalent to the ear canal of the ear, may be an acoustic reference point of the ear, such as ERP, DRP, etc., or may be an entrance structure that guides the listener. The sound source 401B is located outside the similar cavity structure 402, and the sound sources 401A and 401B, which are in phase with each other, form a dipole. The dipole radiates sounds into the surrounding space, respectively, to generate interference cancellation of sound waves, thereby achieving a sound leakage cancellation effect. Since the difference in acoustic distance between the two sounds is large at the listening position, the sound cancellation effect is not significant, and the sound heard at the listening position is louder than at other positions. Specifically, since the sound source 401A is surrounded by the similar cavity structure 402, most of the radiated sound reaches the listening position by direct or reflected methods. In contrast, if there is no similar cavity structure 402, most of the sound radiated from the sound source 401A does not reach the listening position. Therefore, by installing the similar cavity structure 402, the volume of the sound reaching the listening position is greatly increased. Also, only a small portion of the anti-phase sound radiated from the anti-phase sound source 401B outside the analogous cavity structure 402 enters the analogous cavity structure 402 through the leakage structure 403 of the analogous cavity structure 402. This corresponds to a secondary sound source 401B' being generated in the leakage structure 403, and the intensity of the secondary sound source 401B' is significantly lower than that of the sound source 401B and also significantly lower than that of the sound source 401A. The sound generated by the secondary sound source 401B' has a weak effect of canceling out the sound generated from the sound source 401A inside the cavity, which can greatly increase the listening volume at the listening position. Regarding sound leakage, the sound source 401A radiating sound to the outside through the cavity leakage structure 403 is equivalent to the secondary sound source 401A' being generated in the leakage structure 403, and since most of the sounds radiated from the sound source 401A are output from the leakage structure 403 and the scale of the similar cavity structure 402 is much smaller (at least one order of magnitude smaller) than the spatial scale for evaluating sound leakage, it is considered that the strength of the secondary sound source 401A' is equivalent to the strength of the sound source 401A. The canceling effect between the sounds generated by the secondary sound source 401A' and the sound source 401B in the external space is equivalent to the canceling effect between the sounds generated by the sound source 401A and the sound source 401B.That is, the similar cavity structure still maintains a certain degree of sound leakage reduction effect.

[0022] In a specific application scenario, the outer wall surface of the housing of the sound generating unit 11 is usually flat or curved, the contour of the user's concha cavity has an uneven structure, and a part or the entire structure of the sound generating unit 11 enters the concha cavity, so that a similar cavity structure communicating with the outside is formed between the sound generating unit 11 and the contour of the concha cavity. Furthermore, by arranging the sound emission hole at a position facing the user's ear canal opening of the housing of the sound generating unit and at a position close to the edge of the concha cavity, and arranging the decompression hole at a position facing away from the ear canal opening of the sound generating unit 11 or away from the ear canal opening, the acoustic model shown in FIG. 4 can be constructed, whereby when the user is wearing the open-type earphones, the listening volume at the user's ear canal opening can be increased and sound leakage in the far field can be reduced.

[0023] In some embodiments, the sound generating part of the open-type earphone may include a transducer and a housing for accommodating the transducer, and the transducer is an element that can receive an electric signal, convert it into an audio signal, and output it. In some embodiments, when distinguished according to frequency, the type of transducer may include a low frequency (e.g., 30Hz-150Hz) speaker, a mid-low frequency (e.g., 150Hz-500Hz) speaker, a mid-high frequency (e.g., 500Hz-5kHz) speaker, a high frequency (e.g., 5kHz-16kHz) speaker, or a full frequency (e.g., 30Hz-16kHz) speaker, or any combination thereof. Here, low frequency, high frequency, etc., only represent a rough range of frequencies, and different application scenarios may have different distinction methods. For example, a crossover frequency can be determined, and the low frequency represents the frequency range below the crossover frequency, and the high frequency represents the frequency range above the crossover frequency. The crossover frequency may be any value within the audible range of the human ear, such as 500Hz, 600Hz, 700Hz, 800Hz, 1000Hz, etc.

[0024] In some embodiments, the transducer may include one diaphragm. When the diaphragm vibrates, sound is emitted from the front and rear sides of the diaphragm, respectively. In some embodiments, a front cavity (not shown) for transmitting sound is provided at a position on the front side of the diaphragm in the housing 120. The front cavity is acoustically coupled to a sound output hole, and sound from the front side of the diaphragm may pass through the front cavity and be emitted from the sound output hole. A rear cavity (not shown) for transmitting sound is provided at a position on the rear side of the diaphragm in the housing 120. The rear cavity is acoustically coupled to a decompression hole, and sound from the rear side of the diaphragm may pass through the rear cavity and be emitted from the decompression hole.

[0025] Here, as shown in FIG. 3, an example is described in which the ear hook is a hanging structure 12. In some embodiments, the ear hook may include a first part 121 and a second part 122 connected in sequence, the first part 121 may be hung between the user's auricle and the head, and the second part 122 extends toward the outside of the ear (the side facing away from the human head along the coronal axis of the ear) and is connected to the sound generating unit 11, thereby mounting the sound generating unit 11 near the user's ear canal in a position that does not block the ear canal opening. In some embodiments, the sound emission hole may be formed in the side wall of the housing facing the auricle, so that the sound generated by the transducer can be guided out of the housing and transmitted to the user's ear canal opening.

[0026] FIG. 5 is an exemplary wearing schematic diagram of an open-type earphone according to some embodiments of the present disclosure.

[0027] As shown in FIGS. 3 and 5, in some embodiments, when a user wears the open-type earphone 10, the sound-generating unit 11 has a first projection onto the sagittal plane (i.e., the plane formed by the T-axis and the S-axis in FIG. 5) along the coronal axis direction R, and the shape of the sound-generating unit 11 may be a regular or irregular three-dimensional shape, and accordingly, the first projection of the sound-generating unit 11 onto the sagittal plane has a regular or irregular shape, for example, the shape of the sound-generating unit 11 is a rectangular parallelepiped, a substantially rectangular parallelepiped, or a rectangular parallelepiped. Considering that the first projection of the sound generating unit 11 onto the sagittal plane may be rectangular or approximately rectangular (e.g., racetrack-shaped) when the sound generating unit 11 is a cylindrical body, and the first projection of the sound generating unit 11 onto the sagittal plane may be irregular in shape, in order to easily explain the first projection, a rectangular area indicated by a solid frame P is defined around the projection of the sound generating unit 11 (i.e., the first projection) shown in FIG. 5, and the centroid O of the rectangular area indicated by the solid frame P can be regarded as approximately the centroid of the first projection. Note that the above description of the first projection and its centroid is merely an example, and the shape of the first projection is related to the shape of the sound generating unit 11 or the mounting situation of the sound generating unit 11 to the ear. In some embodiments, the sound generating unit 11 and the hanging structure 12 may be two independent structures or may be an integrally molded structure. In order to more clearly explain the first projection area of ​​the sound generating unit 11, here, a thickness direction X, a long axis direction Y, and a short axis direction Z are introduced based on the three-dimensional structure of the sound generating unit 11, the long axis direction Y is perpendicular to the short axis direction Z, and the thickness direction X is perpendicular to the plane formed by the long axis direction Y and the short axis direction Z. As a mere example, the process of determining the solid frame P is to determine the two most distant points in the long axis direction Y of the sound generating unit 11, draw first and second line segments parallel to the short axis direction Z passing through these two points, respectively, determine the two most distant points in the short axis direction Z of the sound generating unit 11, draw third and fourth line segments parallel to the long axis direction Y passing through these two points, respectively, and obtain the rectangular area of ​​the solid frame P shown in FIG. 5 by the area formed by each of the above line segments.

[0028] As described above, when a user wears an open-type earphone 10, at least a part of the sound generating unit 11 can enter the user's cavity of the concha to form the acoustic model shown in FIG. 4. Since the sound generating unit 11 cannot be in close contact with the cavity of the concha, a gap is formed, and the gap corresponds to the leak structure 403 shown in FIG. 4. That is, when the open-type earphone is worn and a part or the entire structure of the sound generating unit 11 enters the cavity of the concha, the projection of the sound generating unit 11 onto the sagittal plane and the projection of the cavity of the concha onto the sagittal plane have an overlapping area. Furthermore, the ratio of the overlapping area affects the size of the opening area of ​​the leak structure 403 of the similar cavity structure 402 of the acoustic model shown in FIG. 4. For example, when the overlapping ratio between the sound generating unit 11 and the cavity of the concha is large, the sound generating unit 11 can cover a large area of ​​the cavity of the concha, and at this time, the gap dimension between the sound generating unit 11 and the cavity of the concha is small, that is, the opening area of ​​the leak structure 403 of the similar cavity structure 402 is small. FIG. 6 is a schematic diagram of a similar cavity structure according to some embodiments of the present specification. FIG. 7 is a listening index curve diagram of similar cavity structures with different sizes of leakage structures according to some embodiments of the present specification. As shown in FIG. 6, the opening area of ​​the leakage structure of the similar cavity structure is S, and the area of ​​the similar cavity structure that the included sound source (shown as "+" in FIG. 6) acts directly on is S0. "Acts directly" here refers to the sound emanating from the included sound source acoustically acting directly on the wall surface of the similar cavity structure without passing through the leakage structure. The distance between the two sound sources is d0, and the distance from the center of the opening shape of the leakage structure to the other sound source (shown as "-" in FIG. 6) is L. As shown in FIG. 7, L / d0=1.09 is held, and the larger the relative opening S / S0, the smaller the listening index. The listening index here may refer to the sound pressure level intensity measured at the listening position. This is because the larger the relative opening, the more sound components are directly radiated from the included sound source to the outside, and the less sound reaches the listening position, so the listening volume decreases as the relative opening increases, and the listening index decreases. This means that the larger the opening, the lower the listening volume at the listening position.In some embodiments, in order to guarantee the listening volume at the ear canal opening when the user is wearing the open-type earphone, the overlapping ratio between the area of ​​the first projection of the sound generating unit 11 onto the sagittal plane and the area of ​​the projection of the cavity of the concha onto the sagittal plane (for example, the area surrounded by the dotted frame 1015 in FIG. 5) can be controlled within a specific range to control the size of the opening. Note that in the embodiments of this specification, the overlapping ratio may be understood as the ratio of the overlapping area between the area of ​​the first projection and the area of ​​the projection of the cavity of the concha onto the sagittal plane to the area of ​​the projection of the cavity of the concha onto the sagittal plane.

[0029] 8 is a schematic diagram of an exemplary frequency response curve corresponding to different overlapping ratios between the area of ​​the first projection of the sound generating unit 11 on the sagittal plane and the area of ​​the projection of the user's concha on the sagittal plane, according to some embodiments of the present specification. In FIG. 8, the horizontal axis indicates frequency (unit: Hz), and the vertical axis indicates frequency response (unit: dB) at the ear canal opening corresponding to different overlapping ratios. As can be seen from FIG. 8, when the user wears an open-type earphone and at least a part of the structure of the sound generating unit 11 covers the concha, i.e., when the first projection of the sound generating unit 11 on the sagittal plane and the projection of the concha on the sagittal plane have an overlapping area, the listening volume at the ear canal opening of the user is significantly increased, especially within the mid-low frequency range, compared to when the first projection and the projection of the concha on the sagittal plane do not have an overlapping area (overlap ratio is 0%). In some embodiments, in order to improve the listening effect when the user wears the open-type earphone, the overlapping ratio between the area of ​​the first projection of the sound generating unit 11 on the sagittal plane and the area of ​​the projection of the user's concha on the sagittal plane may be 9.26% or more. As shown in FIG. 8, as the overlapping ratio between the area of ​​the first projection of the sound generating unit 11 on the sagittal plane and the area of ​​the projection of the user's concha on the sagittal plane increases, the increase in the listening volume at the mouth of the user's ear canal also becomes stronger, and in particular, when the overlapping ratio between the area of ​​the first projection and the area of ​​the projection of the user's concha on the sagittal plane is increased from 36.58% to 44.01%, the listening effect is significantly improved. Based on this, in order to further improve the listening effect of the user, the overlapping ratio between the area of ​​the first projection and the area of ​​the projection of the user's concha on the sagittal plane is 44.01% or more. Preferably, the overlap ratio between the area of ​​the first projection and the area of ​​the projection of the user's concha onto the sagittal plane is 57.89% or more. Note that in the examples of the present specification, the frequency response curve corresponding to the overlap ratio between the measured area of ​​the first projection and the area of ​​the projection of the user's concha onto the sagittal plane is measured by changing the mounting position of the sound generating unit (for example, by translating it along the sagittal axis or vertical axis) when the mounting angle of the sound generating unit (the included angle between the upper wall or lower wall and the horizontal direction) and the dimensions of the sound generating unit are constant.

[0030] In the open-type earphone according to the embodiment of the present specification, at least a portion of the sound generating unit 11 is inserted into the cavity of the concha, and the overlap ratio between the area of ​​the first projection onto the sagittal plane and the area of ​​the projection of the user's cavity of the concha onto the sagittal plane is controlled to be 44.01% or more, thereby enabling the sound generating unit 11 and the user's cavity of the concha to closely engage with each other and form the acoustic model shown in FIG. 4, thereby increasing the listening volume at the listening position of the open-type earphone (e.g., the ear canal opening), particularly the listening volume for mid-low frequencies.

