JPH04273671A - Conversion adaptor in interchangeable lens system - Google Patents

Abstract

PURPOSE:To allow the conversion adaptor to use also a 2nd lens by decoding a control signal of a 1st signal form outputted from a camera main body, converting the signal into a control signal of a 2nd signal form and sending the converted signal to a 2nd lens unit. CONSTITUTION:A lens control signal sent from a camera via a video movie camera interchangeable lens electronic mount 2 by a serial communication block 7 is converted into a signal form suitable for controlling a still camera lens by a control data conversion block 11 and the result is sent to a serial communication block 8. The serial communication block 8 outputs the control data from the camera from a still camera interchangeable lens electronic mount 3 as a level control signal via a 2-way serial communication line 9 in a communication timing converted into a timing suitable for controlling the still camera lens from the communication timing from the camera by a timing conversion block 10.

Description

[Detailed description of the invention]

0001

[Industrial Application Field] The present invention is useful for connecting cameras and lenses of different standards to each other, such as when connecting interchangeable lenses of interchangeable lens systems for still cameras of different standards to an interchangeable lens type video camera device. This invention relates to a conversion adapter that enables various types of control.

[Background Art] In recent years, in video movie systems, an interchangeable lens system for movies that can be used interchangeably with various lenses has been proposed, unlike a normal camera/lens integrated system. By the way, speaking of interchangeable lens systems, systems for single-lens reflex cameras (systems for still cameras) are generally known. Various lenses for this system, including special lenses tailored to various uses, are already available on the market.

[0003] Since the video movie system is still in its introductory period and the market has not yet been developed, it is not realistic to produce a wide variety of special lenses that should be a feature of the interchangeable lens system in the early stages. . Therefore, there has been a demand to use interchangeable lenses for single-lens reflex cameras that have already been introduced in the market and are recognized by users.

[0004] Therefore, a conversion adapter is required to connect a video movie camera and a still camera lens. This conversion adapter is mainly used to (1) match the mounts of the video movie interchangeable lens system and the Stell camera interchangeable lens system since they are different; and (2) to match the imaging surfaces and mounts of the video movie camera and Stell camera. Adjusting the optical path difference due to the difference in distance from the position (3) Communication format specified for passing data to various types necessary for control in the video movie interchangeable lens system and the still camera interchangeable lens system This is necessary for three reasons: because the data formats/control formats are different, and because the data formats/control formats are different.

Among these reasons, (1) and (2) can be relatively solved simply by physical or optical design. However, regarding the reason (3), it is clear that the entire system will not operate normally if only the connection is made.

[0006] That is, there are considerable differences between video movies and still cameras in terms of their form, shooting conditions, functions, and other conditions. This difference in control will be explained below using the AF control method as an example.

First, an autofocus control system for a camera-integrated VTR will be explained below with reference to FIG.

Light from a subject (201) passes through a focusing lens unit (202), a zooming lens unit (203), and an aperture mechanism (204), and forms an image on an image sensor (101) on the camera side. . As a result, a television signal is generated and output by the camera signal processing circuit (102).

On the other hand, the output is passed through a high-pass filter (10
In step 3), only high-definition signals that are likely to be generated in large quantities during focusing are extracted, converted into digital signals by an A/D converter (104), and used as judgment information for an AF (Auto-focus) control judgment circuit (105). shall be. At this time, the position information of the focusing lens unit of the lens is obtained by the focus encoder (207), the position information of the zooming lens unit is obtained by the zoom encoder (210), and the information about the aperture amount is obtained by the iris encoder (213). It is used as a reference for judgment.

[0010] Furthermore, in order to determine the direction of blur, that is, the lens driving direction, the driver (1
07), actuators such as bimorph plates (10
8) to vibrate the image sensor (101) by a minute width before and after the focal plane. Based on this vibration, a determination circuit (207) determines whether it is a front pin or a rear pin. The judgment result is determined by the driver for the focusing lens unit on the lens side (
206), and the motor (205) moves the focusing lens unit (202) to the in-focus position.

Note that the zooming lens unit (203
) is the zooming lens unit driver (209)
, a motor (208), and an aperture mechanism (
204) is driven by an aperture mechanism driver (212) and an IG meter (211). Drive control signals are generated separately from the AF control circuit from the camera side, and include a zoom control signal (110) and an iris control signal (110).
109).

