Abstract:
A communication device is disclosed herein. In an example embodiment, a communication device includes an aperture section configured to attach to a protruding section of another communication device magnetically, and a first wireless communicator configured to wirelessly communicate with a second wireless communicator of the another communication device at a frequency associated with a millimeter-wave band, the first wireless communicator including at least one transmitting coupler, wherein the at least one transmitting coupler converts a wired signal to a radio signal.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
       [0001]    The present application claims priority to and the benefit as a continuation application of U.S. patent application Ser. No. 14/868,642, entitled, “Connector System, Connecting Cable and Receiving Tool”, filed Sep. 29, 2015, which is a continuation of U.S. patent application Ser. No. 13/889,035, entitled, “Connector System, Connecting Cable and Receiving Tool”, filed May 7, 2013, now U.S. Pat. No. 9,246,588, issued Jan. 26, 2016, which is a divisional of U.S. patent application Ser. No. 13/011,294, entitled, “Connector System, Connecting Cable and Receiving Tool”, filed Jan. 21, 2011, now U.S. Pat. No. 9,118,417, issued Aug. 25, 2015, which is a continuation of U.S. patent application Ser. No. 12/682,484, entitled, “Connector System, Connecting Cable and Receiving Tool”, filed Apr. 9, 2010, which was a National Stage of International Application No. PCT/JP2008/068244 filed on Oct. 7, 2008 and which claims priority to Japanese Patent Application No. 2007-267139, filed in the Japanese Patent Office on Oct. 12, 2007, the entire contents of each of which are incorporated herein by reference. 
     
    
     BACKGROUND 
       [0002]    The present disclosure relates to a connector system, a connecting cable and a receiving tool applicable to a connector cable connecting a video reproducer and a display. More specifically, a receiving tool provided on a device has a first wireless communication section. A connecting tool connected to the receiving tool in a freely attachable/detachable manner has a second wireless communication section at a position opposite to the first wireless communication section of the receiving tool. Thus, wireless communication can be performed in a non-contact state, and the connecting tool can be easily attached to/detached from the receiving tool without breaking a terminal due to contact such as in a case where a conventional contact type terminal is used. 
         [0003]    In recent years, owing to next-generation large capacity optical disks such as the Blue-ray Disc (Registered Trademark) and high-vision broadcasting, there are increasing cases where a high-resolution video is to be handled. In this case, an HDMI (High-Definition Multimedia Interface (Registered Trademark)) connector  200  shown in  FIG. 1  is used to connect a disk reproduction device with a display.  FIG. 1  is a perspective view illustrating an example of the configuration of the connector  200 . The connector  200  shown in  FIG. 1  adopts a TMDS (Transition Minimized Differential Signaling (Registered Trademark)) transmission method. The TMDS (Registered Trademark) transmission method has four channels. These four channels are assigned to R, G and B (red, green and blue) video signals, one per each channel, and one channel is assigned to a signal for synchronizing a clock frequency. The connector  200  includes a terminal  40  and a copper cable  41 . The connector  200  transmits video signals through the copper cable  41  with the terminal  40  inserted into a socket of the HDMI (Registered Trademark), which is not shown. 
         [0004]      FIG. 2  is a schematic diagram illustrating an example of the configuration of the connector  200 . The terminal  40  of the connector  200  has Pin  1  to Pin  19 . The Pin  1  to Pin  9  are for an RGB (red, green and blue) video signal connection. The Pin  10  to Pin  12  are for a synchronization clock frequency connection. The Pin  13  to Pin  19  are for a power supply connection, a control system connection, etc. The connector  200  electrically outputs R, G and B video signals input from the Pin  1  to Pin  9  through the copper cable  41 . 
         [0005]    In contrast to the copper cable  41 , a connector using an optical fiber in a signal transmission path has also been proposed. An optical fiber connector is broadly divided into two types: a single core type having one optical fiber and a multi-core type having a plurality of optical fibers. Single core plugs are widespread mainly for consumer use because of its easy connection and high dust tolerance. However, a data transfer rate is low due to being a single core, which may lead to a problem when high-capacity high-resolution videos are handled. 
         [0006]    On the other hand, although the connection is difficult due to being a multi-core, because a data transfer rate is high and high-capacity high-resolution videos can be handled, multi-core plugs are widespread mainly for industrial use.  FIG. 3  is a perspective view illustrating an example of the configuration of a multi-core MT connector  300 . The MT connector  300  shown in  FIG. 3  includes a plug section  47  and a connector section  48 . 
         [0007]    The plug section  47  has a plug body  42 , an optical fiber tape  43 , a guide pin  44  and an optical fiber end portion  45 . The optical fiber tape  43  extends from the rear end of the plug body  42 . Two guide pins  44  protrude from the front end of the plug body  42 . The optical fiber end portion  45  is provided on the front end of the plug body  42 . An optical signal is input to/output from the optical fiber end portion  45 . 
         [0008]    The connector section  48  has a connector body  46 , an optical fiber tape  43  and an optical fiber end portion (not shown). The optical fiber tape  43  extends from the rear end of the connector body  46 . The optical fiber end portion (not shown) is provided on the front end of the connector body  46 . An optical signal is input to/output from the optical fiber end portion. 