[0031] In addition, in order to ensure that the user's ear canal is not blocked when wearing the open-type earphone 10, and to maintain the ear canal open so that the user can obtain the sound output from the open-type earphone 10 and obtain sound from the external environment, the overlapping ratio between the area of ​​the first projection of the sound generating unit 11 onto the sagittal plane and the area of ​​the projection of the concha cavity onto the sagittal plane should not be too large. If the overlapping ratio between the area of ​​the first projection of the sound generating unit 11 onto the sagittal plane and the area of ​​the projection of the user's concha cavity onto the sagittal plane is too small in the wearing state, the dimension of the sound generating unit 11 entering the concha cavity is too small, so the fit area between the sound generating unit 11 and the user's concha cavity is small, and the concha cavity cannot be used to play a role of sufficient support and position restriction for the sound generating unit 11, resulting in a problem that the wearing is unstable and easy to come off, while the dimension of the gap formed by the sound generating unit 11 and the concha cavity is too large, which affects the listening volume at the user's ear canal. On the premise that the open-type earphones do not block the user's ear canal, in order to ensure stability, comfort and excellent listening effect when the user wears the open-type earphones, in some embodiments, the overlapping ratio between the area of ​​the first projection of the sound generating unit 11 onto the sagittal plane and the area of ​​the projection of the user's concha cavity onto the sagittal plane may be 44.01% to 77.88%, so that when a part or the entire structure of the sound generating unit 11 is inserted into the concha cavity, the acting force of the concha cavity on the sound generating unit 11 plays a role of providing a certain support and positional restriction to the sound generating unit 11, and further improving the stability and comfort when worn. In addition, the sound generating unit 11 may form an acoustic model shown in FIG. 4 with the concha cavity, which ensures the listening volume at the user's listening position (for example, the concha opening) and reduces the sound leakage volume in the far field. Preferably, the overlapping ratio between the area of ​​the first projection of the sound generating unit 11 onto the sagittal plane and the area of ​​the projection of the cavity of the concha of the user onto the sagittal plane may be 46% to 71.94%. More preferably, the overlapping ratio between the area of ​​the first projection of the sound generating unit 11 onto the sagittal plane and the area of ​​the projection of the cavity of the concha of the user onto the sagittal plane may be 48% to 65%.More preferably, the overlapping ratio between the area of ​​the first projection of the sound generating unit 11 onto the sagittal plane and the area of ​​the projection of the user's cavity of the concha onto the sagittal plane may be 57.89% to 62%.

[0032] There may be differences in the size and contour shape of the concha cavity of different users (e.g., different ages, different sexes, different heights and weights), and the area of ​​the projection of the concha cavity of different users onto the sagittal plane may be within a certain range (e.g., 320 mm 2 ~410mm 2 ). In combination with the above, the overlapping ratio between the area of ​​the projection of the sound generating unit 11 onto the sagittal plane and the area of ​​the projection of the cavity of the concha onto the sagittal plane should not be too large or too small, and accordingly, the overall dimensions of the sound generating unit 11 (particularly the dimensions of the sound generating unit 11 along the long axis direction and the dimensions of the sound generating unit 11 along the short axis direction) should not be too large or too small. For example, if the area of ​​the projection of the sound generating unit 11 onto the sagittal plane is too small, the sound generating unit 11 cannot sufficiently cover the cavity of the concha, and the dimensions of the gap formed between the sound generating unit 11 and the cavity of the concha are large, so the listening volume at the user's ear canal opening is low. If the area of ​​the projection of the sound generating unit 11 onto the sagittal plane is too large, the sound generating unit 11 may cover the user's ear canal opening, so the ear canal opening cannot be kept open, which affects the user's acquisition of sound from the external environment. In order to ensure the listening effect when the user wears the open-type earphone and to keep the ear canal open to obtain sound from the external environment, in some embodiments, the area of ​​the first projection of the sound generating unit 11 on the sagittal plane is 202 mm 2 ~560mm 2 Preferably, the area of ​​the first projection of the sound generating unit 11 onto the sagittal plane is 220 mm 2 ~500mm 2 More preferably, the area of ​​the first projection of the sound generating unit 11 onto the sagittal plane is 300 mm 2 ~470mm 2 More preferably, the area of ​​the first projection of the sound generating unit 11 onto the sagittal plane is 330 mm 2 ~440mm 2 may be also possible.

[0033] As shown in FIG. 5, the shape of the first projection of the sound generating unit 11 on the sagittal plane may include a shape in the long axis direction Y and a shape in the short axis direction Z. In some embodiments, if the dimensions of the sound generating unit 11 in the long axis direction Y or the short axis direction Z are too small, the volume of the sound generating unit 11 is relatively small, and the area of ​​the diaphragm installed inside the sound generating unit 11 is also relatively small, which causes the efficiency of the diaphragm pushing the air inside the housing of the sound generating unit 11 to generate sound to be low, which affects the acoustic output effect of the open-type earphone. In addition, if the dimensions of the sound generating unit 11 in the long axis direction Y are too large, the sound generating unit 11 cannot enter the concha cavity beyond the range of the concha cavity and cannot form a similar cavity structure, or the dimensions of the gap formed between the sound generating unit 11 and the concha cavity are large, which affects the listening volume at the ear canal opening and the sound leakage reduction effect in the far field when the user wears the open-type earphone 10. On the other hand, if the dimension of the sound generating unit 11 in the short axis direction Z is too large, the sound generating unit 11 may cover the user's ear canal, which affects the user's acquisition of sound information from the external environment. In some embodiments, in order to ensure that the user has excellent sound output quality when wearing the open-type earphone 10, the range of the dimension of the shape of the first projection along the long axis direction Y may be 12 mm to 32 mm. Preferably, the range of the dimension of the shape of the first projection along the long axis direction Y may be 18 mm to 29 mm. More preferably, the range of the dimension of the shape of the first projection along the long axis direction Y may be 20 mm to 27 mm, and more preferably, the range of the dimension of the shape of the first projection along the long axis direction Y may be 22 mm to 25 mm. Accordingly, the range of the dimension of the shape of the first projection along the short axis direction Z may be 4.5 mm to 18 mm. Preferably, the range of the dimension of the shape of the first projection along the short axis direction Z may be 10 mm to 15 mm. More preferably, the range of the dimension of the shape of the first projection along the short axis direction Z may be 11 mm to 13.5 mm. More preferably, the size of the shape of the first projection along the minor axis direction Z may be in the range of 12 mm to 13 mm.In order to further explain the effect of the shape of the first projection of the sound generating unit 11 onto the sagittal plane on the listening effect when the user is wearing the open-type earphones, the ratio between the dimensions of the shape of the first projection of the sound generating unit 11 onto the sagittal plane along the major axis direction Y and the dimensions of the shape of the first projection of the sound generating unit 11 onto the sagittal plane along the minor axis direction Z will be described below as an example.

[0034] FIG. 9 shows a case where the area of ​​the first projection of the voice generating unit 11 onto the sagittal plane is constant (for example, 119 mm 29 shows schematic diagrams of exemplary frequency response curves corresponding to different ratios between the dimension of the first projection of the sound generating unit 11 on the sagittal plane along the long axis direction Y and the dimension of the first projection of the sound generating unit 11 on the sagittal plane along the short axis direction Z when the sound generating unit 11 is in the long axis direction Y. In FIG. 9, the horizontal axis indicates frequency (unit: Hz), and the vertical axis indicates total sound pressure levels (unit: dB) corresponding to different ratios between the dimension of the first projection of the sound generating unit 11 on the sagittal plane along the long axis direction Y and the dimension of the first projection of the sound generating unit 11 on the sagittal plane along the short axis direction Z. In order to easily distinguish different frequency response curves, the frequency response curves shown in FIG. 9 correspond to L5, L4, L3, L2, and L1, respectively, from top to bottom, within the range of 100 Hz to 1000 Hz. L1 is a frequency response curve corresponding to the case where the ratio of the dimension of the first projection along the major axis Y to the dimension of the first projection along the minor axis Z is 4.99 (i.e., the dimension of the first projection along the major axis Y is 24.93 mm and the dimension of the first projection along the minor axis Z is 4.99 mm), L2 is a frequency response curve corresponding to the case where the ratio of the dimension of the first projection along the major axis Y to the dimension of the first projection along the minor axis Z is 3.99 (i.e., the dimension of the first projection along the major axis Y is 22.43 mm and the dimension of the first projection along the minor axis Z is 5.61 mm), and L3 is a frequency response curve corresponding to the case where the ratio of the dimension of the first projection along the major axis Y to the dimension of the first projection along the minor axis Z is 3.04 (i.e., the dimension of the first projection along the major axis Y is 22.43 mm and the dimension of the first projection along the minor axis Z is 5.61 mm). L1 is a frequency response curve corresponding to a case where the dimension of the first projection along the major axis direction Y is 19.61 mm and the dimension of the first projection along the minor axis direction Z is 6.54 mm), L2 is a frequency response curve corresponding to a case where the ratio of the dimension of the first projection along the major axis direction Y to the dimension of the first projection along the minor axis direction Z is approximately 2.0 (i.e., the dimension of the first projection along the major axis direction Y is 16.33 mm and the dimension of the first projection along the minor axis direction Z is 8.16 mm), and L5 is a frequency response curve corresponding to a case where the ratio of the dimension of the first projection along the major axis direction Y to the dimension of the first projection along the minor axis direction Z is 1.0 (i.e., the dimension of the first projection along the major axis direction Y is 12.31 mm and the dimension of the first projection along the minor axis direction Z is 12.31 mm).As can be seen from Fig. 9, the resonance frequencies corresponding to the frequency response curves L1 to L5 are almost the same (all about 3500Hz), but when the ratio between the dimension of the first projection along the long axis direction Y and the dimension of the first projection along the short axis direction Z is 1.0 to 3.0, the frequency response curve of the sound generating unit 11 is smooth overall and has a better frequency response at 100Hz to 3500Hz, and when the frequency is 5000Hz, the larger the ratio between the dimension of the first projection along the long axis direction Y and the dimension of the first projection along the short axis direction Z, the faster the frequency response of the sound at the ear canal of the sound generating unit 11 drops. Based on this, in some embodiments, in order to allow the user to experience an excellent sound output effect when wearing the open-type earphone, the ratio between the dimension of the first projection of the sound generating unit 11 on the sagittal plane along the long axis direction Y and the dimension of the projection of the sound generating unit 11 on the sagittal plane along the short axis direction Z can be 1.0 to 3.0. In some embodiments, when the area of ​​the first projection is constant, the smaller the ratio between the dimension of the first projection of the sound generating unit 11 onto the sagittal plane along the long axis direction Y and the dimension of the projection of the sound generating unit 11 onto the sagittal plane along the short axis direction Z, the larger the dimension of the projection of the sound generating unit 11 onto the sagittal plane along the short axis direction Z. If the dimension of the projection of the sound generating unit 11 onto the sagittal plane along the short axis direction Z is too large, the sound generating unit 11 will not be able to enter the user's concha cavity well, which may further cause problems with stability and comfort when worn. Therefore, in order to ensure both stability and comfort when worn, the ratio between the dimension of the first projection of the sound generating unit 11 onto the sagittal plane along the long axis direction Y and the dimension of the projection of the sound generating unit 11 onto the sagittal plane along the short axis direction Z can be set to 1.4 to 2.5. Preferably, the ratio of the dimension of the first projection of the sound generating unit 11 onto the sagittal plane along the major axis direction Y to the dimension of the projection of the sound generating unit 11 onto the sagittal plane along the minor axis direction Z may be 1.4 to 2.3. More preferably, the ratio of the dimension of the first projection of the sound generating unit 11 onto the sagittal plane along the major axis direction Y to the dimension of the projection of the sound generating unit 11 onto the sagittal plane along the minor axis direction Z may be 1.45 to 2.0. As can be seen, when the sound generating unit 11 has a different aspect ratio, the first projection of the sound generating unit 11 onto the sagittal plane and the projection of the cavity of the concha onto the sagittal plane will have different overlap percentages.In some embodiments, by controlling the ratio between the dimension of the first projection of the sound generating unit 11 onto the sagittal plane along the major axis direction Y and the dimension of the projection of the sound generating unit 11 onto the sagittal plane along the minor axis direction Z to 1.4 to 3, in a normal wearing state, the area of ​​the projection of the sound generating unit 11 onto the sagittal plane is relatively appropriate, and it is possible to avoid a situation in which the area of ​​the projection of the sound generating unit 11 onto the sagittal plane is too small to cause a large dimension of the gap formed between the sound generating unit 11 and the concha cavity, resulting in a low listening volume at the user's ear canal opening, and also to avoid a situation in which the area of ​​the projection of the sound generating unit 11 onto the sagittal plane is too large to maintain an open state of the ear canal opening, thereby affecting the user's acquisition of sound from the external environment, thereby allowing the user to have a good acoustic experience.

[0035] The measured frequency response curve in Fig. 9 was obtained by a simulation experiment, in which the human hearing system was simulated by a P.574.3 type wideband ear simulator model, and the human pinna was simulated by the pinna defined in the ITU-TP.57 standard, which includes the geometric shape of the ear canal. In the examples of this specification, the frequency response curves corresponding to the different measured dimensions in the major axis direction and the dimensions in the minor axis direction were measured by changing the dimensions in the different major axis direction and the minor axis direction when the mounting angle (the included angle between the upper wall or the lower wall and the horizontal direction) and the mounting position of the sound generating unit were constant.

[0036] In some embodiments, the dimension of the sound-generating unit 11 in the thickness direction X also affects the listening effect when a user is wearing the open-type earphone, as will be further explained below with reference to FIG. 10.

[0037] 10 shows frequency response curves when the size of the sound generating unit 11 in the thickness direction X is different, when the area of ​​the first projection of the sound generating unit 11 on the sagittal plane is constant, and the ratio between the size of the first projection along the major axis direction Y and the size of the projection of the sound generating unit 11 on the sagittal plane along the minor axis direction Z is constant. In FIG. 10, the horizontal axis indicates frequency (unit: Hz), and the vertical axis indicates sound pressure level (unit: dB) at the ear canal opening at different frequencies. Frequency response curve 1001 is a frequency response curve corresponding to the case where the size of the sound generating unit 11 in the thickness direction X is 20 mm, frequency response curve 1002 is a frequency response curve corresponding to the case where the size of the sound generating unit 11 in the thickness direction X is 10 mm, frequency response curve 1003 is a frequency response curve corresponding to the case where the size of the sound generating unit 11 in the thickness direction X is 5 mm, and frequency response curve 1004 is a frequency response curve corresponding to the case where the size of the sound generating unit 11 in the thickness direction X is 1 mm. The dimension of the sound generating unit 11 along the thickness direction X (also referred to as thickness) is directly proportional to the dimension of the front cavity of the sound generating unit 11 along the thickness direction X, and the smaller the dimension of the front cavity along the thickness direction X, the larger the resonance frequency corresponding to the corresponding resonance peak of the front cavity, and the flatter the frequency response curve in the low frequency range (100Hz to 1000Hz). In some embodiments, the sound output hole is acoustically coupled to the front cavity, and the sound in the front cavity is transmitted to the user's ear canal through the sound output hole and received by the user's hearing system. If the dimension of the sound generating unit 11 along the thickness direction X is too large, the resonance frequency corresponding to the corresponding resonance peak of the front cavity of the sound generating unit 11 is too small, which affects the acoustic performance of the sound generating unit 11 in the low frequency range. In addition, when in a worn state, the overall dimension or weight of the sound generating unit 11 is large, which affects the stability and comfort when worn. If the dimension of the sound generating unit 11 in the thickness direction X is too small, the space of the front and rear cavities of the sound generating unit 11 will be limited, which will affect the amplitude of the diaphragm and limit the output of the sound generating unit 11 at low frequencies and large amplitudes.Based on this, in order to ensure that the sound generating unit 11 has an excellent acoustic output effect and to ensure stability when worn, in some embodiments, the thickness of the sound generating unit 11 (the dimension of the sound generating unit 11 along the thickness direction) may be 2 mm to 20 mm. Preferably, the thickness of the sound generating unit 11 may be 5 mm to 15 mm. More preferably, the thickness of the sound generating unit 11 may be 8 mm to 12 mm. Note that, when the sound generating unit 11 is worn, if at least one of the two side walls (i.e., the inner surface facing the outside of the user's ear and the outer surface facing away from the outside of the user's ear) that are installed opposite to each other in the thickness direction X is not flat, the thickness of the sound generating unit 11 may refer to the maximum distance between the inner surface and the outer surface of the sound generating unit 11 in the thickness direction X.