Next, a focus control method in an interchangeable lens type VTR will be explained below with reference to FIG. In FIG. 8, components having the same configuration as those in FIG. 7 are designated by the same numbers. Since the formation of the basic AF control signal is the same as that in FIG. 7, only the parts that are different from FIG. 7 will be explained.

The focus determination information and the focusing lens unit drive direction information are given to a camera microcomputer (105) having an AF control determination function. In the camera microcomputer (105), this AF information and the iris control signal (109) and zoom control signal (110) given from a circuit other than the AF control circuit are used to satisfy the compatibility of control of the interchangeable lens. The information is converted according to a predetermined format.

Regarding focus, this information conversion means, for example, normalizes the driving speed of the focus motor by "the rate of change of the diameter of the circle of confusion on the imaging surface when the aperture is open".

Furthermore, the camera microcomputer (105) transmits various data in parallel to reduce the number of data communication lines to the lens.
Serial conversion is performed and information is transmitted to the lens side via a bidirectional serial communication line (301). This serial communication is received by the lens microcomputer (214), and serial-to-parallel conversion is performed within the lens microcomputer, and depending on the content of each control signal, the driver for the focusing lens unit (206), the driver for the zooming lens unit (207), and the aperture mechanism are used. A drive signal is output to each driver (212), and the motor and IG meter are driven and controlled.

Furthermore, each encoder information, which is the position information of each unit, is once stored in the lens microcomputer (214).
The information is converted according to a predetermined format to satisfy the control compatibility of the interchangeable lens, and after parallel-to-serial conversion is performed, it is sent as data to the lens via the bidirectional serial communication line (301). The information is transmitted to the camera microcomputer (105). This position information is serial-parallel converted in the camera microcomputer (105) and used as determination information for AF focus determination and the like.

Finally, the focus control method in the still camera will be explained using FIG. 9. Subject (2)
The light from the focusing lens unit (20
2), the film surface (111) on the camera side via the zooming lens unit (203) and aperture mechanism (204)
imaged on top. The AF optical system independently samples two beams of light that have passed through different areas of the photographic lens, and uses a pair of secondary imaging lenses (112) integrated with a prism to focus them on the film surface (primary imaging surface/focus surface). The aerial image formed by the sensor (equivalent) is re-imaged on the surface of the AF distance measuring sensor (113).

The outputs of the AF distance measuring sensors (113) are respectively given to photometric ICs (114), and the photometric ICs (114)
14), the camera microcomputer (1) obtains subject brightness information from each AF ranging sensor and performs AF control.
05). The camera microcomputer (105) compares the information with the focusing reference interval based on the information on the two images to determine the amount of defocus. Once you know the amount of defocus, you can focus by moving the focusing lens unit so that it becomes zero.

However, since this amount of def focus is based on the focus plane of the camera, the actual distance ring rotation amount to absorb the optical defocus amount depends on the focal length of the lens used and the position of the distance ring at that time (the subject). (distance). The amount also varies depending on the focusing type of the lens used.

Therefore, in order to calculate accurate lens drive information in the camera microcomputer (105), lens extension/sensitivity coefficient, distance ring drive amount, maximum defocus amount, aperture F-No., focal length information, etc. are required from the lens side. It is necessary to obtain information specific to the lens.

The lens microcomputer (214) performs parallel-to-serial conversion of necessary specific data read from the lens specific information storage means (215...which may be stored as ROM information of the lens microcomputer). and a bidirectional serial communication line (3
01) to the camera side.

On the camera side, the serial data sent from the lens is serial-parallel converted and used to create AF control signals as necessary. Further, these data are transmitted according to a predetermined format in order to satisfy control compatibility of the interchangeable lenses.

[0023]

[Problems to be Solved by the Invention] As described above, the AF control method in the interchangeable lens system for video movies and the AF control method in the interchangeable lens system for still cameras have been proposed.
There are differences in control content and means from the F control method,
When considering the shooting environment, in the case of a still camera, the subject to be photographed is basically fixed, and in order not to miss a shot, both the focus and iris must be fast, and the focus position and optimal exposure condition must be fast. It is desired to reach the target quickly and without error. For this reason, the actuator (motor) used in still camera lenses is one that satisfies the above conditions, such as a pulse motor.

