Patent Application
20180227655
This application is based upon and claims the benefit of priority of the prior Japanese Patent Application No. 2017-18921, filed on Feb. 3, 2017, the entire contents of which are incorporated herein by reference.
The embodiments discussed herein are related to an electronic device.
There is known a technology for reducing noise due to wind noise by forming a sound path extending to a sound collection member such that the sound path does not have a linear shape.
However, in a technology of the related art such as that described above, it is difficult to obtain, at the position of a sound collection member, acoustic characteristics with which significant resonance will not occur in up to a high voice frequency band. In recent years, the trend has been toward faster transmission speed in telecommunications and also toward wider bandwidth of voice transmission as a telephone function. In addition, in recent years, a new high-quality audio codec (for example, an enhanced voice services (EVS) codec technology) has been developed by using high-speed transmission such as long term evolution (LTE), and this has enabled sound transmission within a voice frequency band in the range of 50 Hz to 14 kHz, which is a high frequency.
The followings are reference documents:
According to an aspect of the invention, an electronic device includes a housing that has a sound hole formed in an outer surface of the housing, a sound collection member that is disposed in the housing, a sound path that extends from the sound hole to the sound collection member, and a waterproof member that is disposed in the sound path and that reduces a possibility of water reaching the sound collection member via the sound hole, wherein the sound path includes a first path that has a first end coupled to the sound hole and that bends more than once from the first end to a second end of the first path, and a second path that is positioned closer to the sound collection member than the first path is and to which the waterproof member is affixed, the second path extending while having a cross-sectional shape corresponding to a shape of the waterproof member.
The object and advantages of the invention will be realized and attained by means of the elements and combinations particularly pointed out in the claims.
It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory and are not restrictive of the invention, as claimed.
Embodiments will be described in detail below with reference to the accompanying drawings.
The electronic device 1 is a terminal having a communication function and is, for example, a smartphone, a tablet terminal device, a portable game device, or the like.
The electronic device 1 includes a housing 10, the display unit 12, a microphone 14 (an example of a sound collection member), a sound path structure 30, and a waterproof membrane 40 (an example of a waterproof member).
The housing 10 may be formed of a plurality of housing members. A substrate and electronic components (including the microphone 14), which are not illustrated, are disposed in the housing 10. The housing 10 has a sound hole 110 formed in an outer surface of the housing 10. The sound hole 110 is preferably formed in an outer surface of the housing 10, the outer surface being located on the side on which the display unit 12 is present. This is because, in the case where the sound hole 110 is formed in the outer surface of the housing 10 on the side on which the display unit 12 is present, the voice recognition rate and the efficiency of voice transmission when a user is facing a screen are increased. Thus, in the example illustrated in
The display unit 12 is formed of, for example, a liquid crystal panel, an organic electroluminescence (EL) panel, or the like. The display unit 12 may integrally include a touch panel. The display unit 12 forms a surface approximately parallel to the outer surface of the housing 10.
The microphone 14 generates electrical signals (voice signals) corresponding to sound and voice that are transmitted thereto via the sound path structure 30. For example, a condenser microphone using a diaphragm may be used as the microphone 14.
The sound path structure 30 is formed of, for example, the housing 10. However, the housing 10 and another member may cooperate with each other in forming the sound path structure 30.
The sound path structure 30 includes a first sound path 310 and a second sound path 320.
The first sound path 310 extends from a position P1, which is the position of the sound hole 110 formed in the outer surface of the housing 10, to an inner position P2 in the housing 10 by bending more than once. In the example illustrated in
Although the cross-sectional shape (the cross-sectional shape when viewed in a direction in which the first sound path 310 extends) of the first sound path 310 may be any shape, it is preferable that the cross-sectional shape of the first sound path 310 be a quadrangular shape (a square shape or a rectangular shape). In the case where the cross-sectional shape of the first sound path 310 is a quadrangular shape, dimensional control may be easily performed, and the first sound path 310 may be the most easily manufactured. Each dimension of the cross-sectional shape of the first sound path 310 is set to 5 mm or less. For example, when the cross-sectional shape of the first sound path 310 has a length a [mm] and a width b [mm], each of the dimensions a and b is set to 5 mm or less. For example, the dimensions a and b are 0.8 and 1.0, respectively.
