Patent Publication Number: US-2004042629-A1

Title: Automatic earpiece sensing

Description:
FIELD OF THE INVENTION  
       [0001] This invention relates generally to audio listening devices and more specifically to audio earpieces for stereo.  
       BACKGROUND OF THE INVENTION  
       [0002] Headphones and headsets come in a variety of form factors and can be wired or wireless. Headphones are typically listen-only devices having two earpieces that couple to a user&#39;s ears. Headsets are generally thought of as both listening and transmitting devices because they typically include a microphone along with one or two earpieces. Both headphones and headsets require two earpieces for stereo reception. Stereo headsets and headphones allow for the reception of simultaneous audio channels. For each earpiece to play back the proper channel, however, each earpiece must be placed in the appropriate ear. When used in a stereo environment, if the two earpieces have the same form factor then left and right ear designators must be marked so as to provide optimized stereo reception to the user. Thus, the user is burdened with having to position each earpiece on the correct ear by reading left and right labels on the headphone or headset.  
       [0003]FIG. 1 shows a set of prior art headphones  100  consisting of a pair of wrap around wired earpieces  102 ,  104 . In this case, each earpiece fits only one ear using two separate form factors. This burdens the manufacturer with having to design separate form factors (one form factor for each ear) and to make sure that each shipment includes the two different form factors. A shipment error of two similar form factors would prevent the user from being able to wear the product.  
       [0004] Accordingly, it would be desirable to have an improved earpiece device that could be used for stereo reception in headphones and headsets. 
     
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
     [0005] The present invention is illustrated by way of example and not limitation in the accompanying figures, in which like references indicate similar elements, and in which:  
     [0006]FIG. 1 is an example of a set of prior art headphones in accordance with the prior art;  
     [0007]FIG. 2 is an integrated microphone/receiver system in accordance with the prior art;  
     [0008]FIG. 3 is a partially exploded view of an earpiece formed in accordance with the preferred embodiment of the invention;  
     [0009]FIGS. 4 and 5 show a headphone device formed in accordance with the preferred embodiment coupled to a user&#39;s ears;  
     [0010]FIG. 6 is a set of headphones indicating first and second orientations in accordance with the present invention; and  
     [0011]FIG. 7 is the set headphones of FIG. 6 with the earpieces interchanged in accordance with the present invention. 
    
    
     [0012] Skilled artisans will appreciate that elements in the figures are illustrated for simplicity and clarity and have not necessarily been drawn to scale. For example, the dimensions of some of the elements in the figures may be exaggerated relative to other elements to help to improve understanding of embodiments of the present invention.  
     DETAILED DESCRIPTION OF THE DRAWINGS  
     [0013] The apparatus to be described herein provides an earpiece device with automatic left/right location sensing capability, enabling two such devices to provide stereo reception with minimal user adjustment. In accordance with the present invention, interchangeable earpieces provide different angles of rotation when coupled to different ears and are thus capable of being used in either ear. An existing earpiece, known in the art, will initially be described and then an example given of how this earpiece can be modified and adapted into a stereo headphone system. While the preferred embodiment describes a preferred earpiece form factor, those skilled in the art will recognize that the concept can be extended to a variety of earpiece form factors.  
     [0014] Integrated microphone/receiver systems exist in a variety of form factors many of which can be worn about the ear as a single earpiece. Referring to FIG. 2, there is shown a prior art integrated microphone/receiver system manufactured by Motorola, Inc. System  200  is a hooked shaped earpiece device having a form factor to fit around the typical human ear. A main portion  210  houses device electronics (not shown) that receive and process audio signals along with a microphone  204 . A tubular portion  202  extends from the main portion  210  and curves in a hook like manner for fitting around the top and front portions of the ear. The tubular portion  202  has a terminal end  206  that functions as a receptacle or tube mount for an attached sound delivery tube  208 . The sound delivery tube  208  is pivotable about the terminal end  206  to accommodate left and right ear use, and angular corrections to match a user&#39;s ear canal access. The rotation angle of the sound delivery tube  208  is thus different for the left or right ear.  
     [0015] Devices like those shown in FIG. 2 enable the wearer to hear and be heard clearly and are often used by firefighters, police, and factory workers to facilitate hearing under adverse conditions, such as transportation and construction environments. These devices are typically coupled through a conductive cable  212  to the user&#39;s radio, such as a two-way radio. In accordance with the preferred embodiment of the invention to be described next, the form factor of the earpiece device described above is modified and provided as two earpieces adapted for use as stereo headphones.  
