Patent Publication Number: US-9426593-B2

Title: Assisting listening device having audiometry function

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This patent application is a continuation-in-part of U.S. patent application Ser. No. 13/362,403 filed Jan. 31, 2012 entitled “ASSISTING LISTENING DEVICE HAVING AUDIOMETRY FUNCTION”, the entire disclosure of which is incorporated herein by reference. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention The present invention relates to assisting listening device technology and more particularly, to an assisting listening device having audiometry function. 
     2. Description of the Related Art 
     The so-called assisting listening device is to pick up external sound by a microphone, and then to filter noises or adjust the ambient sound by a digital signal processor (DSP), and then to output filtered sound through a speaker toward the user&#39;s eardrum. Thus, any person having a different hearing loss level can join community life easily, improving living quality and maintaining good human relations. 
     However, even persons with hearing loss wearing an assisting listening device, the hearing condition may deteriorate as grow in age. Conventional assisting listening device designs do not provide any audiometry function. If the user cannot adjust the settings of the assisting listening device subject to the user&#39;s hearing loss level, the assisting listening device will be unable to process the picked up external sound optimally, affecting the assisting listening effect of the assisting listening device and causing trouble for the user. 
     Further, after setting of hearing threshold curve subject to a particular hearing-impaired user, the assisting listening device can simply be used by this hearing-impaired user, not suitable for any other person suffering a different condition of hearing loss. Thus, the application of conventional assisting listening device is limited, lacking in popularity. 
     SUMMARY OF THE INVENTION 
     The present invention has been accomplished under the circumstances in view. It is the main object of the present invention to provide an assisting listening device having audiometry function, which allows adjustment subject the hearing level of different users or a user&#39;s different hearing conditions, providing excellent effects of assisting listening. 
     To achieve this and other objects of the present invention, an assisting listening device comprises an earphone, a testing signal generator, a feedback generator, and a control box. The earphone comprises a microphone for picking up external sound and generating a corresponding acoustic signal, an acoustic signal processor electrically coupled to the microphone for receiving and processing the acoustic signal, and a speaker electrically coupled to the audio signal processor for receiving the processed acoustic signal and emitting corresponding sound. The testing signal generator is electrically connected to the speaker of the earphone, and adapted to generate a testing signal and transmit the testing signal to speaker. The testing signal generator is disposed outside the earphone. The feedback generator is adapted to generate a feedback signal subject to the testing signal from the testing signal generator. The control box comprises a digital signal processor electrically connected to the acoustic signal processor of the earphone, the test testing signal generator and the feedback generator. 
     The assisting listening device is switchable between an audiometry mode for evaluating a hearing threshold level of a user, and an assisting listening mode when the speaker emits the sound corresponding to the acoustic signal that is processed subject to the hearing threshold level of the user. 
     Further, the feedback generator can be a pushbutton electrically connected to the digital signal processor. When hearing the testing signal generated by the testing signal generator, the user can press the pushbutton to provide the feedback signal to the digital signal processor. 
     Further, the feedback generator can be a microphone electrically connected to the acoustic signal processor of the earphone. When the testing signal from the testing signal generator reaches the user&#39;s eardrum, the microphone picks up the sound from the eardrum and converts it into a feedback signal, and then transmits this feedback signal through the acoustic signal processor to the digital signal processor of the control box for reading. 
     Other advantages and features of the present invention will be fully understood by reference to the following specification in conjunction with the accompanying drawings, in which like reference signs denote like components of structure. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a block diagram of an assisting listening device in accordance with a first embodiment of the present invention. 
         FIG. 2  is a block diagram of an assisting listening device in accordance with a second embodiment of the present invention. 
         FIG. 3  is a block diagram of an assisting listening device in accordance with a third embodiment of the present invention. 
         FIG. 4  is a preferable overall working flowchart of an assisting listening device of the present invention. 
         FIG. 5  is a preferable working flowchart of an assisting listening device of the present invention, in which the assisting listening device is in the audiometry mode. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Referring to  FIG. 1 , an assisting listening device  10  in accordance with a first embodiment of the present invention is shown. The assisting listening device  10  is either manually or automatically switchable between an audiometry mode and an assisting listening mode. The assisting listening device  10  comprises an earphone  20 , a testing signal generator  30 , a feedback generator  32 , and a control box  40 . The assisting listening device  10  provides active audiometry function. 
