Abstract:
The invention provides a device for making parallel interface communication compatible with serial interface communication when a serial interface compatible large television lens is used for a portable television camera, thereby performing optimal communication between the television camera and lens. In the arrangement of this invention, the terminals of the television lens are connected to the terminals of the camera via an adapter device, and a changeover switch is used to connect the terminals in accordance with serial or parallel communication, thereby setting compatibility between serial and parallel communications.

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to an electrical interface between a television camera and television lens. 
     2. Related Background Art 
     Electrical interfaces between the television camera and television lens are mainly classified into a 36-pin parallel (analog) interface using a 36-pin connector for a high-performance, multifunctional, expensive large television camera and large television lens and a 12-pin parallel (analog) interface using a 12-pin connector for compact, lightweight, low-cost portable television camera and television lens. One function is assigned to each pin of each of these electrical interfaces. For example, an iris control signal for controlling the iris of the television lens from the television camera is assigned to the fifth pin of the 12-pin parallel interface for the portable television camera and to the 17th pin of the 36-pin parallel interface for the large television camera. 
     FIG. 4 is a block diagram of a 12-pin parallel interface between the conventional portable television camera and portable television lens. The electrical interface between a portable television camera  200  and portable television lens  700  has a 12-pin connector  500  (only the 1st, 3rd, 4th, 5th, 6th, and 7th pins are illustrated, and an illustration of other pins is omitted). In the direction from the portable television camera  200  to the portable television lens  700 , the electrical interface sends a switch input signal mainly having a function of switching the iris automatically or manually and an analog input signal represented by the iris control signal. In the direction from the portable television lens  700  to the portable television camera  200 , the electrical interface sends a switch output signal mainly having a function of ON/OFF-switching VTR recording and an analog output signal represented by an iris position signal. 
     The internal arrangement of the portable television lens  700  will be described below. 
     The switch input signal is input to an analog control signal calculation portion  115  to make the portable television lens  700  function in accordance with the contents of the switch input signal. The analog input signal is sequentially supplied to the analog control calculation portion  115 , a driver circuit  111  for driving a motor, and a motor  110  for operating an optical system (not shown) such as a focus lens group, zoom lens group, iris blades, and extender lens group. A position detector  108  for detecting the state of the optical system in cooperation with the motor  110  is attached to the optical system. A signal from the position detector  108  is output as an analog output signal to the portable television camera  200  via an analog position signal calculation portion  109 . Information from a switch  119  in the portable television lens  700  is also output as a switch output signal to the portable television camera  200 . 
     In recent years, along with the improvement in performance of portable television cameras, a large television lens is often used for a portable television camera. In this case, a 36-pin/12-pin interface conversion adapter is generally used between the portable television camera and large television lens. 
     To implement higher performance to cope with a virtual studio, a 12-pin parallel interface and 36-pin parallel interface as an electrical interface between a television camera and television lens, and a 12-pin serial interface and 36-pin serial interface assigned with a function of two-way serial communication from a television camera to television lens and from a television lens to television camera are used more often because further expansion and higher precision are difficult with state-of-the-art electrical interfaces for television camera lenses. With reference to the presence/absence of serial communication, the interface of a television lens having such a serial communication function is automatically switched to a serial interface when a television camera to which the television lens is attached has a serial communication function or to a parallel interface when a television camera to which the television lens is attached does not have a serial communication function. 
     Serial communication functions are assigned to parallel interfaces as follows. In the 12-pin parallel interface, the serial communication function is assigned to the 11th pin as a focus position signal pin which is rarely used and the 12th pin as an unused pin. 
     In the 36-pin parallel interface, the serial communication function is assigned to the extender position signal pin and iris mode changeover signal since no unused pin is available. The function of serial communication from the television lens to television camera is assigned to the 11th pin in the 12-pin serial interface and the 8th pin in the 36-pin serial interface. In use of a large television lens having a serial communication function in a portable television camera having a serial communication function, conversion must be performed by a 36-pin/12-pin interface conversion adapter so as to connect the 8th pin of the 36-pin connector to the 11th pin of the 12-pin connector. Since the focus position signal and extender position signal are respectively assigned to the 11th pin of the 12-pin parallel interface and the 8th pin of the 36-pin parallel interface, the following problem is posed in the parallel interface mode. That is, in use of a large television lens having a serial communication function in a portable television camera having no serial communication function, i.e., a parallel interface, when the 36-pin/12-pin interface conversion adapter is used, the portable television camera erroneously detects the extender position signal from the large television lens as a focus position signal. 
     SUMMARY OF THE INVENTION 
     One aspect of the application is to provide a system, adapter, and lens to cope with parallel and serial communications between a camera and lens having different numbers of pins. 
     One aspect of the application is to provide a photographic system for connecting a camera and a second lens unit via an adapter device, the camera having a plurality of terminals compatible with a first lens unit having a plurality of terminals and having parallel and serial communication functions with the first lens unit via the pluralities of terminals, the second lens unit having a terminal arrangement different from that of the first lens unit, and the adapter device connecting a first terminal of the camera, which is used as a terminal for first information in parallel communication and a terminal for serial communication in communicating information serially, to a first terminal of the second lens unit, which is used as a terminal for transmitting the first information in the parallel communication, and connecting a second terminal of the camera, which is used as a terminal of the camera for second information in the parallel communication, to a second terminal of the second lens unit, which is used as a terminal of the camera for the second information in the parallel communication and a terminal for serial communication in communicating information serially, and the photographic system allowing compatible connection between the camera and second lens unit in parallel communication, comprising a changeover switch which connects the first terminal of the camera and the second terminal of the second lens unit, thereby eliminating the conventional drawback described above. 
     One aspect of the application is to provide an adapter device for connecting a camera and a second lens unit, the camera having a plurality of terminals compatible with a first lens unit having a plurality of terminals and having parallel and serial communication functions with the first lens unit via the pluralities of terminals, the second lens unit having a terminal arrangement different from that of the first lens unit, and the adapter device connecting a first terminal of the camera, which is used as a terminal for first information in parallel communication and a terminal for serial communication in communicating information serially, to a first terminal of the second lens unit, which is used as a terminal for the first information in the parallel communication, and connecting a second terminal of the camera, which is used as a terminal for second information in the parallel communication, to a second terminal of the second lens unit, which is used as a terminal for the second information in the parallel communication and a terminal for serial communication in communicating information serially, and the adapter device allowing compatible connection between the camera and second lens unit in parallel communication, comprising a changeover switch which connects the first terminal of the camera and the second terminal of the second lens unit, thereby eliminating the conventional drawback described above. 
     One aspect of the application is to provide a photographic system for connecting a camera and a second lens unit via an adapter device, the camera having a plurality of terminals compatible with a first lens unit having a plurality of terminals and having parallel and serial communication functions with the first lens unit via the pluralities of terminals, the second lens unit having a terminal arrangement different from that of the first lens unit, and the adapter device connecting a first terminal of the camera, which is used as a terminal for transmitting first information in parallel communication, to a first terminal of the second lens unit, which is used as a terminal for transmitting the first information in the parallel communication and a terminal for serial communication in communicating information serially, and the photographic system allowing compatible connection between the camera and second lens unit in parallel communication, comprising a changeover switch which connects a second terminal of the camera, which is used as a terminal for serial communication, and the first terminal of the second lens unit, thereby eliminating the conventional drawback described above. 
     One aspect of the application is to provide an adapter device for connecting a camera and a second lens unit, the camera having a plurality of terminals compatible with a first lens unit having a plurality of terminals and having parallel and serial communication functions with the first lens unit via the pluralities of terminals, the second lens unit having a terminal arrangement different from that of the first lens unit, and the adapter device connecting a first terminal of the camera, which is used as a terminal for first information in parallel communication, to a first terminal of the second lens unit, which is used as a terminal for the first information in the parallel communication and a terminal for serial communication in communicating information serially, and the adapter device allowing compatible connection between the camera and second lens unit in parallel communication, comprising a changeover switch which connects a second terminal of the camera, which is used as a terminal for serial communication, and the first terminal of the second lens unit, thereby eliminating the conventional drawback described above. 