On the other hand, in the case of a video camera,
The subject to be photographed is temporally continuous, and it is desirable that the time to focus be short, but on the other hand, if you take into account cases where objects other than the subject to be photographed cross the subject, if the speed is too high, it will look strange when viewed as a continuous image. This may occur. Therefore, if anything, smoothness is required rather than high speed. For this reason, actuators used in video camera lenses are IG meters, DC motors (originally AC motors are desirable, but they are disadvantageous in terms of cost), and the like. Further, as described above, the lens information required for AF control is different, and the communication format is also different.

Therefore, the AF control data from the camera in the video movie interchangeable lens system is directly applied to the lens A in the still camera interchangeable lens system.
It is not possible to use it as F control data.

Therefore, as shown in (3) above,
It is desired to realize an adapter device that can convert the form of control information between a camera and a lens into a form that allows control of the lens.

[0027]

[Means for Solving the Problems] The present invention solves the above-mentioned problems and matches the AF control methods of cameras and lenses that have different control methods, so that, for example, a still camera can be replaced with a video movie interchangeable lens system. Enables the use of interchangeable lenses in the lens system and provides excellent AF
This was developed with the aim of providing a conversion lens type camera system that enables control, and its feature is that control information output from the camera body is transmitted to the first lens in the form of a first signal. In the interchangeable lens system, the second lens unit is controlled by control information in a second signal form different from the first signal form in the camera body. an adapter device capable of connecting the first
converting means for decoding control information in a signal form and converting it into a control signal in a second signal form; and converting control information converted into the second signal form by the converting means into a control signal in the second signal form. and means for communicating with the unit.

Another feature of the present invention is a control system that controls a first control object by communicating control information output from the control means to the first control object in a first signal form. An adapter device capable of connecting a second controlled object controlled by control information in a second signal format different from the first signal format to the control means, the adapter device configured to control the output from the control means. converting means for decoding control information in the first signal form and converting it into a control signal in the second signal form; and converting the control information converted into the second signal form by the converting means. and means for communicating with the second controlled object.

[0029]

[Operation] This enables control between control means and controlled means that have different control methods, and various controls between cameras and lenses, for example, in an interchangeable lens system.
For example, it is now possible to connect a still camera lens unit with a different AF method to a video camera, and when viewed from the video camera, the still camera interchangeable lens group can be treated as if it were a video movie interchangeable lens group. There is no need to be aware of group differences. Furthermore, the interchangeable lens group for a still camera can operate as if it were processing data from a still camera, and can be used as a lens group without any need for any changes.

[0030]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Specific embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a diagram schematically showing a conversion adapter device according to the present invention. In the figure, reference numeral 101 represents the entire conversion adapter device, and reference numeral 2 indicates the format defined in the video movie interchangeable lens system for connecting the conversion adapter device and the video movie of the video movie interchangeable lens system. The lens side terminal of the electronic mount is shown, and 3 is the camera side terminal of the electronic mount according to the format defined in the interchangeable lens system for still cameras, for connecting the conversion adapter and the lens of the interchangeable lens system for still cameras. 4 is an electrical control signal conversion circuit for absorbing the difference in format or control method between the two interchangeable lens systems and allowing the two systems to operate mutually without any problems, and 5 is the imaging control circuit for both systems. This indicates the physical distance for absorbing optical path differences between surfaces.

By using such a conversion adapter, a still camera lens can be connected to a video movie system, and the system can operate normally.

In an interchangeable lens system for a video movie camera, the object to be photographed between the camera and the lens is a "moving image", and the photographing conditions for the object generally change over time.

Specifically, for example, when trying to photograph a scene where a person is walking, the distance to the person changes from moment to moment, and the brightness also changes depending on the place the person passes.

[0035] In current video movie systems, AF (automatic focus control) and AE (automatic exposure control) are performed, and the contents of these controls change from moment to moment.

Regarding AF control, especially in interchangeable lens systems, a control method is used in which the amount of "blur" of the subject is determined from the video signal and the focus lens is driven so that the amount is minimized. .

[0037] When such control is performed, aperture position information and focal length information are required when performing AF calculations.

Another problem is that photography continues until the optimal subject conditions are set, and the process is also recorded on tape. Therefore, it is desirable that the control to the video movie camera system and the transmission of position information from the lens to the camera be performed simultaneously and independently and in real time. For this reason, electrical information in the video movie interchangeable lens system is transmitted by multi-byte serial communication. Since AF control is controlled based on image information, the timing of this serial communication is performed in synchronization with a vertical motive signal (generally referred to as a V synchronization signal) of a video signal.