[0038] In the examples of this specification, the measured frequency response curves corresponding to different thicknesses were measured by changing the dimension of the sound generating unit in the thickness direction when the mounting angle (the angle between the upper or lower wall and the horizontal direction) and mounting position of the sound generating unit were constant, and the dimension in the major axis direction and the dimension in the minor axis direction were constant.

[0039] 11A-11C are schematic diagrams of different exemplary engagement positions of an open earphone according to the present disclosure with a user's ear canal.

[0040] The dimensions of the gap formed between the sound generating unit 11 and the edge of the cavity of the concha are related to the inclination angle between the projection of the upper wall 111 (also called the upper surface) or the lower wall 112 (also called the lower surface) of the sound generating unit 11 onto the sagittal plane and the horizontal direction (parallel to and in the same direction as the sagittal axis S), the dimensions of the sound generating unit 11 (e.g., the dimension along the short axis direction Z and the dimension along the long axis direction Y shown in Figure 11A, and the dimension in the thickness direction X shown in Figure 3), as well as the distance between the end FE of the sound generating unit 11 and the edge of the cavity of the concha, and the distance between the end FE of the sound generating unit 11 and the edge of the cavity of the concha can be expressed by the distance between the midpoint of the projection of the end FE of the sound generating unit 11 onto the sagittal plane and the projection of the edge of the cavity of the concha onto the sagittal plane. The cavity of the concha refers to the concave region below the crus helix, i.e. the edge of the cavity of the concha is composed of at least the lower sidewall of the crus helix, the contour of the tragus, the intertragic notch, the antitragic apex, the antihelical notch, and the contour of the antihelical body that corresponds to the cavity of the concha. The projection of the edge of the cavity of the concha onto the sagittal plane is the contour of the projection of the cavity of the concha onto the sagittal plane. Specifically, one end of the sound generating unit 11 is connected to the hanging structure 12 (the second ear hook portion 122), and when worn by a user, a part or the entire structure of the sound generating unit 11 enters the cavity of the concha, and the position of the end FE (free end) of the sound generating unit 11 relative to the edge of the cavity of the concha affects the overlap ratio between the area of ​​the first projection of the sound generating unit 11 onto the sagittal plane and the area of ​​the projection of the cavity of the concha onto the sagittal plane, thereby affecting the size of the gap formed between the sound generating unit 11 and the cavity of the concha, and further affecting the listening volume at the opening of the user's ear canal. Furthermore, the distance between the midpoint of the projection of the end FE of the sound generating unit 11 onto the sagittal plane and the projection of the edge of the cavity of the concha onto the sagittal plane can reflect the position of the end FE of the sound generating unit 11 relative to the cavity of the concha and the degree to which the sound generating unit 11 covers the cavity of the concha of the user. When the projection of the end FE of the sound generating unit 11 onto the sagittal plane is a curve or a broken line, the midpoint of the projection of the end FE of the sound generating unit 11 onto the sagittal plane can be selected by the following exemplary method: Two points on the projection of the end FE onto the sagittal plane that are the greatest distance apart along the short axis direction are selected to draw a line segment, the midpoint of the line segment is selected to draw a perpendicular bisector, and the point where the perpendicular bisector and the projection intersect becomes the midpoint of the projection of the end of the sound generating unit 11 onto the sagittal plane.In some embodiments, when the end FE of the sound generating unit 11 is a curved surface, a tangent point of the projection that is parallel to the minor axis direction Z may be selected as the midpoint of the projection of the end FE of the sound generating unit 11 onto the sagittal plane.

[0041] As shown in Fig. 11A, when the sound generating unit 11 is not in contact with the edge of the cavity of the concha 102, the end FE of the sound generating unit 11 is located inside the cavity of the concha 102, that is, the midpoint of the projection of the end FE of the sound generating unit 11 onto the sagittal plane does not overlap with the projection of the edge of the cavity of the concha 102 onto the sagittal plane. As shown in Fig. 11B, the sound generating unit 11 of the open-type earphone 10 enters the cavity of the concha 102, and the end FE of the sound generating unit 11 abuts on the edge of the cavity of the concha 102, that is, the midpoint of the projection of the end FE of the sound generating unit 11 onto the sagittal plane overlaps with the projection of the edge of the cavity of the concha 102 onto the sagittal plane. As shown in Fig. 11C, the sound generating unit 11 of the open-type earphone 10 covers the cavity of the concha, and the end FE of the sound generating unit 11 is located between the edge of the cavity of the concha 102 and the inner contour 1014 of the auricle.

[0042] As shown in Figures 11A to 11C, when the end FE of the sound generating unit 11 is located within the edge of the cavity of the concha 102, if the distance between the midpoint C3 of the projection of the end FE of the sound generating unit 11 onto the sagittal plane and the projection of the edge of the cavity of the concha 102 onto the sagittal plane is too large, the overlapping ratio between the area of ​​the first projection of the sound generating unit 11 onto the sagittal plane and the area of ​​the projection of the cavity of the concha onto the sagittal plane becomes too small, and the dimension of the gap formed between the sound generating unit 11 and the edge of the cavity of the concha 102 becomes large, affecting the listening volume at the user's ear canal opening. When the midpoint C3 of the projection of the end FE of the sound generating unit onto the sagittal plane is located between the projection of the edge of the cavity of the concha 102 onto the sagittal plane and the projection of the inner contour 1014 of the auricle onto the sagittal plane, if the distance between the midpoint C3 of the projection of the end FE of the sound generating unit onto the sagittal plane and the projection of the edge of the cavity of the concha 102 onto the sagittal plane is too large, the end FE of the sound generating unit 11 interferes with the auricle, and the proportion of the sound generating unit 11 covering the cavity of the concha 102 cannot be increased. In addition, when the end FE of the sound generating unit 11 is not located within the cavity of the concha 102 while the sound generating unit 11 is worn by a user, the edge of the cavity of the concha 102 cannot serve as a positional restriction for the sound generating unit 11, and the sound generating unit 11 is likely to come off. In addition, when the dimensions of the sound generating unit 11 increase, its own weight increases, affecting the comfort of the user when wearing the sound generating unit 11 and the convenience of carrying the sound generating unit 11. In addition, when the projection of the end FE of the sound generating unit 11 onto the sagittal plane is a curve or a broken line, the midpoint of the projection of the end FE of the sound generating unit 11 onto the sagittal plane can be selected by the following exemplary method. A line segment is drawn by selecting the start point and end point of the projection of the end FE onto the sagittal plane, and a perpendicular bisector is drawn by selecting the midpoint of the line segment, and the point where the perpendicular bisector intersects with the projection becomes the midpoint of the projection of the end of the sound generating unit 11 onto the sagittal plane. In some embodiments, when the end FE of the sound generating unit 11 is a curved surface, a tangent line of the projection parallel to the minor axis direction Z may be selected to be the midpoint of the projection of the end FE of the sound generating unit 11 onto the sagittal plane.

[0043] 12 is a schematic diagram of exemplary frequency response curves corresponding to different distances between the projection of the end of the sound generating unit on the sagittal plane and the projection of the edge of the concha cavity on the sagittal plane according to some embodiments of the present specification. As shown in FIG. 12, the horizontal axis indicates frequency (unit: Hz), and the vertical axis indicates sound pressure level (unit: dB) at the ear canal opening at different frequencies. Frequency response curve 1201 is a frequency response curve when the distance between the midpoint C3 of the projection of the end of the sound generating unit on the sagittal plane and the projection of the edge of the concha cavity on the sagittal plane is 0 mm (for example, in the worn state, the end of the sound generating unit 11 abuts on the edge of the concha cavity), frequency response curve 1202 is a frequency response curve when the distance between the midpoint C3 of the projection of the end of the sound generating unit on the sagittal plane and the projection of the edge of the concha cavity on the sagittal plane is 4.77 mm, and frequency response curve 1203 is a frequency response curve when the distance between the midpoint C3 of the projection of the end of the sound generating unit on the sagittal plane and the projection of the edge of the concha cavity on the sagittal plane is 4.77 mm. frequency response curve 1203 is a frequency response curve when the distance between the midpoint C3 of the projection of the end of the sound generating unit onto the sagittal plane and the projection of the edge of the concha cavity onto the sagittal plane is 7.25 mm, frequency response curve 1204 is a frequency response curve when the distance between the midpoint C3 of the projection of the end of the sound generating unit onto the sagittal plane and the projection of the edge of the concha cavity onto the sagittal plane is 10.48 mm, frequency response curve 1205 is a frequency response curve when the distance between the midpoint C3 of the projection of the end of the sound generating unit onto the sagittal plane and the projection of the edge of the concha cavity onto the sagittal plane is 15.3 mm, and frequency response curve 1206 is a frequency response curve when the distance between the midpoint C3 of the projection of the end of the sound generating unit onto the sagittal plane and the projection of the edge of the concha cavity onto the sagittal plane is 19.24 mm. 12, when the distance between the midpoint C3 of the projection of the end of the sound generating unit 11 onto the sagittal plane and the projection of the edge of the cavity of the concha onto the sagittal plane is 0 mm (for example, when worn, the end of the sound generating unit 11 abuts the edge of the cavity of the concha), 4.77 mm, or 7.25 mm, the sound pressure level of the sound measured at the ear canal opening is large. When the distance between the midpoint C3 of the projection of the end of the sound generating unit onto the sagittal plane and the projection of the edge of the cavity of the concha onto the sagittal plane is 19.24 mm, the sound pressure level of the sound measured at the ear canal opening is relatively small.In other words, in the worn state, the greater the distance between the midpoint C3 of the projection of the end of the sound generating unit 11 onto the sagittal plane and the projection of the edge of the cavity of the concha onto the sagittal plane, i.e., the less the structure of the sound generating unit 11 that has entered the cavity of the concha, the smaller the overlapping ratio between the area of ​​the first projection of the sound generating unit 11 onto the sagittal plane and the area of ​​the projection of the edge of the cavity of the concha onto the sagittal plane, and the lower the listening effect at the ear canal opening. Based on this, in order to ensure that the open-type earphone 10 has an excellent listening effect and to ensure comfort and stability when worn by the user, in some embodiments, the distance between the midpoint C3 of the projection of the end FE of the sound generating unit 11 onto the sagittal plane and the projection of the edge of the cavity of the concha onto the sagittal plane is set to 16 mm or less. Preferably, the distance between the midpoint C3 of the projection of the end FE of the sound generating unit 11 onto the sagittal plane and the projection of the edge of the cavity of the concha onto the sagittal plane is set to 13 mm or less. More preferably, the distance between the midpoint C3 of the projection of the end FE of the sound generating unit 11 onto the sagittal plane and the projection of the edge of the cavity of the concha onto the sagittal plane may be 0 mm to 10.92 mm. Merely by way of example, in some embodiments, the distance between the midpoint C3 of the projection of the end FE of the sound generating unit 11 onto the sagittal plane and the projection of the edge of the cavity of the concha onto the sagittal plane may be 0 mm to 15.3 mm. Preferably, the distance between the midpoint C3 of the projection of the end FE of the sound generating unit 11 onto the sagittal plane and the projection of the edge of the cavity of the concha onto the sagittal plane may be 0 mm to 10.48 mm. More preferably, the distance between the midpoint C3 of the projection of the end FE of the sound generating unit 11 onto the sagittal plane and the projection of the edge of the cavity of the concha onto the sagittal plane may be 0 mm to 7.25 mm. More preferably, the distance between the midpoint C3 of the projection of the end FE of the sound generating unit 11 onto the sagittal plane and the projection of the edge of the cavity of the concha onto the sagittal plane may be 0 mm to 4.77 mm.In some embodiments, the end of the sound generating unit may abut the edge of the cavity of the concha, where it can be understood that the projection of the end FE of the sound generating unit 11 onto the sagittal plane overlaps with the projection of the edge of the cavity of the concha onto the sagittal plane (for example, the position of the sound generating unit 11 relative to the cavity of the concha shown in FIG. 11A), that is, when the distance between the projection of the end of the sound generating unit onto the sagittal plane and the projection of the edge of the cavity of the concha onto the sagittal plane is 0 mm, the sound generating unit 11 can have a good frequency response, and at this time, the end of the sound generating unit 11 abuts the edge of the cavity of the concha, playing the role of supporting and limiting the position of the sound generating unit 11, thereby improving the stability when the user is wearing the open-type earphone. In some embodiments, the distance between the midpoint C3 of the projection of the end FE of the sound generating unit 11 onto the sagittal plane and the projection of the edge of the cavity of the concha 102 onto the sagittal plane may refer to the minimum distance from the midpoint C3 of the projection of the end FE of the sound generating unit 11 onto the sagittal plane to the projection of the edge of the cavity of the concha 102 onto the sagittal plane. In some embodiments, the distance between the midpoint C3 of the projection of the end FE of the sound generating unit 11 onto the sagittal plane and the projection of the edge of the cavity of the concha 102 onto the sagittal plane may refer to the distance along the sagittal axis. In addition, the distance between the projection of the end of the sound generating unit 11 onto the sagittal plane and the projection of the edge of the cavity of the concha in FIG. 12 onto the sagittal plane is measured in a scenario in which the end of the sound generating unit 11 enters the cavity of the concha. In a specific wearing scenario, a point other than the midpoint C3 of the projection of the end FE of the sound generating unit 11 onto the sagittal plane may abut the edge of the cavity of the concha, and in this case, the distance between the midpoint C3 of the projection of the end FE of the sound generating unit 11 onto the sagittal plane and the projection of the edge of the cavity of the concha onto the sagittal plane may be greater than 0 mm. In some embodiments, the distance between the midpoint C3 of the projection of the end FE of the sound generating unit 11 onto the sagittal plane and the projection of the edge of the cavity of the concha onto the sagittal plane may be 2 mm to 16 mm. Preferably, the distance between the midpoint C3 of the projection of the end FE of the sound generating unit 11 onto the sagittal plane and the projection of the edge of the cavity of the concha onto the sagittal plane may be 4 mm to 10.48 mm.Furthermore, since the cavity of the concha 102 has a recessed structure, the side wall corresponding to the cavity of the concha 102 is not a flat wall surface, the projection of the edge of the cavity of the concha onto the sagittal plane has an irregular two-dimensional shape, and the projection of the side wall corresponding to the cavity of the concha 102 onto the sagittal plane may be on the contour of the shape or may be outside the contour of the shape, the midpoint of the projection of the end FE of the sound generating unit 11 onto the sagittal plane does not have to overlap with the projection of the edge of the cavity of the concha 102 onto the sagittal plane. For example, the midpoint of the projection of the end FE of the sound generating unit 11 onto the sagittal plane may be inside or outside the projection of the edge of the cavity of the concha 102 onto the sagittal plane. In the embodiments of the present specification, when the end FE of the sound generating unit 11 is located in the cavity of the concha 102, if the distance between the midpoint of the projection of the end FE of the sound generating unit 11 onto the sagittal plane and the projection of the edge of the cavity of the concha 102 onto the sagittal plane is within a certain range (e.g., 6 mm or less), the end FE of the sound generating unit 11 can be considered to abut the edge of the cavity of the concha 102.