         [0009]    When the plug section  47  is connected with the connector section  48 , the guide pin  44  of the plug section  47  is inserted into the insertion portion (not shown) in the connector section  48 , and the plug section  47  and the connector section  48  are secured by a given fastener. At that time, the optical fiber end portion  45  of the plug section  47  is aligned with the optical fiber end portion (not shown) of the connector section  48 . Since an accuracy of the alignment of the optical fiber end portions must be 1 μm or less, a dedicated attaching/detaching tool is required (e.g., FIG. 1 in JP-A-2004-317737). 
         [0010]    According to the HDMI (Registered Trademark) connector  200  shown in  FIGS. 1 and 2 , the terminal  40  has 19 pins from Pin  1  to Pin  19 . Therefore, when the terminal  40  is inserted into a given connector, in a case where the terminal  40  is inserted accidentally slightly slanted with respect to the connector, the 19 pins may not match the insertion holes of the connector, and the pins may be bent and broken. 
         [0011]    In addition, according to the MT connector  300  shown in  FIG. 3 , since an accuracy of the alignment of the optical fiber end portion  45  of the plug section  47  with the optical fiber end portion (not shown) of the connector section  48  must be 1 μm or less, which requires a dedicated attaching/detaching tool for industrial use, employment for consumer use is difficult. 
         [0012]    Accordingly, it is desirable to provide a connector system, a connecting cable and a receiving tool allowing a connecting tool to be easily attached to/detached from a receiving tool without breaking a terminal due to contact such as in a case where a conventional contact type terminal is used. 
       SUMMARY 
       [0013]    A connector system according to an embodiment includes a receiving tool provided on a device, and a connecting tool connected to the receiving tool in a freely attachable/detachable manner so as to establish a connection between devices, the receiving tool having a first wireless communication section that performs wireless communication, the connecting tool having at a position opposite to the first wireless communication section of the receiving tool a second wireless communication section that performs wireless communication with the first wireless communication section. 
         [0014]    According to the connector system of the present embodiment, the receiving tool (connector) provided on a device has a first wireless communication section that performs wireless communication. The connecting tool (plug) connected to the receiving tool in a freely attachable/detachable manner has a second wireless communication section at a position opposite to the first wireless communication section of the receiving tool. For example, the connecting tool is inserted and fit into the receiving tool in a given direction, and the first wireless communication section and the second wireless communication section are positioned so that the given insertion direction is orthogonal to the direction normal to the output surface of a wireless signal emitted by the first and second wireless communication sections. As a result, when the connecting tool is connected to the receiving tool, the second wireless communication section of the connecting tool and the first wireless communication section of the receiving tool can wirelessly communicate with each other in a non-contact state. Thus, the connecting tool can be easily attached to/detached from the receiving tool without breaking a terminal due to contact such as in a case where a conventional contact type terminal is used. 
         [0015]    In order to solve the problems described above, a connecting cable according to the present invention includes a cable for transmitting a signal, a first connecting tool attached to one end of the cable, and a second connecting tool attached to the other end of the cable, at least one of the first and second connecting tools being connected in a freely attachable/detachable manner to a receiving tool of a device provided with the receiving tool having a first wireless communication section that performs wireless communication, and having at a position opposite to the first wireless communication section of the receiving tool a second wireless communication section that performs wireless communication with the first wireless communication section. 
         [0016]    The connecting cable according to the present embodiment is applied when establishing a connection between devices, at least one of which is provided with the receiving tool having the first wireless communication section that performs wireless communication. At least one of the first and second connecting tools of the connecting cable has a second wireless communication section at a position opposite to the first wireless communication section of the receiving tool. Thus, the second wireless communication section of the connecting tool and the first wireless communication section of the receiving tool can wirelessly communicate with each other in a non-contact state. 
         [0017]    In order to solve the problems described above, a receiving tool according to the present invention connects in a freely attachable/detachable manner to a connecting tool having a second wireless communication section that performs wireless communication, and has at a position opposite to the second wireless communication section of the connecting tool a first wireless communication section that performs wireless communication with the second wireless communication section. 
         [0018]    The receiving tool according to the present embodiment is applied to a device to which the connecting tool having the second wireless communication section that performs wireless communication is connected. The receiving tool has the first wireless communication section at a position opposite to the second wireless communication section of the connecting tool, which is connected thereto in a freely attachable/detachable manner. Thus, the first wireless communication section of the receiving tool and the second wireless communication section of the connecting tool can wirelessly communicate with each other in a non-contact state. 
         [0019]    Additional features and advantages are described herein, and will be apparent from, the following Detailed Description and the figures. 
     
    
     
       BRIEF DESCRIPTION OF THE FIGURES 
         [0020]      FIG. 1  is a perspective view illustrating an example (1) of the configuration of an HDMI (Registered Trademark) connector  200  according to a conventional example. 
           [0021]      FIG. 2  is a schematic diagram illustrating an example (2) of the configuration of the connector  200  according to the conventional example. 
           [0022]      FIG. 3  is a perspective view illustrating an example of the configuration of an MT connector  300  according to the conventional example. 
           [0023]      FIG. 4  is a perspective view illustrating an example of the configuration of an attachable/detachable connector system  100  according to an embodiment. 