     [0016]FIG. 3 shows a partially exploded view of an earpiece device in accordance with the preferred embodiment of the invention. Like assembly  200 , assembly  300  includes a main portion  302  for housing electronics (not shown) for processing audio signals. Assembly  300  further includes a tubular portion  304  having a terminal end  306  that functions as a receptacle or tube mount for an attached sound delivery tube  308 . In accordance with the preferred embodiment of the invention, the terminal end  306  includes first and second conductive wires  310 ,  312 , and the sound delivery tube  308  includes a conductive liner  314 . The conductive liner  314  is situated such that, when assembled, the conductive wires  310 ,  312  are either shorted together or open circuited depending on the rotation of the sound delivery tube  308 . In accordance with the preferred embodiment, open or short-circuiting of the conductive wires  310 ,  312  is used as an indicator as to the left or right orientation of the earpiece device. A variety of other approaches, some of which will be described later, can be used to provide the orientation information as well.  
     [0017] Alternative form factors other than that shown in FIG. 3 can also be used. For example, the sound delivery tube  308  could be eliminated and replaced with a pivotable ear bud form factor. The different angles of rotation provided by the pivotable aspect of the device allows for automatic left/right ear sensing. An earpiece can thus receive left or right audio channels, making two such devices interchangeable. Depending on which ear each earpiece is coupled, a communication device can respond and always provide left and right audio channels simultaneously to the left and right ears. A microphone could also be added to one or more earpieces if desired for headset transmit capability.  
     [0018] Referring now to FIGS. 4 and 5, two earpieces formed in accordance with the preferred embodiment of the invention provide stereo headphones for a user (shown in phantom). Earpiece  402  is coupled to the user&#39;s left ear while earpiece  404  is coupled to the user&#39;s right ear. In accordance with the present invention, each earpiece  402 ,  404  provides orientation information such that a communication device  400 , such as a radio or other audio source device, automatically senses to which ear each of the first and second earpieces is coupled. The different angles of orientation provide indicators, such as a short on one side and an open on the other side, for automatic left/right sensing.  
     [0019] Referring now to FIGS. 6 and 7 there is shown a headphone device  600  formed in accordance with the preferred embodiment and worn in a face forward view. Headphone device  600  includes earpieces formed in accordance with the preferred embodiment. The headphone device  600  includes a first earpiece  602  for coupling to a user&#39;s ear, and a second earpiece  604  for coupling to the user&#39;s other ear. In accordance with the present invention, each earpiece  602 ,  604  provides orientation information such that a communication device, such as a radio, automatically senses to which ear each of the first and second earpieces is coupled. First earpiece  602  and second earpiece  604  provide first and second orientations  606 ,  608  when coupled to the user&#39;s ears.  
     [0020] The first earpiece  602  includes electronics for processing audio signals housed in main portion  610 , and a terminal end (not shown, but previously described) leads into sound delivery tube  614 . The second earpiece  604  likewise includes electronics for processing audio signals housed in a main portion  616 , and a terminal end (not shown, but previously described) leading to a sound delivery tube  620 . In accordance with the preferred embodiment, each earpiece  602 ,  604  includes two conductors on each terminal end (not shown, but previously described). Also in accordance with the preferred embodiment, each sound delivery tube  614 ,  620  includes a conductive liner (not shown, but previously described) coating a portion of the tube&#39;s inner surface. The sound delivery tube  614  is inserted into either ear with a first angle of rotation  606  as shown in FIG. 6. The second delivery tube  620  is inserted into the other ear with a second angle of rotation  608  different from the first as indicated in FIG. 6. In this example, it will be assumed that the first angle of rotation  606  provides an open circuit between the conductors while the second angle of rotation  608  shorts the conductors together. As mentioned above, the conductors being shorted together indicates either a left or right ear orientation. The conductors being open-circuited indicates the opposite ear orientation. The open/short indication is received by the earpiece electronics and used as an indicator for a communication device to orient a stereo signal properly to each ear.  
     [0021]FIG. 7 shows the headphone device  600  with the earpieces  602 ,  604  interchanged in accordance with the present invention. Again, system  600  includes first and second earpiece  602  and  604 , however the earpieces have now been inserted into opposite ears. The orientation of each sound delivery tube  614 ,  620  is rotated to accommodate insertion into the opposite ear. The second earpiece  604  now has the first orientation  606  while the first earpiece  602  has the second orientation  608 . In this orientation the two conductors on the terminal end of tube  620  are open-circuited for orientation  606  while the conductors on the terminal end of sound delivery tube  614  are short-circuited to provide orientation  608 .  