[0044] In the examples of this specification, the frequency response curves corresponding to different distances from the midpoint of the projection of the measured end FE of the sound generating unit onto the sagittal plane to the projection of the edge of the concha cavity onto the sagittal plane were measured by changing the mounting position of the sound generating unit (e.g., by translating it parallel along the sagittal axis direction) when the mounting angle of the sound generating unit (the included angle between the upper or lower wall and the horizontal direction), the dimension in the major axis direction, the dimension in the minor axis direction, and the dimension in the thickness direction are constant.

[0045] 11A to 11C, when the open-type earphone 10 is in a worn state, the first projection of the sound generating unit 11 onto the sagittal plane may at least partially overlap with the projection of the ear canal opening onto the sagittal plane (e.g., the dotted area 1016 shown in FIGS. 11A to 11C). The distance between the centroid O of the first projection of the sound generating unit 11 onto the sagittal plane and the centroid P of the projection of the ear canal opening onto the sagittal plane can reflect the relative positional relationship between the sound generating unit 11 and the ear canal opening, and the overlap ratio between the area of ​​the first projection of the sound generating unit 11 onto the sagittal plane and the area of ​​the projection of the ear canal opening onto the sagittal plane. The overlap ratio affects the number of leakage structures in the similar cavity structure formed by the sound generating unit 11 and the user's ear and the size of the opening of the leakage structure, and the size of the opening of the leakage structure directly affects the listening quality; specifically, the larger the opening of the leakage structure, the more sound components the sound generating unit 11 directly radiates to the outside, and the more difficult it becomes for the sound to reach the listening position.

[0046] FIG. 13A is a schematic diagram of exemplary frequency response curves corresponding to different overlap percentages between the area of ​​a first projection of a sound generating unit 11 onto the sagittal plane and the area of ​​a projection of the concha onto the sagittal plane in accordance with some embodiments of the present specification, and FIG. 13B is a schematic diagram of exemplary frequency response curves corresponding to different distances between the centroid of the first projection of a sound generating unit 11 onto the sagittal plane and the centroid of the projection of the auditory canal onto the sagittal plane in accordance with some embodiments of the present specification.

[0047] As shown in FIG. 13A, the horizontal axis represents the overlap ratio between the area of ​​the first projection of the sound generating unit 11 onto the sagittal plane and the area of ​​the projection of the cavity of the concha onto the sagittal plane, and the vertical axis represents the sound pressure level of the sound at the ear canal opening corresponding to different overlap ratios, and line 1301 represents a linear relationship fitted based on the overlap ratio between the area of ​​the first projection and the area of ​​the projection of the cavity of the concha onto the sagittal plane and the sound pressure level at the ear canal opening when the frequency is 500 Hz, line 1302 represents a linear relationship fitted based on the overlap ratio between the area of ​​the first projection and the area of ​​the projection of the cavity of the concha onto the sagittal plane and the sound pressure level at the ear canal opening when the frequency is 1 kHz, and line 1303 represents a linear relationship fitted based on the overlap ratio between the area of ​​the first projection and the area of ​​the projection of the cavity of the concha onto the sagittal plane and the sound pressure level at the ear canal opening when the frequency is 3 kHz. The white circles in FIG. 13A show test data corresponding to different overlap percentages between the area of ​​the first projection and the area of ​​the projection of the cavity of the concha onto the sagittal plane when the frequency is 500 Hz, the gray circles in FIG. 13A show test data corresponding to different overlap percentages between the area of ​​the first projection and the area of ​​the projection of the cavity of the concha onto the sagittal plane when the frequency is 1 kHz, and the black circles in FIG. 13A show test data corresponding to different overlap percentages between the area of ​​the first projection and the area of ​​the projection of the cavity of the concha onto the sagittal plane when the frequency is 3 kHz. As can be seen from FIG. 13A, when the frequency is different, the overlapping ratio between the area of ​​the first projection and the area of ​​the projection of the cavity of the concha on the sagittal plane shows an almost positive correlation with the magnitude of the sound pressure level at the opening of the ear canal of the user, and when the area of ​​the first projection of the sound generating unit 11 on the sagittal plane and the area of ​​the projection of the cavity of the concha on the sagittal plane have an overlapping portion, the sound of a specific frequency (for example, 500 Hz, 1 kHz, 3 kHz) measured at the opening of the ear canal is obviously increased compared to the case where the area of ​​the first projection of the sound generating unit 11 on the sagittal plane and the area of ​​the projection of the cavity of the concha on the sagittal plane do not have an overlapping ratio (overlapping ratio is 0). Based on this, in order to guarantee the sound output quality of the sound generating unit 11, the overlapping ratio between the first projection of the sound generating unit 11 on the sagittal plane and the projection of the cavity of the concha on the sagittal plane may be set to 44.01% to 80%.As shown in FIG. 13A, when the overlap ratio is 22% or 32%, the sound pressure level of the sound at the ear canal opening is high, but the structure of the sound generating unit 11 that penetrates into the concha cavity is limited, and the edge of the concha cavity cannot play a role in supporting and restricting the position of the end of the sound generating unit 11. When the overlap ratio is too large (for example, the overlap ratio is greater than 80%), the sound pressure level of the sound at the ear canal opening is high, but it affects the opening state of the ear canal opening. Preferably, in some embodiments, the overlap ratio between the first projection of the sound generating unit 11 onto the sagittal plane and the projection of the concha cavity onto the sagittal plane may be 45% to 71.49%.

[0048] As shown in FIG. 13B, the horizontal axis is the distance between the centroid O of the first projection of the sound generating unit 11 onto the sagittal plane and the centroid P of the projection of the auditory canal opening onto the sagittal plane, and the vertical axis is the sound pressure level of the sound at the auditory canal opening corresponding to different distances. Line 1304 shows a linear relationship fitted between the distance between the centroid O of the first projection of the sound generating unit 11 onto the sagittal plane and the centroid P of the projection of the ear canal opening onto the sagittal plane and the sound pressure level at the ear canal opening when the frequency is 500 Hz, line 1305 shows a linear relationship simulated between the distance between the centroid O of the first projection of the sound generating unit 11 onto the sagittal plane and the centroid P of the projection of the ear canal opening onto the sagittal plane and the sound pressure level at the ear canal opening when the frequency is 1 kHz, and line 1306 shows a linear relationship simulated between the distance between the centroid O of the first projection of the sound generating unit 11 onto the sagittal plane and the centroid P of the projection of the ear canal opening onto the sagittal plane and the sound pressure level at the ear canal opening when the frequency is 3 kHz. The white circles in Figure 13B show test data corresponding to different distances between the centroid O of the first projection of the sound generating unit 11 onto the sagittal plane and the centroid P of the projection of the ear canal opening onto the sagittal plane when the frequency is 500 Hz, the black circles in Figure 13B show test data corresponding to different distances between the centroid O of the first projection of the sound generating unit 11 onto the sagittal plane and the centroid P of the projection of the ear canal opening onto the sagittal plane when the frequency is 1 kHz, and the grey circles in Figure 13B show test data corresponding to different distances between the centroid O of the first projection of the sound generating unit 11 onto the sagittal plane and the centroid P of the projection of the ear canal opening onto the sagittal plane when the frequency is 3 kHz. As can be seen from Figure 13B, when the frequency is different, the distance between the centroid O of the first projection of the sound generating unit 11 onto the sagittal plane and the centroid P of the projection of the ear canal opening onto the sagittal plane shows an almost negative correlation with the magnitude of the sound pressure level at the user's ear canal opening, and overall, the sound pressure level of a sound of a specific frequency (e.g., 500 Hz, 1 kHz, 3 kHz) measured at the ear canal opening decreases as the distance between the centroid O of the first projection of the sound generating unit 11 onto the sagittal plane and the centroid P of the projection of the ear canal opening onto the sagittal plane increases, and as shown in Figures 13A and 13B, the greater the distance between the centroid O of the first projection of the sound generating unit 11 onto the sagittal plane and the centroid P of the projection of the ear canal opening onto the sagittal plane, the smaller the overlap ratio between the area of ​​the first projection of the sound generating unit 11 onto the sagittal plane and the area of ​​the projection of the ear canal opening onto the sagittal plane.The overlapping ratio affects the number of leakage structures of the similar cavity structure formed by the sound generating unit 11 and the user's ear and the size of the opening of the leakage structure, and the size of the opening of the leakage structure directly affects the listening quality, specifically, the larger the opening of the leakage structure, the more sound components the sound generating unit 11 directly radiates to the outside, and the more difficult it is for the sound to reach the listening position. Also, if the distance between the centroid O of the first projection of the sound generating unit 11 onto the sagittal plane and the centroid P of the projection of the ear canal opening onto the sagittal plane is too small, the overlapping ratio between the area of ​​the first projection of the sound generating unit 11 onto the sagittal plane and the area of ​​the projection of the ear canal opening onto the sagittal plane is too large, which may cause the sound generating unit 11 to cover the user's ear canal opening, affecting the user's acquisition of sound information from the external environment. As can be seen from Fig. 13B, taking the frequency as an example of 3kHz, when the distance between the centroid O of the first projection of the sound generating unit 11 onto the sagittal plane and the centroid P of the projection of the ear canal opening onto the sagittal plane is 7mm and 11mm, the measured sound pressure levels at the ear canal opening are -72dB and -70dB, respectively, and when the distance between the centroid O of the first projection of the sound generating unit 11 onto the sagittal plane and the centroid P of the projection of the ear canal opening onto the sagittal plane is 18mm and 22mm, the measured sound pressure levels at the ear canal opening are -80dB and -84.3dB, respectively. As can be seen from the above, the distance between the centroid O of the first projection of the sound generating unit 11 onto the sagittal plane and the centroid P of the projection of the ear canal opening onto the sagittal plane should not be too large. In some embodiments, in order to ensure the quality of the sound output of the sound generating unit 11 (e.g., the sound pressure level at the ear canal opening is greater than -80 dB) and to ensure that the user can receive sound information from the external environment, the distance between the centroid O of the first projection of the sound generating unit 11 onto the sagittal plane and the centroid P of the projection of the ear canal opening onto the sagittal plane may be 3 mm to 15 mm. Preferably, the distance between the centroid O of the first projection of the sound generating unit 11 onto the sagittal plane and the centroid P of the projection of the ear canal opening onto the sagittal plane may be 4 mm to 13 mm. More preferably, the distance between the centroid O of the first projection of the sound generating unit 11 onto the sagittal plane and the centroid P of the projection of the ear canal opening onto the sagittal plane may be 8 mm to 10 mm.

[0049] In the examples of this specification, the frequency response curves corresponding to different measured overlap ratios and the frequency response curves corresponding to different distances between the centroid of the first projection and the centroid of the projection of the auditory canal opening onto the sagittal plane were measured by changing the mounting position of the sound generating unit (e.g., by moving it parallel along the sagittal axis direction) when the mounting angle of the sound generating unit (the included angle between the upper or lower wall and the horizontal direction), the dimension in the major axis direction, the dimension in the minor axis direction, and the dimension in the thickness direction are constant.

[0050] The positional relationship between the sound generating unit 11 according to the embodiment of the present specification and the auricle, the cavity of the concha, or the ear canal opening can be determined by the following exemplary method. First, a photograph of a human head model having an ear is taken at a specific position along a direction directly facing the sagittal plane, and the edge of the cavity of the concha, the contour of the ear canal opening, and the contour of the auricle (e.g., inner contour and outer contour) are marked, and these marked contours can be regarded as the projection contour of each structure of the ear onto the sagittal plane. Then, at the specific position, a photograph of a human head model with an open-type earphone attached is taken from the same angle, and the contour of the sound generating unit is marked, and the contour can be regarded as the projection of the sound generating unit onto the sagittal plane, and the positional relationship between the sound generating unit (e.g., centroid, end, etc.) and the edge of the cavity of the concha, the ear canal opening, the inner contour, or the outer contour can be determined by comparative analysis.

[0051] The above-mentioned Figures 1 to 13B and the contents of the corresponding instructions relate to the case where the whole or part of the sound generating unit is inserted into the cavity of the concha when the open-type earphone is worn, but in some embodiments, the sound generating unit 11 does not need to be inserted into the cavity of the concha. For example, at least a part of the sound generating unit 11 shown in Figure 14 covers the antihelix region. Also, for example, the sound generating unit 11 shown in Figure 16E does not cover the antihelix region and is suspended relative to the cavity of the concha. Hereinafter, a specific description will be given with reference to Figures 14 to 18B.

[0052] FIG. 14 is an exemplary schematic view of an open-type earphone according to some other embodiments of the present disclosure.

[0053] As shown in Fig. 14, in some embodiments, when the open-type earphone 10 is in a worn state, at least a part of the sound generating unit 11 can cover the antihelix region of the user, and the antihelix region may include any one or more of the antihelix 105, the antihelix superior crus 1011, and the antihelix inferior crus 1012 shown in Fig. 1, and at this time, the sound generating unit 11 is located in the M1 region (shown in Fig. 1) above the concha 102 and the ear canal opening so that the ear canal opening of the user is in an open state. In some embodiments, the housing of the sound generating unit 11 may include at least one sound output hole and a decompression hole, the sound output hole is acoustically coupled to the front cavity of the open-type earphone 10, and the decompression hole is acoustically coupled to the rear cavity of the open-type earphone 10, and the sound output from the sound output hole and the sound output from the decompression hole can be regarded as approximately two point sound sources, and these two point sound sources have opposite sound phases and form a dipole. When a user wears an open-type earphone, the sound emission hole is located on a side wall of the sound generating unit 11 facing or close to the user's ear canal, and the decompression hole is located on a side wall of the sound generating unit 11 facing away from or away from the user's ear canal. Here, the housing of the sound generating unit 11 itself functions as a baffle, increasing the difference in acoustic distance between the sound emission hole and the decompression hole to the ear canal 101, thereby increasing the intensity of the sound in the ear canal 101. Furthermore, in the worn state, the side wall of the sound generating unit 11 abuts against the antihelix region, and the uneven structure of the antihelix region can also function as a baffle, and the uneven structure increases the acoustic distance over which the sound emitted from the decompression hole is transmitted to the ear canal 101, thereby increasing the difference in acoustic distance between the sound emission hole and the decompression hole to the ear canal 101, increasing the intensity of the sound in the ear canal 101, and reducing the volume of sound leakage in the far field.

[0054] FIG. 15 is a schematic diagram of an exemplary frequency response curve corresponding to different overlapping ratios between the first projection of the sound generating unit 11 onto the sagittal plane and the projection of the concha cavity onto the sagittal plane in a wearing manner in which at least a part of the sound generating unit 11 covers the antihelical region according to some embodiments of the present specification. In FIG. 15, the horizontal axis indicates frequency (unit: Hz), and the vertical axis indicates the measured sound pressure level (unit: dB) of different frequencies at the ear canal opening. As can be seen from FIG. 15, in a specific experiment, since the three-dimensional structure and overall dimensions of the sound generating unit 11 are constant, in order to ensure that the area of ​​the first projection of the sound generating unit 11 onto the sagittal plane is a constant value, here, experimental values ​​of different coverage ratios are obtained by translation along the direction of the sagittal axis and / or the vertical axis. The translation changes the position of the sound generating unit 11 relative to the antihelical region, and accordingly, the role of the baffle formed by the sound generating unit 11 and the antihelical region is weakened. In the worn state, the sound output hole is usually installed on a side wall close to or facing the ear canal opening of the sound generating unit 11, and in this case, the larger the overlap ratio between the area of ​​the first projection of the sound generating unit 11 on the sagittal plane and the area of ​​the projection of the cavity of the concha on the sagittal plane, the closer the sound output hole of the sound generating unit 11 is to the ear canal opening, so that even if the antihelical region and the role of the sound generating unit 11 as a baffle are weakened, the listening volume at the ear canal opening can be increased. As shown in Fig. 15, when the overlap ratio between the area of ​​the first projection of the sound generating unit 11 on the sagittal plane and the area of ​​the projection of the cavity of the concha on the sagittal plane is 11.82% or more, the listening volume at the ear canal opening is significantly increased compared to when the overlap ratio is less than 11.821%, that is, even if the sound generating unit 11 covers both a part of the cavity of the concha and the antihelical region, a better frequency response can be generated. Based on this, in some embodiments, in order to improve the listening effect when the user wears the open-type earphone, the sound generating unit 11 needs to cover the antihelix and satisfy the overlap ratio between the area of ​​the first projection onto the sagittal plane and the area of ​​the projection of the user's concha cavity onto the sagittal plane of 11.82% or more. Preferably, in some embodiments, the overlap ratio between the area of ​​the first projection onto the sagittal plane of the sound generating unit 11 and the area of ​​the projection of the user's concha cavity onto the sagittal plane may be 31.83% or more.Considering that if the overlap ratio between the area of ​​the first projection of the sound generating unit 11 on the sagittal plane and the area of ​​the projection of the cavity of the concha on the sagittal plane is too large, the sound generating unit 11 covers the ear canal opening, and the ear canal opening cannot be kept sufficiently open, which affects the user's acquisition of sound from the external environment, preferably, in some embodiments, the overlap ratio between the area of ​​the first projection of the sound generating unit 11 on the sagittal plane and the area of ​​the projection of the cavity of the concha of the user on the sagittal plane may be 11.82% to 62.50%. More preferably, in some embodiments, the overlap ratio between the area of ​​the first projection of the sound generating unit 11 on the sagittal plane and the area of ​​the projection of the cavity of the concha of the user on the sagittal plane may be 31.83% to 50.07%. More preferably, the overlap ratio between the area of ​​the first projection of the sound generating unit 11 onto the sagittal plane and the area of ​​the projection of the user's cavity of the concha onto the sagittal plane may be 35.55% to 45%. Note that in the examples of this specification, the frequency response curve corresponding to the overlap ratio between the measured area of ​​the first projection and the area of ​​the projection of the user's cavity of the concha onto the sagittal plane is measured by changing the mounting position of the sound generating unit (for example, by translating it along the sagittal axis or vertical axis) when the mounting angle of the sound generating unit (the included angle between the upper or lower wall and the horizontal direction, for example, the included angle between the upper wall and the horizontal direction is 0°) and the dimensions of the sound generating unit are constant.

[0055] In a wearing method in which at least a part of the sound generating unit 11 covers the antihelix of the user, the sound generating unit 11 does not enter the cavity of the concha of the user, and the included angle between the sound generating unit 11 and the sagittal plane is slightly smaller than in a wearing method in which at least a part of the sound generating unit 11 of the open-type earphone shown in FIG. 3 enters the cavity of the concha. Therefore, in a wearing method in which at least a part of the sound generating unit 11 covers the antihelix region of the user, the projection area of ​​the sound generating unit of the open-type earphone shown in FIG. 14 onto the sagittal plane is slightly larger than the projection area of ​​the sound generating unit of the open-type earphone shown in FIG. 14 onto the sagittal plane. For example, in some embodiments, the area of ​​the first projection of the sound generating unit 11 onto the sagittal plane in the worn state is 236 mm 2 ~565mm 2In some embodiments, in order to avoid a situation where the area of ​​the first projection of the sound generating unit 11 on the sagittal plane is too small, causing the sound generating unit to play a weak role as a baffle, and to avoid a situation where the area of ​​the first projection of the sound generating unit 11 on the sagittal plane is too large, causing the sound generating unit 11 to cover the ear canal and affect the user's acquisition of sound from the external environment, the area of ​​the first projection of the sound generating unit 11 on the sagittal plane in the worn state may be 250 mm 2 ~550mm 2 Preferably, in the worn state, the area of ​​the first projection of the sound generating unit 11 onto the sagittal plane is 270 mm 2 ~500mm 2 More preferably, in the worn state, the area of ​​the first projection of the sound generating unit 11 onto the sagittal plane is 290 mm 2 ~450mm 2 More preferably, in the worn state, the area of ​​the first projection of the sound generating unit 11 onto the sagittal plane is 320 mm 2 ~410mm 2 may be also possible.

[0056] As shown in FIG. 14, the projection shape of the first projection of the sound generating unit 11 onto the sagittal plane (for example, the dotted line region 1100 in FIG. 14) may include a long axis direction (for example, the Y axis direction) shape and a short axis direction (for example, the Z axis direction) shape. In some embodiments, if the dimension of the sound generating unit 11 in the long axis direction Y or the short axis direction Z is too small, the volume of the sound generating unit 11 is relatively small, and the area of ​​the diaphragm installed inside the sound generating unit 11 is also relatively small, which causes the efficiency of the diaphragm to push the air inside the housing of the sound generating unit 11 to generate sound at low frequencies to be low, affecting the acoustic output effect of the open-type earphone. Furthermore, if the dimension of the sound generating unit 11 in the long axis direction Y or the dimension in the short axis direction is too small, the distance between the sound output hole and the decompression hole of the sound generating unit 11 is too small, and the difference in acoustic distance between the sound at the sound output hole and the sound at the decompression hole is small, which affects the listening volume at the ear canal of the user. On the other hand, if the dimension of the sound generating unit 11 in the long axis direction Y is too large, the sound generating unit 11 may come out of the user's auricle, causing discomfort when worn. Also, if the dimension of the sound generating unit 11 in the long axis direction Y is too small, there is a gap between the end FE of the sound generating unit 11 and the inner contour 1014 of the auricle, and the sound emitted from the sound emission hole and the sound emitted from the decompression hole are acoustically short-circuited in the area between the end FE of the sound generating unit 11 and the inner contour 1014 of the auricle, so that the listening volume at the user's ear canal opening decreases, and the larger the area between the end FE of the sound generating unit 11 and the inner contour 1014 of the auricle, the more obvious the acoustic short-circuit phenomenon becomes. On the other hand, if the dimension of the sound generating unit 11 in the short axis direction Z is too large, the sound generating unit 11 may cover the user's ear canal opening, affecting the user's acquisition of sound information from the external environment. In some embodiments, in order to ensure that a user has good acoustic output quality and wearing comfort when wearing the open-type earphone 10, the range of dimensions of the shape of the first projection along the long axis direction Y may be 21 mm to 33 mm. Preferably, the range of dimensions of the shape of the first projection along the long axis direction Y may be 21.5 mm to 31 mm. More preferably, the range of dimensions of the shape of the first projection along the long axis direction Y may be 21.5 mm to 26.5 mm.Accordingly, in some embodiments, the range of dimensions of the shape of the first projection along the short axis direction Z is 11 mm to 18 mm. Preferably, the range of dimensions of the shape of the first projection along the short axis direction Z may be 11.5 mm to 16.5 mm. More preferably, the range of dimensions of the shape of the first projection along the short axis direction Z may be 11.5 mm to 16 mm. In order to further explain the influence of the shape of the first projection of the sound generating unit 11 onto the sagittal plane on the listening effect when the user is wearing the open-type earphone, the ratio between the dimension of the shape of the first projection of the sound generating unit 11 onto the sagittal plane along the long axis direction Y and the dimension of the shape of the first projection of the sound generating unit 11 onto the sagittal plane along the short axis direction Z will be exemplarily described below.

[0057] In the case where the wearing manner is constant (for example, the wearing position and the wearing angle are fixed), in the case where the sound generating unit 11 covers the antihelix, the influence on the acoustic output effect of the sound generating unit 11 due to the ratio between the dimension of the first projection of the sound generating unit 11 on the sagittal plane along the long axis direction Y and the dimension of the first projection of the sound generating unit 11 on the sagittal plane along the short axis direction Z can be considered to be substantially the same as that of the above-mentioned wearing manner where the sound generating unit 11 enters the cavity of the concha. When the ratio between the dimension of the first projection of the sound generating unit 11 on the sagittal plane along the long axis direction Y and the dimension of the first projection of the sound generating unit 11 on the sagittal plane along the short axis direction Z is 1.0 to 3.0, the frequency response curve of the sound generating unit 11 is smoother overall and has a better frequency response within the mid-low frequency range. When the frequency is in the high frequency range, the larger the ratio between the dimension of the first projection along the long axis direction Y and the dimension of the first projection along the short axis direction Z, the faster the frequency response of the sound at the ear canal of the sound generating unit 11 drops. Based on this, in some embodiments, in order to allow the user to experience a good sound output effect when wearing the open-type earphone, the ratio between the dimension of the first projection of the sound generating unit 11 on the sagittal plane along the long axis direction Y and the dimension of the projection of the sound generating unit 11 on the sagittal plane along the short axis direction Z can be 1.0 to 3.0. Similarly, in order to ensure both stability and comfort when worn, in some embodiments, the ratio between the dimension of the first projection of the sound generating unit 11 on the sagittal plane along the long axis direction Y and the dimension of the projection of the sound generating unit 11 on the sagittal plane along the short axis direction Z can be 1.4 to 2.5. Preferably, the ratio between the dimension of the first projection of the sound generating unit 11 onto the sagittal plane along the long axis direction Y and the dimension of the projection of the sound generating unit 11 onto the sagittal plane along the short axis direction Z may be 1.4 to 2.3. More preferably, the ratio between the dimension of the first projection of the sound generating unit 11 onto the sagittal plane along the long axis direction Y and the dimension of the projection of the sound generating unit 11 onto the sagittal plane along the short axis direction Z may be 1.45 to 2.0.

[0058] In the examples of this specification, the frequency response curves corresponding to different measured dimensions in the major axis direction and dimensions in the minor axis direction were measured by changing the dimensions in the major axis direction and dimensions in the minor axis direction when the mounting angle (the angle between the upper wall or lower wall and the horizontal direction) and mounting position of the sound generating unit were constant.

[0059] Similarly, when the wearing manner is constant (e.g., the wearing position and the wearing angle are fixed), for the wearing manner in which the sound generating unit 11 covers the antihelix, the influence of the thickness of the sound generating unit 11 on the sound output effect of the sound generating unit 11 can be considered to be approximately the same as the wearing manner in which the sound generating unit 11 enters the cavity of the concha described above. The dimension (also called thickness) of the sound generating unit 11 along the thickness direction X is directly proportional to the dimension of the front cavity of the sound generating unit 11 along the thickness direction X, and the smaller the dimension of the front cavity along the thickness direction X, the larger the resonance frequency corresponding to the corresponding resonance peak of the front cavity, and the flatter the frequency response curve in the low frequency band range (e.g., 100Hz to 1000Hz). In some embodiments, the sound output hole is acoustically coupled to the front cavity, and the sound in the front cavity is transmitted to the user's ear canal through the sound output hole and received by the user's hearing system. If the dimension of the sound generating unit 11 in the thickness direction X is too large, the resonance frequency corresponding to the resonance peak of the corresponding front cavity of the sound generating unit 11 is too small, and the overall dimension or weight of the sound generating unit 11 is large in the wearing state, which affects the stability and comfort when wearing. If the dimension of the sound generating unit 11 in the thickness direction X is too large, it affects the acoustic performance of the sound generating unit 11 in the low frequency band. If the dimension of the sound generating unit 11 in the thickness direction X is too small, the space of the front cavity and the rear cavity of the sound generating unit 11 is limited, which affects the amplitude of the diaphragm and limits the output of the sound generating unit 11 at low frequencies. Based on this, in order to ensure that the sound generating unit 11 has a good acoustic output effect and ensures stability when worn, in some embodiments, the thickness of the sound generating unit 11 (the dimension of the sound generating unit 11 along the thickness direction) may be 2 mm to 20 mm. Preferably, the thickness of the sound generating unit 11 may be 5 mm to 15 mm. More preferably, the thickness of the sound generating unit 11 may be set to 8 mm to 12 mm.In addition, when the sound generating unit 11 is worn, if at least one of the two side walls (i.e., the inner surface facing the outside of the user's ear and the outer surface facing away from the outside of the user's ear) arranged opposite each other in the thickness direction X is not flat, the thickness of the sound generating unit 11 may refer to the maximum distance between the inner surface and the outer surface of the sound generating unit 11 in the thickness direction X.