The second sound path 320 is connected to the first sound path 310 at the inner position P2. The second sound path 320 is a portion that forms a space in which the waterproof membrane 40 is to be disposed. The second sound path 320 extends in the Z direction. A first end (an end on a Z2 side) of the second sound path 320 is connected to the first sound path 310 at the inner position P2, and a second end (an end on the Z1 side) of the second sound path 320 extends to a position P3, which is the position of the microphone 14. Although the second sound path 320 linearly extends without bending, the second sound path 320 may bend in a modification.
As will be described later, the cross-sectional shape (the cross-sectional shape when viewed in the Z direction) of the second sound path 320 corresponds to the shape of the waterproof membrane 40 and is, for example, a quadrangular shape (a square shape or a rectangular shape). In addition, the second sound path 320 extends with a uniform cross section in the Z direction. Thus, the second sound path 320 is formed in a rectangular parallelepiped shape or a cubic shape.
Each dimension of the cross-sectional shape of the second sound path 320 is set to 5 mm or less. For example, when the second sound path 320 is formed in a rectangular parallelepiped shape having a length c [mm] and a width d [mm], each of the dimensions c and d is set to 5 mm or less.
The sound path structure 30 is fabricated so as not to have a straight path having a length of greater than 5 mm in any direction. More specifically, as described above, each of the dimensions of the cross-sectional shapes of the first sound path 310 and the second sound path 320 is set to 5 mm or less. In addition, the lengths of the portions 310-1 and 310-2 of the first sound path 310 are each set to 5 mm or less.
The waterproof membrane 40 is in the form of a sheet and has a waterproof function. The waterproof membrane 40 may be formed by using, for example, a product known under the trade name of “GORE (Registered Trademark) Acoustic Vent GAW331” or the like. The waterproof membrane 40 is affixed to the second sound path 320 of the sound path structure 30. As a result, water that flows along the sound path structure 30 toward the microphone 14 is interrupted by the waterproof membrane 40, so that the microphone 14 may be protected against the water. For example, the waterproof membrane 40 has a size of about 3 mm×about 3 mm and is significantly greater than the cross-sectional shape of the first sound path 310. The dimensions of the cross-sectional shape (the cross-sectional shape when viewed in the Z direction) of the second sound path 320 are set in accordance with the size of the waterproof membrane 40 in such a manner as to enable the waterproof membrane 40 to be affixed to the second sound path 320. Thus, each of the dimensions of the cross-sectional shape (the cross-sectional shape when viewed in the Z direction) of the second sound path 320 is, for example, about 3 mm. In other words, the cross-sectional shape of the second sound path 320 is a shape slightly smaller than the shape of the waterproof membrane 40 due to the fact that the outer peripheral portion of the waterproof membrane 40 is held at the inner periphery of the second sound path 320. This implies that the cross-sectional shape is significantly greater than the cross-sectional shape of the first sound path 310 having a size of, for example, about 0.8 mm×about 1.0 mm.
As described above, the trend in recent years has been toward faster transmission speed in telecommunications and also toward wider bandwidth of voice transmission as a telephone function. In recent years, a new high-quality audio codec has been developed by using high-speed transmission such as LTE, and for example, an EVS codec technology enables sound transmission within a voice frequency band in the range of 50 Hz to 14 kHz, which is a high frequency.
Regarding this, according to the first embodiment, by providing the above-described sound path structure 30, acoustic characteristics with which resonance will not occur at up to 16 kHz may be obtained at the position of the microphone 14 (see the position P3). In other words, acoustic characteristics with which resonance will not occur at any frequency within the voice frequency band in the range of 50 Hz to 14 kHz may be obtained at the position of the microphone 14.