     [0022] As mentioned above, the conductors being shorted together indicates either a left or right ear orientation. The conductors being open-circuited indicates the opposite ear orientation. Accordingly, if the first earpiece orientation generates a short-circuit indicator at the right ear, then the second earpiece orientation will indicate an open-circuit on the left ear. When the earpieces are swapped, the first earpiece orientation will indicate an open-circuit on the left ear, and the second earpiece will indicate a short circuit on the right ear. The ability to sense left and right orientation allows the audio source to provide a stereo signal to the appropriate ears. The headphone device  600  can be used to receive audio signals from a variety of communication sources including but not limited to radios, cellular phones, CD players, and televisions to name a few.  
     [0023] While the preferred embodiment has been discussed in terms of a “short circuit” approach to providing orientation information, a variety of other techniques can be used as well. For example, a micro-switch and mechanical pit implementation can also be used. In this type of implementation, as the eartube is rotated, the micro-switch falls in the pit and opens/closes the contact. A mechanical approach can also be used to achieve similar results by using two transducers emanating the audio along with the rotation of the eartubes to direct the appropriate transducer to each ear. Thus, a variety of approaches can be taken to provide the orientation information.  
     [0024] While the headphones of the present invention have thus been described in terms of left/right stereo audio pair transmissions, the two audio channels need not be limited to this specific application. Since the two audio channels are separate and distinct, the signals provided to these channels can also be distinct and unrelated signals. Using the notation of Channel A and Channel B, instead of left/right, Channel A can use a first orientation and Channel B can use a second orientation as previously described. The following provides examples of distinct channels:  
     [0025] For use with a television: Channel A=Primary program audio, Channel B=SAP (secondary audio program, an alternate language track for instance).  
     [0026] For use with a television: Channel A=Main picture audio, Channel B=PIP (picture in picture) channel audio.  
     [0027] For use as a museum audio tour guide: Channel A=main narration, Channel B=alternate language, or perhaps a more detailed, or more technical, program for the advanced listener.  
     [0028] For use with a DVD player: Channel A=Main audio, Channel B=commentary track.  
     [0029] Orientation information has been described thus far as originating from the earpiece, and the communication device making a routing decision based on that information. In another alternative embodiment, the communication device (such as communication device  400  in FIG. 4) can broadcast both channels to both left and right devices. The earpiece devices themselves select which channel goes to which earpiece, for example through the use of internal control circuitry. This alternative embodiment makes many applications, like the “audio tour guide” discussed above quite simple to implement.  
     [0030] Those skilled in the art will recognize that the above examples represent only a few of the possible channel combinations that might be useful to users. Since the two distinct channels each have a distinct orientation associated with them, there is no need to label the devices and the devices are interchangeable.  
     [0031] With the advancements in wireless technology, such as Bluetooth technology, many wireless systems are beginning to emerge in the marketplace. Wireless earpieces and headsets provide users with extra mobility. Bluetooth technology can provide three audio channels simultaneously thus allowing for stereo capability in a wireless environment as well as independent channels. Headphones formed in accordance with the present invention can take advantage of this capability without the problems of orientation previously discussed.  
     [0032] Accordingly there has been provided a headphone device comprising first and second earpieces having automatic left/right ear sensing for stereo as well as the ability to receive two separate and distinct audio channels. The headphones can be wired or wirelessly coupled to a communication device. The interchangeability of the earpieces of the present invention eases the burden on the manufacturer because a single form factor can be used for both pieces. Minimal effort is required by the user because the need to read orientation labels is eliminated. Each earpiece provides appropriate orientation in either ear, thus providing an improved earpiece device.  
     [0033] In the foregoing specification, the invention has been described with reference to specific embodiments. However, one of ordinary skill in the art appreciates that various modifications and changes can be made without departing from the scope of the present invention as set forth in the claims below. Accordingly, the specification and figures are to be regarded in an illustrative rather than a restrictive sense, and all such modifications are intended to be included within the scope of present invention.  
     [0034] Benefits, other advantages, and solutions to problems have been described above with regard to specific embodiments. However, the benefits, advantages, solutions to problems, and any element(s) that may cause any benefit, advantage, or solution to occur or become more pronounced are not to be construed as a critical, required, or essential features or elements of any or all the claims. As used herein, the terms “comprises,” “comprising,” or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus.