Patent Publication Number: US-2015070760-A1

Title: Lens apparatus and image pickup system including the lens apparatus

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a lens apparatus and an image pickup system including the lens apparatus, and particularly, to an operation of a plurality of image pickup systems such as in stereography. 
     2. Description of the Related Art 
     Conventionally, there is a known stereography system in which a plurality of image pickup systems where each of the plurality of image pickup systems can be used singularly are used to perform stereography. Meanwhile, in the stereography, just a slight displacement between left and right images may give the viewer not only a feeling of strangeness, but also a feeling of discomfort and fatigue. Therefore, in the stereography system, positions of corresponding optical elements that can be driven in the respective image pickup systems always need to be equalized between the plurality of image pickup systems. In a conventional system, the following technique is known as a method of always equalizing the positions of the corresponding optical elements that can be driven in the respective plurality of image pickup systems. 
     For example, Japanese Patent Application Laid-Open No. H09-127400 discloses a drive apparatus in which one of two zoom lenses is set to a master side, the other is set to a slave side, and the lens on the slave side is driven in accordance with the movement of the lens on the master side. 
     Japanese Patent Application Laid-Open No. 2008-154073 discloses an image pickup system that can match the settings of a plurality of image pickup apparatuses. According to the proposal, settings are changed in synchronization with the timing of changing the setting by another image pickup apparatus. Therefore, the settings of the image pickup apparatuses can be appropriately changed during the operation of the plurality of image pickup apparatuses. 
     However, the prior art disclosed in Japanese Patent Application Laid-Open No. H09-127400 does not particularly describe controls other than the control for causing the lens on the slave side to follow the lens on the master side, and particularly, does not describe a case in which there is a control from an automatic drive function included in the image pickup system. Furthermore, the lens on the slave side cannot follow due to functions set in the image pickup system on the slave side, and this is not taken into account. 
     In fact, if a function of limiting the drive range or the maximum speed is enabled in the image pickup system on the slave side, the lens on the slave side cannot completely follow the movement of the lens on the master side. 
     If setting information related to the functions of the image pickup systems is synchronized in the prior art disclosed in Japanese Patent Application Laid-Open No. 2008-154073, the image pickup system on the master side and the image pickup system on the slave side have the same settings. More specifically, separate settings are necessary for optimal settings of the image pickup systems. 
     SUMMARY OF THE INVENTION 
     An object of the present invention is to provide an image pickup system that can be operated singularly, in which switch to optimal settings is possible both in an image pickup system on a master side and an image pickup system on a slave side in an operation as a stereography system. 
     To attain the object, the present invention provides a lens apparatus including optical elements that can be driven in accordance with control commands from a plurality of control sources, the lens apparatus including: a mode switching unit configured to switch between a single mode in which the lens apparatus is used singularly and a plural mode in which the lens apparatus is used plurally; a communication unit configured to communicate with an external device; a driving state setting unit configured to set all of the optical elements to a first driving state in the single mode and set each of the optical elements to one of a second driving state and a third driving state in the plural mode; a driving state identification unit configured to identify the driving state set to each of the optical elements; a control source information output unit configured to output, for each driving state of each of the optical elements, control source information for determining a control command to be followed to drive the optical element among control commands from the plurality of control sources; and a command determination unit configured to determine a command for controlling drive of the optical elements based on the control source information determined by the control source information output unit, wherein in the second driving state, control commands for corresponding optical elements are output to other lens apparatuses through the communication unit, and in the third driving state, the control source information output unit outputs control source information different from the control source information in the first driving state and the second driving state. 
     According to the present invention, an image pickup system that can be operated singularly can be provided, in which switch to optimal settings is possible both in an image pickup system on a master side and an image pickup system on a slave side in an operation as a stereography system. 
     Further features of the present invention will become apparent from the following description of exemplary embodiments with reference to the attached drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a configuration block diagram of a first embodiment. 
         FIG. 2  is a diagram illustrating configurations in lens apparatuses and flows of commands. 
         FIG. 3  is a diagram illustrating an operation of an AF function when a priority table 1 is used. 
         FIG. 4  is a diagram illustrating an operation of the AF function when a priority table 2 is used. 
         FIG. 5  is a flow chart of the first embodiment. 
         FIG. 6  is a configuration block diagram of a second embodiment. 
         FIG. 7  is a flow chart of a process of disabling a function according to the second embodiment. 
         FIG. 8  is a flow chart of a process of not permitting a change in the setting according to the second embodiment. 
         FIG. 9  is a configuration block diagram of a third embodiment. 
         FIGS. 10A ,  10 B and  10 C are diagrams illustrating an advantageous effect in the third embodiment. 
         FIG. 11  is a flow chart of the third embodiment. 
         FIG. 12  is a configuration image diagram of an image pickup system including one master apparatus and a plurality of slave apparatuses. 
         FIG. 13  is a configuration image diagram of an image pickup system connecting one master apparatus and a plurality of slave apparatuses in series. 
     
    
    
     DESCRIPTION OF THE EMBODIMENTS 
     Hereinafter, exemplary embodiments of the present invention will be described in detail based on the attached drawings. 
     First Embodiment 
       FIG. 1  is a configuration block diagram of an image pickup system according to a first embodiment of the present invention. 
     The image pickup system of the present invention includes a lens apparatus A 10  and a lens apparatus B 11  with the same configuration. The lens apparatuses are operated in an operation mode which is one of a stand-alone operation mode (single mode) for stand-alone operation and a 3D synchronized operation mode (plural mode) for connecting the lens apparatuses for mutual communications to perform a synchronized operation of optical elements. 
     In the 3D synchronized operation mode, the optical elements included in the lens apparatuses are set to master (second driving state) or slave (third driving state) in the drive. The lens apparatus including the optical element in the master driving state outputs, to the other lens apparatus, an operation command for synchronized drive of the optimal unit. The lens apparatus including the optical element in the slave driving state drives the optical element based on the operation command of the optical element from the other lens apparatus. In the lens apparatuses in the stand-alone operation mode, all optical elements are driven in a single driving state (first driving state) in which synchronized drive with the optical elements of the other lens apparatus is not performed. 
     As illustrated in Table 1, one of the stand-alone operation mode and the 3D synchronized operation mode is set for the operation mode of each lens apparatus, and one of the stand-alone drive state, the master drive state, and the slave drive state is set as the driving state of each optical element included in the lens apparatus. 
     
       
         
           
               
               
               
             
               
                 TABLE 1 
               
             
            
               
                   
               
               
                 Operation Mode 
                 Stand-Alone 
                 3D Synchronized Operation Mode 
               
            
           
           
               
               
               
               
               
            
               
                   
                 Optical 
                 Operation Mode 
                   
                 Lens 
               
               
                   
                 element 
                 Lens Apparatus X 
                 Lens Apparatus Y 
                 Apparatus Z 
               
               
                   
                   
               
            
           
           
               
               
               
               
               
            
               
                 Driving 
                 Focus 
                 Stand-Alone 
                 Master Drive State 
                 Slave Drive 
               
               
                 State 
                   
                 Drive State 
                   
                 State 
               
               
                   
                 Zoom 
                 Stand-Alone 
                 Slave Drive State 
                 Master Drive 
               
               
                   
                   
                 Drive State 
                   
                 State 
               
               
                   
                 Iris 
                 Stand-Alone 
                 Master Drive State 
                 Slave Drive 
               
               
                   
                   
                 Drive State 
                   
                 State 
               
               
                   
                 . . . 
                 . . . 
                 . . . 
                 . . . 
               
               
                   
               
            
           
         
       
     
     The block diagram of  FIG. 1  will be described. 
     Hereinafter, an embodiment when the optical element is a focus lens will be described. 
     A focus operation unit A 12  provides a focus operation command to the lens apparatus A 10 , and a focus operation unit B 13  provides a focus operation command to the lens apparatus B 11 . 
     An image pickup apparatus A 14  and an image pickup apparatus B 15 , such as cameras, are connected to the lens apparatus A 10  and the lens apparatus B 11 , respectively. 
     An internal configuration of the lens apparatus A 10  will be described. 
     The lens apparatus A 10  includes a focus lens  1002  as an optical element, and a motor  1005  drives the focus lens  1002  forward and backward in an optical axis direction. A position detector  1003  detects the position of the focus lens  1002 . A driving controller  1004  calculates an amount of drive of the motor  1005  based on a driving command from a driving command determination unit  1012  described later and a position signal from the position detector  1003 . The driving controller  1004  outputs a drive current corresponding to the amount of drive to the motor  1005 . 
     The focus lens  1002 , the motor  1005 , the position detector  1003 , and the driving controller  1004  constitute a driving mechanism  1001 . 
     An operation mode setting unit  1007  (mode switching unit) is a unit that sets the operation mode of the lens apparatus A 10  to the stand-alone operation mode or the 3D synchronized operation mode and is constituted by a user interface unit including, for example, a switch or a switch and a display. A master/slave setting unit  1008  (driving state setting unit) is a unit that sets the driving state of one of the master drive state and the slave drive state for each optical element in the lens apparatus and is constituted by a user interface unit including, for example, a switch and a display. 
     A driving state identification unit  1009  is a unit that identifies which mode the driving state of each optical element is set, stand-alone drive state, master drive state, or slave drive state. If the operation mode setting unit  1007  sets the stand-alone operation mode, the driving state identification unit  1009  identifies that the stand-alone drive state is set to all optical elements. If the operation mode setting unit  1007  sets the 3D synchronized operation mode, the driving state identification unit  1009  identifies that the master drive state is set if the master/slave setting unit  1008  sets the optical element (focus lens here) to the master drive state and identifies that the slave drive state is set if the master/slave setting unit  1008  sets the optical element to the slave drive state. The driving state identification unit  1009  also identifies whether the lens apparatus is set to the stand-alone operation mode or the 3D synchronized operation mode based on the setting by the operation mode setting unit  1007 . 
     In accordance with the driving state, a control source information output unit  1014  determines control source information related to which control command the optical element is to follow to be driven and outputs the information to the driving command determination unit  1012 . A method of determining the control source information will be described later. 
     The lens apparatus A 10  communicates with external devices, such as the focus operation unit A 12 , the image pickup apparatus A 14 , and the lens apparatus B 11 , through a communication unit  1006 . A focus operation mechanism  1010  included in the lens apparatus A 10  is a mechanism for operating the focus and has a configuration such as a focus knob. An AF function controller  1011  generates an operation command of the focus lens  1002  based on an automatic focusing function (hereinafter, “AF function”). 
     The driving command determination unit  1012  is a unit that converts an operation command from the outside of the lens apparatus A 10  or from the inside of the lens apparatus A 10  to a driving command for driving the focus lens  1002  based on the control source information. Examples of the operation commands from the outside include operation commands from the focus operation unit A 12 , the image pickup apparatus A 14 , the lens apparatus B 11 , and controllers such as a PC and other demands. The driving command determination unit  1012  receives the operation commands through the communication unit  1006 . Examples of the operation commands from the inside include an operation command from the focus operation mechanism  1010  and an operation command from a function, such as the AF function controller  1011 , included in the lens apparatus that automatically drives the focus lens  1002 . 
     An operation command generation unit  1013  generates, in the 3D synchronized operation mode, an operation command for synchronizing and controlling the focus lens of another lens apparatus and outputs the operation command to the other lens apparatus. Information of the driving command of the focus lens included in the driving controller  1004  and position information of the present focus lens  1002  detected by the position detector  1003  are used to generate the operation command. 
       FIG. 2  will be used to describe flows of operation commands of two lens apparatuses in the 3D synchronized operation mode in relation to actual movements in the operation mode and the driving state. Although the lens apparatuses of  FIG. 2  have the same configurations as the lens apparatuses of  FIG. 1 , the configurations are simplified for the description. A lens apparatus Y and a lens apparatus Z are connected through a relay cable, and the driving state illustrated in Table 1 is set. In relation to the focus lens, the lens apparatus Y is set to the master, and the lens apparatus Z is set to the slave. In relation to the zoom lens, the lens apparatus Y is set to the slave, and the lens apparatus Z is set to the master. Although the focus lens and the zoom lens will be described, the same applies to the other optical elements. 
     The focus operation unit  12  first outputs a focus operation command. 
     When the focus operation command is input to the lens apparatus Y, the focus operation command is transmitted to a driving command determination unit  1012 Y through a communication unit  1006 Y. The driving command determination unit  1012 Y determines a driving command based on the received operation command and transmits the driving command to a focus driving mechanism  1001 Y. 
     The focus driving mechanism  1001 Y calculates the actual amount of drive and drives the focus lens based on the driving command. Since the focus lens of the lens apparatus Y is in the master driving state, an operation command generation unit  1013 Y generates an operation command for synchronizing and controlling the other lens apparatus and outputs the operation command to the communication unit  1006 Y. The information of the driving command and the position information of the focus lens from the focus driving mechanism  1001 Y are used to generate the operation command. 
     The lens apparatus Y and the lens apparatus Z perform synchronized operations through the relay cable. Therefore, the communication unit  1006 Y of the lens apparatus Y outputs the operation command output from the operation command generation unit  1013 Y, and the operation command is input to a communication unit  1006 Z of the lens apparatus Z through the relay cable between the lens apparatuses. When the focus operation command is input to the lens apparatus Z, the focus operation command is transmitted to a driving command determination unit  1012 Z through the communication unit  1006 Z. The driving command determination unit  1012 Z determines a driving command based on the received operation command and transmits the operation command to a focus driving mechanism  1001 Z. The focus driving mechanism  1001 Z calculates the actual amount of drive and drives the focus lens based on the driving command. 
     Similarly, a zoom operation unit  33  outputs a zoom operation command. 
     When the zoom operation command is input to the lens apparatus Z, the zoom operation command is transmitted to a driving command determination unit  3012 Z through the communication unit  1006 Z. The driving command determination unit  3012 Z determines a driving command based on the received operation command and transmits the driving command to a zoom driving mechanism  3001 Z. The zoom driving mechanism  3001 Z calculates the actual amount of drive and drives the zoom lens based on the driving command. The zoom lens of the lens apparatus Z is in the master driving state. Therefore, an operation command generation unit  3013 Z generates an operation command for synchronizing and controlling the other lens apparatus and outputs the operation command to the communication unit  1006 Z. The information of the driving command and the position information of the zoom lens from the zoom driving mechanism  3001 Z are used to generate the operation command. 
     The lens apparatus Y and the lens apparatus Z perform synchronized operations through the relay cable. Therefore, the communication unit  1006 Z of the lens apparatus Z outputs the operation command output from the operation command generation unit  3013 Z, and the operation command is input to the communication unit  1006 Y of the lens apparatus Y through the relay cable between the lens apparatuses. When the zoom operation command is input to the lens apparatus Y, the zoom operation command is transmitted to a driving command determination unit  3012 Y through the communication unit  1006 Y. The driving command determination unit  3012 Y determines a driving command based on the received operation command and transmits the driving command to a zoom driving mechanism  3001 Y. The zoom driving mechanism  3001 Y calculates the actual amount of drive and drives the zoom lens based on the driving command. 
     A method of determining the control source information by the driving command determination unit  1012  will be described. In the present embodiment, the control source information is a priority table of the operation commands of the control sources. Among the presently enabled operation commands of the control sources, the driving command determination unit  1012  preferentially selects an operation command with a high priority as a driving command, in accordance with the priorities defined in the priority table. 
     Table 2 illustrates the priority table indicating the priority order in the stand-alone drive state, the master drive state, and the slave drive state. 
     