On the other hand, in the camera/lens control in the still camera interchangeable lens system, the object to be controlled is a "still image", and the photographing conditions of the subject are almost fixed. Furthermore, as long as the shutter does not fall, the image will not be captured on the film, so it does not really matter how the subject image is captured between the time the shutter is pressed and the time the shutter falls.

For this reason, in the still camera system, no driving command is issued to the lens when the shutter is not pressed, and after the shutter is pressed, focus calculations and exposure calculations are performed and the lens is sequentially driven to achieve the optimum subject condition. Bye. For this reason, the exchange of electrical information in the interchangeable lens system for still cameras is performed by small-byte serial communication, and the timing of this communication can basically be such that communication begins only when the shutter button is pressed. It turns out.

As described above, there are differences in communications or differences in control methods based on differences in system design concepts due to differences in original subjects.

Furthermore, each lens to be controlled is provided with a drive circuit appropriate for its control method, and differences in control means due to differences in drive circuits and information on lens position and status (status) communicated to the camera. Differences in the encoders used to do this also pose a big problem.

FIG. 2 is a block diagram of a signal path in an interchangeable lens system including the conversion adapter device of the present invention. In the figure, numerals 2 to 4 have the same configuration as that in FIG. 1. Reference numeral 6 denotes a bidirectional serial communication line that connects the interchangeable lens electronic mount 2 for a video movie camera and the electrical control signal conversion circuit block 4, and is connected to the serial communication block 7 inside the electrical control signal conversion circuit block 4. There is. A bidirectional serial communication line 9 connects the still camera interchangeable lens electronic mount 3 and the electrical control signal conversion circuit block 4, and is connected to the serial communication block 8 inside the electrical control signal conversion circuit block 4. .

The lens control signal transmitted from the camera via the interchangeable lens electronic mount 2 for a video movie camera by the serial communication block 7 is converted into a form suitable for controlling the still camera lens by the control data exchange block 11. It is converted and transmitted to the serial communication block 8. The serial communication block 8 converts the timing of the communication from the camera into a timing suitable for controlling the still camera lens by the timing conversion block 10, and converts the control data from the camera into two-way serial communication. The signal is output from the still camera interchangeable lens electronic mount 3 via the line 9 as a signal for controlling the lens.

Status data such as positional information from the lens transmitted by the serial communication block 9 from the lens via the still camera interchangeable lens electronic mount 3 is transmitted to the status data exchange block 12 for use by the video movie camera. The data is converted into a format suitable for the data and transmitted to the serial communication block 6. In the serial communication block 7, information is transmitted to the camera side at a timing determined by a format or the like according to the communication timing from the camera.

As described above, by connecting different cameras and lenses of the system and converting data into the required format, appropriate control and operation as a total system can be achieved.

Next, using FIGS. 3 to 6, a detailed explanation will be given of the control operation when AF control is actually performed by communication of control information between the camera and the lens in the interchangeable lens system.

FIG. 3 is a block diagram showing a state in which a still camera lens is attached to a video movie camera using a conversion adapter in the interchangeable lens system of the present invention. In addition, in the figure, the same reference numerals are given to the parts having the same configuration as in the above-described example, and the explanation thereof will be omitted.

In the figure, the parts divided by the two dotted and chain lines are the camera side, the conversion adapter, and the lens side, respectively, from the right.

On the camera side, the control signal finally generated in the AF circuit is converted from parallel to serial by the camera microcomputer (105) in the same manner as shown in FIG. ) is sent to the conversion microcomputer (303) in the conversion adapter. The conversion microcomputer (303) performs serial-to-parallel conversion on the serial data sent from the camera and extracts AF control data. Furthermore, the conversion microcomputer (303) has data conversion means (304...R of the conversion microcomputer) as described later.
A data format in which a still camera lens can be used by using a calculation means (305... which may be stored as ROM information of a conversion microcomputer), or both. Convert to The converted data is converted from parallel to serial in the lens microcomputer (303) and sent as serial data to the lens side via the bidirectional serial communication line-B (302).

[0051] The lens microcomputer (214) converts serial data sent from the conversion adapter into parallel and converts it into a focusing lens unit driver (206).
The focusing lens unit (202) is driven through the lens. By taking such means, it becomes possible to drive the still camera lens and perform AF control based on the control signal generated by the AF control circuit of the video camera.