More specifically, acoustic resonance is likely to occur at ¼ wavelength. When a sound speed c is 343.6 m/s (at 20 degrees), the following formula holds true: ¼ wavelength=c/f/4, where f stands for frequency [Hz]. When f is 14, ¼ wavelength is 6.1 mm as expressed by the following formula: ¼ wavelength=343.6 m/s/14 kHz/4=6.1 mm. As other examples, for reference, ¼ wavelength when f is 16, ¼ wavelength when f is 18, and ¼ wavelength when f is 20 are as follows: ¼ wavelength at 16 kHz=5.4 mm, ¼ wavelength at 18 kHz=4.8 mm, and ¼ wavelength at 20 kHz=4.3 mm. The above leads to the fact that a value of less than 5.4 mm is preferable in order not to cause resonance at 16 kHz and that an appropriate value is 5 mm or less considering variations in the sound speed depending on temperature, the accuracy with which a structure is fabricated, and the like. In other words, when the length of the longest straight path in the sound path structure 30 is denoted by Lmax, it is theoretically understood that resonance at 16 kHz will not occur as long as the length Lmax is 5 mm or less. According to the first embodiment, as described above, since the sound path structure 30 is fabricated so as not to have a straight path having a length of greater than 5 mm in any direction, the length Lmax is 5 mm or less, and resonance will not occur at up to 16 kHz. In other words, according to the first embodiment, a microphone structure capable of performing acoustic sensing without causing a large resonance to occur in up to the frequency range of human hearing including 16 kHz may be fabricated.
Other advantageous effects according to the first embodiment will now be described with reference to
In the comparative example, a dimension L6 is increased by an amount equal to the size of the waterproof membrane, and as a result, the dimension L6 is significantly greater than 5 mm. Thus, in the first comparative example, it is difficult to obtain, at the position of a microphone, acoustic characteristics with which resonance will not occur in up to a high voice frequency band.
In contrast, according to the first embodiment, the first sound path 310 bends more than once so as to form the portion 310-3 as described above, so that the dimension L6 may be reduced to the dimension L4 (in other words, the dimension L6 may be split into the dimension L4 and the dimension L2). As a result, the dimension L4 may be set to 5 mm or less, and the acoustic characteristics with which resonance will not occur in up to a high voice frequency band may be obtained at the position of the microphone 14.
In the second comparative example, the waterproof membrane is disposed directly under a sound hole, and thus, a sound path structure that does not have a straight path having a length of greater than 5 mm in any direction may be fabricated. However, in the second comparative example, a frame region S2 is likely to be increased due to the waterproof membrane disposed directly under the sound hole. In other words, in the second comparative example, the above-mentioned sound path structure may be fabricated, but on the other hand the frame region S2 is likely to be increased by an amount equal to the size of the waterproof membrane. In addition, there is a case where a waterproof packing member (see
In recent years, the models of smartphones and tablet terminals each having a screen that is wide with respect to its device size have become popular. A screen having a large size provides view ability, but on the other hand there is a tendency to dislike carrying a large screen whose size has become large due to an extra frame. There is a product on the market whose frame has been partially removed by using a curved display.
Regarding this, according to the first embodiment, the size of a frame region S1 may be reduced by bending the first sound path 310 positioned directly under the sound hole 110. As a result, for example, a dimension of the frame region S1 for forming the sound hole 110 may be minimized, and the degree of freedom in design may be increased. In addition, even in the case where a waterproof packing member is disposed directly under the sound hole 110, both reducing the size of the frame region S1 and disposing the waterproof packing member directly under the sound hole 110 may be easily achieved by bending the first sound path 310 positioned directly under the sound hole 110 (see
According to the first embodiment, the sound path structure 30 bends more than once in a plane including the Z-axis (that is, the sound path structure 30 does not bend in a horizontal plane). Consequently, even in a case where the microphone 14 is disposed at a position far from the outer surface on the side on which the display unit 12 is present (a position spaced apart from the outer surface toward the Z1 side), the sound path structure 30 that does not have a straight path having a length of greater than 5 mm in any direction may be easily fabricated. For example, even in a case where the microphone 14 is disposed at a position spaced apart from the sound hole 110 by 5 mm or more in the Z direction, the sound path structure 30 that does not have a straight path having a length of greater than 5 mm in any direction may be easily fabricated.
Note that, although not illustrated, in a case where a sound hole is formed in a side surface or a rear surface of a housing, both a sound path structure with less acoustic resonance may be fabricated while a frame is made narrow. However, since the sound hole is not located on a display (screen) side, a problem occurs in that, for example, the sensitivity of acoustic sensing in an operating state decreases. Regarding this, according to the first embodiment, since the sound hole 110 is formed in the outer surface of the housing 10 on the side on which the display unit 12 is present, the probability of the occurrence of the above problem may be reduced. However, in a modification, the sound hole 110 may be formed in a side surface or a rear surface of the housing 10. For example, in the case where the sound hole 110 is formed in a side surface of the housing 10, the sound path structure 30 illustrated in
As a more specific implementation example, an electronic device 1A according to a second embodiment will now be described with reference to
The electronic device 1A has the sound hole 110 formed between an edge 121 of an outer surface of a housing 10A, the outer surface being located on the side on which the display unit 12 is present, and a glass plate 13.
The housing 10A is formed of a plurality of housing members including housing members 101, 102, and 103 and the like. A waterproof packing member 90 is disposed between the housing member 101 and the housing member 103. As illustrated in
The sound path structure 30A includes a first sound path 310A, a second sound path 320A, and a third sound path 330.
The first sound path 310A extends from the position P1 of the sound hole 110, which is formed in the outer surface of the housing 10A, to the inner position P2 in the housing 10A by bending more than once. In the example illustrated in
The second sound path 320A is connected to the first sound path 310A at the inner position P2. The second sound path 320A extends in the Z direction. A first end (an end on the Z2 side) of the second sound path 320A is connected to the first sound path 310A at the inner position P2.
The third sound path 330 extends from the end of the second sound path 320A on the Z2 side to the position of the microphone 14. A hole formed in a substrate 70 forms the third sound path 330. The microphone 14 is disposed on the substrate 70 on the Z1 side.
Note that the substrate 70 extends behind the liquid crystal panel unit 12b (on the Z1 side). In addition, a processing device (not illustrated) that processes a voice signal generated by the microphone 14 is mounted on the substrate 70. The processing device may be provided with a recognition engine that performs, for example, voice recognition, environment recognition, or the like.
An outer peripheral portion of the waterproof membrane 40 on the Z2 side is, for example, bonded to the housing member 101 and the housing member 102. In addition, an outer peripheral portion of the waterproof membrane 40 on the Z1 side is brought into contact with the substrate 70 with, for example, a rubber member interposed therebetween.
Similar to the above-described sound path structure 30, the sound path structure 30A is fabricated so as not to have a straight path having a length of greater than 5 mm in any direction. As a result of the sound path structure 30A being fabricated in this manner, resonance will not occur at up to 16 kHz.
Here, in the example illustrated in
As depicted by the characteristic C1 in
In contrast, as depicted by the characteristic C2 in
Although the embodiments have been described in detail above, the present disclosure is not limited to specific embodiments, and various modifications and changes may be made within the scope of the claims. In addition, all or some of the components according to the above-described embodiments may be combined with one another.
For example, in the above-described embodiments, although a reference value is 5 mm because the above-described embodiments are targeted on a structure with which resonance will not occur at up to 16 kHz, the reference value may be a different value. The target may be a structure with which resonance will not occur at up to 14 kHz or a structure with which resonance will not occur at up to 13 kHz or 12 kHz. For example, a value of less than 6.1 mm is preferable in order not to cause resonance at 14 kHz, and an appropriate value is, for example, 5.5 mm or less considering variations in the sound speed depending on temperature, the accuracy with which a structure is fabricated, and the like. In other words, a sound path structure that does not have a straight path having a length of greater than 5.5 mm in any direction may be fabricated in order to fabricate a structure with which resonance will not occur at up to 14 kHz.
All examples and conditional language recited herein are intended for pedagogical purposes to aid the reader in understanding the invention and the concepts contributed by the inventor to furthering the art, and are to be construed as being without limitation to such specifically recited examples and conditions, nor does the organization of such examples in the specification relate to a showing of the superiority and inferiority of the invention. Although the embodiments of the present invention have been described in detail, it should be understood that the various changes, substitutions, and alterations could be made hereto without departing from the spirit and scope of the invention.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2017-018921 | Feb 2017 | JP | national |