       
         
           
               
               
               
             
               
                   
                 TABLE 2 
               
             
            
               
                   
                   
               
               
                   
                 Driving State 
                   
               
            
           
           
               
               
               
            
               
                 Priority 
                 Single or Master 
                 Slave 
               
               
                 Order 
                 Drive State 
                 Drive State 
               
               
                   
               
               
                 High 
                 Camera 
                 Other Lens 
               
               
                 ↑ 
                 Demand 
                 Camera 
               
               
                 ↓ 
                 AF Function 
                 Demand 
               
               
                 Low 
                   
                 AF Function 
               
               
                   
               
            
           
         
       
     
     The priority orders in the stand-alone drive state and the master drive state are the same. The priorities of the operation commands from the other lens apparatus can be lowered to drive the lens apparatus based on operations from the camera, the demand, and the AF function. In the slave drive state, the highest priority can be provided to the operation commands from the other lens apparatus to drive the lens apparatus by prioritizing the operation commands from the other (focus lens is set to the master) lens apparatus over the operations based on the camera, the demand, and the AF function of the lens apparatus in which the focus lens is set to the slave. In this way, the focus lens of the lens apparatus driven in slave can be driven in synchronization with the focus lens of the lens apparatus driven in master. 
       FIG. 3  is a diagram illustrating a movement of the focus lens  1002  illustrated in  FIG. 1  in the 3D synchronized operation mode during the execution of AF. A position p denotes a position of the focus lens  1002  of the lens apparatus in which the focus is set to the master drive state, and the lens apparatus of the master drive outputs, to the other lens apparatus, an operation command for driving the focus lens to the position p. An image pickup surface q denotes an image pickup surface of the image pickup apparatus connected to the lens apparatus in which the focus lens is set to the master drive state, and an image pickup surface r denotes an image pickup surface of the image pickup apparatus connected to the lens apparatus in which the focus lens is set to the slave drive state. (a) in  FIG. 3  illustrates a state of the focus lens in the lens apparatus in which the focus is set to the master drive state. (b) in  FIG. 3  illustrates a state of the focus lens of the lens apparatus in which the focus is set to the slave drive state, and the priority of the operation command from the AF function is higher than the priority of the operation command from the other lens apparatus (case of the priority order of the driving command for the same focus as in the stand-alone drive state (master drive state)). (c) in  FIG. 3  illustrates a state of the focus lens of the lens apparatus in which the focus is set to the slave drive state, and the priority of the operation command from the AF function is lower than the operation command from the other lens apparatus, as in the present embodiment. 
     When the priority of the operation command from the AF function in the lens apparatus in which the focus is set to the slave drive state is higher than the priority of the operation command from the other lens apparatus, the focus lens of the lens apparatus driven in slave is driven to a position different from the position p as illustrated in (b) in  FIG. 3  if the objects detected by the AF functions of the respective lens apparatuses are different. Therefore, the priority of the command from the AF function of the lens can be set lower than the priority of the operation command from the other lens apparatus to drive, the focus lens of the lens apparatus in which the focus is set to the slave is driven to the position p as illustrated in (c) in  FIG. 3 . 
     This allows synchronized drive of the focus lenses of the master drive state and the slave drive state. 
     
       
         
           
               
               
             
               
                 TABLE 3 
               
               
                   
               
               
                 Priority Order 
                 Slave Drive State 
               
               
                   
               
             
            
               
                 High 
                 Other Lens: Operation Command 
               
               
                   
                 AF: AF Within Predetermined Range From 
               
               
                   
                 Command Position 
               
               
                 ↑ 
                 Other Lens: Termination Command 
               
               
                   
                 Camera 
               
               
                 ↓ 
                 Demand: Operation Command 
               
               
                   
                 AF: Normal AF 
               
               
                 Low 
                 Demand: Termination Command 
               
               
                   
               
            
           
         
       
     
