JP3832936B2 - LENS DEVICE, IMAGING DEVICE, AND COMPUTER-READABLE RECORDING MEDIUM - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a lens apparatus suitable for use in a video camera or the like such that a lens can be exchanged, an imaging apparatus using the lens apparatus, and a computer-readable recording medium.
[0002]
[Prior art]
An interchangeable lens system used in a video apparatus such as a conventional video camera will be described with reference to FIG. In a conventional lens unit 1516 capable of zooming, the zoom lens 1502 and the correction lens 1503 are mechanically connected by a cam (not shown), and when the zooming operation is performed manually or electrically, the zoom lens 1502 is operated. And the correction lens 1503 move together.
[0003]
The variable power lens 1502 and the correction lens 1503 are collectively referred to as a zoom lens. In such a lens system, the front lens is the focus lens 1501, which is focused by moving in the optical axis direction. The light passing through these lens groups forms an image on the image pickup surface of an image pickup device 1504 such as a CCD in the camera body 1517, is photoelectrically converted into an electric signal, and is output as a video signal.
[0004]
This video signal is sampled and held by the CDS / AGC 1505, amplified to a predetermined level, converted into digital video data by the A / D converter 1506, and input to a camera process circuit (not shown). It is converted into a standard television signal and input to a bandpass filter 1507 (hereinafter referred to as BPF).
[0005]
The BPF 1507 extracts a high frequency component from the video signal, extracts only the signal corresponding to the portion set in the focus detection area in the screen by the gate circuit 1508, and synchronizes with the integer multiple of the vertical synchronization signal by the peak hold circuit 1509. Peak hold is performed at intervals to generate an AF evaluation value. The AF evaluation value is taken into the main body microcomputer 1510, the focusing speed according to the degree of focus and the motor driving direction are determined so that the AF evaluation value increases in the main body microcomputer 1510, and the speed and direction of the focus motor 1513 are determined. This is sent to the lens microcomputer 1511.
[0006]
The lens microcomputer 1511 performs focus adjustment by moving the focus lens 1501 in the optical axis direction by the motor 1513 via the motor driver 1512 as instructed by the main body microcomputer 1510. Here, the focusing speed determined in the main body microcomputer 1510 is controlled so as to make the change speed of the confusion circle diameter constant from the optical system state (F number, focal length, etc.) of the lens unit 1516 attached. .
[0007]
Further, the main body microcomputer 1510 determines the driving direction and driving speed of the zoom lenses 1502 and 1503 in accordance with the operation state of the zoom switch 1518 and sends it to the zoom motor driver 1514 via the lens microcomputer 1511 in the lens unit 1516. The zoom lenses 1502 and 1503 are driven via 1515.
[0008]
The camera body 1517 can detach the lens unit 1516, and the photographing range is expanded by connecting another lens unit. Transmission of lens control information from the main body microcomputer 1510 to the lens microcomputer 1511 is performed by communication between both microcomputers.
[0009]
In this communication, in order to confirm what kind of function the lens is connected to, it asks the lens for specific information of the lens, and after the specific information of the lens is revealed, that is, to the lens. After recognizing what kind of control is possible, control information suitable for each lens is transmitted, and the current function status is received from the lens side. Here, communication for requesting lens specific information is referred to as “initial communication”, and communication for controlling the function of the lens is referred to as “control communication”.
[0010]
Next, a mutual communication method in the conventional lens exchange system will be described with reference to FIGS.
FIG. 18 shows a communication (DCTL) flow in the camera body on the master side, and FIG. 19 shows a communication (DLTC) flow in the lens unit on the slave side.
[0011]
In FIG. 18, when the camera starts the control operation, it first performs a predetermined initial process (S1602). This content includes, for example, various controls, initialization of registers used for calculation, speed setting of serial communication, and the like. After the initial process is completed, the initial communication mode is entered (S1603). First, it is confirmed by the “lens specification request command” what kind of lens the currently connected partner is (S1604). Based on this result, the presence / absence of the AF unit of the connecting lens is confirmed (S1605). If the AF unit exists, the specification of the unit is recognized by the “unit specification request command” (S1606).
[0012]
If the zoom unit is capable of controlling the angle of view, the same processing as that of the AF unit is performed (S1607, S1608), and while performing control communication (S1609), AF is performed based on the lens-specific data obtained by the initial communication. Control (S1610) and zoom control are executed (S1611). Thereafter, AF / zoom control is repeatedly performed with reference to the return data from the lens side. If there is lens attachment / detachment or the like during the control and the initial communication of the lens is required again, the processing proceeds to S1603 ( S1612).
[0013]
In FIG. 19, after starting the operation and performing the initial processing (S1702), the lens side waits for reception of initial communication (S1703). Then, data corresponding to the transmitted command of the initial communication command “or” control communication command is returned to the camera side. (S1704, S1705, S1706, S1707). The above flow is repeated to perform unit control on the lens side.
[0014]
On the other hand, in a camera / lens integrated camera for consumer use, in order to enable downsizing and shooting up to the front of the lens, the correction lens and zoom lens are not mechanically connected by a cam, and the correction lens movement locus In-focus type lenses, in which the lens is stored in advance in the microcomputer as lens cam data, the correction lens is driven in accordance with the lens cam data, and the focus is adjusted by the correction lens, are becoming mainstream. Such a lens system has advantages such as low cost, simplification of the system, and reduction in size and weight of the lens barrel.
[0015]
FIG. 20 shows a simple configuration of a conventionally used inner focus type lens system. In FIG. 20, reference numeral 1801 denotes a fixed first lens group, 1802 denotes a second lens group that performs zooming, 1803 denotes a stop, 1804 denotes a fixed third lens group, and 1805 denotes a focus adjustment function. A fourth lens group (hereinafter referred to as a focus lens) having a so-called competition function for correcting the movement of the focal plane due to magnification, 1806 is an image sensor such as a CCD.
[0016]
As is well known, in the lens system configured as shown in FIG. 20, since the focus lens 1805 has both a competition function and a focus adjustment function, even if the focal lengths are equal, the imaging system 1806 is focused on the imaging surface. The position of the focus lens 1805 for doing so varies depending on the subject distance. When the subject distance is changed at each focal length, the position of the focus lens 1805 for focusing on the imaging surface is continuously plotted as shown in FIG. During zooming, if the locus shown in FIG. 21 is selected according to the subject distance and the focus lens 1805 is moved along the locus, zooming without blurring becomes possible.
[0017]
In the above-mentioned front lens focus type lens system, a compensator lens independent of the variable power lens is provided, and the variable power lens and the compensator lens are coupled by a mechanical cam ring. Therefore, for example, when a knob for manual zooming is provided on this cam ring, and the focal length is changed manually, the cam ring will follow the rotation no matter how fast the knob is moved, and the zoom lens and the zoom lens Since the lens moves along the cam groove of the cam ring, the above operation does not cause blurring if the focus lens is in focus.
[0018]
On the other hand, in the control of the lens system of the inner focus type as shown in FIG. 20, it is stored in some form (the locus itself or a function with the lens position as a variable) from a plurality of pieces of locus information shown in FIG. In general, one locus is selected depending on the positions of the focus lens and the zoom lens, and zooming is generally performed while following the selected locus.
[0019]
Further, since the position of the focus lens with respect to the position of the variable power lens is read from the storage element and used for lens control, the position of each lens must be read with a certain degree of accuracy. In particular, as is clear from FIG. 21, when the variable magnification lens moves at a constant speed or a speed close thereto, the inclination of the focus lens locus changes every moment due to the change in the focal length. This indicates that the moving speed and the moving direction of the focus lens change every moment. In other words, the actuator of the focus lens must give a speed response with high accuracy from 1 Hz to several hundred Hz. Become.
[0020]
As an actuator that satisfies the above requirements, it is becoming common to use a stepping motor for the focus lens group of the inner focus lens system. The stepping motor rotates in complete synchronization with the stepping pulse output from the lens control microcomputer, etc., and the stepping motor has a constant stepping angle, so high speed responsiveness, stopping accuracy and position accuracy can be obtained. Is possible. Further, when a stepping motor is used, since the rotation angle with respect to the number of stepping pulses is constant, the stepping pulse can be used as it is as an incremental encoder, and there is an advantage that a special position encoder need not be added. .
[0021]
[Problems to be solved by the invention]
In the above-described conventional inner focus type lens system, a stepping motor is used as the actuator, and the position of the focus compensator and the variable power lens is recognized by a microcomputer by serving as an incremental position encoder. In many cases, the control is performed based on the position. In such a system, the absolute position of each lens position is determined by setting the step pulse counter value to a specific value before detecting the position with the stepping motor. An initialization process is required to be reset.
[0022]
If this initialization process is not performed properly, the origin of the stepping pulse counter value and the origin of the combined coordinates of the variable magnification lens position and the focus lens position stored in the microcomputer will be in a state of deviation, For this reason, the trajectory information obtained from the combination coordinates cannot be read correctly, and the trajectory cannot be accurately traced during zooming, resulting in blurring.
[0023]
Therefore, many methods are used to reset the stepping pulse counter by moving the variable power lens or focus lens to a predetermined position immediately after turning on the power and before starting normal operation. In general, the photographed image is not displayed on the screen.
[0024]
On the other hand, in the conventional front lens focusing lens type interchangeable lens system, since the variable power lens and the compensator lens are mechanically integrated, the focus lens independently has the maximum AF evaluation value even during variable power. There is no need to manage the position of each lens group as an absolute position. Therefore, since it is not necessary to initialize the lens position, the lens power circuit is turned on immediately in conjunction with the power supply supplied from the main body, and there is no problem even if the image is output immediately.
[0025]
However, when the inner focus type lens as described above is applied to an interchangeable lens system, the correction lens and the variable power lens are managed by the microcomputer. Until now, it was not clearly presented.
[0026]
For example, when the camera body controls the lens position initialization process on the lens unit side as in the past, the reset operation is controlled via the communication means, so control communication after the initial communication starts normally. Until reset, and the reset operation control must be performed in synchronization with the communication execution cycle (the method in which the lens unit passes data corresponding to the communication command from the main body). Therefore, a plurality of times of communication are required to perform a predetermined operation), and there is a problem that the time required from the completion of the initialization to the image output becomes long.
[0027]
In addition, in the front lens focusing type interchangeable lens system, it is not necessary to manage the focus lens position as an absolute position, so when one lens unit is mounted on multiple camera units, the length of the flange back in each case There was no problem even if it was scattered.
[0028]
However, in the interchangeable lens system of the inner focus type, even if the focus lens position is managed as an absolute position, if the relative position between the imaging surface of the image sensor and the focus lens varies depending on the combination of mounting, the cam trajectory is accurate. I was unable to trace to. As a countermeasure against this problem, a method has been proposed in which information on flange back displacement is exchanged between units, the mutual features are clarified, and then a normal reset operation is performed after a lens reset operation. Also in this case, there is a problem that it takes time until the image is output after the reset operation is completed.
[0029]
The object of the present invention is to solve the above-mentioned problems, and to provide an interchangeable lens system that can connect not only the conventional front lens focus type but also an inner focus type lens unit and the like, and can connect any type of lens system. It is to be.
[0030]
[Means for Solving the Problems]
The lens device according to the present invention is a lens device having a lens system that is detachably connected to the imaging device and includes a movable lens, and communication between the initialization device that performs initialization processing of the position of the movable lens and the imaging device. Communication means for performing the processing in parallel independently of the initialization processing is provided.
[0031]
In the imaging apparatus according to the present invention, the lens system having the movable lens, the initialization process of the position of the movable lens, the initialization means for outputting the information indicating the end of the process, and communication of various information, A lens unit having a first communication unit that performs the communication process in parallel with the initialization process; a second communication unit that performs a communication process with the first communication unit; and the lens system. An image pickup means for picking up an image of a subject formed through the image processing means, outputting an image signal, an image processing means for processing the image signal, and the initialization process from the initialization means through the first and second communication means. A camera body having prohibiting means for prohibiting output of the image signal processed by the image processing means until information indicating the end of the image processing is obtained.
[0032]
In a computer-readable recording medium according to the present invention, a procedure for initializing the position of the movable lens in a lens device having a lens system that is detachably connected to the imaging device and includes a movable lens, and the imaging device A program for executing the communication process in parallel with the initialization process in parallel with the initialization process is recorded.
[0033]
An image pickup apparatus according to the present invention includes an image pickup apparatus main body and an accessory such as a lens detachably connected to the image pickup apparatus main body, an initialization unit that performs initialization processing of the accessory, the image pickup apparatus main body, and the above Communication means for performing communication processing with the accessory in parallel independently of the initialization processing is provided.
[0034]
In the imaging apparatus according to the present invention, a lens system having a movable lens, an initialization unit that initializes the position of the movable lens, and various types of information are communicated, and the communication process is referred to as the initialization process. A lens unit having a first communication unit that performs independently and in parallel, a second communication unit that performs communication processing with the first communication unit, and a second communication unit that responds to power-on. There is provided a camera body having control means for starting communication with the first communication means and operating the initialization means independently and in parallel.
[0035]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below with reference to the drawings.
FIG. 1 is a diagram showing a configuration of an imaging system in which lenses can be exchanged according to the present invention. In FIG. 1, light from an object includes a fixed first lens group 101 in a lens unit 127, a second lens group 102 that performs zooming, a diaphragm 103, and a fixed third lens group 104, It passes through a fourth lens group 105 (hereinafter referred to as a focus lens) having both a focus adjustment function and a competition function for correcting movement of the focal plane due to zooming.
[0036]
The red component in the three primary colors is on the image sensor 106 such as a CCD in the camera body 128, the green component is on the image sensor 107 such as a CCD, and the blue component is on the image sensor 108 such as a CCD. Imaged. Each image on each image sensor is photoelectrically converted, amplified to an optimum level by amplifiers 108, 109, and 110, input to the camera signal processing unit 112, converted into a standard television signal, and an AF signal processing circuit 113. Is input. The AF evaluation value generated by the AF signal processing circuit 113 is read out in the main body microcomputer 114 and transferred to the lens microcomputer 116 through the communication line 115.
[0037]
In the lens unit 127, the switches 133 and 135 are switches for detecting that the lens groups 102 and 105 are at the reference position, and in the figure, each is incorporated in each lens together with the photosensors 134 and 136. . The switches 133 and 135 are fixed to the lens groups 102 and 105, respectively, and move together as the lens groups 102 and 105 move parallel to the optical axis.
[0038]
Then, in the movable region of each lens group, an ON / OFF operation is performed as to whether or not to block the output light of the photosensors 134 and 136 with the vicinity of the middle as a boundary. Depending on whether the output light is blocked or not, the light detection unit of the photosensors 134 and 136 outputs a 1 or 0 signal. Can detect if is there.
[0039]
FIG. 5 is a configuration diagram of a reset switch that operates the lens position counter, and moves the optical path from the light emitting unit 501 to the light receiving unit 502 constituting the photosensor 134 (or 136) together with the lens in parallel with the optical axis. When the shielding plate 133 (or 135) is blocked, the output signal of the light receiving unit 502 is at the Low level, and when not blocked, the output signal is at the Hi level.
[0040]
Further, the main body microcomputer 114 reads the state of the zoom switch 130 and the AF switch 131 and sends the state of the switch to the lens microcomputer 116. In the lens microcomputer 116, when the AF switch 131 is off and the zoom switch 130 is pressed by the information from the main body microcomputer 114, the computer zoom program stored in the memory 119 is pressed to tele or wide. The zoom lens 102 is driven via the zoom motor 121 by sending a signal to the zoom motor driver 122 on the basis of the lens cam data 120 stored in advance in the lens microcomputer 116 in order to drive the lens in the direction. At the same time, a zooming operation is performed by sending a signal to the focus motor driver 126 and moving the focus lens 105 via the focus motor 125.
[0041]
When the AF switch 131 is on and the zoom switch 130 is pressed, it is necessary to keep the focused state. Therefore, the computer zoom program can store only the lens cam data 120 stored in the lens microcomputer 116 in advance. In addition, referring to the AF evaluation value signal sent from the main body microcomputer 114, the zooming operation is performed while maintaining the position where the AF evaluation value becomes maximum. When the AF switch 131 is on and the zoom switch 130 is not pressed, the AF program 117 sends a signal to the focus motor driver 126 so that the AF evaluation value signal sent from the main body microcomputer 114 is maximized. An automatic focus adjustment operation is performed by moving the focus lens 105 via the motor 125.
[0042]
The memory 119 is a recording medium according to the present invention. In addition to the computer zoom program, a program for executing processing of flowcharts shown in FIGS. 4, 14, 15, and 16 to be described later is recorded. Has been. The memory 137 used by the main body microcomputer 114 in the camera main body 128 stores a program for processing in the flowchart of FIG. As each recording medium described above, a semiconductor memory, an optical disk, a magneto-optical disk, a magnetic medium, or the like may be used, and a ROM, a RAM, a memory card, a floppy disk, a CD, or the like may be used.
[0043]
Next, the AF signal processing unit 113 will be described with reference to FIG. The red (R), green (G), and blue (B) CCD outputs amplified to optimum levels by the amplifiers 108, 109, and 110 in FIG. 1 are respectively converted into A / D converters 206, 207, and FIG. The digital signal is converted into a digital signal at 208 and sent to the camera signal processing unit 112 in FIG. 1. At the same time, it is appropriately amplified by the amplifiers 209, 210, and 211, and added by the adder 208. Is made.
[0044]
This signal S5 is input to the gamma circuit 213 and gamma-converted with a predetermined gamma curve to produce a signal S6 in which the low luminance component is emphasized and the high luminance component is suppressed. The gamma converted signal S6 is input to the TE-LPF 214, which is an LPF with a high cut-off frequency, and the FE-LPF 215, which is an LPF with a low cut-off frequency, and the respective filters determined by the main body microcomputer 114 through the microcomputer interface 253. The low frequency component is extracted by the characteristics, and the TE-LPF 214 output signal S7 and the FE-LPF 215 output signal S8 are generated.
[0045]
The signal S7 and the signal S8 are selected by the Line E / 0 signal, which is a signal for identifying whether the horizontal line is an even-numbered or odd-numbered signal by the switch 216, and input to a high-pass filter (hereinafter, HPF) 217. That is, the even line passes the signal S7 to the HPF 217, and the odd line passes the signal S8. In the HPF 217, only the high frequency component is extracted by the filter characteristics of the odd number / even number determined by the main body microcomputer 114 through the microcomputer interface 253, and is converted into an absolute value by the absolute value circuit 218, thereby generating a positive signal S 9. The signal S9 is input to the peak hold circuits 225, 226, 227 and the line peak hold circuit 231.
[0046]
The frame generation circuit 254 generates focus adjustment gate signal L frame, C frame, and R frame at positions in the screen as shown in FIG. The peak hold circuit 225 receives a Line E / 0 signal that is a signal for identifying whether the L frame and the horizontal line of the frame generation circuit 254 output are even-numbered or odd-numbered, and as shown in FIG. The peak hold circuit 225 is initialized at each position of the upper left LP1 which is the top of the frame, and the signal S9 in each frame of either the even line or the odd line designated from the main body microcomputer 114 through the microcomputer interface 253 is peaked. The peak hold value in the frame is transferred to the buffer 228 by IR1, and a TE / FE peak evaluation value is generated.
[0047]
Similarly, the C frame and Line E / 0 signal output from the frame generation circuit 254 are input to the peak hold circuit 226, and the peak hold circuit 225 is displayed at the upper left CR1 which is the head of the focus adjustment C frame shown in FIG. The signal S9 in each frame of either the even line or the odd line designated through the microcomputer interface 253 is peak-held from the microcomputer, the peak hold value in the frame is transferred to the buffer 229 by IR1, and the TE / FE peak evaluation value is generated.
[0048]
Similarly, the R frame and Line E / 0 signal output from the frame generation circuit 254 are input to the peak hold circuit 227, and the peak hold circuit RR1 is the top left RR1 which is the head of the focus adjustment R frame shown in FIG. 227 is initialized, the signal S9 in each frame of either the even line or the odd line designated from the main body microcomputer 114 through the microcomputer interface 253 is peak-held, and the peak hold value in the frame is transferred to the buffer 230 by IR1. Then, the TE / FE peak evaluation value is generated.
[0049]
The line peak hold circuit 213 receives the signal S9 and the L frame, C frame, and R frame output from the frame generation circuit 254, is initialized at the horizontal start point in each frame, and outputs the signal S9 in each frame. Hold the peak value of one line.
[0050]
The integration circuits 232, 233, 234, 235, 236, and 237 receive the output of the line peak hold circuit 231 and the Line E / 0 signal that is a signal for identifying whether the horizontal line is even or odd, and at the same time, integrate. The circuits 232 and 235 receive the L frame of the frame generation circuit 254 output, the integration circuits 233 and 236 receive the C frame of the frame generation circuit 254 output, and the integration circuits 234 and 237 receive the R frame of the frame generation circuit 254 output. The The integration circuit 232 initializes the integration circuit 232 with the upper left LR1 that is the head of the L frame for focus adjustment, and adds the output of the line peak hold circuit 231 to the internal register immediately before the end of the even line in each frame. Then, the peak hold value is transferred to the buffer 238 by IR1, and the line peak integration evaluation value is generated.
[0051]
The integration circuit 233 initializes the integration circuit 233 at each location of the upper left CR1, which is the head of the focus adjustment C frame, and internally outputs the output of the line peak hold circuit 251 immediately before the end of the even line in each frame. The value is added to the register, the peak hold value is transferred to the buffer 239 by IR1, and the line peak integration evaluation value is generated. The integration circuit 234 initializes the integration circuit 234 with the upper left RR1 that is the head of the focus adjustment R frame, and adds the output of the line peak hold circuit 231 to the internal register immediately before the end of the even line in each frame. , IR1, the peak hold value is transferred to the buffer 240, and the line peak integration evaluation value is generated.
[0052]
The integration circuits 235, 236, and 237 perform addition of odd-numbered data, respectively, instead of the integration circuits 232, 233, and 234 adding data for even-numbered lines, and transfer the results to the buffers 241, 242, and 243, respectively. . Further, the signal S 7 is input to the peak hold circuits 219, 220, 221, the line maximum value hold circuit 244 and the line minimum value hold circuit 245. The L frame of the frame generation circuit 254 output is input to the peak hold circuit 219, the peak hold circuit 219 is initialized at the upper left LR1, which is the head of the L frame, and the signal S7 in each frame is peak-held. In IR1, the peak hold result is transferred to the buffer 222, and a Y peak evaluation value is generated.
[0053]
Similarly, the C frame of the frame generation circuit 254 output is input to the peak hold circuit 220, the peak hold circuit 220 is initialized with the upper left CR1 which is the head of the C frame, and the signal S7 in each frame is peaked. Hold and transfer the peak hold result to the buffer 223 with IR1 to generate a Y peak evaluation value. Similarly, the R frame output from the frame generation circuit 254 is input to the peak hold circuit 221, and the peak hold circuit 221 is initialized with the upper left RR1 that is the head of the R frame, and the signal S7 in each frame is initialized. , And the peak hold result is transferred to the buffer 224 by IR1 to generate a Y peak evaluation value.
[0054]
The line maximum value hold circuit 244 and the line minimum value hold circuit 245 receive the L frame, C frame, and R frame output from the frame generation circuit 254 and are initialized at the horizontal start point in each frame. Each maximum value and minimum value of one line of the signal S7 is held. The maximum value and minimum value held by these are input to the subtractor 246 (maximum value-minimum value), and the signal S10 is calculated and input to the peak hold circuits 247, 248, 249.
[0055]
The L frame of the frame generation circuit 254 output is input to the peak hold circuit 247, the peak hold circuit 247 is initialized by the upper left LR1 which is the head of the L frame, the signal S10 in each frame is peak-held, and IR1 Then, the peak hold result is transferred to the buffer 250, and a Max-Min evaluation value is generated. Similarly, the C frame of the frame generation circuit 254 output is input to the peak hold circuit 248, and the peak hold circuit 248 is initialized at the upper left CR1 which is the head of the C frame, and the signal S10 in each frame is peak-held. Then, with IR1, the peak hold result is transferred to the buffer 251, and the Max-Min value is generated.
[0056]
Similarly, the R frame of the frame generation circuit 254 output is input to the peak hold circuit 249, and the peak hold circuit 249 is initialized at the upper left RR1 which is the head of the R frame, and the signal S10 in each frame is peaked. Hold, transfer the peak hold result to the buffer 252 with IR1, and generate the Max-Min evaluation value.
[0057]
At each location of IR1, the frame generation circuit 254 simultaneously transfers data to the buffers 222, 223, 224, 228, 229, 230, 238, 239, 240, 241, 242, 243, 250, 251, 252, An interrupt signal is sent to the microcomputer 114. Upon receiving the interrupt signal, the microcomputer 114 downloads each data in the buffers 222, 223, 224, 228, 229, 230, 238, 239, 240, 241, 242, 243, 250, 251, 252 through the microcomputer interface 253. Is read before the next data is transferred to the buffer and transferred to the lens microcomputer 116.
[0058]
FIG. 3 is a diagram for explaining the timing in the AF signal processing unit 113. The outer frame is an effective video screen output from the image sensors 106, 107, and 108. The inner three frames are focus adjustment gate frames, and the left L frame, the central C frame, and the right R frame are output from the frame generation circuit 254.
[0059]
A reset signal is output for each of the L, C, and R frames at the start positions of these frames to generate LR1, CR1, and RR1, and reset the integration circuit, peak hold circuit, and the like. At the end of the frame, a data transfer signal IR1 is generated, and each integral value and peak hold value are transferred to each buffer. Further, even field scans are indicated by solid lines, and odd field scans are indicated by dotted lines. In both the even field and the odd field, the even line selects the TE-LPF output, and the odd line selects the FE-LPF output.
[0060]
Next, TE / FE peak evaluation value, TE line peak integration evaluation value, FE line peak integration evaluation value, Y peak evaluation value, Max-Min evaluation value in each frame, how the microcomputer performs automatic focus adjustment Explain what to do. The TE / FE peak evaluation value is an evaluation value representing the degree of focus, and since it is a peak hold value, it is relatively less subject-dependent and less affected by camera shake, etc., and is optimal for focus degree determination and restart determination. The TE line peak integration evaluation value and the FE line peak integration evaluation value also indicate the degree of focus. However, since the integration effect is a stable evaluation value with little noise, it is optimal for direction determination.
[0061]
Furthermore, both the peak evaluation value and the line peak integration evaluation value are optimal in the vicinity of the focus because TE extracts higher frequency components, and conversely, FE is optimal in the case of a large blur far from the focus. Further, since the Y peak evaluation value and the Max-Min evaluation value do not depend on the degree of focus so much and depend on the subject, in order to reliably perform the focus determination level, the restart determination, and the direction determination, the situation of the subject is grasped. Is ideal for.
[0062]
In other words, the Y peak evaluation value is used to determine whether the subject is a high brightness subject or a low illumination subject, the Max-Min evaluation value is used to determine the contrast level, the TE / FE peak evaluation value, the TE line peak integration evaluation value, and the FE line peak. Optimal control is achieved by predicting and correcting the peak of the integral evaluation value. These evaluation values are transferred from the camera body 128 to the lens unit 127, and an automatic focus adjustment operation is performed by the lens microcomputer 116 in the lens unit 127.
[0063]
FIG. 4 is a flowchart of the algorithm of the automatic focus adjustment operation when the zooming operation is not performed in the lens microcomputer 116 in the lens unit 127. First start (A1), apply speed control at the peak level of TE or FE, and control direction using mainly TE line peak integral evaluation value near the top of mountain and FE line peak integral evaluation value at mountain foot By doing so, hill climbing control (A2) is performed.
[0064]
Next, a peak apex judgment (A3) is performed based on the absolute value of the TE or FE peak evaluation value or the change amount of the TE line peak integral evaluation value, the peak is stopped at the highest level, and the restart standby (A4) is entered. . In the restart standby, it is detected that the level of the TE or FE peak evaluation value has been lowered and restarted (A5). In this automatic focus adjustment loop, the degree of speed control using the TE / FE peak, the absolute level of peak judgment, the amount of change in the TE line peak integral evaluation value, etc. The size of the mountain is predicted based on subject determination using the Max-Min evaluation value, and is determined based on this.
[0065]
Next, the relationship between the movement of the variable power lens 102 and the focus lens 105 when performing the variable power operation, and how to refer to the AF evaluation value signal during the variable power operation from wide to tele are described. In the lens system configured as shown in FIG. 1, the focus lens 105 has both a competition function and a focus adjustment function, so that even when the focal lengths are equal, the imaging surfaces of the imaging elements 106, 107, and 108 are focused. Therefore, the position of the focus lens 105 varies depending on the subject distance.
[0066]
When the subject distance is changed at each focal length, the position of the focus lens 105 for focusing on the imaging surface is continuously plotted as shown in FIG. During zooming, if the locus shown in FIG. 21 is selected according to the subject distance and the focus lens 105 is moved according to the locus, zoom without blur can be achieved as described in the conventional example. It is.
[0067]
In the front lens focus type lens system, a compensator lens independent from the variable power lens is provided, and the variable power lens and the compensator lens are coupled by a mechanical cam ring. Therefore, for example, when a knob for manual zooming is provided on this cam ring, and the focal length is changed manually, the cam ring will follow the rotation no matter how fast the knob is moved, and the zoom lens and the zoom lens Since the lens moves along the cam groove of the cam ring, the above operation does not cause blurring if the focus lens is in focus.
[0068]
However, in the control of the inner focus type lens system having the above-described characteristics, when the zooming operation is performed while maintaining the in-focus state, the locus information of FIG. 21 is stored as the lens cam data 120 in the lens microcomputer 116. In addition, it is necessary to read the trajectory information according to the position or moving speed of the zoom lens and move the focus lens based on the information.
[0069]
FIG. 6 is a diagram for explaining an example of a conventionally proposed locus tracking method. In FIG. 6, Z0, Z1, Z2,..., Z6 indicate zoom lens positions, and a0, a1, a2,..., A6 and b0, b1, b2,. It is a representative trajectory. Further, p0, p1, p2,..., P6 are trajectories calculated based on the two trajectories. The calculation formula of this locus is described below.
p (n + 1) = | p (n) −a (n) | / | b (n) −a (n) | * | b (n + 1) −a (n + 1) | + a (n + 1) (1)
[0070]
According to the expression (1), for example, in FIG. 6, when the focus lens 105 is at p0, a ratio that p0 internally divides the line segment b0-a0 is obtained, and the line segment b1-a1 is internally divided according to this ratio. P1. From the position difference of p1 to p0 and the time required for the variable magnification lens 102 to move from Z0 to Z1, the moving speed of the focus lens 105 for maintaining the in-focus state can be known.
[0071]
Next, a description will be given of a case where the stop position of the zoom lens 102 is not limited only to the boundary where the stored representative trajectory data is owned. FIG. 7 is a diagram for explaining an interpolation method in the direction of the zoom lens position. A part of FIG. 6 is extracted and the zoom lens position is arbitrarily set.
[0072]
In FIG. 7, the vertical axis indicates the focus lens position, and the horizontal axis indicates the zoom lens position. The representative locus position (the focus lens position with respect to the zoom lens position) stored in the lens control microcomputer is represented by the zoom lens position. Z0, Z1, ..., Z _k-1 , Zk,..., Zn, and the focus lens position at that time according to subject distance,
a0, a1, ..., a _k-1 , Ak, ..., an
b0, b1, ..., b _k-1 , Bk, ..., bn
It is represented by
[0073]
Now, when the zoom lens position is in Zx not on the zoom boundary and the focus lens position is Px, ax and bx are obtained as follows:
ax = ak− (Zk−Zx) * (ak−a _k-1 ) / (Zk-Z _k-1 ) ......... (2)
bx = bk− (Zk−Zx) * (bk−b _k-1 ) / (Zk-Z _k-1 ) ......... (3)
It becomes.
[0074]
That is, the current zoom lens position and two zoom boundary positions (for example, Zk and Z in FIG. 7). _k-1 ) And four stored representative trajectory data (ak, a in FIG. 7). _k-1 , Bk, b _k-1 Ax and bx can be obtained by internally dividing those having the same subject distance by the internal ratio. Then, according to the internal ratio obtained from ax, Px, bx, four stored representative data (ak, a, _k-1 , Bk, b _k-1 ) And pk, p by dividing the same focal length by the above internal ratio as shown in equation (1). _k-1 Can be requested.
[0075]
In addition, when zooming from wide to tele, a focus lens for maintaining focus from the positional difference between the follow-up focus position pk and the current focus position px and the time required for the zoom lens to move from Zx to Zk. You can see the moving speed. In addition, when zooming from tele to wide, the following focus position p _k-1 Difference between the current focus position Px and the zoom lens Zx to Z _K-1 The moving speed of the focus lens for maintaining the in-focus state can be determined from the time required to move to the position.
[0076]
Further, in order to perform the above-described trajectory tracking, it is necessary to recognize the positions of the focus lens and the variable power lens as absolute positions. Therefore, when the power is turned on, the focus lens and the variable power lens are brought into contact with a predetermined position (reset position) that is an infinite end or a wide end, so that the position coincides with P (0, 0) in FIG. The absolute position is recognized by the microcomputer 116. This is the initialization operation of the focus lens and variable power lens.
[0077]
Further, in order to speed up the initialization operation, as a post-processing when the power is turned off, the positions of the focus lens and the variable power lens are stored in the lens microcomputer 116 and then moved to the vicinity of the reset position, so that the power supply can be restored. It is desirable to use a method that reproduces the same state as before turning off the power by moving to the position of the stored focus lens or variable magnification lens after performing the initialization operation at the time of turning on. The lens reset sequence will be described in detail later with reference to FIGS.
[0078]
Next, a communication method between the main body microcomputer 114 and the lens microcomputer 116 performed via the communication line 115 will be described.
First, the contents of the communication line 115 of the lens microcomputer 116 in the lens unit 127 and the main body microcomputer 114 in the camera main body 114 will be described. The main microcomputer 114 is the master and the lens microcomputer 116 is the slave, and the communication method is performed with a fixed length of 19 bytes by 3-wire clock synchronous serial communication.
[0079]
FIG. 8 specifically shows a communication line 115 between the main body microcomputer 114 and the lens microcomputer 116, and a chip select (CS), a clock synchronization signal (SCLK), and data for controlling the communication timing of the lens microcomputer 116 from the main body microcomputer 114. (DCTL), data (DLTC) from the lens microcomputer 116 to the main body microcomputer 114.
[0080]
FIG. 9 shows the communication timing. From the rising edge of the vertical synchronization signal VD (a), the main body microcomputer 114 lowers the CS (b) for starting communication and sends the clock SCLK (c) 19 times by 8 bits. Synchronously, DCTL (d) of data is transmitted as CTL0 to CTL18 by MSB or LSB. At the same time, the lens microcomputer 116 transmits data DLTC (e) in synchronization with SCLK by means of MSB or LSB as LTC0 to LTC18.
[0081]
FIG. 10 shows communication contents. Initial communication contents from the main body microcomputer 114 to the lens microcomputer 116 (DCTL initial), communication contents at the time of control (DCTL control), and initial communication from the lens microcomputer 116 to the main body microcomputer 114. The contents (DLTC control) and the communication contents during control (DLTC control) each have contents of 0 to 18 bytes. Blank fields are undefined. The 0th byte of each content is a header of communication content, and the 18th byte is a checksum for error detection.
[0082]
Details of the header configuration are shown in FIG. 0 bit of each 0 byte is 1 when 1 bit is 0, initial communication, 0 bit is 0, control communication when 1 bit is 1, 6 bits of the initial 0 bytes of DLTC are initial completion flags, initial when 0 Completion: 1 indicates initial request flag when 7 bits of 0 byte of DLTC control is 1 during initialization.
[0083]
In addition, the checksum of the 18th byte is transmitted by substituting the value of the total of 0 to 18 bytes OFF (Hex) in the 18th byte in each communication. That is, 0 byte + 1 byte + 2 bytes + 3 bytes +... +18 bytes = OFF (Hex). On the other hand, error detection is performed by checking whether the received data is totaled from 0 to 18 bytes to become OFFHex. When it is OFF (Hex), it is determined that the received data is normal, and when it is not, it is determined that the received data is not normal.
[0084]
Next, communication handshaking will be described with reference to FIG. (A) is a system state, (b) is a communication category from the main body microcomputer to the lens microcomputer, (c) is a communication category from the lens microcomputer to the main body microcomputer, and T0, T1, T3,. . When the system status changes from OFF to ON at T0, DCTL starts communication from initial communication, and DLTC also starts from T1 with initial communication.
[0085]
When the lens microcomputer 116 at T2 is initialized, the main body microcomputer 114 changes from initial communication to control communication. Along with this, at T3, the lens microcomputer is changed from the initial communication to the control communication, both of them become control communication, and the system becomes a control operation. When the main body microcomputer wishes to change from control communication to initial communication, the header at T4 is changed from control communication to initial communication. Along with this, the lens microcomputer at the time of T5 is changed from the control communication to the initial communication, both of them become the initial communication, and the system becomes the initial operation.
[0086]
When the lens microcomputer wishes to change from control communication to initial communication, the main microcomputer at T9 is changed from control communication to initial communication by transmitting an initial request at T8 to the main microcomputer, and the lens microcomputer at T10 starts from control communication to the initial communication. After changing to communication, both sides become initial communication, and the system becomes initial operation. Operations T6, T7, T11, and T12 in which the system changes from initial communication to control communication are equivalent to operations at T2 and T3.
[0087]
Next, a communication flow between the main body microcomputer 114 and the lens microcomputer 116 will be described with reference to FIGS. The mutual communication is performed in synchronization with the vertical synchronization signal VD as shown in FIG.
[0088]
FIG. 13 shows a communication flow of the main body microcomputer 114. In S1201, the power is turned on from S1202, the power is turned on in S1202, and the microcomputer is reset in S1203. The communication execution is set to the timing shown in FIG. 9 after waiting until the fall, and transmission of the header is started in the initial communication from S1206.
[0089]
At the same time, the data is received in S1207, and the checksum data is checked in S1208. If normal, the process returns to S1209, and if abnormal, the process returns to S1205. In S1209, the received data header is checked, and if it is initial communication, the process returns to S1210, and if it is control communication, the process returns to S1205. In step S1210, the received data is stored. In step S1211, the initial completion flag is checked. If the initial completion is completed, the process returns to step S1212. If the initial process is in progress, the process returns to step S1205.
[0090]
After waiting for VD to come again in S1212 and managing the communication timing, in S1213, the header is transmitted as control communication and transmitted. In step S1214, the checksum data is checked. If normal, the process returns to S1216, and if abnormal, the process returns to S1212. In S1216, the header of the received data is checked. If it is initial communication, the process returns to S1212, and if it is control communication, the process goes to S1217. In step S1217, the received data is stored, and in step S1218, it is determined whether the lens reset is completed.
[0091]
The determination of the lens reset state is performed by examining the fifth byte data of DLTC control in FIG. If the lens reset is completed, the image output is permitted in S1220, and if it is not completed, the image output is prohibited in S1219. In step S1221, main body control is executed. S1222 is a determination of whether or not the lens unit has been removed. If the lens has been replaced, the process returns to S1205; if not, the process proceeds to S1223; the initial request flag is checked; if there is a request, the process proceeds to S1205; Return
[0092]
FIG. 14 is a communication flow of the lens microcomputer 116. The power is turned on from the OFF state in S1301 and the power is turned on in S1302. The microcomputer is reset in S1303. In S1304, the initial process in the microcomputer and the initial completion flag are reset. In step S1305, it is determined whether the CS signal synchronized with VD is low from the main body microcomputer 114 which is the master, and the communication timing is set to the state shown in FIG.
[0093]
Next, the transmission of the header is started in the initial communication from S1306. At the same time, the data is received in S1307, and the checksum data is checked in S1308. If normal, the process returns to S1309, and if abnormal, the process returns to S1305. In S1309, the header of the received data is checked, and if it is initial communication, go to S1310, and if it is control communication, go to S1314. The received data is stored in S1310, and the initial request flag is reset in S1311 (however, the initial request flag is irrelevant in the reset start).
[0094]
In step S1312, the initial completion flag is checked. If the initial completion is completed, the process returns to step S1313. If the initial completion is in progress, the process returns to step S1305. In step S1313, the initial flag is cleared, and the process returns to step S1305. S1314 is a case where the received header is control communication in S1309. The initial flag is checked, and if completed (cleared), the process returns to S1315, and if initial (set), the process returns to S1305.
[0095]
Next, in step S1315, the process waits until the CS is in a low state. In step S1316, the header is transmitted as control communication. In step S1317, the checksum data is checked. If normal, the process returns to S1319, and if abnormal, the process returns to S1315. In S1319, the received data header is checked, and if it is an initial communication, the process returns to S1305, and if it is a control communication, the process goes to S1320. The received data is stored in S1320, and lens control is executed in S1321. When the lens microcomputer needs initial communication in S1322, the initial request flag is set in S1323 and the process proceeds to S1315. If not necessary, the process returns to S1315.
[0096]
The CS operation used in the process of FIG. 14 is not specified, but is set to Low before the processes of S1206, 1207, 1213, and 1214 of FIG. 13 are executed, and returns to High after the execution. It is controlled as follows. Further, when the lens is attached / detached, the power supplied to the lens unit is once cut off, so when the lens unit is attached again, the processing is executed from S1301.
[0097]
Further, in the lens control in S1321, the absolute position of the focus lens 105 determined by the lens reset is added to the absolute position by adding the flange pack deviation information obtained in the initial stage of CDTL in FIG. , The focus surface deviation is corrected. That is, the amount of flange back deviation of each camera body relative to the reference lens is measured in advance during the production process, stored in the camera body as the amount of deviation from the flange pack design value, and the information is sent to the lens unit by DCTL initial communication. .
[0098]
In the lens unit, based on this information, a value obtained by previously adding an offset value (positive or negative value) corresponding to the direction and amount of deviation from the focus absolute position counter is used as a focus control position counter. It becomes possible to remove the error of the flange back.
[0099]
The “initial request” determined in S1322 is for enabling the lens unit side to request initial communication again. For example, the telecon, wide-con, It is assumed that a lens unit with a built-in attachment lens or the like is built in, and the initial communication can be executed again when the optical system state of the lens unit changes with the attachment of the attachment lens.
[0100]
That is, the optical data is communicated again in order to inform the photographer that the focal length, F number, etc. will change due to the attachment of the attachment lens, and in some cases the usable focal length range will be limited. ing. If this method is not used, the lens optical data exchanged in the initial communication must always be communicated even during the control, so that the communication data increases and the load on the microcomputer processing increases. When the initial request is set in S1322, the main body microcomputer can recognize the initial request in the next control communication, so that the next communication is switched to the initial communication again.
[0101]
Next, the lens reset operation will be described in detail with reference to FIGS. FIGS. 15 and 16 are lens reset operation flows for carrying out the present invention, which are processed by the lens microcomputer 116, and are executed independently from the mutual communication between the lens unit 127 and the camera body 128 described above. It is.
[0102]
In the interchangeable lens system of FIG. 1, the period for supplying the video signal and the AF evaluation value from the main body to the lens side are one field unit of the vertical synchronization period, and the communication period is also performed in synchronization with the vertical synchronization VD. That has already been explained. Similarly, the operation flow of FIG. 15 will be described on the assumption that it is controlled in units of field periods. Note that the processing in FIG. 16 is an operation flow for explaining the processing content of S804 in FIG. 15 in more detail. In S805, the control sequence is the same as that in FIG. Therefore, a detailed description of the focus lens reset operation sequence is omitted here.
[0103]
In FIG. 15, if the process is started in S801 and the power is supplied to the lens unit in S802, the process waits until the vertical synchronization signal VD is received in S803. After waiting, the zoom lens and the focus lens are reset in S804 and 805. Perform the action. In step S806, it is confirmed whether both lenses have been reset. When the reset is completed, a completion flag is set. When the reset is not completed, the completion flag is cleared. This completion flag corresponds to lens reset completion information in the DLTC control communication of FIG. 10, and the main body microcomputer controls permission / prohibition of image output according to this information. After executing S807 and S808, the process returns to S803 again and waits for the next VD.
[0104]
By repeating the above processing, the lens reset operation is finally completed. This sequence will be described in detail with reference to FIG.
FIG. 16 is a flowchart of processing executed in S804 of FIG. In FIG. 16, the zoom lens reset operation mode Mz is confirmed in S901. Mz takes values 0, 1, 2, 3, and 4, and corresponds to modes 0, 1, 2, 3, and 4, respectively.
[0105]
When the lens is mounted or the power is turned on, Mz = 0 because of the RAM clear of the lens microcomputer 116, and the process proceeds to S902. In step S902, the zoom lens position detection counter Cz is cleared. In step S903, it is confirmed whether the output signal of the photosensor 134 is at a high level. For example, when the boundary between the light shielding and the light transmission is approximately in the middle of the movable range of the lens, it is determined from the state of the output signal of the photo sensor 134 whether the boundary is on the tele side with respect to the current lens position. it can.
[0106]
Taking FIG. 5 as an example, when the output signal of the photo sensor 134 is at a low level, it is shielded from light, so the zoom lens 102 is positioned on the tele side with respect to the boundary, and the zoom lens 102 is moved to the wide side. By moving, the change of the output signal of the photosensor 134 from Low to High can be obtained. First, the reverse occurs when the output signal of the photosensor 134 is at a high level.
[0107]
Therefore, the state of the output signal of the photosensor 184 is confirmed in S903, and if it is at a high level, the zoom lens 102 is moved in the tele direction in S904 to obtain a boundary point. At this time, the zoom lens position detection counter Cz is incremented in synchronization with the stepping pulse of the zoom motor 121. On the other hand, if it is determined in S903 that the output signal of the photosensor 134 is at the low level, the operation and determination opposite to S904 are performed in S905, respectively, and one mode is recommended in S906, Mz = 1. Exit this process.
[0108]
When S901 is reached again in the next vertical synchronization, the zoom reset mode Mz is 1, so that the process proceeds from S907. In S907, it is determined whether or not the moving direction of the zoom lens determined in mode 0 is the tele direction. If it is in the tele direction, it is confirmed in S908 whether the output of the photo sensor 134 has changed from High to Low, and if there is no change, the same processing as S904 is performed in S910, and this processing is exited.
[0109]
On the other hand, if it is determined in S907 that the camera is moving in the wide direction, it is confirmed in S909 whether the output of the photo sensor 134 has changed from Low to High. If there is no change, the same processing as S905 is performed in S911, and this processing is exited. In this case, since Mz = 1 remains, the process from S907 is performed again when the process next comes to S803 in FIG.
[0110]
While this is repeated, the state of the photosensor 134 changes in S908 or S909, and the mode Mz = 2 is set in S912. When the mode is 2, the process proceeds to S913. When the process proceeds to S913, the value of the counter Cz indicates the number of stepping pulses of the zoom motor 121 between the zoom lens position and the reset switch position immediately after the power is turned on and before the reset operation is performed. That is, it represents the distance between the zoom lens 102 before the power is turned on and the reset switch position 133.
[0111]
Therefore, in S913, the value of the counter Cz at this time is temporarily stored in the memory C0, and the counter Cz is a numerical value indicating the position of the reset switch measured or determined in advance (for example, in the optical design within the zoom lens movement range). The value obtained by converting the reset switch position measured from the determined origin into the number of stepping pulses of the motor 121) is substituted in S914. When the process of S914 is completed, the resetting of the zoom lens position detection counter Cz is completed.
[0112]
Next, in S915, the value of the memory C0 is subtracted from the value of the counter Cz newly determined in S914, and the result is substituted into the memory C0. In S915, the absolute position of the first zoom lens 102 is obtained with the position of the reset switch measured from a certain origin as a reference (from which the distance between the reset switch and the first zoom lens position is subtracted) and substituted into the memory C0. Therefore, if the zoom lens 102 is moved until the value of the counter Cz reaches the value of the memory C0, it can return to the position before the power is turned on.
[0113]
Note that when passing through S905 and S911, the value of C0 stored in S913 is a negative value. If this value is substituted in the equation of S915 as it is, the result becomes larger than the counter Cz in S914. This means that the lens position is on the tele side of the reset switch, so there is no problem.
[0114]
The first lens position is obtained as described above, and the process proceeds to S916. The process moves to S916, where it is determined whether the destination position memory C0 is equal to the zoom lens position counter Cz that has been reset. If true, the zoom lens position is already in the return destination position, and the process goes to S926. If false in step S916, it is determined in step S917 whether the return position C0 is greater than the current zoom position Cz. If it is larger, the return direction is assumed to be the tele direction, and the zoom lens is driven in the tele direction in S918, and the zoom position counter Cz is incremented.
[0115]
On the other hand, if it is determined to be false in S917, the return destination position is on the wide side of the current position of the zoom lens, and the process of S919 is performed at that time. Then, the zoom reset mode Mz is set to 3, and the process proceeds to S921 from the next time.
[0116]
In S921, it is determined whether or not the moving direction of the zoom lens 102 is the tele direction. If it is the tele direction, it is confirmed in S922 whether the return position C0 has been reached. If the arrival is confirmed, the process goes to S926, and if it has not reached yet, the lens is driven in the tele direction in S924.
[0117]
On the other hand, if it is determined in S921 that the zoom lens has moved in the wide direction, it is checked in S923 whether the zoom lens has reached the return destination position, and if it has reached, the process proceeds to S926 to set Mz = 4, and S927. Press to stop the zoom lens. If it has not been reached, the movement in the S925 wide direction is performed, and the process exits without updating the mode.
[0118]
In S922 and S923, the comparison between the zoom position counter Cz and the return destination position C0 also permits Cz to pass through the return destination position C0, but in practice the discrimination cycle is faster than the moving speed of the zoom lens. Therefore, the zoom is stopped when Cz = C0. When the zoom reset mode Mz becomes 4, all the zoom lens reset operations are completed, and when coming to S901 from the next time, the present process is exited as in S928 of Mz = 4.
[0119]
Further, the detailed description of the focus reset operation processing S805 in FIG. 15 is omitted, but the same processing can be performed by applying the processing shown in FIG. 16 to the focus lens 105 and the focus reset photosensor 136. The reset completion determination in S806 is performed by determining whether both the zoom and focus reset modes are 4.
[0120]
15 and 16 have been described as being performed in synchronization with the vertical synchronization signal, but the lens movement amount per vertical synchronization time V is determined by each of the processes S904, S905, S910, S911, S918, S919, and S919. , 924, and S925, one pulse. If the vertical synchronization period is 1/60 seconds, the moving speed of the lens is 60 pps. For example, when the stroke of the zoom lens is about 1200 pulses equivalent to 10 times and the reset reference position is provided at the center thereof, it takes a long time to complete the reset for 20 seconds at the longest.
[0121]
Therefore, in practice, the processing of FIG. 15 is not a processing routine synchronized with vertical synchronization, but is preferably an interrupt processing that interrupts at a cycle corresponding to the maximum speed of the step motor. For example, if the maximum speed of the stepping motor at which the lens does not step out is about 1200 pps, the processing in FIG. 15 is interrupted at 1/1200 seconds (in this case, the processing at 803 is an interrupt waiting time with a cycle of 1/1200 seconds). It becomes possible to complete the zoom stroke of 1200 pulses with a reset time of about 1 second.
[0122]
Further, the flange back information of DLTC initial communication in FIG. 14 has already been described as being corrected by offsetting to the focus absolute position that has been reset in S1321 in FIG. 14, but communication processing and lens reset processing are independently performed in parallel. Since the control can be performed, an offset amount may be added to the focus reset position value to be substituted into the focus lens position counter Cf in the focus processing corresponding to S914 in FIG.
[0123]
【The invention's effect】
As described above, according to the present invention, the initialization processing for initializing the position of the movable lens group included in the lens unit and the communication processing for communication between the lens and the camera body are independently performed in parallel. As a result, not only the lens system of the front lens type but also the lens system of the inner focus type can not only replace the lens but also shorten the time required for the lens position initialization operation. It becomes possible to shorten the time required for the subsequent image output.
[0124]
In particular, by providing a correction unit that corrects a movable lens position that is initialized based on correction information such as flange back deviation information obtained by the communication unit during or after completion of the initialization process, Even if there is a large error in the flange pack length of each camera unit, the lens position is corrected so as to eliminate the error, making it possible to realize an inner focus type interchangeable lens system that does not blur during zooming. Even if a lens unit of any lens type and a camera unit of any type are combined, it is possible to realize a zooming function without blurring.
[Brief description of the drawings]
FIG. 1 is a configuration diagram showing an embodiment of the present invention.
FIG. 2 is a block diagram illustrating a configuration of an AF processing unit.
FIG. 3 is a configuration diagram showing a frame generation operation;
FIG. 4 is a flowchart showing an automatic focus adjustment operation.
FIG. 5 is a configuration diagram of a reset switch.
FIG. 6 is a characteristic diagram for explaining a trajectory tracking method.
FIG. 7 is a characteristic diagram for explaining an interpolation method in the position direction of the variable magnification lens.
FIG. 8 is a configuration diagram showing communication lines between a main body microcomputer and a lens microcomputer.
FIG. 9 is a timing chart showing communication timing.
FIG. 10 is a configuration diagram showing communication contents.
FIG. 11 is a detailed configuration diagram of a header.
FIG. 12 is a timing chart for explaining communication handshaking.
FIG. 13 is a flowchart showing a communication operation of the main body microcomputer.
FIG. 14 is a flowchart showing a communication operation of the lens microcomputer.
FIG. 15 is a flowchart showing a lens reset operation.
16 is a flowchart showing in detail a part of the processing of FIG.
FIG. 17 is a configuration diagram showing a conventional interchangeable lens system.
FIG. 18 is a flowchart showing a communication operation of a conventional camera body.
FIG. 19 is a flowchart showing a communication operation of a conventional lens unit.
FIG. 20 is a configuration diagram of an inner focus type lens system.
FIG. 21 is a characteristic diagram showing the relationship between the focal length of the variable power lens and the position of the focus type lens for each subject distance.
[Explanation of symbols]
102 Zoom lens
105 Focus lens
106-108 Image sensor
112 Camera signal processor
113 AF signal processor
114 Microcomputer
115 communication line
116 Lens microcomputer
117 AF program
118 Monitor control unit
120 Lens cam data
121 Zoom motor
122 Motor driver
125 focus motor
126 Motor driver
127 Lens unit
128 Camera body
132 Reset control unit
134, 136 Photosensor

Claims (12)

In a lens apparatus having a lens system that is detachably connected to an imaging apparatus and includes a movable lens,
Initialization means for performing initialization processing of the position of the movable lens;
A lens apparatus comprising: a communication unit configured to perform communication processing with the imaging apparatus in parallel independently of the initialization processing. The correction means for correcting the position of the movable lens based on correction information obtained from the imaging device via the communication means during execution or termination of the initialization process is provided. Lens device. The initialization means is configured to send information indicating the end of the initialization process to the imaging device via the communication means, detect the position of the movable lens, and detect the detected position information as the communication means. And a control means for controlling the position of the movable lens based on control information obtained from the imaging apparatus via the communication means. The lens apparatus according to 1. A lens system having a movable lens;
An initialization means for performing an initialization process of the position of the movable lens and outputting information indicating the end of the process;
A lens unit having first communication means for performing communication of various types of information and performing the communication process in parallel independently of the initialization process;
Second communication means for performing communication processing with the first communication means;
Imaging means for imaging a subject image formed through the lens system and outputting an image signal;
Image processing means for processing the image signal;
A camera body having prohibiting means for prohibiting output of the image signal processed by the image processing means until information indicating completion of the initialization processing is obtained from the initialization means through the first and second communication means An imaging apparatus comprising: The camera body is provided with generating means for generating correction information, and the lens unit is obtained from the camera body via the first and second communication means during or when the initialization process is being executed. 5. The imaging apparatus according to claim 4, further comprising correction means for correcting the position of the movable lens based on correction information. A procedure for initializing the position of the movable lens in a lens device having a lens system that is detachably connected to the imaging device and includes a movable lens;
A computer-readable recording medium storing a program for executing a procedure for performing communication processing with the imaging apparatus in parallel with the initialization processing in parallel. 7. The computer according to claim 6, wherein a program for executing a procedure for correcting the position of the movable lens based on information obtained from the imaging device through the communication process when the initialization process is being executed or ended is recorded. A readable recording medium. It consists of an imaging device body and accessories such as a lens detachably connected to the imaging device body,
Initialization means for initializing the accessory;
An image pickup apparatus comprising: a communication unit configured to perform communication processing between the image pickup apparatus main body and the accessory in parallel independently of the initialization process. 9. A correction unit that corrects the position of the movable part of the accessory based on correction information obtained from the imaging device via the communication unit when the initialization process is being executed or ended. The imaging device described. The initialization unit is configured to send information indicating the end of the initialization process to the imaging apparatus via the communication unit, detect the position of the movable part, and detect the detected position information as the communication unit. And a control means for controlling the position of the movable part based on control information obtained from the imaging apparatus via the communication means. 8. The imaging device according to 8. A lens system having a movable lens;
Initialization means for performing initialization processing of the position of the movable lens;
A lens unit having first communication means for performing communication of various types of information and performing the communication process in parallel independently of the initialization process;
Second communication means for performing communication processing with the first communication means;
A camera body having control means for causing the second communication means to start communication with the first communication means in response to power-on, and to operate the initialization means independently and in parallel. Imaging device. The camera body is provided with generating means for generating correction information, and the lens unit is obtained from the camera body via the first and second communication means during or when the initialization process is being executed. 12. The imaging apparatus according to claim 11, further comprising correction means for correcting the position of the movable lens based on correction information.

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