     One aspect of the application is to provide a photographic system for connecting a camera and a second lens unit via an adapter device, the camera having a plurality of terminals compatible with a first lens unit having a plurality of terminals and having parallel and serial communication functions with the first lens unit via the pluralities of terminals, the second lens unit having a terminal arrangement different from that of the first lens unit, and the adapter device connecting a first terminal of the camera, which is used as a terminal for first information in parallel communication and a terminal for serial communication in communicating information serially, to a first terminal of the second lens unit, which is used as a terminal for the first information in the parallel communication, and connecting a second terminal of the camera to a second terminal of the second lens unit, which is used as a terminal for serial communication in communicating information serially, and the photographic system allowing compatible connection between the camera and second lens unit in parallel communication, comprising a changeover switch which connects a serial communication line in the second lens unit to a first terminal of the second lens unit, thereby eliminating the conventional drawback described above. 
     One aspect of the application is to provide a first lens unit connected to a camera via an adapter device, the camera having a plurality of terminals compatible with a first lens unit having a plurality of terminals and having parallel and serial communication functions with the first lens unit via the pluralities of terminals, the lens unit having a terminal arrangement different from that of the first lens unit, and the adapter device connecting a first terminal of the camera, which is used as a terminal for first information in parallel communication and a terminal for serial communication in communicating information serially, to a first terminal of the lens unit, which is used as a terminal for the first information in the parallel communication, and connecting a second terminal of the camera to a second terminal of the lens unit, which is used as a terminal for serial communication in communicating information serially, and the lens unit allowing compatible connection between the camera and lens unit in parallel communication, comprising a changeover switch which connects a serial communication line in the lens unit to a first terminal of the lens unit, thereby eliminating the conventional drawback described above. 
     One aspect of the application is to provide a photographic system for connecting a camera and a second lens unit via an adapter device, the camera having a plurality of terminals compatible with a first lens unit having a plurality of terminals and having parallel and serial communication functions with the first lens unit via the pluralities of terminals, the second lens unit having a terminal arrangement different from that of the first lens unit, and the adapter device connecting a first terminal of the camera, which is used as a terminal for first information in parallel communication, to a first terminal of the second lens unit, which is used as a terminal for the first information in the parallel communication and a terminal for serial communication in communicating information serially, and the photographic system allowing compatible connection between the camera and second lens unit in parallel communication, comprising a changeover switch which connects a serial line in the second lens unit to a second terminal of the camera, which is used as a terminal for serial communication, and a second terminal of the second lens unit, which is connected via the adapter device, thereby eliminating the conventional drawback described above. 
     One aspect of the application is to provide a lens unit connected to a camera via an adapter device, the camera having a plurality of terminals compatible with a first lens unit having a plurality of terminals and having parallel and serial communication functions with the first lens unit via the pluralities of terminals, the lens unit having a terminal arrangement different from that of the first lens unit, and the adapter device connecting a first terminal of the camera, which is used as a terminal for first information in parallel communication, to a first terminal of the lens unit, which is used as a terminal for the first information in the parallel communication and a terminal for serial communication in communicating information serially, and the lens unit allowing compatible connection between the camera and lens unit in parallel communication, comprising a changeover switch which connects a serial line in the lens unit to a second terminal of the camera, which is used as a terminal for serial communication, and a second terminal of the lens unit, which is connected via the adapter device, thereby eliminating the conventional drawback described above. 