     Table 3 illustrates a priority table that allows the AF functions to locate the focus positions on the image pickup surfaces of the image pickup apparatuses connected to the lens apparatuses. 
     The table is characterized in that the priority of the “operation command from the AF function within a predetermined range n from the present command position” is set higher than the priority of the “termination command of the other lens apparatus”. The range n will be described later. The operation command denotes a command when the difference between an indicated value of the command signal and the present position of the movable portion of the lens apparatus is greater than a predetermined value. The termination command denotes a command when the difference between the indicated value of the command signal and the current position is zero or within a predetermined range. 
     A method of using the priority table to allow the AF functions to locate the focus positions to the image pickup surfaces of the image pickup apparatuses connected to the lens apparatuses will be described with reference to  FIG. 4 . The focus lens  1002 , the position p, the image pickup surface q of the image pickup apparatus connected with the lens apparatus in which the focus is set to the master, the image pickup surface r of the image pickup apparatus connected with the lens apparatus in which the focus is set to the slave, and the state (a) of the drive position of the focus lens of the lens apparatus in which the focus is set to the master are the same as in  FIG. 3 . In general, there is a case where the positions of the image pickup surface q and the image pickup surface r are displace from each other due to variations in manufacturing errors of the lens apparatuses and the image pickup apparatuses, and  FIG. 4  illustrates a displacement m of the image pickup surfaces. The range n is a drive range of the focus lens where the priority provided to the operation command from the AF function is high in the lens apparatus in which the focus is set to the slave. The range n is a drive range of the focus lens of the lens apparatus in which the focus around the position p (position of the focus operation command from the lens apparatus in which the focus is the master) is the slave, and the range n has a width that can absorb the displacement m of the image pickup surface. For example, n can be obtained by calculating the amount of the maximum displacement of the image pickup surface. The function selects an object to be focused within the range n to drive the focus lens  1002 . 
     (b) and (c) in  FIG. 4  illustrate a state of the focus lens of the lens apparatus in which the focus is the slave under the condition in which there is the displacement m of the image pickup surfaces between the image pickup surface q and the image pickup surface r. As in (c) in  FIG. 3 , (b) in  FIG. 4  illustrates a state of the focus lens when the priority of the operation command from the AF function is lower than the operation command from the other lens apparatus. The priority table used here is the table illustrated in Table 2. (c) in  FIG. 4  illustrates a state of the focus lens when the priority of the operation command from the AF function within the predetermined range from the present command position is higher than the termination command of the other lens apparatus. The priority table used here is the table illustrated in Table 3. (b) in  FIG. 4 , although the focus lenses  1002  of the lens apparatuses can be driven to the same position, the focus is slightly displaced due to, for example, the displacement of the positions of the image pickup surfaces of the lens apparatuses. Meanwhile, the priority table of Table 3 can be used to set the priority higher than the termination command of the other lens apparatus only in the focus drive through the AF function within the predetermined range n from the present command position (position p) among the operation commands of AF as illustrated in (c) in  FIG. 4 . As a result, the displacement of the focus due to the displacement of the image pickup surfaces can be compensated. 
     In this way, highly accurate AF can be performed without losing the synchronized drive of the master and the slave. 
     In the configuration of  FIG. 1 , the drive of the focus lens  1002  is processed in accordance with a processing flow illustrated in  FIG. 5 . 
     The process is started in step S 100 . In step S 101 , the driving state identification unit  1009  identifies whether the mode is the 3D synchronized operation mode. If the mode is the stand-alone operation mode, the process proceeds to step S 102 . If the mode is the 3D synchronized operation mode, the process proceeds to step S 103 . In step S 102 , the control source information output unit  1014  outputs the priority table for single driving state as the control source information, and the driving command determination unit  1012  determines the driving command based on the information. The process proceeds to step S 107 . 
     Meanwhile, in step S 103 , the driving state identification unit  1009  identifies whether the focus is in the slave driving state. If the focus is in the master driving state, the process proceeds to step S 104 . If the focus is in the slave driving state, the process proceeds to step S 106 . In step S 104 , the control source information output unit  1014  outputs the priority table for master driving state as the control source information, and the driving command determination unit  1012  determines the driving command based on the information. The process proceeds to step S 105 . In step S 105 , the operation command generation unit  1013  generates and outputs an operation command to be transmitted to the other lens apparatus. The process proceeds to step S 107 . 
     In step S 106 , the control source information output unit  1014  outputs the priority table for slave driving state as the control source information, and the driving command determination unit  1012  determines the driving command based on the information. The process proceeds to step S 107 . In step S 107 , the driving mechanism  1001  drives the focus lens  1002  in accordance with the driving command, and the process is finished. 
     As described, if the focus lens is in the slave driving state, the priority table is switched to raise the priority of the operation command from the other lens apparatus. This can prevent a situation in which only the focus lens  1002  in the slave driving state is driven in accordance with the operation command from an apparatus other than the other lens apparatus, and the movements of two lens apparatuses are different. 
     Although two types of priority tables are used in the embodiment, a priority switching unit not illustrated may be arranged to set the priority of the operation commands from part of the control sources higher than the priority of the other lens apparatus in the slave driving state. 
     The same function can be realized using a method of disabling the operation command from a specific control source in one priority table if the state is determined to be the slave driving state. For example, equivalent functions are used in the stand-alone/master drive state and the slave drive state as in a priority table illustrated in Table 4. In the slave drive state, a command from the camera, an operation command from the demand, a termination command from the demand, and an operation command from the normal AF, i.e. control commands other than the control commands from the other lens apparatus, are disabled to drive the focus lens based on the driving commands in different priority orders while basically using the same priority table. 
     
       
         
           
               
               
               
             
               
                 TABLE 4 
               
               
                   
               
               
                   
                 Stand-Alone/Master 
                 Slave 
               
               
                 Priority Order 
                 Drive State 
                 Drive state 
               
               
                   
               
             
            
               
                 High 
                 Camera 
                 &lt;Disabled&gt; 
               
               
                   
                 Demand: Operation 
                 &lt;Disabled&gt; 
               
               
                   
                 Command 
               
               
                 ↑ 
                 Other Lens: Operation 
                 Other Lens: 
               
               
                   
                 Command 
                 Operation Command 
               
               
                   
                 AF: Normal AF 
                 AF: Normal AF 
               
               
                 ↓ 
                 AF: AF Within 
                 AF: AF Within 
               
               
                   
                 Predetermined Range 
                 Predetermined Range 
               
               
                   
                 From Command Position 
                 From Command 
               
               
                   
                   
                 Position 
               
               
                   
                 Demand: Termination 
                 &lt;Disabled&gt; 
               
               
                   
                 Command 
               
               
                 Low 
                 Other Lens: 
                 Other Lens: 
               
               
                   
                 Termination Command 
                 Termination Command 
               
               
                   
               
            
           
         
       
     