     The earphone  20  comprises a microphone  22 , an acoustic signal processor (ASP)  24  electrically coupled to the microphone  22 , and a speaker  26  electrically coupled to the audio signal processor  24 . The earphone  20  picks up external sound by the microphone  22  and converts picked up sound into an acoustic signal, which is then processed by the acoustic signal processor  24  and then transmitted by the acoustic signal processor  24  to the speaker  26 , causing the speaker  26  to emit corresponding sound toward the user&#39;s eardrum. The testing signal generator  30  is electrically connected to the speaker  26  of the earphone  20 , and adapted to generate a testing signal and transmit the testing signal to the speaker  26 . The testing signal can be a pure tone, warble tone or narrow band noise at 500 Hz, 1000 Hz, 2000 Hz or 4000 Hz. 
     The feedback generator  32  in this embodiment is a pushbutton pressable by an external pressure to generate a feedback signal. In other possible embodiments of the present invention, the feedback generator  32  can also be integrated in the earphone  20  or the display device  50 . 
     The control box  40  comprises a digital signal processor (DSP)  42 , which is electrically coupled with the acoustic signal processor  24  of the earphone  20 , the testing signal generator  30  and the feedback generator  32  for controlling the testing signal generator  30  to generate a testing signal and receiving and storing the feedback signal from the feedback generator  32  for evaluating the user&#39;s hearing condition. Further, the digital signal processor (DSP)  42  and the feedback generator  32  can be integrated in the control box  40 . 
     Further, the assisting listening device  10  provides a display device  50  electrically connected to the control box  40 , facilitating the user to see the audiometry result and to adjust the function of the control box  40 . 
     Further, the aforesaid display device  50  can be disposed in a mobile phone, computer or TV. Further, electrical connection between the earphone  20 /control box  40  and the display device  50  can be done by a cable or in a wireless manner. 
       FIG. 2  illustrates an assisting listening device  60  in accordance with a second embodiment of the present invention. This assisting listening device  60  provides a function of passive audiometry, comprising an earphone  70 , a testing signal generator  80 , and a control box  90 . The earphone  70  of this second embodiment is structurally similar to that of the aforesaid first embodiment. 
     The testing signal generated by the testing signal generator  80  can be narrow band noise, tone burst or distortion product pure tone at 500 Hz, 1000 Hz, 2000 Hz or 4000 Hz. 
     The feedback generator  82  in this second embodiment is a microphone or a sensor integrated in the earphone  70  and electrically connected to the acoustic signal processor  74  of the earphone  70 . 
     When the assisting listening device  60  is switched to the audiometry mode by using the control box  90 , the testing signal generator  80  will be controlled by the digital signal processor  92  to generate a testing signal. When the testing signal is transmitted from the testing signal generator  80  through the speaker  76  to the user&#39;s eardrum, the feedback generator  82 , which is a microphone in this second embodiment, will automatically pick up the sound from the vibration of the eardrum and convert it into a feedback signal, and then transmit this feedback signal through the acoustic signal processor  74  to the digital signal processor  92  of the control box  90  for determining the hearing threshold level. 
     Similarly, the digital signal processor  92  of the control box  90  can be electrically connected to a display device  50  to provide the same effects as the aforesaid first embodiment. 
     Further, the feedback generator  82  can also be used for background noise correction. When the user is in a noisy environment, the assisting listening device can use the feedback generator  82  to pick up sound from the ear canal and then remove the unnecessary noises for determining the user&#39;s hearing level accurately. 
       FIG. 3  illustrates an assisting listening device  100  in accordance with a third embodiment of the present invention. The assisting listening device  100 , likewise, includes an earphone  110 , a control box  120 , a test signal generator  130  integrated in the acoustic signal processor  114  of the earphone  110 , a feedback signal generator  140  integrated in the earphone  110 , and a display device  150  such as a mobile phone. The earphone  110  in this third embodiment is structurally identical to that in the second embodiment. On the other hand, the control box  120  includes a digital signal processor  122  and is functionally integrated in the display device  150 , which is further integrated with a user interface  152  for switching the assisting listening device  100  between the audiometry mode and the assisting listening mode. The user interface  152  can be realized in the form of, for example, a touch panel that functions as a switch in the present embodiment. In other possible embodiments of the present invention, however, a switch can also be alternatively provided on the earphone, the control box or the display device for the user to manually switch the modes of the assisting listening device. In some other possible embodiments that the switching of modes is automatically done by the control box, a physical switch is not necessarily provided on the assisting listening device. 