     One aspect of the application is to provide a photographic system for connecting a camera and a second lens unit via an adapter device, the camera having a plurality of terminals compatible with a first lens unit having a plurality of terminals and having parallel and serial communication functions with the first lens unit via the pluralities of terminals, the second lens unit having a terminal arrangement different from that of the first lens unit, and the adapter device making the terminals of the camera and second lens unit compatible with each other in the parallel communication to allow parallel communication between the camera and second lens, comprising a changeover switch which uses a predetermined terminal, of the camera connected to a terminal of the second lens unit in parallel communication and used as a terminal for parallel communication, as a terminal for serial communication in communicating information serially, and connects a serial line in the second lens unit to the predetermined terminal of the camera in serial communication, thereby eliminating the conventional drawback described above. 
     One aspect of the application is to provide an adapter device for connecting a camera and a second lens unit, the camera having a plurality of terminals compatible with a first lens unit having a plurality of terminals and having parallel and serial communication functions with the first lens unit via the pluralities of terminals, the second lens unit having a terminal arrangement different from that of the first lens unit, and the adapter device making the terminals of the camera and second lens unit compatible with each other in the parallel communication to allow parallel communication between the camera and second lens, comprising a changeover switch which switches, in serial communication, a parallel/serial terminal of the camera, which is connected to a predetermined terminal of the second lens unit by the adapter device in parallel communication and used as a terminal for parallel communication, to another terminal of the second lens unit, which is connected to a serial line of the second lens unit, thereby eliminating the conventional drawback described above. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG.  1 . is a block diagram of an arrangement between a large television lens and portable television camera according to the first embodiment of the present invention; 
     FIG. 2 is a block diagram of an arrangement between a large television lens and portable television camera according to the second embodiment of the present invention; 
     FIG. 3 is a block diagram of an arrangement between a large television lens and large television camera according to the second embodiment of the present invention; and 
     FIG. 4 is a block diagram of a conventional arrangement between a television lens and television camera. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     First Embodiment 
     The first embodiment of the present invention will be described below with reference to the accompanying drawings. 
     FIG. 1 is a block diagram of an interface between a portable television camera and large television lens according to the first embodiment of the present invention. 
     Referring to FIG. 1, a 36-pin/12-pin interface conversion adapter  300  connects a large television lens  100  to a portable television camera  200 . A 36-pin connector (only the 4th, 5th, 8th, 12th, 14th, 16th, 17th, and 18th pins are shown, and an illustration of the remaining pins is omitted)  400  connects the large television lens  100  to the 36-pin/12-pin interface conversion adapter  300 . A 12-pin connector (only the 1st, 3rd, 5th, 6th, 7th, 8th, 9th, 11th, and 12th pins are shown, and an illustration of the remaining pin is omitted)  500  connects the portable television camera  200  to the 36-pin/12-pin interface conversion adapter  300 . Note that the lens  100  can be connected to a large camera (36 pins) directly without connecting the 36-pin connector of the camera and the 36-pin connector of the lens via an adapter. 
     The internal arrangement of the large television lens  100  will be described below. 
     The large television lens  100  has a focus lens group  101  for performing focus control, zoom lens group  102  for performing zooming, relay lens group  103  for imaging control, iris blades  104  for adjusting the stop, and extender lens group  105  for converting the magnification range. These lens groups constitute the optical system of the large television lens  100 . 
     A focus position detector  106  detects the position of the focus lens group  101 . A focus position signal calculation portion  107  performs arithmetic operation for a signal from the focus position detector  106 . Components  108  to  115  (to be described later) are required for each of the iris and zoom portions, but are represented by single components, respectively. The analog position detector  108  detects the position of the stop of the iris blades  104  and the position of the zoom lens group  102 . The analog position signal calculation portion  109  performs arithmetic operation for a signal from the analog position detector  108 . The motor  110  drives the iris blades  104  an the zoom lens group  102 . The driver circuit  111  drives the motor  110 . The extender position detector  112  detects the position of the extender lens group. The extender position signal calculation portion  113  performs arithmetic operation for a signal from the extender position detector  112 . The iris servo gain converter (not required in a zoom servo system)  114  changes the gain of the iris servo system in accordance with an iris mode changeover signal from the portable television camera  200 . The analog control signal calculation portion  115  performs arithmetic operation for a control signal from the portable television camera  200 . A/D converters  116 ,  117 , and  118  supply signals from the focus position signal calculation portion  107 , analog signal position calculation portion  109 , and extender position signal calculation portion  113 , respectively, to a CPU  120  (to be described later). A switch  119  has the main function of ON/OFF-switching VTR recording. The CPU  120  controls the serial communication function. A 36-pin interface changeover portion  121  switches the 36-pin serial interface and 36-pin parallel interface. An interface determination portion  122  determines by the presence/absence of a serial communication signal whether the connected portable television camera  200  has a serial or parallel interface, and controls the 36-pin interface changeover portion  121 . 