     As a result, the highest three in the priority table of Table 3 remain in the slave drive state of Table 4, and an equivalent function as the embodiment can be realized. The setting allows processing a desired driving command with just one priority table. Although the driving command from the other lens apparatus is in the list of the priority order in the stand-alone drive state and the master drive state as illustrated in Table 4, the driving command is not input from the other lens apparatus, and the lens apparatus is not driven in accordance with the driving command from the other lens apparatus. Therefore, the driving command can be processed in accordance with a desired priority order in the stand-alone drive state and the master drive state even if “Other Lens: Operation Command” and “Other Lens: Termination Command” are disabled. 
     If a changing unit of the setting information related to the control sources is included, changes in the setting information of the disabled control sources may not be permitted. In an example of the AF function as a control source, the setting information may include setting of enable/disable and setting of the driving method, and the changing unit may include a switch. As illustrated in Table 4, changes in the setting information are not permitted when the AF function is disabled in the slave drive state. Details will be described in a second embodiment. 
     Second Embodiment 
       FIG. 6  is a configuration block diagram of the second embodiment of the present invention. The image pickup system of the present embodiment includes a lens apparatus A 20  and a lens apparatus B 21  with the same configuration therebetween. The configuration as a camera system is the same as in the first embodiment, and the same constituent elements as in  FIG. 1  are designated with the same reference numerals. 
     The difference in the image pickup system of the present embodiment from the configuration of the system of the first embodiment is that the control source information output unit  1014  is not included, the focus operation mechanism  1010  is not included, and an AF function set value setting unit  2015  that sets enable/disable of the AF function and an operation method is included. The AF function set value setting unit  2015  is constituted by a user interface including, for example, a switch or a switch and a display. 
     An AF function controller  2011  uses one or both of a phase difference signal and a video signal to generate an operation command only if the AF function is enabled and the drive is not the slave drive state in the setting of the AF function set value setting unit  2015 . A driving command determination unit  2012  converts an operation command from the outside or the inside to a driving command inside the lens apparatus. 
     In the present embodiment, the method of determining the driving command in the driving command determination unit  2012  is the same as in the conventional lens apparatus with the stand-alone operation of the lens apparatus. Therefore, the description will be skipped. 
     In the configuration of  FIG. 6 , enable/disable of AF is set in accordance with a processing flow illustrated in  FIG. 7 . The processing flow is started when the power is turned on or when the driving state identification unit  1009  identifies a change in the driving state. 
     The process is started in step S 200  and proceeds to step S 201 . 
     In step S 201 , the driving state identification unit  1009  identifies whether the mode is the 3D synchronized operation mode. If the mode is the stand-alone operation mode, the process proceeds to step S 203 . If the mode is the 3D synchronized operation mode, the process proceeds to step S 202 . In step S 202 , the driving state identification unit  1009  identifies whether the focus is in the slave driving state. If the focus is the master, the process proceeds to step S 203 . If the focus is the slave, the process proceeds to step S 204 . 
     In step S 203 , the AF function controller  2011  sets the enable/disable of the AF function to the set value set in the AF function controller to allow using the AF function as in the conventional technique, and the process is finished. 
     In step S 204 , the AF function controller  2011  disables the AF function regardless of the set value set in the AF function. 
     As a result, the AF function is disabled in the slave, and the operation command is not input from the AF function to the driving command determination unit  2012 . Disabling of the AF function is expected to reduce the power consumption inside the lens apparatus and to reduce the load of the CPU. 
     In the configuration of  FIG. 6 , the setting of the AF function is changed in accordance with a processing flow illustrated in  FIG. 8 . The process is started in step S 210  and proceeds to step S 211 . 
     In step S 211 , the AF function set value setting unit  2015  changes the setting related to the AF function, and the process proceeds to step S 212 . In step S 212 , the driving state identification unit  1009  identifies whether the mode is the 3D synchronized operation mode. If the mode is the stand-alone operation mode, the process proceeds to step S 214 . If the mode is the 3D synchronized operation mode, the process proceeds to step S 213 . In step S 213 , the driving state identification unit  1009  identifies whether the focus lens is the slave. If the focus is the master, the process proceeds to step S 214 . If the focus lens is the slave, the process proceeds to step S 215 . 
     In step S 214 , the set value set by the AF function set value setting unit  2015  is reflected on the AF function controller  2011 , and the process is finished. In step S 215 , the set value set by the AF function set value setting unit  2015  is not reflected on the AF function controller  2011 , and the process is finished. 
     The fact that the set value is not reflected may be reported to the AF function set value setting unit  2015 , and a message indicating that the setting is not possible may be output to the user. 
     In this way, it is possible not to reflect the setting on the slave lens apparatus in the focus even if there is an attempt to change the setting of the enable/disable of AF or the operation method. In the present embodiment, the setting is not reflected on the slave lens apparatus even if there is an attempt to change the setting of the enable/disable of AF or the operation method. However, when there is an attempt to change the set value in the slave lens apparatus, the information related to the setting change may be transmitted to the master lens apparatus, and the change in the setting in the slave lens apparatus may be reflected on the master lens apparatus. Consequently, the slave lens apparatus follows the drive of the master lens apparatus in which the change in the setting is reflected. Therefore, the change in the setting is reflected on the drive of the 3D system. Although an example of the AF is illustrated as a function for driving the focus lens, another example includes an automatic reproduction function for automatically reproducing the drive. 