Next, the specific data conversion means (calculation means) carried out within the conversion microcomputer will be explained. As mentioned above, the AF control signal from the video camera side is normalized and sent to the DC motor in the form of "acceleration of change in the diameter of the circle of confusion on the imaging surface when the aperture is open" and "driving direction". It's coming.

On the other hand, A of the still camera lens
The F control signal must be sent in the form of "the number of driving pulses of the pulse motor inside the lens" and the "driving direction". Therefore, data must be converted within the conversion adapter based on the relationship between these two parties.

Here, from the lens side, as data specific to the lens, for example, the amount of focusing lens extension per pulse of the focusing pulse motor (FLK
), the focusing lens extension amount, and the defocus coefficient (DFC) are sent. It is also assumed that the lens-specific aperture F-No (F) is also sent.

In other words, the driving expression based on the AF control information from the video camera can be said to be driving at "velocity+direction". Incidentally, a pulse motor is usually used as a driving means built into a lens for a still camera because of its high-speed response, but a pulse motor cannot accurately take the form of "speed". As mentioned above, the pulse motor has a meaning in driving one pulse, but the time required for driving one pulse cannot be obtained from a still camera lens.

That is, the required specification for a still camera is high speed, and the speed changes depending on the performance of the lens. Therefore, to consider speed control with a still camera, the form of speed must be created using a pseudo method.

Therefore, in the present invention, this pseudo means is achieved by adopting a so-called duty drive system in which the element has a constant basic period "T" and is driven with "x pulses" at each interval thereof.

Now, in this case, the defocus amount D per one pulse of the pulse motor is expressed by equation (1).

D=DFC×FLK
...
(1) As mentioned above, FLK is the focusing lens extension amount per one pulse of the focusing pulse motor, and DFC is the coefficient of the focusing lens extension amount and defocus.

Here, if Dm is the maximum defocus amount and P is the number of pulses such that the defocus amount becomes 0 when P pulse driving is performed, the relationship shown in equation (2) is established.

Dm/D=P

(2) Using this Dm, the maximum diameter of the circle of confusion δm in the open aperture state can be obtained as shown in equation (3).

δm=Dm/F
・
(3) Here, F is the open F-No. of the lens.

Further, when the diameter of the circle of confusion is to be reduced to 0 at a certain speed Vn (mm/sec), the time Tt required is expressed by equation (4).

Tt=δm/Vn
(sec) (4) Note that n in the suffix represents the type of driving speed from the camera. For example, when n=0 to 15, there are 16 types of driving speed.

The number of times R of driving at this time is expressed by equation (5), where T is the driving period per time.

R=Tt/T

(5) Then, when the number x of pulses per drive when the diameter of the maximum circle of confusion is set to 0, the number x of pulses per drive is determined as shown in equation (6).

x=P/R

(6) By substituting and transforming equations (1) to (5) into equation (6), equation (7) can be obtained.

x = (T×F×Vn)/(D
FC×FLK) (7) By transforming the equation (7), the speed Vn can be expressed as in the equation (8). Vn = (x×DFC×FLK
)/(T×F) (8) Equation (8) is a relational expression between the normalized speed information provided by the video camera and the drive information provided to the lens. If the drive cycle is fixed in equation (8), in order to pseudo-achieve the speed given by the camera, a drive command that drives the x-pulse lens expressed by equation (9) can be sent to the lens at each drive cycle. It would be a good thing to give to them.

x = (Vn×T×F)/(D
FC×FLK) ... (9) In the above embodiment,
This calculation of the number of pulses is performed by the calculation means (305). When an AF control command is received from the camera side, the conversion microcomputer (303) uses the calculation means (305) to calculate the formula (9), and transmits the resulting number of pulses to the lens side at a constant cycle. . Based on this data, the lens drives the pulse motor at regular intervals, thereby making it possible to drive the focusing lens unit (202) required by the camera. FIG. 4 shows a flowchart outlining the processing of the conversion microcomputer in this case.

In FIG. 4, when control in the conversion adapter starts, initial processing such as clearing the internal RAM, setting up various internal states, input/output ports, etc. is performed in S1. Next, in S2, serial communication with the camera is performed. In reality, the camera side becomes the master of this serial communication, and the conversion microcomputer processes, for example, an external interrupt, but this expression is used for convenience of explanation because it does not affect the content of the present invention.

[0071] At S3, the contents of the above serial communication are serially -
Parallel conversion is performed and AF control data is extracted.