     The internal arrangement of the 36-pin/12-pin interface conversion adapter  300  will be described below. 
     A 12-pin interface changeover portion  301  switches the 12-pin serial interface and 12-pin parallel interface. An interface determination portion  302  determines whether the connected portable television camera  200  has a serial or parallel interface, and controls the 12-pin interface changeover portion  301 . 
     In the above arrangement, when the portable television camera  200  has a 12-pin serial interface, a serial communication signal is output from the 12th pin of the 12-pin connector  500 . This serial communication signal is detected by the interface determination portion  302  in the 36-pin/12-pin interface conversion adapter  300  to switch the 12-pin interface changeover portion  301  to the serial interface mode. The serial communication signal output from the portable television camera  200  passes through the 18th pin of the 36-pin connector  400  and is input to the large television lens  100 . In the large television lens  100 , the serial communication signal is detected by the interface determination portion  122  to switch the 36-pin interface changeover portion  121  to the serial interface mode. 
     When the portable television camera  200  is not compatible with the 12-pin serial interface, no serial communication signal is output from the 12th pin of the 12-pin connector  500 . Since the interface determination portion  302  in the 36-pin/12-pin interface conversion adapter  300  can detect no serial communication signal, the interface of the portable television camera  200  is determined as a parallel interface to switch the 12-pin interface changeover portion  301  to the parallel interface mode. Since no serial communication signal can be detected by the interface determination portion  122  in the large television lens  100 , either, the interface determination portion  122  determines the interface of the portable television camera  200  as a parallel interface to switch the 36-pin interface changeover portion  121  to the parallel interface mode. 
     In the first embodiment, the interface determination portion  302  in the 36-pin/12-pin interface conversion adapter  300  detects the serial communication signal to switch the 12-pin interface changeover portion  301 . However, the 12-pin interface changeover portion  301  may be manually switched. In this case, a changeover member is mounted on the adapter  300  to allow manual changeover. 
     In the first embodiment, the interface determination portion  302  in the 36-pin/12-pin interface conversion adapter  300  detects the serial communication signal to switch the 12-pin interface changeover portion  301 . However, these operations may be performed on the portable television camera  200  side. 
     As described above, one of the 36-pin/12-pin interface conversion adapter interposed between the large television lens and portable television camera includes a means for determining whether the camera has a serial or parallel interface and an interface changeover means. Any connection errors of the serial and parallel interfaces in connection of the serial interface compatible large television lens to the portable television camera can be eliminated. 
     Second Embodiment 
     In the first embodiment, the 36-pin/12-pin interface conversion adapter interposed between the large television lens and portable television camera has the serial/parallel interface changeover function. In the second embodiment, however, a large television lens has the interface changeover function. 
     The second embodiment of the present invention will be described with reference to FIG.  2 . 
     FIG. 2 is a block diagram of an interface between a portable television camera and large television lens according to the second embodiment of the present invention. 
     Referring to FIG. 2, a 36-pin/12-pin interface conversion adapter  300  connects a large television lens  100  to a portable television camera  200 . A 36-pin connector (only the 4th, 5th, 8th, 12th, 14th, 16th, 17th, 18th and 19th pins are shown, and an illustration of the remaining pins is omitted)  400  connects the large television lens  100  to the 36-pin/12-pin interface conversion adapter  300 . A 12-pin connector (only the 1st, 3rd, 5th, 6th, 7th, 8th, 9th, 11th, and 12th pins are shown, and an illustration of the remaining pin is omitted)  500  connects the portable television camera  200  to the 36-pin/12-pin interface conversion adapter  300 . 