     Although an example of the AF function as a function for disabling when the focus lens is the slave is illustrated in the present embodiment, other examples include the automatic reproduction function and a focus operation function not illustrated included in the lens apparatus. A focus operation command communication function as part of a function of communicating with the focus operation unit A 12  and of a function of communicating with the image pickup apparatus or with a PC not illustrated can also be disabled. An advantageous effect of reducing the load of the communication can be expected by disabling the part of the communication function. 
     Third Embodiment 
       FIG. 9  is a configuration block diagram of a third embodiment of the present invention. The image pickup system of the present embodiment includes a lens apparatus A 30  and a lens apparatus B 31  with the same configuration, and the same constituent elements as in  FIG. 1  or  6  are designated with the same reference numerals. 
     Zoom operation units  32  and  33  provide zoom operation commands to the lens apparatus A 30  and the lens apparatus B 31 , respectively. A tracking set value setting unit  3015  sets tracking information, such as enable/disable of a zoom tracking function and a tracking range, that can restrict the drive range of the zoom lens. A method of restricting the drive range of the zoom lens will be described later. 
     A motor  3005  moves and drives the zoom lens  3002  serving as an optical element in the optical axis direction. A position detector  3003  detects the position of the zoom lens  3002 . 
     A driving controller  3004  calculates an amount of drive of the motor  3005  based on a driving command from a driving command determination unit  3012  described later and a position signal from the position detector  3003  and outputs a drive current corresponding to the amount of drive to the motor  3005 . The driving controller  3004  has a function of limiting the drive range in accordance with the tracking information from the tracking set value setting unit  3015 . The zoom lens  3002 , the motor  3005 , the position detector  3003 , and the driving controller  3004  constitute a driving mechanism  3001 . 
     The driving command determination unit  3012  converts an operation command from the outside or inside to a driving command inside the lens apparatus. In the present embodiment, the method of determining the driving command in the driving command determination unit  3012  is the same as in the conventional lens apparatus with stand-alone operation. Therefore, the description will be skipped. 
     An operation command generation unit  3013  generates an operation command for synchronizing and controlling the zoom lens of the other lens apparatus and outputs the operation command to the other lens apparatus. The information of the driving command of the zoom lens  3002  included in the driving controller  3004  and the present position information of the zoom lens  3002  detected by the position detector  3003  are used to generate the operation command of the operation command generation unit  3013 . 
     An advantageous effect of the present embodiment will be described with reference to  FIGS. 10A to 10C . 
     A position P is a position of the zoom lens  3002  of the lens apparatus set to the master for the zoom lens, and the lens apparatus set to the master outputs an operation command to the other lens apparatus to drive the zoom lens to the position P. In  FIGS. 10A to 10C , S 11  and S 12  illustrate a wide-angle end and a telephoto end, respectively, as ends of the wide-angle side and the telephoto side of the zoom lens of the lens apparatus in which the zoom lens is set to the master. Similarly, S 21  and S 22  illustrate a wide-angle end and a telephoto end, respectively, of the zoom lens in the lens apparatus in which the zoom is set to the slave. T 11  and T 12  denote tracking ends of the wide-angle side and the telephoto side, respectively, in which the zoom lens is set to the master lens apparatus. If the tracking function is enabled, the zoom lens  3002  cannot be driven to the wide-angle side beyond T 11  and to the telephoto side beyond T 12 . Similarly, T 21  and T 22  denote tracking ends of the wide-angle side and the telephoto side in which the zoom lens is set to the slave lens apparatus. 
       FIG. 10A  illustrates a drive range R 1  of the zoom lens in the lens apparatus in which the zoom lens is the master. The tracking ends T 11  and T 12  are set, and the tracking function is enabled.  FIG. 10B  illustrates a drive range R 2  of the zoom lens in the lens apparatus in which the zoom lens is set to the slave as in the prior art. The tracking ends T 21  and T 22  are set, and the tracking function is enabled.  FIG. 10C  illustrates a drive range R 3  of the zoom lens in the lens apparatus in which the zoom lens is the slave, wherein the tracking ends T 21  and T 22  are set, and the tracking function is disabled as in the present embodiment. 
     In  FIG. 10B , since the tracking ends are set and the function is enabled as in the prior art, the zoom lens  3002  of the lens apparatus set to the slave in the zoom cannot be driven to the wide-angle side beyond T 21 . Therefore, the zoom lens  3002  cannot be driven to the position P and is terminated at the portion of the tracking end T 21 . Thus, as illustrated in  FIG. 10C , the tracking function can be disabled when the lens apparatus is determined to be the slave to drive the zoom lens  3002  to the position P. 
     In this way, the synchronized drive of the master and the slave is possible. 
     In the configuration of  FIG. 9 , a process of whether to adapt the tracking function to the driving command is executed in accordance with a processing flow illustrated in  FIG. 11 . 
     The process is started from step S 300  and proceeds to step S 308 . In step S 308 , the driving command determination unit  3012  determines the driving command, and the process proceeds to step S 101 . In step S 101 , the driving state identification unit  1009  identifies whether the mode is the 3D synchronized operation mode. If the mode is the stand-alone operation mode, the process proceeds to step S 302 . If the mode is the 3D synchronized operation mode, the process proceeds to step S 103 . In step S 302 , the driving controller  3004  restricts the driving command within the tracking range based on the tracking information set from the tracking set value setting unit  3015 , and the process proceeds to step S 107 . 
     Meanwhile, in step S 103 , the driving state identification unit  1009  identifies whether the focus lens is set to the slave. If the focus lens is set to the master, the process proceeds to step S 304 . If the focus lens is set to the slave, the process proceeds to step S 306 . In step S 304 , the driving controller  3004  restricts the driving command within the tracking range based on the tracking information set from the tracking set value setting unit  3015 , and the process proceeds to step S 105 . In step S 105 , the operation command generation unit  3013  generates and outputs an operation command to be transmitted to the other lens apparatus. The process proceeds to step S 107 . 