In S4, it is determined whether the given AF control command is a command to actually drive the motor. If it is not a drive command (for example, a stop command), the process returns to S2, and if it is a drive command, the process from S5 onwards is performed.

At S5, the speed of the control command (n=0 to 1
5) The speed Vn is calculated according to the above.

Next, in S6, S7, and S8, F, DFC, and FLK data are obtained from the lens, respectively. Specifically, the code corresponding to each data request command is converted from parallel to serial to the lens and sent to the lens in the form of serial communication, and each data obtained from the lens is converted from serial to parallel. obtain.

In S9, based on the data obtained above, the number x of drive pulses to be actually sent to the lens is determined by fixing the drive cycle (for example, 48 msec) according to the above equation (9). The determined number of pulses is outputted to the lens in the form of a focusing motor drive command in S10. Specifically, the code corresponding to the focusing motor drive command and the number of drive pulses are converted from parallel to serial and sent to the lens in the form of serial communication.

Furthermore, in S11, a timer for creating a repetitive drive cycle is started.

At S12, it is determined whether the timer has ended (the next drive pulse output timing), and if the timer has ended, the process returns to S10 and the drive pulse is outputted to the lens again. If the timer has not ended, the command from the camera is checked in S13 and S14, and if the drive command has not changed in S15, the process returns to S12 to continue checking the timer, and if the drive command has changed. is S4
Return to and recalculate the number of pulses.

With this, even when a lens unit of a different format, for example, for a still camera, is attached to a video camera, differences in motor characteristics, speed information, etc. can be calculated using the conversion adapter. It can be controlled in the same way as a dedicated video camera lens.

Next, a second embodiment of the present invention will be described. According to the embodiments described above, the calculation of the number of pulses was performed by the calculation means (305), but this embodiment is characterized in that it is performed by the data conversion means (304).

That is, it is disadvantageous in terms of processing power to execute the calculations mentioned in the first embodiment every time a drive command is given from the camera.

[0081] Therefore, it is possible to cope with this by having a corresponding conversion table as the data conversion means (304), for example. An example of this conversion table is shown in Figure 5.
Shown below.

The table in the figure shows the drive repetition period (
T) = 48 msec, DFC = 2.5, open F-No (
F)=3.51, Vn=2^(n/2-5), and FL
The number of pulses (x) when K is varied is determined in advance using equation (9), and the results are tabulated. A plurality of such tables are provided in the range of DFC and F, and the required number of pulses is determined by switching the tables to be used according to the data from the lens. Since the subsequent processing is the same as that of the first embodiment described above, the explanation will be omitted.

Further, as a third embodiment of the present invention, a case will be described below in which both the calculation means (305) and the data conversion means (304) are used for the above-mentioned calculation of the number of pulses.

The conversion table in the second embodiment is effective when the range of data obtained from lenses is narrow to some extent, but the amount of the table increases when the range of data obtained from various lenses is wide. It is disadvantageous due to the capacity problem of the microcomputer.

Therefore, in equation (9), we separate the information that changes depending on the state of the lens and the information that does not change, calculate the part that does not change depending on the state of the lens in the initial stage, and convert it into a table in the microcomputer. hold it in
This method re-executes the calculation when the data changes depending on the data and the state of the lens.

In equation (9), F and FLK are the former information, and DFC is the latter information. In addition, T is the drive period and can be considered as a constant, and Vn is the speed determined by the format, so for example, if there are from V0 to V15, each speed can be treated as a constant, and in the end, (10) Calculate a constant C like the formula in advance, save it in the microcontroller, and use the DF
Each time C changes, calculations like equation (11) are performed on the speed Vn, and the result is set as a speed table in the microcomputer.When a drive command from the camera is given, the above table is used for each drive cycle. It is sufficient to refer to the data and output a drive command for the lens. FIG. 6 shows a flowchart outlining the processing within the conversion microcomputer at this time.

[0087] Here, C = (T×F)/FLK
...(10)x = C×Vn/DFC
...(11) In Fig. 6, first S
1' performs initial processing such as clearing the internal RAM, setting up various internal states, and input/output ports.

Next, in S2', S3', and S4', F, DFC, and FLK data are obtained from the lens. Specifically, the code corresponding to each data request command is converted from parallel to serial to the lens and sent to the lens in the form of serial communication, and each data obtained from the lens is converted from serial to parallel. obtain.

Next, in S5', Vn is adjusted according to each control speed.
Find the value of. This value can be found by calculation, or
Furthermore, since it can be handled as a constant as described above, it is also possible to store the calculated value in advance in the form of a table in the microcomputer and use that data.

[0090] Based on each data obtained in S2' to S5', the driving period is fixed (for example, 48 msec), and in S6'
, S7', the constant C and the number x of driving pulses to be actually sent to the lens are determined according to equations (10) and (11).

Next, in S8', serial communication with the camera is performed. In reality, the camera side becomes the master of this serial communication, and the conversion microcomputer processes, for example, an external interrupt, but this expression is used for convenience of explanation because it does not affect the content of the present invention. At S9', the contents of the serial communication are serial-parallel converted and AF control data is extracted.

Next, in S10', it is determined whether or not the AF control command given is a command to actually drive the motor, and if it is not a drive command (for example, a stop command), S8'
Return to If it is a drive command, the following processing is performed in S11'. Among the number of pulses obtained in S7' or S19' to be described later, the number of pulses corresponding to the speed information of the drive command is set in S1.
1' outputs to the lens in the form of a focusing motor drive command.

Specifically, the code corresponding to the focusing motor drive command and the number of drive pulses are converted from parallel to serial and sent to the lens in the form of serial communication.

Further, in S12', a timer for creating a repetitive drive cycle is started, and in S13', the end of this timer (the next drive pulse output timing) is determined, and if the timer has ended, the process returns to S11'. The drive pulse is output to the lens again. If the timer has not finished, the command from the camera is sent to S14', S1
If the drive command has changed in S15', the process returns to S10' to change the number of pulses and output the drive command to the lens again. If the drive command has not changed, the DFC value is obtained by communicating with the lens in S17'. This value is compared with the previous value in S18'. If it has not changed, return to S13' and continue checking the timer; if it has changed, proceed to S19' again (11). The number of pulses for each speed is calculated according to the formula, and after confirming the end of the drive cycle in S13', the process returns to S11' and a drive command is output to the lens with a new number of pulses.

In this way, by using the conversion adapter to convert the control information signal regarding the focus lens driving speed from the video camera into the format of the still camera lens and transmitting it to the still camera lens, it is possible to Incompatible lens units can be controlled in the same way as dedicated lenses, and good AF control can be performed.

[0096]

[Effects of the Invention] As described above, when a lens of a different format, for example, for a still camera, is attached to a video camera system, the conversion means of the present invention or the conversion adapter as the conversion means can be used. , the control information from the video camera can be converted and supplied to the control form of the Still camera system, and when the Still camera system interchangeable lens is connected to the camera of the Video Movie interchangeable lens system,
Good AF control becomes possible.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing a schematic configuration of a conversion adapter device.

FIG. 2 is a block diagram illustrating a control signal path for a portion that performs electrical processing within the conversion adapter device.

FIG. 3 is a block diagram of AF control in the first embodiment of the present application, which uses a conversion adapter in the interchangeable lens system.

FIG. 4 is a flowchart showing the processing of the microcomputer in the conversion adapter in the first embodiment of the present invention.

FIG. 5 is a diagram showing a conversion table used in the second embodiment of the present invention.

FIG. 6 is a flowchart showing processing of a conversion microcomputer in a third embodiment of the present application.

FIG. 7 is a block diagram of AF control in an integrated video movie.

FIG. 8 is a block diagram of AF control in the interchangeable lens video camera system.

FIG. 9 is a block diagram of AF control in the still camera system.

Claims (2)

[Claims] Claim 1: The control information output from the camera body is
In an interchangeable lens system that controls a first lens unit by communicating with the first lens unit in the form of a signal,
An adapter device capable of connecting a second lens unit controlled by control information in a second signal format different from the first signal format to the camera body, the adapter device converting means for decoding the control information in the first signal form output from the converter and converting it into a control signal in the second signal form; and control converted into the second signal form by the converting means. A conversion adapter device for an interchangeable lens system, comprising means for communicating information to the second lens unit. 2. A control system that controls a first control object by communicating control information output from a control means to the first control object in a first signal form, wherein the control means receives the first signal. An adapter device capable of connecting a second controlled object controlled by control information in a second signal format different from the first signal format, the adapter device being configured to connect to a second controlled object controlled by control information in a second signal format different from the first signal format. converting means for decoding the control information in the form and converting it into the control signal in the second signal form, and transmitting the control information converted into the second signal form by the converting means to the second control target. 1. A conversion adapter device for a control system, comprising: and means for communicating.