[0060] In the examples of this specification, the frequency response curves corresponding to different measured thicknesses were measured by changing the dimension of the sound generating unit in the thickness direction when the mounting angle (the angle between the upper wall or lower wall and the horizontal direction, for example, the angle between the upper wall and the horizontal direction is 0°) and mounting position of the sound generating unit are constant, and the dimension in the major axis direction and the dimension in the minor axis direction are constant.

[0061] 16A to 16E are exemplary schematic diagrams of an open-type earphone according to some other embodiments of the present specification. As shown in FIG. 16A, FIG. 16D, and FIG. 16E, in some embodiments, in the worn state, the upper wall 111 (also called the upper side) or the lower wall 112 (also called the lower side) of the sound generating unit 11 may be parallel or approximately parallel to a horizontal plane. As shown in FIG. 16A, in some embodiments, the projection of the end FE of the sound generating unit 11 onto the sagittal plane may be located within a region between the projection of the inner contour 1014 of the pinna onto the sagittal plane and the projection of the edge of the cavity of the concha 102 onto the sagittal plane, that is, the midpoint of the projection of the end FE of the sound generating unit 11 onto the sagittal plane is located between the projection of the inner contour 1014 of the pinna onto the sagittal plane and the projection of the edge of the cavity of the concha 102 onto the sagittal plane. 16D, in some embodiments, the end FE of the sound-generating unit 11 may abut an edge of the cavity of the concha 102, the fixed end of the sound-generating unit 11 may be located in front of the tragus, and at least a portion of the sound-generating unit 11 may cover the user's cavity of the concha 102. As shown in FIG 16E, in some embodiments, the midpoint of the projection of the end FE of the sound-generating unit 11 onto the sagittal plane may be located within the region of the projection of the cavity of the concha 102 onto the sagittal plane, and the projection of the fixed end of the sound-generating unit 11 onto the sagittal plane may be located outside the region of the projection of the user's pinna onto the sagittal plane.

[0062] As shown in Figures 16B and 16C, in some embodiments, in the worn state, the upper wall 111 or the lower wall 112 of the sound generating unit 11 may be inclined at a certain angle with respect to the horizontal plane. As shown in Figure 16B, in some embodiments, the end FE of the sound generating unit 11 may be inclined to the region of the top of the auricle with respect to the fixed end of the sound generating unit 11, and the end FE of the sound generating unit 11 may abut against the inner contour 1014 of the auricle. As shown in Figure 16C, in some embodiments, the fixed end of the sound generating unit 11 may be inclined to the region of the top of the auricle with respect to the end FE of the sound generating unit 11, and the end FE of the sound generating unit 11 may be located between the edge of the concha cavity 102 and the inner contour 1014 of the auricle, that is, the midpoint C3 of the projection of the end FE of the sound generating unit 11 onto the sagittal plane is located between the projection of the inner contour 1014 of the auricle onto the sagittal plane and the projection of the edge of the concha cavity 102 onto the sagittal plane.

[0063] As can be understood, when the user wears the earphones, if the distance between the midpoint C3 of the projection of the end FE of the sound generating unit 11 onto the sagittal plane and the projection of the inner contour 1014 of the pinna onto the sagittal plane is too large, the end FE of the sound generating unit 11 cannot abut against the inner contour 1014 of the pinna, and thus cannot play the role of positional restriction for the sound generating unit 11 and is prone to coming off. Also, if the distance between the centroid O of the first projection and a point in a specific area of ​​the boundary of the second projection is too large, a gap may be formed between the end FE of the sound generating unit 11 and the inner contour 1014 of the pinna, and the sound emitted from the sound emission hole and the sound emitted from the decompression hole will be acoustically short-circuited in the area between the end FE of the sound generating unit 11 and the inner contour 1014 of the pinna, so that the listening volume at the user's ear canal mouth will be reduced, and the larger the area between the end FE of the sound generating unit 11 and the inner contour 1014 of the pinna, the more obvious the acoustic short-circuit phenomenon will be. The inner contour 1014 of the pinna may refer to the inner wall of the helix, and accordingly, the outer contour 1013 of the pinna may refer to the outer wall of the helix. In some embodiments, in order to ensure that the open-type earphone has excellent stability when worn, the distance between the midpoint C3 of the projection of the end FE of the sound generating unit 11 onto the sagittal plane and the projection of the inner contour 1014 of the pinna onto the sagittal plane may be 8 mm or less. Preferably, the distance between the midpoint C3 of the projection of the end FE of the sound generating unit 11 onto the sagittal plane and the projection of the inner contour 1014 of the pinna onto the sagittal plane may be 0 mm to 6 mm. More preferably, the distance between the midpoint C3 of the projection of the end FE of the sound generating unit 11 onto the sagittal plane and the projection of the inner contour 1014 of the pinna onto the sagittal plane may be 0 mm to 5.5 mm. In some embodiments, the distance between the midpoint C3 of the projection of the end FE of the sound generating unit 11 onto the sagittal plane and the projection of the inner contour 1014 of the pinna onto the sagittal plane may be 0, and when the distance is 0, it indicates that the end FE of the sound generating unit 11 abuts against the inner contour 1014 of the pinna, and at this time, the sound generating unit 11 abuts against the inner contour 1014 of the pinna in the worn state, thereby improving the stability when the open-type earphone is worn. In addition, by making the area between the end FE of the sound generating unit 11 and the inner contour 1014 of the pinna as small as possible and reducing the acoustic short-circuit area around the sound generating unit 11, the listening volume at the user's ear canal can be increased.In a specific scenario, a point other than the midpoint C3 of the projection of the end FE of the sound generating unit 11 onto the sagittal plane may abut on an edge of the inner contour 1014 of the pinna, and in this case, the distance between the midpoint C3 of the projection of the end FE of the sound generating unit 11 onto the sagittal plane and the projection of the inner contour 1014 of the pinna onto the sagittal plane may be greater than 0 mm. In some embodiments, the distance between the midpoint C3 of the projection of the end FE of the sound generating unit 11 onto the sagittal plane and the projection of the inner contour 1014 of the pinna onto the sagittal plane may be 2 mm to 10 mm. Preferably, the distance between the midpoint C3 of the projection of the end FE of the sound generating unit 11 onto the sagittal plane and the projection of the inner contour 1014 of the pinna onto the sagittal plane may be 4 mm to 8 mm.

[0064] In this specification, the end FE of the sound generating unit 11 refers to one end of the sound generating unit 11 that is distant from the connection point between the sound generating unit 11 and the ear hook, and when the projection of the end FE of the sound generating unit 11 onto the sagittal plane is a curved line or a broken line, the midpoint C3 of the projection of the end FE of the sound generating unit 11 onto the sagittal plane can be selected by the following exemplary method. A line segment is drawn by selecting the start point and end point of the projection of the end FE onto the sagittal plane, and a perpendicular bisector is drawn by selecting the midpoint of the line segment, and the point where the perpendicular bisector intersects with the projection is the midpoint C3 of the projection of the end of the sound generating unit 11 onto the sagittal plane. In some embodiments, when the end FE of the sound generating unit 11 is a curved surface, a tangent line of the projection parallel to the minor axis direction Z may be selected to be the midpoint of the projection of the end FE of the sound generating unit 11 onto the sagittal plane.

[0065] Also, in some embodiments of the present specification, the distance between the midpoint of the projection of the end FE of the sound generating unit 11 onto the sagittal plane and the projection of the inner contour 1014 of the pinna onto the sagittal plane may refer to the minimum distance between the area of ​​the projection of the end FE of the sound generating unit 11 onto the sagittal plane and the projection of the inner contour 1014 of the pinna onto the sagittal plane. Alternatively, the distance between the midpoint C3 of the projection of the end FE of the sound generating unit 11 onto the sagittal plane and the projection of the inner contour 1014 of the pinna onto the sagittal plane may refer to the distance on the sagittal axis between the midpoint C3 of the projection of the end FE of the sound generating unit 11 onto the sagittal plane and the projection of the inner contour 1014 of the pinna onto the sagittal plane.

[0066] The length of the baffle formed by the sound generating unit 11 and the antihelix region is related to the range of the distance between the midpoint C3 of the projection of the end FE of the sound generating unit 11 onto the sagittal plane and the projection of the inner contour 1014 of the pinna onto the sagittal plane; for example, the smaller the distance between the midpoint C3 of the projection of the end FE of the sound generating unit 11 onto the sagittal plane and the projection of the inner contour 1014 of the pinna onto the sagittal plane, the longer the baffle formed by the sound generating unit 11 and the antihelix region, and the greater the difference in acoustic distance between the sound emission hole and the decompression hole to the external auditory canal 101, and the higher the intensity of the sound received in the external auditory canal 101. Also, the inclination angle of the projection of the upper wall 111 or the lower wall 112 of the sound generating unit 11 onto the sagittal plane with respect to the horizontal direction affects the position of the sound output hole with respect to the ear canal opening, and for example, the smaller the inclination angle of the projection of the upper wall 111 or the lower wall 112 of the sound generating unit 11 onto the sagittal plane with respect to the horizontal direction, the closer the sound output hole is to the ear canal opening. Hereinafter, a specific description will be given with reference to Figs. 16A to 16E.

[0067] In some embodiments, the shape of the sound generating unit 11 may be a regular shape such as a rectangular parallelepiped, an approximately rectangular parallelepiped (e.g., racetrack-shaped), or a cylindrical body, or other irregular shapes. As shown in Figs. 16A, 16D, and 16E, in some embodiments, when the sound generating unit 11 has an approximately rectangular parallelepiped structure, the upper wall 111 or the lower wall 112 of the sound generating unit 11 may be parallel or approximately parallel to the horizontal direction in the worn state. In this case, the range of the inclination angle of the projection of the upper wall 111 or the lower wall 112 of the sound generating unit 11 onto the sagittal plane with respect to the horizontal direction may be 0° to 20°, and the range of the distance between the midpoint C3 of the projection of the end FE of the sound generating unit 11 onto the sagittal plane and the projection of the inner contour 1014 of the pinna onto the sagittal plane is 0 mm to 18 mm. 16A, the range of the inclination angle of the projection of the upper wall 111 or the lower wall 112 of the sound generating unit 11 onto the sagittal plane with respect to the horizontal direction may be 5° to 15°, and the distance between the midpoint C3 of the projection of the end FE of the sound generating unit 11 onto the sagittal plane and the projection of the inner contour 1014 of the pinna onto the sagittal plane may be 0 mm to 11 mm. When the mounting method shown in FIG. 16D is used, the range of the inclination angle of the projection of the upper wall 111 or the lower wall 112 of the sound generating unit 11 onto the sagittal plane with respect to the horizontal direction may be 7° to 12°, and the distance between the midpoint C3 of the projection of the end FE of the sound generating unit 11 onto the sagittal plane and the projection of the inner contour 1014 of the pinna onto the sagittal plane may be 3 mm to 12 mm. 16E is used, the range of the inclination angle of the projection of the upper wall 111 or the lower wall 112 of the sound generating unit 11 onto the sagittal plane with respect to the horizontal direction may be 8° to 10°, and the distance between the midpoint C3 of the projection of the end FE of the sound generating unit 11 onto the sagittal plane and the projection of the inner contour 1014 of the pinna onto the sagittal plane may be 8 mm to 12 mm. In some embodiments, when the open-type earphone is in a worn state, the end FE of the sound generating unit 11 may abut against the inner contour 1014 of the pinna, and the ear hook may fit behind the user's ear, whereby the sound generating unit 11 and the ear hook engage with each other to hold the user's ear from both the front and rear, increasing the resistance that prevents the open-type earphone 10 from coming off the ear, and improving the stability of the open-type earphone 10 when worn.

[0068] 16B and 16C, in some embodiments, the upper wall 111 or the lower wall 112 of the sound generating unit 11 may be inclined at a certain angle with respect to the horizontal plane, but if the inclination angle of the upper wall 111 or the lower wall 112 of the sound generating unit 11 with respect to the horizontal plane is too large, the sound generating unit 11 may come out of the user's auricle, causing discomfort and instability when worn. Therefore, in order to ensure that the area of ​​the sound generating unit 11 covers the antihelix region, increase the intensity of the sound at the ear canal opening, and ensure that the open-type earphone has excellent stability and comfort when worn, in some embodiments, when the open-type earphone 10 is in a worn state, the inclination angle of the upper wall 111 or the lower wall 112 of the sound generating unit 11 between the projection onto the sagittal plane and the horizontal direction may be 43° or less. 16B and 16C, the range of the inclination angle of the projection of the upper wall 111 or the lower wall 112 of the sound generating unit 11 onto the sagittal plane with respect to the horizontal direction may be 0° to 43°, and the range of the distance between the midpoint C3 of the projection of the end FE of the sound generating unit 11 onto the sagittal plane and the projection of the inner contour 1014 of the pinna onto the sagittal plane may be 0 mm to 15 mm. Exemplarily, when the mounting method shown in FIG. 16B is used, the range of the inclination angle of the projection of the upper wall 111 or the lower wall 112 of the sound generating unit 11 onto the sagittal plane with respect to the horizontal direction may be 30° to 45°, and the distance between the midpoint C3 of the projection of the end FE of the sound generating unit 11 onto the sagittal plane and the projection of the inner contour 1014 of the pinna onto the sagittal plane may be 0 mm to 10 mm. When using the mounting method shown in Figure 16C, the range of the inclination angle of the projection of the upper wall 111 or the lower wall 112 of the sound generating unit 11 onto the sagittal plane with respect to the horizontal direction may be 25° to 45°, and the distance between the midpoint C3 of the projection of the end portion FE of the sound generating unit 11 onto the sagittal plane and the projection of the inner contour 1014 of the auricle onto the sagittal plane may be 3 mm to 11 mm.