     In step S 306 , the function of the tracking set value setting unit  3015  is disabled, and the driving controller  3004  does not change the driving command. The process proceeds to step S 107 . 
     In step S 107 , the driving mechanism  3001  drives the zoom lens in accordance with the driving command, and the process is finished. 
     This can prevent a situation in which the drive range is limited, for the operation command from the other lens apparatus set to the master, by the zoom tracking function set to the slave lens apparatus, and the movements of two lens apparatuses are different. 
     As in the second embodiment, a change in the setting information related to tracking may not be permitted if the lens apparatus is set to the slave. 
     Examples of the function of limiting the range of the drive such as tracking include an F-Hold function in which a limit is set to the zoom position on the telephoto side to maintain predetermined brightness and an end adjustment function in which the portion of the drive end is adjusted. Similar advantageous effects can be obtained for a function of limiting the drive speed, such as a maximum speed limit and a minimum speed limit, and a function of limiting the gain of the drive, such as movement start characteristics and termination characteristics. 
     The present invention has been illustrated and described with the first, second and third embodiments. Derived forms of the embodiments of the present invention will be illustrated here. 
     The optical element is a focus lens or a zoom lens in the examples described in the first to third embodiments. Depending on the embodiment, the same advantageous effects can be obtained even if the focus lens and the zoom lens are replaced, an IE (extender) lens is inserted to and removed from an optical path, or the micro lens and the optical element are replaced by an iris mechanism, an IS mechanism (image stabilization mechanism and image stabilization function), or angle of convergence adjustment mechanism. Although the AF has been illustrated as an example of the function of automatically driving the focus lens, another example includes an automatic reproduction function. Examples of the function for automatically driving the zoom lens include an angle-of-field correction function and an automatic reproduction function (shot function for moving to a stored zoom position or a preset function of reproducing the stored movement of the zoom). Examples of the function of automatically driving the iris mechanism include iris correction and close detection. The iris correction and the close detection will be simply described here. 
     The iris correction function is a function of driving the iris to compensate the darkened brightness to compensate the light falloff due to an insertion of an extender lens. If the iris correction function is enabled and the extender lens is inserted, there is a problem that when a command equivalent to the close of the iris is input, the iris is driven to a position for correcting the brightness in response to the command equivalent to the close, and the iris is not closed. Thus, the close detection function is a function of closing the iris without performing the correction by the iris correction function if a command equivalent to the close is input to the iris. 
     Other than the setting from the operation mode setting unit  1007 , the driving state identification unit  1009  may use the fact of whether the communication unit  1006  is connected to the lens apparatus B 11  to identify whether the mode is the stand-alone operation mode or the 3D synchronized operation mode. Similarly, if the driving state identification unit  1009  identifies that the mode is the 3D synchronized operation mode, the driving state identification unit  1009  may automatically identify the slave driving state or the master driving state based on the driving state of the operation unit of the connected optical element or of other optical elements or based on the driving state of the lens apparatus B 11 . 
     Although the 3D synchronized imaging by two lens apparatuses has been illustrated this time as an example of the operation by a plurality of lens apparatuses, an operation on a multipoint image pickup system by two or more lens apparatuses is also possible. As illustrated in  FIG. 12 , an example of the method includes a multipoint imaging system in which one lens apparatus set to the master (lens apparatus M) and a plurality of lens apparatuses set to the slave (lens apparatuses S) are connected. According to the method, all slave lens apparatuses follow one master lens apparatus, and synchronized imaging is possible in all lens apparatuses. 
     As illustrated in  FIG. 13 , another example of the method includes a multipoint image pickup system in which one lens apparatus set to the master (lens apparatus M) is at the top, and a plurality of lens apparatuses (lens apparatuses R and lens apparatus S) are connected in series. In addition to the stand-alone operation mode, the master driving state, and the slave driving state, the method may include a synchronized relay operation mode for driving based on an operation command from another lens apparatus and issuing an operation command to yet another lens apparatus. In  FIG. 13 , in the lens apparatuses set to the synchronized relay operation mode (lens apparatuses R), the control source information output units execute similar processes as in the slave driving state, and the operation command generation units output, without a change, the received operation commands from other lens apparatuses. The lens apparatus at the end connected in series is the lens apparatus set to the slave (lens apparatus S). In this way, the lens apparatus of the present invention in the derived forms of the embodiments of the present invention can be applied to the multipoint image pickup system including a plurality of lens apparatuses connected in series with the master lens apparatus at the top. 
     Although the lens apparatus has been described in the embodiments, similar advantageous effects can be attained in an image pickup system including the lens apparatus. 
     Although the exemplary embodiments of the present invention have been described, the present invention is not limited to the embodiments, and various modifications and changes can be made within the scope of the present invention. 
     While the present invention has been described with reference to exemplary embodiments, it is to be understood that the invention is not limited to the disclosed exemplary embodiments. The scope of the following claims is to be accorded the broadest interpretation so as to encompass all such modifications and equivalent structures and functions. 
     This application claims the benefit of Japanese Patent Application No. 2011-077651, filed on Mar. 31, 2011, which is hereby incorporated by reference herein in its entirety.