Patent Publication Number: US-2010111346-A1

Title: Electronic device incorporating sound receiving member and method of manufacturing the same

Description:
BACKGROUND 
     1. Technical Field 
     The disclosure relates to electronic devices, and particularly to an electronic device incorporating a sound receiving member having sound directivity and a method for manufacturing the electronic device. 
     2. Description of Related Art 
     With the continuing development of technology, electronic devices incorporating sound receiving members, such as microphones, are widely used. The microphone is often an acoustic-to-electric transducer or sensor that converts sound into an electrical signal. Every microphone has a property known as directionality, referring to the microphone&#39;s receptivity to sound from various directions. 
     Unidirectional microphones, receptive to sounds from only one direction, are very versatile microphones, ideal for general use. Specifically, a sound receiving member of the unidirectional microphone has higher receptivity in one direction than others. Increased receptivity in the predetermined direction improves clarity of a received electrical signal. Thus, it is important to improve receptivity. 
     What is needed, therefore, is an electronic device having a sound receiving member which can overcome the described limitations. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Many aspects of the present electronic device can be better understood with reference to the following drawings. The components in the drawings are not necessarily drawn to scale, the emphasis instead being placed upon clearly illustrating the principles of the disclosed electronic device. Moreover, in the drawings, like reference numerals designate corresponding parts throughout the several views. 
         FIG. 1  is a schematic view showing properties of an ellipse. 
         FIG. 2  is an isometric view of an electronic device in accordance with the disclosure. 
         FIG. 3  is an enlarged view showing a sound receiving member of the electronic device of  FIG. 2 . 
         FIG. 4  is a cross-section of the electronic device of  FIG. 2 , taken along line IV-IV, showing an operating principle of the electronic device. 
         FIG. 5  is an enlarged view of a circle portion V of the electronic device of  FIG. 4 . 
         FIGS. 6 to 8  are schematic views showing a method for manufacturing the sound receiving member of the electronic device of  FIG. 2 . 
     
    
    
     DETAILED DESCRIPTION 
       FIG. 1  illuminates properties of an ellipse. The ellipse defines two foci F 1 , F 2 . It is known that waves, such as light or sound, from one focus F 1  (F 2 ) are reflected by the ellipse, and then pass through the other focus F 2  (F 1 ). 
     Referring to  FIGS. 2 and 3 , an electronic device in accordance with the disclosure is shown. The electronic device can be a video meeting system, mobile phone or other. In this embodiment, the electronic device is a notebook computer  10 . The notebook computer  10  includes a main body  11  and a cover  12  hinging on the main body  11  at a rear side thereof. The main body  11  is provided with a keyboard (not shown) accepting input. The cover  12  displays image and video corresponding to the input. 
     The main body  11  defines a sound receiving chamber  111  therein at a middle of a front side of a top face thereof. The sound receiving chamber  111  is surrounded by an arcuate side surface  1111  which is part of an outer elliptical surface. The elliptical surface has a first focus A 1  and a second focus A 2 . The first focus A 1  is located in the sound receiving chamber  111 , and the second focus A 2  is located beyond and above the notebook computer  10 . A line defined by the foci A 1 , A 2  is slantwise angled to the top face of the main body  11 . A microphone  113  is accommodated in the sound receiving chamber  111 . The microphone  113  and the arcuate side surface  1111  defining the sound receiving chamber  111  cooperatively form a sound receiving member of the notebook computer  10 . The microphone  113  is fixed on the main body  11  via a pair of arms  114 . The arms  114  are also received in the sound receiving chamber  111 , and electrically connect the microphone  113  with a circuit board in the main body  11 . Referring to  FIGS. 4 and 5 , the microphone  113  is located at the first focus Al of the elliptical surface. The microphone  113  has a sound receiving surface  1131  and a sound reflecting surface  1132  opposite thereto. The sound receiving surface  1131  faces the sound receiving chamber  111 , and the sound reflecting surface  1132  is coplanar with the top surface of the main body  11 . 
     Sound from a source located at the second focus A 2  of the elliptical surface, according to the optical and acoustic properties of the ellipse illustrated in  FIG. 1 , is reflected by the side surface  1111  of the sound receiving chamber  111 , and then passes the focus A 1  of the elliptical surface, namely the location of the microphone  113 . Since the sound receiving surface  1131  of the microphone  113  faces the sound receiving chamber  111 , the sound reflected by the side surface  1111  of the sound receiving chamber  111  is all received by the microphone  113 . Meanwhile, the microphone  113  has high receptivity with respect to the sound from the sound source at the focus A 2  of the elliptical surface, whereby surrounding cacophony from other positions cannot easily interfere with the desired sound from the focus A 2  of the elliptical surface. Thus, quality of the sound received by the electronic device is improved. 
       FIGS. 6 to 8  show a method of manufacturing an electronic device. 
     Referring to  FIG. 6 , a typical notebook computer  20  is provided. The notebook computer  20  includes a main body  21  and a cover  22  hinging on the main body  21  at a rear side thereof. The main body  21  defines a sound receiving location S thereon. A sound source location M, such as a user, is defined beyond and above the notebook computer  20 . The notebook computer  20  receives sound from the sound source location M at the sound receiving location S. According to a criterion of ISO 3744, perpendicular and horizontal distances between a bottom end of a front flange of the main body  21  and an ear of a user are preferably  45 cm and  25 cm, respectively. Generally a perpendicular distance and a horizontal distance between the ear and the sound source location M are respectively 5.5 cm and 4 cm. A horizontal distance between the sound receiving location S and the front flange of the main body  21  is 1 cm. Thickness of the main body  21  is 2 cm. Accordingly, a perpendicular distance and a horizontal distance between the sound receiving location S and the sound source location M are respectively 37.5 cm and 22 cm. 
     Referring to  FIG. 7 , the sound receiving and sound source locations S, M act as two foci forming an elliptical surface  25 , with a part of the elliptical surface  25  extending into the main body  21 . 
     Referring to  FIG. 8 , a space occupied by part of the elliptical surface  25  extends into the main body  21  to define a sound receiving chamber  211 . A microphone  113  illustrated in  FIG. 3  is disposed at the sound receiving location S, and a pair of arms  114  illustrated in  FIG. 3  connect the microphone  113  with the main body  21 . Thus, an electronic device having the sound receiving member in accordance with the disclosure is formed. 
     Alternatively, in the method of manufacturing the electronic device, corresponding to varying user dimensions, the perpendicular and horizontal distances between the location of the ear and the sound source location M, the horizontal distance between the sound receiving location S and the front flange of the main body  21 , and the thickness of the main body  21  can support position variation from −1 to 1 cm. Accordingly, the perpendicular distance between the location S and the location M can be in a range of from 35.5 to 39.5 cm, and the horizontal distance between the location S and the location M can be from 20 to 24 cm. 
     It is believed that the disclosure and its advantages will be understood from the foregoing description, and it will be apparent that various changes may be made thereto without departing from the spirit and scope of the disclosure or sacrificing all of its material advantages, the examples hereinbefore described merely being preferred or exemplary embodiments of the disclosure.