           [0024]      FIG. 5  is a perspective view illustrating an example of the configuration of a plug  1 A and a connector  2 . 
           [0025]      FIG. 6A  is a perspective view illustrating an example of the beginning of fitting of the plug  1 A. 
           [0026]      FIG. 6B  is a perspective view illustrating an example of the completion of fitting of the plug  1 A. 
           [0027]      FIG. 7A  is a top view illustrating an example of the configuration of the plug  1 A. 
           [0028]      FIG. 7B  is a cross sectional view in the X 1 -X 1  arrow direction of  FIG. 7A  illustrating the example of the configuration of the plug  1 A. 
           [0029]      FIG. 8A  is a side view illustrating an example of the configuration of the plug  1 A. 
           [0030]      FIG. 8B  is a cross sectional view in the X 2 -X 2  arrow direction of  FIG. 8A  illustrating the example of the configuration of the plug  1 A. 
           [0031]      FIG. 9  is a block diagram illustrating an example of the configuration of an RF chip  5 A of the plug  1 A. 
           [0032]      FIG. 10  is a block diagram illustrating an example of the configuration of an RF chip  5 B of a plug  1 B. 
           [0033]      FIG. 11  is a block diagram illustrating an example of the configuration of an RF chip  5 C of a plug  1 C. 
           [0034]      FIG. 12  is a block diagram illustrating an example of the configuration of part of an RF chip  5 D of a plug  1 D. 
           [0035]      FIG. 13A  is a perspective view illustrating an example of a first manufacturing process of the RF chip  5 A. 
           [0036]      FIG. 13B  is a perspective view illustrating an example of a second manufacturing process of the RF chip  5 A. 
           [0037]      FIG. 14A  is a top view illustrating an example of the configuration of the connector  2 . 
           [0038]      FIG. 14B  is a cross sectional view in the X 3 -X 3  arrow direction of  FIG. 14A  illustrating the example of the configuration of the connector  2 . 
           [0039]      FIG. 15A  is a side view illustrating an example of the configuration of the connector  2 . 
           [0040]      FIG. 15B  is a cross sectional view in the X 4 -X 4  arrow direction of  FIG. 15A  illustrating the example of the configuration of the connector  2 . 
           [0041]      FIG. 16  is a block diagram illustrating an example of the configuration of an RF chip  6  and an RF circuit  52 . 
       
    
    
     DETAILED DESCRIPTION 
       [0042]    An embodiment of a connector system, a connecting cable and a receiving tool will be described below with reference to the drawings. 
         [0043]    An example of the configuration of an attachable/detachable connector system  100  will be described with reference to  FIG. 4 . The attachable/detachable connector system  100  shown in  FIG. 4  is used to connect a video reproducer such as a DVD recorder (not shown) with a video output device such as a projector  21 . 
         [0044]    The attachable/detachable connector system  100  includes a connecting cable  1  and a connector  2  (an example of a receiving tool). One end of the connecting cable  1  is fit into the connector  2  of the projector  21 , and the other end of the connecting cable  1  is fit into the connector  2  of the video reproducer. A video/audio signal reproduced by the video reproducer is output to the projector  21  through the connecting cable  1 . 
         [0045]    The connecting cable  1  includes plugs  1 A and  1 B and a combined electrical and optical cable  10 . The plug  1 A is an example of a connecting tool, and is connected to the connector  2  in a freely attachable/detachable manner. The plug  1 A includes a plug body  3 , a protruding section  7  and a cable support section  9 . The protruding section  7  is provided on the front end of the rectangular parallelepiped plug body  3 , and the cable support section  9  is provided on the rear end of the plug body  3 . A first RF (Radio Frequency) chip  5 A shown in  FIG. 5  is provided in the protruding section  7 . The protruding section  7  is inserted into an aperture section  8  in the connector  2  of the projector  21 , for example. 
         [0046]    The cable support section  9  extends and supports the combined electrical and optical cable  10  (an example of a cable). The plug  1 B is provided on the end portion of the extended combined electrical and optical cable  10 . Since the plugs  1 B and  1 A have the identical configuration, the description of the configuration of the plug  1 B is omitted. 
         [0047]    An example of the configuration of the plug  1 A and the connector  2  will be described with reference to  FIG. 5 . An RF chip  5 A of the plug  1 A shown in  FIG. 5  serves as an example of a second wireless communication section, and is provided at a portion opposite to an RF chip  6  of the connector  2  so as to perform wireless communication. The main surface  5   a  (output surface of an RF signal) of the RF chip  5 A of the plug  1 A is sealed with a resin or the like so that the RF chip  5 A is not exposed. This allows the RF chip  5 A to be protected against stress at the time of attachment/detachment and the effects of temperature and moisture. 
         [0048]    The aperture section  8  of the connector  2  is open to a size that allows the protruding section  7  of the plug  1 A to be inserted. A second RF chip  6  is provided on the top of the aperture section  8 . The RF chip  6  serves as an example of a first wireless communication section, and is provided at a position opposite to the RF chip  5 A of the plug  1 A so as to perform wireless communication. In this example, in order to protect the RF chip  6  against the stress at the time of attachment/detachment, a main surface  6   a  (output surface of an RF signal) of the RF chip  6  is sealed with a resin or the like so that the RF chip  6  is not exposed. 