     Referring to  FIGS. 1 and 4 . When the assisting listening device  10  is switched to the audiometry mode, the digital signal processor  42  transmits a control signal to the testing signal generator  30 . At this time, the testing signal generated by the testing signal generator  30  will be transmitted through the speaker  26  of the earphone  20  toward the user&#39;s eardrum. A feedback signal can be either manually generated or automatically generated by the feedback generator  32  and transmitted to the digital signal processor  42  of the control box  40 , enabling the digital signal processor  42  to determine the user&#39;s hearing level subject to the feedback signal. A preferable determination of the user&#39;s hearing level is to pick up the most suitable one from the various hearing threshold curves defined subject to the user&#39;s hearing condition, and then a test result determined by the digital signal processor  42  is stored in the acoustic signal processor  24  as the third step in  FIG. 4 . Alternatively, the test result determined by the digital signal processor  42  can be stored right in the digital signal processor  42  itself in other possible embodiments of the present invention. 
     More specifically, a flowchart of a preferable determination of the user&#39;s hearing level is shown in  FIG. 5 . When the determination starts, the digital signal processor  42  will set an initial value of Count to 0 and a dB value of the testing signal to a start value, e.g. 0. Then the digital signal processor  42  will send the testing signal at that specific dB value to the speaker  26  via the testing signal generator  30 . If the digital signal processor  42  receives a feedback signal manually or automatically generated by the feedback generator  32 , the digital signal processor  42  will add 1 to Count and determine if Count is already 2. If not, the digital signal processor  42  will reduce the dB value of the testing signal by x dB where x is preferably between 1-20 and more preferably 10 in a preferred embodiment. The digital signal processor  42  then resends the testing signal with reduced dB value and test again. On the other hand, if the digital signal processor  42  does not receive the response signal, which implies that the user is unable to hear the testing signal at that specific dB value, the digital signal processor  42  will increase the dB value of the testing signal by y where y is preferably between 1-20 and more preferably smaller than x, e.g. y is 5 in the preferred embodiment, and then resend the testing signal. Repeat the test until the number of Count is 2. When the test is completed, a threshold of the user&#39;s hearing level is set to be the final dB value of the testing signal and the test result is stored in the acoustic signal processor  24  or the digital signal processor  42 . 
     Referring to the fourth and the fifth steps in  FIG. 4 . When the assisting listening device  10  is switched, either manually or automatically after the afore-mentioned test is finished, to the assisting listening mode, the microphone  22  of the earphone  20  picks up external sound and converts it into an acoustic signal processor  24 , and then the acoustic signal processor  24  filters noises from the acoustic signal and then adjusts the acoustic signal subject to the test result. For example, if the threshold value determined in the audiometry mode is 3 dB higher than a predetermined value, the acoustic signal generates by the microphone  22  is compensated with 3 dB by the acoustic signal processor  24 . The compensated acoustic signal is then transmitted to the speaker  26 , causing the speaker  26  to emit corresponding sound at the compensated dB value toward the user&#39;s eardrum, and thus, the user can hear the sound smoothly. In some possible embodiments that the test result is stored in the digital signal processor  42  rather than in the acoustic signal processor  24 , the acoustic signal processor  24  will further read the test result from the digital signal processor  42  before compensating the acoustic signal transmitted from the microphone  22 . 
     In conclusion, the assisting listening device of the present invention provides an audiometry function for enabling the user to know his (her) hearing level. Further, the audiometry mode has two different designs. A user can adjust the functioning of the assisting listening device subject to the audiometry result. Or, the digital signal processor of the assisting listening device can automatically adjust the best operating mode subject to the audiometry result to fit different users suffering different degrees of hearing loss, enabling every user to hear sound comfortably and achieving excellent effects of assisting listening. 
     Although particular embodiments of the invention have been described in detail for purposes of illustration, various modifications and enhancements may be made without departing from the spirit and scope of the invention. Accordingly, the invention is not to be limited except as by the appended claims.