     The internal arrangement of the large television lens  100  will be described below. 
     Components  101  to  121  are identical to those in the first embodiment, and a detailed description thereof will be omitted. 
     A serial communication changeover portion  123  changes pin assignment of the serial communication function in accordance with a television camera connected to the lens. An interface determination portion  124  determines based on the presence/absence of serial communication data whether the connected television camera  200  has a 12-pin serial interface, 36-pin serial interface, or parallel interface and controls the 36-pin interface changeover portion  121  and a serial communication changeover portion  123 . 
     The 36-pin/12-pin interface conversion adapter  300  is a conventional one in which wiring lines are changed only for matching between the 36-pin parallel interface and 12-pin parallel interface. 
     In the above arrangement, when the portable television camera  200  is compatible with the 12-pin serial interface, a serial communication signal is input to the 19th pin of the 36-pin connector  400  via the 12th pin of the 12-pin connector  500 . This serial communication signal is detected by the interface determination portion  124  in the large television lens  100  to switch the 36-pin interface changeover portion  124  to the serial interface mode. At the same time, the interface determination portion  124  also detects the serial communication signal input from the 19th pin side of the 36-pin connector  400  to switch the serial communication changeover portion  123  to 12-pin interface side and to perform the serial communication mode. 
     When the portable television camera  200  is not compatible with the 12-pin serial interface, no serial communication signal is input from the 12th pin of the 12-pin connector  500  and the 19th pin of the 36-pin connector  400 . Since the interface determination portion  124  in the large television lens  100  detects no serial communication signal, the interface of the camera is determined as a parallel interface to switch the 36-pin interface changeover portion  121  to the parallel interface mode. 
     FIG. 3 is a block diagram when the large television lens of the second embodiment is used for a large television camera. 
     As shown in FIG. 3, a large television camera  600  and the large television lens  100  have 36-pin interfaces. In this case, no 36-pin/12-pin interface conversion adapter is used. 
     In the above arrangement, when the large television camera  600  is compatible with the 36-pin serial interface, a serial communication signal is input from the 18th pin of the 36-pin connector  400 . This serial communication signal is detected by the interface determination portion  124  in the large television lens  100  to switch the 36-pin interface changeover portion  121  to the serial interface mode. At the same time, the interface determination portion  124  also detects the serial communication signal input from the 18th pin side of the 36-pin connector  400  to switch the serial communication changeover portion  123  to 36-pin interface side and to perform the serial communication mode. 
     When the large television camera  600  is not compatible with the 36-pin serial interface, no serial communication signal is input from the 18th pin of the 36-pin connector  400 . Since the interface determination portion  124  in the large television lens  100  detects no serial communication signal, the interface of the camera is determined as a parallel interface to switch the 36-pin interface changeover portion  121  to the parallel interface mode. 
     In the second embodiment, the serial communication signal is detected by the interface determination portion  124  in the large television lens  100  to switch the 36-pin interface changeover portion  121  and serial communication changeover portion  123 . However, the 36-pin interface changeover portion  121  and serial communication changeover portion  123  may be manually switched. 
     In the second embodiment, the interface determination portion  124  in the large television lens  100  detects the serial communication signal to switch the 36-pin interface changeover portion  121  and serial communication changeover portion  123 . However, these operations may be performed on the portable television lens  200  side. 
     As has been described above, a means for determining whether the interface of the camera is a parallel or serial interface, a means for determining whether the serial interface is a 12-pin or 36-pin serial interface, and interface changeover means are arranged in the large television lens. 
     Any connection errors of the serial and parallel interfaces in connection of the serial interface compatible large television lens to the portable television camera can be eliminated.