         [0049]    In addition, the RF chip  5 A and the RF chip  6  are positioned so that, when the protruding section  7  of the plug  1 A is inserted and fit into the aperture section  8  of the connector  2 , the RF chip  5 A provided in the protruding section  7  is opposite to the RF chip  6  provided on the top of the aperture section  8 . 
         [0050]    Hemispherical recessed portions  11  are provided on both sides of the aperture section  8  of the connector  2 . Each hemispherical protruding portion  12  on the plug  1 A shown in  FIG. 7A  is engaged with each recessed portion  11  when the plug  1 A is fit into the connector  2 . This can prevent the plug  1 A from slipping out of the connector  2 , as well as allowing the positions of the RF chip  5 A of the plug  1 A and the RF chip  6  of the connector  2  to be defined precisely. Naturally, a method of fixing the plug  1 A to the connector  2  is not limited to the above-described method, and other methods may be used. 
         [0051]    The RF chip  5 A of the plug  1 A receives an optical signal propagating through the combined electrical and optical cable  10 , converts the optical signal into an electric signal (RF signal), and transmits the electric signal to the RF chip  6  of the connector  2 . The RF chip  6  of the connector  2  receives the electric signal (RF signal) transmitted from the plug  1 A, and outputs the signal to a subsequent-stage processing section, which performs processing such as amplification. Further, the RF chip  5 A receives the electric signal (RF signal) transmitted by the RF chip  6  of the connector  2 , converts the signal into an optical signal, and emits the optical signal to the combined electrical and optical cable  10 . 
         [0052]    In this manner, when the plug  1 A is fit into the connector  2 , the RF chip  5 A of the plug  1 A and the RF chip  6  of the connector  2  can perform data communication in a non-contact state. This allows the plug  1 A to be easily attached to/detached from the connector  2  without breaking the RF chips  5 A and  6 . 
         [0053]    An example of the fitting of the plug  1 A will be described with reference to  FIGS. 6A and 6B . As shown in  FIG. 6A , the front end of the protruding section  7  of the plug  1 A is inserted into the aperture section  8  in the connector  2 . After insertion, the plug  1 A is pushed and slid in the direction of an arrow P. When the plug  1 A is slid, each protruding portion  12  on the plug  1 A (see  FIG. 7A ) abuts against a front face  4   a  of the connector  2 . After the abutting, when the plug  1 A is further pushed in the direction of the arrow P, due to each abutting protruding portion  12 , the connector body  4  becomes slightly bent such that the aperture section  8  of the connector  2  widens laterally. With the connector body  4  bent, when the plug  1 A is further pushed and slid in the direction of the arrow P until the position shown in  FIG. 6B  is reached, each protruding portion  12  on the plug  1 A snaps into the recessed portion  11  on the connector  2  (see  FIG. 5 ), and the bending is reverted. In this manner, the plug  1 A is fit into the connector  2 . 
         [0054]    Subsequently, an example of the configuration of the plug  1 A will be described in detail with reference to  FIGS. 7A to 8B . The plug  1 A shown in  FIG. 7A  has hemispherical protruding portions  12  on both sides near the root of the protruding section  7 . These protruding portions  12  snap into the recessed portions  11  on the plug  1 A as described in connection with  FIG. 5 . 
         [0055]      FIG. 7B  is a cross sectional view in the X 1 -X 1  arrow direction illustrating the plug  1 A of  FIG. 7A . The main surface  5   a  (output surface of an RF signal) of the RF chip  5 A of the plug  1 A shown in  FIG. 7B  is sealed with a resin or the like and provided in the protruding section  7 . The RF chip  5 A of the plug  1 A is positioned so that the upper surface  7   a  of the protruding section  7  is orthogonal to the direction normal to the main surface  5   a  of the RF chip  5 A. 
         [0056]    The RF chip  5 A is connected to the combined electrical and optical cable  10 . An optical fiber  18  of the combined electrical and optical cable  10  is covered with a coating member  19  such as a resin. The RF chip  5 A receives an optical signal propagating through the optical fiber  18 , which is an example of an optical transmission path, converts the optical signal into an electric signal (RF signal), and transmits the electric signal in the direction normal to the main surface  5   a . Further, the RF chip  5 A receives the electric signal (RF signal) transmitted by the RF chip  6  of the connector  2  in the direction normal to the main surface  5   a , converts the signal into an optical signal, and emits the optical signal to the optical fiber  18 . 
         [0057]      FIG. 8B  is a cross sectional view in the X 2 -X 2  arrow direction illustrating the plug  1 A of  FIG. 8A . The RF chip  5 A of the plug  1 A shown in  FIG. 8B  includes an antenna section  13 , an amplifier  14 , a light receiving section  15 , an optical modulator  16  and an LD (Laser Diode)  17 . The antenna section  13  has directivity, and receives/transmits RF signals in a particular direction. 
         [0058]    When the antenna section  13  receives an RF signal, the amplifier  14  connected to the antenna section  13  and optical modulator  16  amplifies the electric signal output from the antenna section  13  and outputs the signal to the optical modulator  16 . The optical modulator  16  is connected to the LD  17  and the optical fiber  18 , and modulates the optical signal received from the LD  17  based on the amplified electric signal. The optical modulator  16  emits the modulated optical signal to the optical fiber  18 . In this example, power is supplied to the LD  17  through a contact terminal No. 18 (see  FIG. 9 ). The LD  17  is connected to a light supply cable  20 , and emits an optical signal to the light supply cable  20 . The plug  1 B shown in  FIG. 4  receives the optical signal from the light supply cable  20 , and modulates the optical signal based on a predetermined electric signal. 
         [0059]    Further, when the optical signal propagates from the optical fiber  18 , the light receiving section  15  receives the optical signal from the optical fiber  18 . The light receiving section  15  is connected to the amplifier  14 , converts the received optical signal into an electric signal, and outputs the electric signal to the amplifier  14 . The amplifier  14  amplifies and outputs the electric signal to the antenna section  13 . The antenna section  13  emits the electric signal as an RF signal. 
         [0060]    Subsequently, an example of the configuration of the RF chip  5 A of the plug  1 A will be described with reference to  FIG. 9 . The RF chip  5 A shown in  FIG. 9  functionally corresponds to the HDMI (Registered Trademark) connector  200  according to a conventional example shown in  FIGS. 1 and 2 , for example. Namely, the RF chip  5 A has four channels in total: optical fibers  18  for data transmission (channels CH 1  to CH 3 ) and an optical fiber  18  for clock transmission (channel CH 4 ). In addition, the RF chip  5 A has contact terminals No. 13 to No. 19 corresponding to the Pin  13  to Pin  19  in the HDMI (Registered Trademark) connector  200  shown in  FIG. 2 . Each of these contact terminals No. 13 to No. 19 is connected to each power supply signal cable  23 . Since the function of the contact terminals No. 13 to No. 19 is well known, it is not described. 
         [0061]    The antenna section  13  includes four RX (receiving) antennas  13   a  and four TX (transmitting) antennas  13   b . In order to realize miniaturization, the arrangement pitch between RX antennas  13   a  is about 1 mm at most. In order to realize miniaturization, the arrangement pitch between TX antennas  13   b  is also about 1 mm at most. The RX antennas  13   a  receive RF signals. The TX antennas  13   b  emit RF signals. 
         [0062]    In this example, when a plurality of the RX antenna  13   a  and the TX antenna  13   b  combinations are to be positioned, the power supply to the RX antennas  13   a  and the TX antennas  13   b  is restricted in order to prevent interference (crosstalk). For example, a power supply section  54  connected to the contact terminal No. 18 of the RF chip  6  of the connector  2  shown in  FIG. 16  restricts the power supplied to the RX antennas  13   a  and the TX antennas  13   b  of the RF chip  5 A of the plug  1 A. In this example, the contact terminal No. 18 of the RF chip  5 A shown in  FIG. 9  and the contact terminal No. 18 of the RF chip  6  shown in  FIG. 16  are connected to each other. A predetermined voltage is applied from the power supply section  54  to the contact terminal No. 18 of the RF chip  6  shown in  FIG. 16 . At that time, a predetermined power is supplied to the contact terminal No. 18 of the RF chip  5 A shown in  FIG. 9 , which is connected to the contact terminal No. 18 of the RF chip  6  shown in  FIG. 16 . In addition, a predetermined power is supplied to the RX antennas  13   a  and the TX antennas  13   b  of the RF chip  5 A. 
         [0063]    Furthermore, when a plurality of the RX antenna  13   a  and the TX antenna  13   b  combinations are to be positioned, the RX antennas  13   a  and the TX antennas  13   b  are positioned by changing the plane of polarization of the RX antennas  13   a  adjacent to each other and the TX antennas  13   b  adjacent to each other in order to prevent interference. For example, the adjacent RX antennas  13   a ,  13   a  are positioned to have circularly polarized waves in different directions of rotation (left-hand circular polarization and right-hand circular polarization) so that the planes of polarization of them are orthogonal to each other. As a result, the crosstalk (interference) between the RX antennas  13   a ,  13   a  adjacent to each other can be suppressed. 
         [0064]    The amplifier  14  includes eight AMPs  14   a . Each AMP  14   a  is connected to each RX antenna  13   a  and TX antenna  13   b . The AMP  14   a  amplifies an electric signal input from the RX antenna  13   a . In addition, the AMP  14   a  amplifies the electric signal input from the light receiving section  15 , and outputs the signal to the TX antenna  13   b.    
         [0065]    The light receiving section  15  includes four light receiving elements (O—R)  15   a . These light receiving elements  15   a  serve as an example of an optical-electric conversion section, are connected to the optical fibers  18  of the channels CH 1  to CH 4  through optical waveguides  22 , and further connected to the TX antennas  13   b  through the AMPs  14   a . The light receiving element  15   a  receives an optical signal propagating through the optical fiber  18 , converts the signal into an electric signal, and outputs the electric signal to the TX antenna  13   b  through the AMP  14   a.    
         [0066]    The optical modulator  16  includes four light modulators (E-O)  16   a . These light modulators  16   a  serve as an example of an electric-optical conversion section, are connected to the RX antennas  13   a  through the AMPs  14   a , and further connected to the LD  17  and the optical fibers  18  of the channels CH 1  to CH 4 . The optical modulator  16   a  converts an electric signal into an optical signal. For example, the optical modulator  16   a  modulates an optical signal received from the LD  17  based on the electric signal input from the RX antenna  13   a  through the AMP  14   a . The optical modulator  16   a  emits the modulated optical signal to the optical fibers  18  of the channels CH 1  to CH 4 . 
         [0067]    Subsequently, an example of the operation of the RF chip  5 A of the plug  1 A will be described. When the RX antenna  13   a  shown in  FIG. 9  receives an RF signal, the RX antenna  13   a  converts the RF signal into a predetermined electric signal, and outputs the electric signal to the AMP  14   a . The AMP  14   a  amplifies the electric signal output from the RX antenna  13   a , and outputs the signal to the optical modulator (E-O)  16   a . The optical modulator  16   a  modulates the optical signal received from the LD  17  based on the amplified electric signal, and emits the modulated optical signal to the optical fibers  18  of the channels CH 1  to CH 4 . 
         [0068]    Further, when the optical signal propagates from the optical fibers  18  of the channels CH 1  to CH 4 , the light receiving element  15   a  receives the optical signal from the optical fiber  18 . The light receiving element  15   a  converts the received optical signal into an electric signal and outputs the electric signal to the AMP  14   a . The AMP  14   a  amplifies and outputs the electric signal to the TX antenna  13   b . The TX antenna  13   b  emits the amplified electric signal as an RF signal. 
         [0069]    Next, an example of the configuration of the RF chip  5 B of the plug  1 B provided on the other side of the connecting cable  1  shown in  FIG. 4  will be described. Since the RF chip  5 B shown in  FIG. 10  receives a light source from the light supply cable  20 , the RF chip  5 B does not have the LD  17  shown in  FIG. 9 . Like components of the RF chip  5 B are denoted by like numerals as of the RF chip  5 A, and the description thereof is omitted. 
         [0070]    The RF chip  5 B has four channels in total: optical fibers  18  for data transmission (channels CH 1  to CH 3 ) and an optical fiber  18  for clock transmission (channel CH 4 ). The optical fibers  18  of these channels CH 1  to CH 4  are connected to the optical fibers  18  of the CH 1  to CH 4  shown in  FIG. 9 . In addition, the RF chip  5 B has contact terminals No. 13 to No. 19 corresponding to the Pin  13  to Pin  19  in the HDMI (Registered Trademark) connector  200  shown in  FIG. 2 . Each of these contact terminals No. 13 to No. 19 is connected to each power supply signal cable  23 . Each power supply signal cable  23  is connected to each power supply signal cable  23  shown in  FIG. 9 . 
         [0071]    The antenna section  13  includes four RX (receiving) antennas  13   a  and four TX (transmitting) antennas  13   b . The RX antennas  13   a  receive RF signals. The TX antennas  13   b  emit RF signals. 
         [0072]    The amplifier  14  includes eight AMPs  14   a . Each AMP  14   a  is connected to each RX antenna  13   a  and TX antenna  13   b . The AMP  14   a  amplifies an electric signal input from the RX antenna  13   a . In addition, the AMP  14   a  amplifies the electric signal input from the light receiving section  15 , and outputs the signal to the TX antenna  13   b.    
         [0073]    The light receiving section  15  includes four light receiving elements (O-E)  15   a . These light receiving elements  15   a  are connected to the optical fibers  18  of the channels CH 1  to CH 4  through the optical waveguides  22 , and further connected to the TX antennas  13   b  through the AMPs  14   a . The light receiving element  15   a  converts an optical signal propagating through the optical fiber  18  into an electric signal, and outputs the electric signal to the TX antenna  13   b  through the AMP  14   a.    
         [0074]    The optical modulator  16  includes four light modulators (E-O)  16   a . These light modulators  16   a  are connected to the RX antennas  13   a  through the AMPs  14   a , and further connected to the light supply cable  20  and the optical fibers  18  of the channels CH 1  to CH 4 . The optical modulator  16   a  modulates an optical signal received from the light supply cable  20  based on the electric signal input from the RX antenna  13   a  through the AMP  14   a . The optical modulator  16   a  emits the modulated optical signal to the optical fibers  18  of the channels CH 1  to CH 4 . 
         [0075]    Subsequently, an example of the operation of the RF chip  5 B of the plug  1 B will be described. When the RX antenna  13   a  shown in  FIG. 10  receives an RF signal, the RX antenna  13   a  converts the RF signal into a predetermined electric signal, and outputs the electric signal to the AMP  14   a . The AMP  14   a  amplifies the electric signal output from the RX antenna  13   a , and outputs the signal to the optical modulator (E-O)  16   a . The optical modulator  16   a  modulates the optical signal received from the LD  17  shown in  FIG. 9  through the light supply cable  20  based on the amplified electric signal, and emits the modulated optical signal to the optical fibers  18  of the channels CH 1  to CH 4 . 
         [0076]    Further, when the optical signal propagates from the optical fibers  18  of the channels CH 1  to CH 4 , the light receiving element  15   a  receives the optical signal from the optical fiber  18 . The light receiving element  15   a  converts the received optical signal into an electric signal and outputs the electric signal to the AMP  14   a . The AMP  14   a  amplifies and outputs the electric signal to the TX antenna  13   b . The TX antenna  13   b  emits the amplified electric signal as an RF signal. It should be noted that the LD  17  shown in  FIG. 9  may also be mounted on the RF chip  5 B shown in  FIG. 10 . In this case, the light supply cable  20  is not required for the RF chip  5 A and the RF chip  5 B. 
         [0077]    Further, as shown in  FIG. 11 , discrete components such as a light source and a detector (not shown) (light receiving element  15   a  and optical modulator  16   a ) may be positioned on each optical fiber  18 . In this example, this would be a case where components not suitable for mounting on a silicon chip, such as VCSEL, are used for the light source and the detector. In this example, the RX antennas  13   a , the TX antennas  13   b , the AMPs  14   a  and the contact terminals No. 13 to No. 19 are positioned on the chassis  49  of the RF chip  5 C. The light receiving element (O-E)  15   a  and the optical modulator (E-O)  16   a  are not positioned on the chassis  49  of the RF chip  5 C. 
         [0078]    Furthermore, in the optical fiber  18  shown in  FIGS. 9 to 11 , although the optical signal transmission direction is unidirectional, it may also be a bidirectional communication. In this case, the bidirectional communication is easily achieved using a branching optical waveguide  50  as shown in  FIG. 12 . In the RF chip  5 D shown in FIG.  12 , only components related to the channel CH 1  are shown, and components related to the other channels CH 2  to CH 4  and the contact terminals No. 13 to No. 19 are omitted. 
         [0079]    The channel CH 1  shown in  FIG. 12  is constituted by one optical fiber  18 . The optical fiber  18  is connected to the light receiving element  15   a  and the optical modulator  16   a  through the branching optical waveguide  50 . 
         [0080]    The branching optical waveguide  50  transmits an optical signal output from the optical modulator  16   a  to the optical fiber  18 . In addition, the branching optical waveguide  50  transmits the optical signal propagating from the optical fiber  18  to the light receiving element  15   a . As a result, the number of optical fibers  18  to be installed can be reduced, thus reducing the cost. 
         [0081]    Subsequently, the manufacturing process of the RF chip  5 A of the plug  1 A will be described with reference to  FIGS. 13A and 13B . For example, the entire surface of the chassis  49  (substrate) of the RF chip  5 A shown in  FIG. 13A  is lined with a copper foil. With a predetermined screen plate, a pattern is printed and etched on the chassis  49 . After the etching, the remaining photo-sensitive film is striped to expose the copper foil pattern. Then, resist ink having insulation action is applied over the chassis  49 , and is dried and developed to expose a circuit and the contact terminals No. 13 to No. 19. The material of the chassis  49  is a silicone resin, for example. 
         [0082]    Subsequently, in order to form an alignment groove  53  for optical fiber shown in  FIG. 13A , nine predetermined positions on the chassis  49  are cut in rectangles with a substrate processing machine. The alignment groove  53  is not limited to a rectangular shape, and may have a V-shape. After the alignment groove  53  is formed, the optical waveguide  22  is mounted by adhesion to the predetermined portion with an adhesive agent. Then, the antenna section  13 , the amplifier  14 , the light receiving element  15   a , and the optical modulator  16   a  are mounted on predetermined positions on the chassis  49 . Subsequently, as shown in  FIG. 13B , the LD  17  is mounted on a predetermined position on the chassis  49 , and each optical fiber  18  and the light supply cable  20  are mounted by adhesion to the alignment groove  53  with an adhesive agent. At that time, the cores of the optical fiber  18  and the light supply cable  20  are mounted by alignment with the core of the optical waveguide  22 . 
         [0083]    Subsequently, an example of the configuration of the connector  2  will be described in detail with reference to  FIGS. 14A to 15B .  FIG. 14B  is a cross sectional view in the X 3 -X 3  arrow direction of  FIG. 14A  illustrating the example of the configuration of the connector  2 . For ease of understanding the description herein, in  FIG. 14B , the plug  1 A fit into the connector  2  is shown in a chain double-dashed line. The main surface  6   a  (output surface of an RF signal) of the RF chip  6  of the connector  2  shown in  FIG. 14B  is sealed with a resin or the like and provided in the connector body  4 . The RF chip  6  is positioned so that the upper surface  8   a  of the aperture section  8  is orthogonal to the direction normal to the main surface  6   a  of the RF chip  6 . 
         [0084]    Namely, the RF chip  5 A and the RF chip  6  are positioned so that the direction of insertion of the plug  1 A into the connector  2  is orthogonal to the direction normal to the output surface of the RF signal emitted from the RF chip  5 A of the plug  1 A and the RF chip  6  of the connector  2 . Thus, the main surface  6   a  of the RF chip  6  of the connector  2  is parallel with the main surface  5   a  of the RF chip  5 A of the plug  1 A inserted into the aperture section  8  of the connector  2 . Accordingly, the RF signal emitted from the main surface  5   a  of the RF chip  5 A accurately reaches the main surface  6   a  of the RF chip  6 . Similarly, the RF signal emitted from the main surface  6   a  of the RF chip  6  accurately reaches the main surface  5   a  of the RF chip  5 A. 
         [0085]    In this example, the RF chip  6  of the connector  2  is connected to a signal processing section  51  of the projector  21  shown in  FIG. 16 . The RF chip  6  receives an RF signal from the plug  1 A, converts the RF signal into an electric signal, and outputs the electric signal to the signal processing section  51 . In addition, the RF chip  6  converts an electric signal output from an RF circuit  52  shown in  FIG. 16  into an RF signal, and emits the RF signal. 
         [0086]      FIG. 15B  is a cross sectional view in the X 4 -X 4  arrow direction illustrating the connector  2  of  FIG. 15A . The RF chip  6  of the connector  2  shown in  FIG. 15B  includes an antenna section  24 . The antenna section  24  has directivity, and receives/transmits RF signals in a particular direction. 
         [0087]    When the antenna section  24  receives an RF signal, the antenna section  24  converts the RF signal into a predetermined electric signal, and outputs the electric signal to the signal processing section  51  shown in  FIG. 16 . The signal processing section  51  performs predetermined signal processing such as amplification on the output electric signal. Further, the antenna section  24  is connected to an RF circuit  52  shown in  FIG. 16 , and emits the electric signal output from the RF circuit  52  as an RF signal. 
         [0088]    Subsequently, an example of the configuration of the RF chip  6  and the RF circuit  52  will be described with reference to  FIG. 16 . The RF chip  6  shown in  FIG. 16  includes the antenna section  24 . The antenna section  24  includes four RX (receiving) antennas  24   a  and four TX (transmitting) antennas  24   b . The RX antenna  24   a  is connected to the signal processing section  51 , and converts a received RF signal into an electric signal, and outputs the electric signal to the signal processing section  51 . The TX antenna  24   b  is connected to the RF circuit  52 , and emits the electric signal input from the RF circuit  52  as an RF signal. 
         [0089]    The RF circuit  52  includes an LNA (Low Noise Amplifier)  52   a , a Mixer  52   b , an oscillator  52   c  and a filter  52   d . The LNA  52   a  amplifies an input predetermined electric signal and outputs the electric signal to the Mixer  52   b . The Mixer  52   b  is connected to the LNA  52   a  and the oscillator  52   c . The oscillator  52   c  oscillates a frequency of 60 GHz, for example. The Mixer  52   b  synthesizes (modulates) the 60 GHz frequency signal and the electric signal amplified by the LNA  52   a , and outputs the synthesized electric signal to the filter  52   d . The filter  52   d  serves as a highpass filter, for example, and removes a low-frequency component from the output electric signal. The filter  52   d  outputs to each TX antenna  24   b  the electric signal from which the low-frequency component was removed. The TX antenna  24   b  emits the output electric signal as an RF signal. 
         [0090]    It is assumed that the frequency of the RF signal is at 60 GHz. The first reason is that the RF circuit  52  can be formed on a silicon substrate. Since the actual value of a gain-bandwidth product (ft) of a 90 nm node MOS transistor is about 140 GHz, the configuration supporting 60 GHz is possible as far as a mass-production technique is concerned. The second reason is that an antenna can be miniaturized. The third reason is that the frequency of 60 GHz is in a band region where electric-optical conversion is possible using a micro ring modulator. The fourth reason is that if the carrier is at 60 GHz, the capacity of transmission at about 10 Gbps can be secured. When a transport rate is low, a carrier of 40 GHz, 25 GHz or the like may be used. In this case, semiconductor components can be created at a lower price. 
         [0091]    In this manner, according to the attachable/detachable connector system  100  of the present invention, the connector  2  provided on the projector  21  has the RF chip  6 , and the plug  1 A connected to the connector  2  has the RF chip  5 A at a position opposite to the RF chip  6  of the connector  2 . 
         [0092]    Accordingly, when the plug  1 A is connected to the connector  2 , the RF chip  5 A of the plug  1 A and the RF chip  6  of the connector  2  can perform wireless communication with each other in a non-contact state. Thus, the plug  1 A can be easily attached to/detached from the connector  2  without breaking a terminal due to contact such as in a case where the conventional contact type terminal is used. 
         [0093]    Further, in the connector  200  (e.g., version 1.3) shown in  FIG. 1 , for example, when data communication speed of 10 Gbps is realized, the electric signal is attenuated with increasing data transmission distance. Therefore, transmitting data over long distances (about 20 mm) is difficult, and for example, hardwiring to a projector installed on a ceiling is not straightforward. On the other hand, the attachable/detachable connector system  100  can prevent the attenuation of the data because the optical fiber  18  transmits the data, thus long-distance transmission is possible. Therefore, even at a location such as the projector  21  installed on the ceiling, the attachable/detachable connector system  100  can be used. In addition, a low cost device can be realized by forming with silicon all the components other than light emitting components. 
         [0094]    The present embodiments may be applied to a connector cable that connects a video reproducer and a display. 
         [0095]    It should be understood that various changes and modifications to the presently preferred embodiments described herein will be apparent to those skilled in the art. Such changes and modifications can be made without departing from the spirit and scope of the present invention and without diminishing its intended advantages. It is therefore intended that such changes and modifications be covered by the appended claims.