[0069] The inclination angle between the projection of the upper wall 111 of the sound generating unit 11 onto the sagittal plane and the horizontal direction may be the same as or different from the inclination angle between the projection of the lower wall 112 onto the sagittal plane and the horizontal direction. For example, when the upper wall 111 of the sound generating unit 11 is parallel to the lower wall 112, the inclination angle between the projection of the upper wall 111 onto the sagittal plane and the horizontal direction is the same as the inclination angle between the projection of the lower wall 112 onto the sagittal plane and the horizontal direction. Also, for example, when the upper wall 111 of the sound generating unit 11 is not parallel to the lower wall 112, or when one of the upper wall 111 or the lower wall 112 is a flat wall and the other is a non-flat wall (e.g., a curved wall), the inclination angle between the projection of the upper wall 111 onto the sagittal plane and the horizontal direction may be different from the inclination angle between the projection of the lower wall 112 onto the sagittal plane and the horizontal direction. Furthermore, when the upper wall 111 or the lower wall 112 is a curved or uneven surface, the projection of the upper wall 111 or the lower wall 112 onto the sagittal plane may be a curve or a broken line, and in this case, the inclination angle between the projection of the upper wall 111 onto the sagittal plane and the horizontal direction may be the included angle between the tangent of the curve or broken line at the point where the distance to the ground is maximum and the horizontal direction, and the inclination angle between the projection of the lower wall 112 onto the sagittal plane and the horizontal direction may be the included angle between the tangent of the curve or broken line at the point where the distance to the ground is minimum and the horizontal direction.

[0070] In addition, the sound generating unit 11 of the open-type earphone shown in Figure 14 does not need to cover the antihelix region, and is in the wearing position shown in Figure 16E, for example. At this time, the sound generating unit 11 does not enter the cavum of the concha, and the side wall facing the outside of the user's ear is suspended relative to the cavum of the concha of the user. In other words, the sound generating unit 11 itself functions as a baffle, and the greater the overlap rate between the area of ​​the first projection of the sound generating unit 11 onto the sagittal plane and the area of ​​the projection of the cavum of the concha onto the sagittal plane, the closer the sound emission hole of the sound generating unit 11 is to the ear canal opening, and the louder the listening volume at the user's ear canal opening. Here, the distance between the projection of the end of the sound generating unit 11 onto the sagittal plane and the projection of the edge of the cavity of the concha onto the sagittal plane shows a positive correlation with the overlapping ratio between the area of ​​the first projection of the sound generating unit 11 onto the sagittal plane and the area of ​​the projection of the cavity of the concha onto the sagittal plane, and further, the position of the sound output hole of the sound generating unit 11 relative to the ear canal opening shows a positive correlation with the distance between the projection of the end of the sound generating unit 11 onto the sagittal plane and the projection of the edge of the cavity of the concha onto the sagittal plane. A specific description will be given below with reference to FIG. 17.

[0071] 17 is a schematic diagram of exemplary frequency response curves corresponding to different distances between the projection of the end of the sound generating unit 11 on the sagittal plane and the projection of the edge of the cavity of the concha on the sagittal plane in FIG. 16E. As shown in FIG. 17, the horizontal axis indicates frequency (unit: Hz), and the vertical axis indicates sound pressure level (unit: dB) at the ear canal opening at different frequencies. Curve 1801 is a frequency response curve corresponding to the case where the distance between the projection of the end of the sound generating unit 11 on the sagittal plane and the projection of the edge of the cavity of the concha on the sagittal plane is 0, curve 1802 is a frequency response curve corresponding to the case where the distance between the projection of the end of the sound generating unit 11 on the sagittal plane and the projection of the edge of the cavity of the concha on the sagittal plane is 3.72 mm, and curve 1803 is a frequency response curve corresponding to the case where the distance between the projection of the end of the sound generating unit 11 on the sagittal plane and the projection of the edge of the cavity of the concha on the sagittal plane is 10.34 mm. As can be seen from FIG. 17, the frequency response when the distance between the projection of the end of the sound generating unit 11 on the sagittal plane and the projection of the edge of the cavity of the concha on the sagittal plane is 0 mm and 3.72 mm is better than the frequency response when the distance is 10.34 mm. Based on this, in some embodiments, in order to ensure that the open-type earphone 10 has a good listening effect, the distance between the projection of the end FE of the sound generating unit 11 on the sagittal plane and the projection of the edge of the cavity of the concha on the sagittal plane may be 10.34 mm or less. Preferably, the distance between the projection of the end FE of the sound generating unit 11 on the sagittal plane and the projection of the edge of the cavity of the concha on the sagittal plane may be 0 mm to 7 mm. More preferably, the distance between the projection of the end FE of the sound generating unit 11 on the sagittal plane and the projection of the edge of the cavity of the concha on the sagittal plane may be 0 mm to 5 mm. More preferably, the distance between the projection of the end FE of the sound generating unit 11 onto the sagittal plane and the projection of the edge of the cavity of the concha onto the sagittal plane may be 0 mm to 3.72 mm. In a specific scenario, a point other than the midpoint C3 of the projection of the end FE of the sound generating unit 11 onto the sagittal plane may abut the edge of the cavity of the concha, and in this case, the distance between the midpoint C3 of the projection of the end FE of the sound generating unit 11 onto the sagittal plane and the projection of the edge of the cavity of the concha onto the sagittal plane may be greater than 0 mm. In some embodiments, the distance between the midpoint C3 of the projection of the end FE of the sound generating unit 11 onto the sagittal plane and the projection of the edge of the cavity of the concha onto the sagittal plane may be 2 mm to 7 mm.Preferably, the distance between the midpoint C3 of the projection of the end FE of the sound generating unit 11 onto the sagittal plane and the projection of the edge of the cavity of the concha onto the sagittal plane may be 2 mm to 3.74 mm. Note that in the examples of this specification, the frequency response curves corresponding to different distances between the midpoint of the projection of the end FE of the sound generating unit onto the sagittal plane and the projection of the edge of the cavity of the concha onto the sagittal plane were measured by changing the mounting position of the sound generating unit (for example, by translating it along the sagittal axis direction) when the mounting angle of the sound generating unit (the included angle between the upper or lower wall and the horizontal direction, for example, the included angle between the upper wall and the horizontal direction is 0°), the dimension in the major axis direction, the dimension in the minor axis direction, and the dimension in the thickness direction are constant.

[0072] As shown in Figures 16A to 16C, when the dimensions of the sound generating unit 11 and the user's auricle are constant and the inclination angle of the sound generating unit 11 relative to the horizontal direction when worn is constant, the distance between the centroid O of the first projection of the sound generating unit 11 onto the sagittal plane and the centroid Q of the projection of the ear canal opening (for example, the dotted area 1016 shown in Figures 16A to 16E) onto the sagittal plane affects the role of the baffle formed by the sound generating unit 11 and the antihelix region, and the position of the sound emission hole of the sound generating unit 11 relative to the ear canal opening, and ultimately affects the intensity of the sound at the ear canal opening. For example, the smaller the distance between the centroid O of the first projection of the sound generating unit 11 onto the sagittal plane and the centroid Q of the projection of the ear canal opening onto the sagittal plane, the smaller the contact area between the sound generating unit 11 and the antihelical region, and the weaker the role of the baffle formed by the sound generating unit 11 and the antihelical region, but at this time, the greater the overlap ratio between the area of ​​the first projection of the sound generating unit 11 onto the sagittal plane and the area of ​​the projection of the cavity of the concha onto the sagittal plane, the closer the sound output hole of the sound generating unit 11 is to the ear canal opening, which also means that the listening effect at the ear canal opening can be improved. Therefore, on the premise that the overall volume and wearing method of the sound generating unit 11 are constant, it is also necessary to give careful consideration to the distance between the centroid O of the first projection of the sound generating unit 11 onto the sagittal plane and the centroid Q of the projection of the ear canal opening onto the sagittal plane.

[0073] FIG. 18A is a schematic diagram of an exemplary frequency response curve corresponding to different overlapping percentages between the area of ​​the first projection of the sound generating unit 11 onto the sagittal plane and the area of ​​the projection of the concha cavity onto the sagittal plane in a wearing scenario in which the sound generating unit 11 according to some other embodiments of the present specification does not enter the concha cavity, and FIG. 18B is a schematic diagram of an exemplary frequency response curve corresponding to different distances between the centroid of the first projection of the sound generating unit 11 onto the sagittal plane and the centroid of the projection of the ear canal opening onto the sagittal plane in a wearing scenario in which the sound generating unit 11 according to some other embodiments of the present specification does not enter the concha cavity.

[0074] As shown in FIG. 18A, the horizontal axis represents the overlap ratio between the area of ​​the first projection of the sound generating unit 11 onto the sagittal plane and the area of ​​the projection of the cavity of the concha onto the sagittal plane, and the vertical axis represents the sound pressure level of the sound at the ear canal opening corresponding to different overlap ratios. Line 1601 represents a linear relationship obtained by simulating the overlap ratio between the area of ​​the first projection and the area of ​​the projection of the cavity of the concha onto the sagittal plane and the sound pressure level at the ear canal opening when the frequency is 500 Hz. Line 1602 represents a linear relationship obtained by simulating the overlap ratio between the area of ​​the first projection and the area of ​​the projection of the cavity of the concha onto the sagittal plane and the sound pressure level at the ear canal opening when the frequency is 1 kHz. Line 1603 represents a linear relationship obtained by simulating the overlap ratio between the area of ​​the first projection and the area of ​​the projection of the cavity of the concha onto the sagittal plane and the sound pressure level at the ear canal opening when the frequency is 3 kHz. The white circles in FIG. 18A show test data corresponding to different overlap percentages between the area of ​​the first projection and the area of ​​the projection of the cavity of the concha onto the sagittal plane when the frequency is 500 Hz, the black circles in FIG. 18A show test data corresponding to different overlap percentages between the area of ​​the first projection and the area of ​​the projection of the cavity of the concha onto the sagittal plane when the frequency is 1 kHz, and the gray circles in FIG. 18A show test data corresponding to different overlap percentages between the area of ​​the first projection and the area of ​​the projection of the cavity of the concha onto the sagittal plane when the frequency is 3 kHz. As can be seen from Figure 18A, when the frequency is different, the overlap ratio between the area of ​​the first projection and the area of ​​the projection onto the sagittal plane of the cavity of the concha shows an almost linear change with the magnitude of the sound pressure level at the opening of the user's ear canal, and when the overlap ratio between the area of ​​the first projection onto the sagittal plane of the sound generating unit 11 and the area of ​​the projection onto the sagittal plane of the cavity of the concha is greater than 10%, the sound of a specific frequency (e.g., 500 Hz, 1 kHz, 3 kHz) measured at the opening of the ear canal is clearly increased compared to when there is no overlap ratio between the area of ​​the first projection onto the sagittal plane of the sound generating unit 11 and the area of ​​the projection onto the sagittal plane of the cavity of the concha (the overlap ratio is 0).In addition, if the overlap ratio between the area of ​​the first projection of the sound generating unit 11 on the sagittal plane and the area of ​​the projection of the cavity of the concha on the sagittal plane is too large, it may affect the opening state of the ear canal opening and further affect the user's acquisition of sound from the external environment. Therefore, the overlap ratio between the area of ​​the first projection of the sound generating unit 11 on the sagittal plane and the area of ​​the projection of the cavity of the concha on the sagittal plane should not be too large. For example, the overlap ratio between the area of ​​the first projection of the sound generating unit 11 on the sagittal plane and the area of ​​the projection of the cavity of the concha on the sagittal plane is 62% or less. Based on this, in order to ensure the sound output quality of the sound generating unit 11, the overlap ratio between the first projection of the sound generating unit 11 on the sagittal plane and the projection of the cavity of the concha on the sagittal plane may be 10% to 60%. Preferably, the overlapping ratio between the first projection of the sound generating unit 11 onto the sagittal plane and the projection of the cavity of the concha onto the sagittal plane may be 10% to 45%. More preferably, the overlapping ratio between the first projection of the sound generating unit 11 onto the sagittal plane and the projection of the cavity of the concha onto the sagittal plane may be 11.82% to 40%. Preferably, the overlapping ratio between the first projection of the sound generating unit 11 onto the sagittal plane and the projection of the cavity of the concha onto the sagittal plane may be 18% to 38%. More preferably, the overlapping ratio between the first projection of the sound generating unit 11 onto the sagittal plane and the projection of the cavity of the concha onto the sagittal plane may be 25% to 38%.

[0075] As shown in FIG. 18B, the horizontal axis is the distance between the centroid O of the first projection of the sound generating unit 11 onto the sagittal plane and the centroid Q of the projection of the ear canal opening onto the sagittal plane, and the vertical axis is the frequency response sound pressure level of the sound at the ear canal opening corresponding to different distances. Line 1604 indicates a linear relationship between the distance between the centroid O of the first projection of the sound generating unit 11 onto the sagittal plane and the centroid Q of the projection of the ear canal opening onto the sagittal plane and the sound pressure level at the ear canal opening when the frequency is 500 Hz under ideal conditions, line 1605 indicates a linear relationship between the distance between the centroid O of the first projection of the sound generating unit 11 onto the sagittal plane and the centroid Q of the projection of the ear canal opening onto the sagittal plane and the sound pressure level at the ear canal opening when the frequency is 1 kHz, and line 1606 indicates a linear relationship between the distance between the centroid O of the first projection of the sound generating unit 11 onto the sagittal plane and the centroid Q of the projection of the ear canal opening onto the sagittal plane and the sound pressure level at the ear canal opening when the frequency is 3 kHz. The white circles in Figure 18B show test data corresponding to different distances between the centroid O of the first projection of the sound generating unit 11 onto the sagittal plane and the centroid Q of the projection of the ear canal opening onto the sagittal plane when the frequency is 500 Hz, the black circles in Figure 18B show test data corresponding to different distances between the centroid O of the first projection of the sound generating unit 11 onto the sagittal plane and the centroid Q of the projection of the ear canal opening onto the sagittal plane when the frequency is 1 kHz, and the grey circles in Figure 18B show test data corresponding to different distances between the centroid O of the first projection of the sound generating unit 11 onto the sagittal plane and the centroid Q of the projection of the ear canal opening onto the sagittal plane when the frequency is 3 kHz. As can be seen from Figure 18B, when the frequency is different, the distance between the centroid O of the first projection of the sound generating unit 11 onto the sagittal plane and the centroid Q of the projection of the ear canal opening onto the sagittal plane shows an almost negative correlation with the magnitude of the sound pressure level at the user's ear canal opening, and overall, the sound pressure level of a sound of a specific frequency (e.g., 500 Hz, 1 kHz, 3 kHz) measured at the ear canal opening decreases as the distance between the centroid O of the first projection of the sound generating unit 11 onto the sagittal plane and the centroid Q of the projection of the ear canal opening onto the sagittal plane increases, and as shown in Figures 18A and 18B, the greater the distance between the centroid O of the first projection of the sound generating unit 11 onto the sagittal plane and the centroid Q of the projection of the ear canal opening onto the sagittal plane, the smaller the overlap ratio between the area of ​​the first projection of the sound generating unit 11 onto the sagittal plane and the area of ​​the projection of the ear canal opening onto the sagittal plane. The overlapping ratio affects the relative position between the sound output hole of the sound generating unit 11 and the ear canal opening.For example, the greater the distance between the centroid O of the first projection of the sound generating unit 11 onto the sagittal plane and the centroid Q of the projection of the ear canal opening onto the sagittal plane, the greater the overlap ratio, and at this time, the sound emission hole of the sound generating unit 11 is closer to the ear canal opening, and the listening effect at the ear canal opening is also improved. Also, if the distance between the centroid O of the first projection of the sound generating unit 11 onto the sagittal plane and the centroid Q of the projection of the ear canal opening onto the sagittal plane is too small, the overlap ratio between the area of ​​the first projection of the sound generating unit 11 onto the sagittal plane and the area of ​​the projection of the ear canal opening onto the sagittal plane becomes too large, and the sound generating unit 11 may cover the user's ear canal opening, affecting the user's acquisition of sound information from the external environment. As can be seen from Fig. 18B, taking the frequency as an example of 3kHz, when the distance between the centroid O of the first projection of the sound generating unit 11 onto the sagittal plane and the centroid Q of the projection of the ear canal opening onto the sagittal plane is 4mm, 5.8mm, 12mm, the measured sound pressure levels at the ear canal opening are -73dB, -76dB, -82dB, respectively, and when the distance between the centroid O of the first projection of the sound generating unit 11 onto the sagittal plane and the centroid Q of the projection of the ear canal opening onto the sagittal plane is 17mm, 22mm, the measured sound pressure levels at the ear canal opening are -85dB, -83dB, respectively. As can be seen from the above, the distance between the centroid O of the first projection of the sound generating unit 11 onto the sagittal plane and the centroid Q of the projection of the ear canal opening onto the sagittal plane should not be too large. In some embodiments, in order to ensure that the open-type earphone has a good sound output quality in a worn state (e.g., a sound pressure level at the ear canal opening is greater than -82 dB) and also ensure that the user can receive audio information from the external environment, the distance between the centroid O of the first projection of the sound generating unit 11 onto the sagittal plane and the centroid Q of the projection of the ear canal opening onto the sagittal plane may be 3 mm to 13 mm. Preferably, the distance between the centroid O of the first projection of the sound generating unit 11 onto the sagittal plane and the centroid Q of the projection of the ear canal opening onto the sagittal plane may be 4 mm to 10 mm. Preferably, the distance between the centroid O of the first projection of the sound generating unit 11 onto the sagittal plane and the centroid Q of the projection of the ear canal opening onto the sagittal plane may be 4 mm to 7 mm. Preferably, the distance between the centroid O of the first projection of the sound generating unit 11 onto the sagittal plane and the centroid Q of the projection of the ear canal opening onto the sagittal plane may be 4 mm to 6 mm.

[0076] In the examples of this specification, the frequency response curves corresponding to the different measured overlap ratios and the frequency response curves corresponding to the distance from the centroid of the first projection to the centroid of the projection of the auditory canal opening onto the sagittal plane were measured by changing the mounting position of the sound generating unit (e.g., moving it parallel along the sagittal axis direction) when the mounting angle of the sound generating unit (the included angle between the upper or lower wall and the horizontal direction, for example, the included angle between the upper wall and the horizontal direction is 0°), the dimension in the major axis direction, the dimension in the minor axis direction, and the dimension in the thickness direction are constant.

[0077] Although the basic concept has been described above, it is clear to those skilled in the art that the detailed disclosure above is merely presented as an example and does not limit the present application. Although not explicitly described in this specification, those skilled in the art can make various changes, improvements and modifications to the present application. These changes, improvements and modifications are intended to be suggested by the present application and therefore are within the spirit and scope of the exemplary embodiments of the present application.

[0078] Furthermore, certain terms are used herein to describe embodiments of the present application. For example, "one embodiment," "an embodiment," and / or "some embodiments" refer to a particular feature, structure, or characteristic associated with at least one embodiment of the present application. Thus, it is emphasized and understood that two or more references to "one embodiment" or "one embodiment" or "one alternative embodiment" in different parts of this specification do not necessarily refer to the same embodiment. Also, certain features, structures, or characteristics in one or more embodiments of the present application may be combined as appropriate.

[0079] Similarly, in the foregoing description of embodiments of the present application, various features may be grouped together in a single embodiment, figure, or description for the purpose of simplifying the description of the present disclosure and facilitating an understanding of one or more embodiments of the present invention. However, this method of disclosure should not be interpreted as reflecting an intention that the subject matter of the present application requires more features than are recited in each claim. Rather, an embodiment may include fewer than all features of a single embodiment disclosed above.

[0080] Finally, it should be understood that the embodiments described herein are merely illustrative of the principles of the embodiments of the present application. Other variations may be within the scope of the present application. Thus, by way of example, and not of limitation, alternative configurations of the embodiments of the present application may be considered consistent with the teachings of the present application. Accordingly, the embodiments of the present application are not limited to the embodiments expressly introduced and described herein. [Explanation of symbols]

[0081] 10 Open-type earphones 11, 11A, 11B, 11C Sound generating section 12 Suspension structure 121 First Part 122 Second Part 402 Similar Cavity Structure 403 Leakage Structure 100 ears 101 External auditory canal 102 Concha cavity 103 Concha navicular 104 Triangular fossa 105 Antihelix 106 Scaphoid fossa 107 Earrings 108 Earlobe 109 Helical foot 1013 Outer contour 1014 Inner Contour

Claims

1. A sound generating unit; an ear hook including a first part and a second part connected in sequence, the first part being hung between the auricle and the head of a user, the second part extending toward an anterior outer surface of the auricle, and connected to the sound generating unit, thereby attaching the sound generating unit to a position near an ear canal without blocking the ear canal opening; An open-type earphone, wherein at least a portion of the sound generating unit is inserted into the cavity of the concha, and an overlap rate between an area of ​​the sound generating unit projected onto a sagittal plane and an area of ​​the cavity of the concha projected onto the sagittal plane is 44.01% or more.

2. The open-type earphone according to claim 1 , wherein an overlap rate between an area of ​​the sound generating unit projected onto the sagittal plane and an area of ​​the cavity of the concha projected onto the sagittal plane is 57.89% or more.

3. The area of ​​the projection of the sound generating unit onto the sagittal plane is 202 mm ２ ~560mm ２ 2. The open-type earphone according to claim 1,

4. The open-type earphone according to any one of claims 1 to 3, wherein a distance between a projection of an end of the sound generating unit onto the sagittal plane and a projection of an edge of the cavity of the concha onto the sagittal plane is 16 mm or less.

5. The open-type earphone according to claim 4 , wherein an end of the sound generating unit abuts against an edge of the cavity of the concha.

6. 5. The open-type earphone according to claim 4, wherein the range of the distance between the projection of the end of the sound generating portion onto the sagittal plane and the projection of the edge of the cavity of the concha onto the sagittal plane is 4.77 mm to 10.48 mm.

7. The open-type earphone according to any one of claims 1 to 6, wherein the range of the distance between the centroid of the projection of the sound generating unit onto the sagittal plane and the centroid of the projection of the ear canal opening onto the sagittal plane is 8 mm to 12 mm.

8. The shape of the projection of the sound generating unit onto the sagittal plane includes a major axis portion and a minor axis portion, and the shape of the projection is the range of dimensions of the projection shape along the long axis is 18 mm to 29 mm; The open-type earphone according to any one of claims 1 to 7, wherein the range of dimensions of the projection shape along the minor axis direction is 10 mm to 15 mm.

9. The open-type earphone according to claim 8, wherein a ratio of a dimension of the shape of the projection along the long axis direction to a dimension of the shape of the projection along the short axis direction is 1.4 to 2.

2.

10. 10. The open-type earphone according to claim 1, wherein the sound generating section has a thickness of 6 mm to 12 mm.

11. A sound generating unit; an ear hook including a first part and a second part connected in sequence, the first part being hung between a user's auricle and a head, the second part extending toward an anterior outer surface of the auricle, and connected to the sound generating unit to fix the sound generating unit in a position near an ear canal without blocking the ear canal opening; An open-type earphone, wherein at least a portion of the sound generating unit is inserted into the cavity of the concha, and the distance between a projection of an end of the sound generating unit onto a sagittal plane and a projection of an edge of the cavity of the concha onto the sagittal plane is 16 mm or less.

12. The open-type earphone according to claim 11 , wherein an end of the sound generating unit abuts against an edge of the cavity of the concha.

13. The open-type earphone according to claim 11, wherein the range of the distance between the projection of the end of the sound generating portion onto the sagittal plane and the projection of the edge of the cavity of the concha onto the sagittal plane is 4.77 mm to 10.48 mm.

14. The open-type earphone according to claim 11 , wherein an overlapping ratio between an area of ​​the sound generating unit projected onto the sagittal plane and an area of ​​the cavity of the concha projected onto the sagittal plane is 34.05% or more.

15. The area of ​​the projection of the sound generating unit onto the sagittal plane is 202 mm ２ ~560mm ２ The open-type earphone according to claim 14,

16. The open-type earphone according to any one of claims 11 to 15, wherein the range of the distance between the centroid of the projection of the sound generating unit onto the sagittal plane and the centroid of the projection of the ear canal opening onto the sagittal plane is 8 mm to 12 mm.

17. The shape of the projection of the sound generating unit onto the sagittal plane includes a major axis portion and a minor axis portion, and the shape of the projection is the range of dimensions of the projection shape along the long axis is 18 mm to 29 mm; The open-type earphone according to any one of claims 8 to 11, wherein the range of dimensions of the projection shape along the short axis direction is 10 mm to 15 mm.

18. The open-type earphone according to claim 17, wherein a ratio of a dimension of the shape of the projection along the long axis direction to a dimension of the shape of the projection along the short axis direction is between 1.4 and 2.

2.

19. The open-type earphone according to any one of claims 11 to 18, wherein the thickness of the sound generating section is 6 mm to 12 mm.

20. A sound generating unit; an ear hook including a first part and a second part connected in sequence, the first part being hung between the auricle and the head of a user, the second part extending toward the front outer surface side of the auricle, and connected to the sound generating unit to fix the sound generating unit in a position near the ear canal without blocking the ear canal opening; An open-type earphone, wherein at least a portion of the sound generating unit covers the antihelix region, and an overlap rate between an area of ​​the sound generating unit projected onto a sagittal plane and an area of ​​the concha cavity projected onto the sagittal plane is 11.82% or more.

21. The open-type earphone according to claim 20 , wherein an overlap rate between an area of ​​the sound generating unit projected onto the sagittal plane and an area of ​​the cavity of the concha projected onto the sagittal plane is 31.83% or more.

22. The area of ​​the projection of the sound generating unit onto the sagittal plane is 236 mm ２ ~565mm ２ 21. The open-type earphone according to claim 20,

23. The open-type earphone according to any one of claims 20 to 22, wherein a projection of an end of the sound generating unit onto the sagittal plane is located within a region between a projection of an edge of the cavity of the concha onto the sagittal plane and a projection of an inner contour of the pinna onto the sagittal plane.

24. The open-type earphone according to any one of claims 20 to 23, wherein the distance between the projection of the end of the sound generating unit onto the sagittal plane and the projection of the inner contour of the pinna onto the sagittal plane is 8 mm or less.

25. 25. The open-type earphone of claim 24, wherein an end of the sound generating portion abuts against an inner contour of the pinna.

26. The open-type earphone according to claim 24, wherein, in a worn state, the range of inclination angles of the projection of the upper wall or lower wall of the sound generating unit onto the sagittal plane with respect to the horizontal direction is 28° to 43°, and the distance between the projection of the end of the sound generating unit onto the sagittal plane and the projection of the inner contour of the pinna onto the sagittal plane is 8 mm or less.

27. The open-type earphone according to claim 24, wherein, in a worn state, the range of inclination angles of the projection of the upper wall or lower wall of the sound generating unit onto the sagittal plane with respect to the horizontal direction is 0° to 20°, and the distance between the projection of the end of the sound generating unit onto the sagittal plane and the projection of the inner contour of the pinna onto the sagittal plane is 6 mm or less.

28. The open-type earphone according to any one of claims 20 to 27, wherein the range of the distance between the centroid of the projection of the sound generating unit onto the sagittal plane and the centroid of the projection of the ear canal opening onto the sagittal plane is 4 mm to 7 mm.

29. The shape of the projection of the sound generating unit onto the sagittal plane includes a major axis portion and a minor axis portion, and the shape of the projection is the range of dimensions of the projection shape along the long axis is 21 mm to 33 mm; The open-type earphone according to any one of claims 20 to 28, wherein the range of dimensions of the projection shape along the short axis direction is 11 mm to 18 mm.

30. The open-type earphone according to claim 29, wherein a ratio of a dimension of the shape of the projection along the major axis direction to a dimension of the shape of the projection along the minor axis direction is between 1.4 and 2.

4.

31. The open-type earphone according to any one of claims 20 to 30, wherein the thickness of the sound generating section is 6 mm to 12 mm.

32. A sound generating unit; an ear hook including a first part and a second part connected in sequence, the first part being hung between a user's auricle and a head, the second part extending toward an anterior outer surface of the auricle, and connected to the sound generating unit to fix the sound generating unit in a position near an ear canal without blocking the ear canal opening; An open-type earphone, wherein at least a portion of the sound generating unit covers the antihelix, and the distance between a projection of an end of the sound generating unit onto a sagittal plane and a projection of an inner contour of the pinna onto the sagittal plane is 8 mm or less.

33. 33. The open-type earphone of claim 32, wherein a projection of an end of the sound-generating portion onto the sagittal plane lies within a region between a projection of an edge of the cavity of the concha onto the sagittal plane and a projection of an inner contour of the pinna onto the sagittal plane.

34. The open-type earphone according to claim 32 or 33, wherein an overlap rate between an area of ​​the sound generating unit projected onto the sagittal plane and an area of ​​the cavity of the concha projected onto the sagittal plane is 11.82% or more.

35. The area of ​​the projection of the sound generating unit onto the sagittal plane is 236 mm ２ ~565mm ２ The open-type earphone according to any one of claims 32 to 34,

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